ACAT1 deletion in murine macrophages associated with cytotoxicity and decreased expression of collagen type 3A1

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Rodriguez, Annabelle; Ashen, M. Dominique; Chen, Edward S.

2005-01-01

In contrast to some published studies of murine macrophages, we previously showed that ACAT inhibitors appeared to be anti-atherogenic in primary human macrophages in that they decreased foam cell formation without inducing cytotoxicity. Herein, we examined foam cell formation and cytotoxicity in murine ACAT1 knockout (KO) macrophages in an attempt to resolve the discrepancies. Elicited peritoneal macrophages from normal C57BL6 and ACAT1 KO mice were incubated with DMEM containing acetylated LDL (acLDL, 100 μg protein/ml) for 48 h. Cells became cholesterol enriched and there were no differences in the total cholesterol mass. Esterified cholesterol mass was lower in ACAT1 KO foam cells compared to normal macrophages (p 14 C]adenine from macrophages, was approximately 2-fold greater in ACAT1 KO macrophages as compared to normal macrophages (p < 0.0001), and this was independent of cholesterol enrichment. cDNA microarray analysis showed that ACAT1 KO macrophages expressed substantially less collagen type 3A1 (26-fold), which was confirmed by RT-PCR. Total collagen content was also significantly reduced (57%) in lung homogenates isolated from ACAT1 KO mice (p < 0.02). Thus, ACAT1 KO macrophages show biochemical changes consistent with increased cytotoxicity and also a novel association with decreased expression of collagen type 3A1

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

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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

An incomplete TCA cycle increases survival of Salmonella Typhimurium during infection of resting and activated murine macrophages.

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Bowden, Steven D; Ramachandran, Vinoy K; Knudsen, Gitte M; Hinton, Jay C D; Thompson, Arthur

2010-11-08

In comparison to the comprehensive analyses performed on virulence gene expression, regulation and action, the intracellular metabolism of Salmonella during infection is a relatively under-studied area. We investigated the role of the tricarboxylic acid (TCA) cycle in the intracellular replication of Salmonella Typhimurium in resting and activated macrophages, epithelial cells, and during infection of mice. We constructed deletion mutations of 5 TCA cycle genes in S. Typhimurium including gltA, mdh, sdhCDAB, sucAB, and sucCD. We found that the mutants exhibited increased net intracellular replication in resting and activated murine macrophages compared to the wild-type. In contrast, an epithelial cell infection model showed that the S. Typhimurium ΔsucCD and ΔgltA strains had reduced net intracellular replication compared to the wild-type. The glyoxylate shunt was not responsible for the net increased replication of the TCA cycle mutants within resting macrophages. We also confirmed that, in a murine infection model, the S. Typhimurium ΔsucAB and ΔsucCD strains are attenuated for virulence. Our results suggest that disruption of the TCA cycle increases the ability of S. Typhimurium to survive within resting and activated murine macrophages. In contrast, epithelial cells are non-phagocytic cells and unlike macrophages cannot mount an oxidative and nitrosative defence response against pathogens; our results show that in HeLa cells the S. Typhimurium TCA cycle mutant strains show reduced or no change in intracellular levels compared to the wild-type. The attenuation of the S. Typhimurium ΔsucAB and ΔsucCD mutants in mice, compared to their increased net intracellular replication in resting and activated macrophages suggest that Salmonella may encounter environments within the host where a complete TCA cycle is advantageous.

Fluid-Phase Pinocytosis of Native Low Density Lipoprotein Promotes Murine M-CSF Differentiated Macrophage Foam Cell Formation

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Xu, Qing; Bohnacker, Thomas; Wymann, Matthias P.; Kruth, Howard S.

2013-01-01

During atherosclerosis, low-density lipoprotein (LDL)-derived cholesterol accumulates in macrophages to form foam cells. Macrophage uptake of LDL promotes foam cell formation but the mechanism mediating this process is not clear. The present study investigates the mechanism of LDL uptake for macrophage colony-stimulating factor (M-CSF)-differentiated murine bone marrow-derived macrophages. LDL receptor-null (LDLR−/−) macrophages incubated with LDL showed non-saturable accumulation of cholesterol that did not down-regulate for the 24 h examined. Incubation of LDLR−/− macrophages with increasing concentrations of 125I-LDL showed non-saturable macrophage LDL uptake. A 20-fold excess of unlabeled LDL had no effect on 125I-LDL uptake by wild-type macrophages and genetic deletion of the macrophage scavenger receptors CD36 and SRA did not affect 125I-LDL uptake, showing that LDL uptake occurred by fluid-phase pinocytosis independently of receptors. Cholesterol accumulation was inhibited approximately 50% in wild-type and LDLR−/− mice treated with LY294002 or wortmannin, inhibitors of all classes of phosphoinositide 3-kinases (PI3K). Time-lapse, phase-contrast microscopy showed that macropinocytosis, an important fluid-phase uptake pathway in macrophages, was blocked almost completely by PI3K inhibition with wortmannin. Pharmacological inhibition of the class I PI3K isoforms alpha, beta, gamma or delta did not affect macrophage LDL-derived cholesterol accumulation or macropinocytosis. Furthermore, macrophages from mice expressing kinase-dead class I PI3K beta, gamma or delta isoforms showed no decrease in cholesterol accumulation or macropinocytosis when compared with wild-type macrophages. Thus, non-class I PI3K isoforms mediated macropinocytosis in these macrophages. Further characterization of the components necessary for LDL uptake, cholesterol accumulation, and macropinocytosis identified dynamin, microtubules, actin, and vacuolar type H(+)-ATPase as

Assessment of Antibody-based Drugs Effects on Murine Bone Marrow and Peritoneal Macrophage Activation.

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Kozicky, Lisa; Sly, Laura M

2017-12-26

Macrophages are phagocytic innate immune cells, which initiate immune responses to pathogens and contribute to healing and tissue restitution. Macrophages are equally important in turning off inflammatory responses. We have shown that macrophages stimulated with intravenous immunoglobulin (IVIg) can produce high amounts of the anti-inflammatory cytokine, interleukin 10 (IL-10), and low levels of pro-inflammatory cytokines in response to bacterial lipopolysaccharides (LPS). IVIg is a polyvalent antibody, primarily immunoglobulin Gs (IgGs), pooled from the plasma of more than 1,000 blood donors. It is used to supplement antibodies in patients with immune deficiencies or to suppress immune responses in patients with autoimmune or inflammatory conditions. Infliximab, a therapeutic anti-tumor necrosis factor alpha (TNFα) antibody, has also been shown to activate macrophages to produce IL-10 in response to inflammatory stimuli. IVIg and other antibody-based biologics can be tested to determine their effects on macrophage activation. This paper describes methods for derivation, stimulation, and assessment of murine bone marrow macrophages activated by antibodies in vitro and murine peritoneal macrophages activated with antibodies in vivo. Finally, we demonstrate the use of western blotting to determine the contribution of specific cell signaling pathways to anti-inflammatory macrophage activity. These protocols can be used with genetically modified mice, to determine the effect of a specific protein(s) on anti-inflammatory macrophage activation. These techniques can also be used to assess whether specific biologics may act by changing macrophages to an IL-10-producing anti-inflammatory activation state that reduces inflammatory responses in vivo. This can provide information on the role of macrophage activation in the efficacy of biologics during disease models in mice, and provide insight into a potential new mechanism of action in people. Conversely, this may caution

Crotoxin stimulates an M1 activation profile in murine macrophages during Leishmania amazonensis infection.

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Farias, L H S; Rodrigues, A P D; Coêlho, E C; Santos, M F; Sampaio, S C; Silva, E O

2017-09-01

American tegumentary leishmaniasis is caused by different species of Leishmania. This protozoan employs several mechanisms to subvert the microbicidal activity of macrophages and, given the limited efficacy of current therapies, the development of alternative treatments is essential. Animal venoms are known to exhibit a variety of pharmacological activities, including antiparasitic effects. Crotoxin (CTX) is the main component of Crotalus durissus terrificus venom, and it has several biological effects. Nevertheless, there is no report of CTX activity during macrophage - Leishmania interactions. Thus, the main objective of this study was to evaluate whether CTX has a role in macrophage M1 polarization during Leishmania infection murine macrophages, Leishmania amazonensis promastigotes and L. amazonensis-infected macrophages were challenged with CTX. MTT [3-(4,5dimethylthiazol-2-yl)-2,5-diphenyl tetrasodium bromide] toxicity assays were performed on murine macrophages, and no damage was observed in these cells. Promastigotes, however, were affected by treatment with CTX (IC50 = 22·86 µg mL-1) as were intracellular amastigotes. Macrophages treated with CTX also demonstrated increased reactive oxygen species production. After they were infected with Leishmania, macrophages exhibited an increase in nitric oxide production that converged into an M1 activation profile, as suggested by their elevated production of the cytokines interleukin-6 and tumour necrosis factor-α and changes in their morphology. CTX was able to reverse the L. amazonensis-mediated inhibition of macrophage immune responses and is capable of polarizing macrophages to the M1 profile, which is associated with a better prognosis for cutaneous leishmaniasis treatment.

Induced-Pluripotent-Stem-Cell-Derived Primitive Macrophages Provide a Platform for Modeling Tissue-Resident Macrophage Differentiation and Function.

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Takata, Kazuyuki; Kozaki, Tatsuya; Lee, Christopher Zhe Wei; Thion, Morgane Sonia; Otsuka, Masayuki; Lim, Shawn; Utami, Kagistia Hana; Fidan, Kerem; Park, Dong Shin; Malleret, Benoit; Chakarov, Svetoslav; See, Peter; Low, Donovan; Low, Gillian; Garcia-Miralles, Marta; Zeng, Ruizhu; Zhang, Jinqiu; Goh, Chi Ching; Gul, Ahmet; Hubert, Sandra; Lee, Bernett; Chen, Jinmiao; Low, Ivy; Shadan, Nurhidaya Binte; Lum, Josephine; Wei, Tay Seok; Mok, Esther; Kawanishi, Shohei; Kitamura, Yoshihisa; Larbi, Anis; Poidinger, Michael; Renia, Laurent; Ng, Lai Guan; Wolf, Yochai; Jung, Steffen; Önder, Tamer; Newell, Evan; Huber, Tara; Ashihara, Eishi; Garel, Sonia; Pouladi, Mahmoud A; Ginhoux, Florent

2017-07-18

Tissue macrophages arise during embryogenesis from yolk-sac (YS) progenitors that give rise to primitive YS macrophages. Until recently, it has been impossible to isolate or derive sufficient numbers of YS-derived macrophages for further study, but data now suggest that induced pluripotent stem cells (iPSCs) can be driven to undergo a process reminiscent of YS-hematopoiesis in vitro. We asked whether iPSC-derived primitive macrophages (iMacs) can terminally differentiate into specialized macrophages with the help of growth factors and organ-specific cues. Co-culturing human or murine iMacs with iPSC-derived neurons promoted differentiation into microglia-like cells in vitro. Furthermore, murine iMacs differentiated in vivo into microglia after injection into the brain and into functional alveolar macrophages after engraftment in the lung. Finally, iPSCs from a patient with familial Mediterranean fever differentiated into iMacs with pro-inflammatory characteristics, mimicking the disease phenotype. Altogether, iMacs constitute a source of tissue-resident macrophage precursors that can be used for biological, pathophysiological, and therapeutic studies. Copyright © 2017 Elsevier Inc. All rights reserved.

The influence of macrophage growth factors on Theiler's Murine Encephalomyelitis Virus (TMEV) infection and activation of macrophages.

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Schneider, Karin M; Watson, Neva B; Minchenberg, Scott B; Massa, Paul T

2018-02-01

Macrophages are common targets for infection and innate immune activation by many pathogenic viruses including the neurotropic Theiler's Murine Encephalomyelitis Virus (TMEV). As both infection and innate activation of macrophages are key determinants of viral pathogenesis especially in the central nervous system (CNS), an analysis of macrophage growth factors on these events was performed. C3H mouse bone-marrow cells were differentiated in culture using either recombinant macrophage colony stimulating factor (M-CSF) or granulocyte-macrophage colony-stimulating factor (GM-CSF), inoculated with TMEV (BeAn) and analyzed at various times thereafter. Cytokine RNA and protein analysis, virus titers, and flow cytometry were performed to characterize virological parameters under these culture conditions. GM-CSF-differentiated macrophages showed higher levels of TMEV viral RNA and proinflammatory molecules compared to infected M-CSF-differentiated cells. Thus, GM-CSF increases both TMEV infection and TMEV-induced activation of macrophages compared to that seen with M-CSF. Moreover, while infectious viral particles decreased from a peak at 12h to undetectable levels at 48h post infection, TMEV viral RNA remained higher in GM-CSF- compared to M-CSF-differentiated macrophages in concert with increased proinflammatory gene expression. Analysis of a possible basis for these differences determined that glycolytic rates contributed to heightened virus replication and proinflammatory cytokine secretion in GM-CSF compared to M-CSF-differentiated macrophages. In conclusion, we provide evidence implicating a role for GM-CSF in promoting virus replication and proinflammatory cytokine expression in macrophages, indicating that GM-CSF may be a key factor for TMEV infection and the induction of chronic TMEV-induced immunopathogenesis in the CNS. Copyright © 2017 Elsevier Ltd. All rights reserved.

Dextran sulfate sodium upregulates MAPK signaling for the uptake and subsequent intracellular survival of Brucella abortus in murine macrophages.

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Reyes, Alisha Wehdnesday Bernardo; Arayan, Lauren Togonon; Simborio, Hannah Leah Tadeja; Hop, Huynh Tan; Min, WonGi; Lee, Hu Jang; Kim, Dong Hee; Chang, Hong Hee; Kim, Suk

2016-02-01

Brucellosis is one of the major zoonoses worldwide that inflicts important health problems in animal and human. Here, we demonstrated that dextran sulfate sodium (DSS) significantly increased adhesion of Brucella (B.) abortus in murine macrophages compared to untreated cells. Even without infection, Brucella uptake into macrophages increased and F-actin reorganization was induced compared with untreated cells. Furthermore, DSS increased the phosphorylation of MAPKs (ERK1/2 and p38α) in Brucella-infected, DSS-treated cells compared with the control cells. Lastly, DSS markedly increased the intracellular survival of Brucella abortus in macrophages by up to 48 h. These results suggest that DSS enhanced the adhesion and phagocytosis of B. abortus into murine macrophages by stimulating the MAPK signaling proteins phospho-ERK1/2 and p38α and that DSS increased the intracellular survival of B. abortus by inhibiting colocalization of Brucella-containing vacuoles (BCVs) with the late endosome marker LAMP-1. This study emphasizes the enhancement of the phagocytic and intracellular modulatory effects of DSS, which may suppress the innate immune system and contribute to prolonged Brucella survival and chronic infection. Copyright © 2015 Elsevier Ltd. All rights reserved.

Reliable and inexpensive expression of large, tagged, exogenous proteins in murine bone marrow-derived macrophages using a second generation lentiviral system

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Matthew R. Miller

2015-08-01

Full Text Available Over the past two decades, researchers have struggled to efficiently express foreign DNA in primary macrophages, impeding research progress. The applications of lipofection, electroporation, microinjection, and viral-mediated transfer typically result in disruptions in macrophage differentiation and function, low expression levels of exogenous proteins, limited efficiency and high cell mortality. In this report, after extensive optimization, we present a method of expressing large tagged proteins at high efficiency, consistency, and low cost using lentiviral infection. This method utilizes laboratory-propagated second generation plasmids to produce efficient virus that can be stored for later use. The expression of proteins up to 150 kDa in size is achieved in 30–70% of cells while maintaining normal macrophage differentiation and morphology as determined by fluorescence microscopy and Western blot analysis. This manuscript delineates the reagents and methods used to produce lentivirus to express exogenous DNA in murine bone marrow-derived macrophages sufficient for single cell microscopy as well as functional assays requiring large numbers of murine bone marrow-derived macrophages.

Lactobacillus delbrueckii subsp. lactis (strain CIDCA 133) stimulates murine macrophages infected with Citrobacter rodentium.

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Hugo, Ayelén A; Rolny, Ivanna S; Romanin, David; Pérez, Pablo F

2017-03-01

Citrobacter rodentium is a specific murine enteropathogen which causes diarrheal disease characterized by colonic hyperplasia and intestinal inflammation. Recruitment of neutrophils and macrophages constitute a key step to control the infection. Since modulation of the activity of professional phagocytic cells could contribute to improve host´s defences against C. rodentium, we investigated the effect of Lactobacillus delbrueckii subsp. lactis (strain CIDCA 133) on the interaction between murine macrophages (RAW 264.7) and C. rodentium. Phagocytosis, surface molecules and inducible nitric oxide synthase (iNOs) expression were determined by flow cytometry. Reactive oxygen species (ROS) were assessed by fluorescence microscopy. The presence of lactobacilli increased phagocytosis of C. rodentium whereas C. rodentium had no effect on lactobacilli internalization. Survival of internalized C. rodentium diminished when strain CIDCA 133 was present. CD-86, MHCII, iNOs expression and nitrite production were increased when C. rodentium and lactobacilli were present even though strain CIDCA 133 alone had no effect. Strain CIDCA 133 led to a strong induction of ROS activity which was not modified by C. rodentium. Lactobacillus delbrueckii subsp. lactis (strain CIDCA 133) is able to increase the activation of murine macrophages infected with C. rodentium. The sole presence of lactobacilli is enough to modify some stimulation markers (e.g. ROS induction) whereas other markers require the presence of both bacteria; thus, indicating a synergistic effect.

Homocysteine elicits an M1 phenotype in murine macrophages through an EMMPRIN-mediated pathway.

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Winchester, Lee J; Veeranki, Sudhakar; Givvimani, Srikanth; Tyagi, Suresh C

2015-07-01

Hyperhomocysteinemia (HHcy) is associated with inflammatory diseases and is known to increase the production of reactive oxygen species (ROS), matrix metalloproteinase (MMP)-9, and inducible nitric oxide synthase, and to decrease endothelial nitric oxide production. However, the impact of HHcy on macrophage phenotype differentiation is not well-established. It has been documented that macrophages have 2 distinct phenotypes: the "classically activated/destructive" (M1), and the "alternatively activated/constructive" (M2) subtypes. We hypothesize that HHcy increases M1 macrophage differentiation through extracellular matrix metalloproteinase inducer (EMMPRIN), a known inducer of matrix metalloproteinases. murine J774A.1 and Raw 264.7 macrophages were treated with 100 and 500 μmol/L Hcy, respectively, for 24 h. Samples were analyzed using Western blotting and immunocytochemistry. Homocysteine treatment increased cluster of differentiation 40 (CD40; M1 marker) in J774A.1 and Raw 264.7 macrophages. MMP-9 was induced in both cell lines. EMMPRIN protein expression was also increased in both cell lines. Blocking EMMPRIN function by pre-treating cells with anti-EMMPRIN antibody, with or without Hcy, resulted in significantly lower expression of CD40 in both cell lines by comparison with the controls. A DCFDA assay demonstrated increased ROS production in both cell lines with Hcy treatment when compared with the controls. Our results suggest that HHcy results in an increase of the M1 macrophage phenotype. This effect seems to be at least partially mediated by EMMPRIN induction.

Alternate radiolabeled markers for detecting metabolic activity of Mycobacterium leprae residing in murine macrophages

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Prasad, H.K.; Hastings, R.C.

1985-01-01

This study demonstrated the utility of using 4% NaOH as a murine macrophage cell-solubilizing agent to discriminate between host macrophage metabolism and that of intracellular Mycobacterium leprae. A 4% concentration of NaOH had no deleterious effect on labeled mycobacteria. Thereby, alternate radiolabeled indicators of the metabolic activity of intracellular M. leprae could be experimented with. Significant incorporation of 14 C-amino acid mixture, [ 14 C]leucine, [ 14 C]uridine, and carrier-free 32 P was observed in cultures containing freshly extracted (''live'') strains of M. leprae as compared with control cultures containing autoclaved bacilli

Shigella mediated depletion of macrophages in a murine breast cancer model is associated with tumor regression.

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Katharina Galmbacher

Full Text Available A tumor promoting role of macrophages has been described for a transgenic murine breast cancer model. In this model tumor-associated macrophages (TAMs represent a major component of the leukocytic infiltrate and are associated with tumor progression. Shigella flexneri is a bacterial pathogen known to specificly induce apotosis in macrophages. To evaluate whether Shigella-induced removal of macrophages may be sufficient for achieving tumor regression we have developed an attenuated strain of S. flexneri (M90TDeltaaroA and infected tumor bearing mice. Two mouse models were employed, xenotransplantation of a murine breast cancer cell line and spontanous breast cancer development in MMTV-HER2 transgenic mice. Quantitative analysis of bacterial tumor targeting demonstrated that attenuated, invasive Shigella flexneri primarily infected TAMs after systemic administration. A single i.v. injection of invasive M90TDeltaaroA resulted in caspase-1 dependent apoptosis of TAMs followed by a 74% reduction in tumors of transgenic MMTV-HER-2 mice 7 days post infection. TAM depletion was sustained and associated with complete tumor regression.These data support TAMs as useful targets for antitumor therapy and highlight attenuated bacterial pathogens as potential tools.

Corn silk induced cyclooxygenase-2 in murine macrophages.

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Kim, Kyung A; Shin, Hyun-Hee; Choi, Sang Kyu; Choi, Hye-Seon

2005-10-01

Stimulation of murine macrophages with corn silk induced cyclooxygenase (COX)-2 with secretion of PGE2. Expression of COX-2 was inhibited by pyrolidine dithiocarbamate (PDTC), and increased DNA binding by nuclear factor kappa B (NF-kappaB), indicating that COX-2 induction proceeds also via the NF-kappaB signaling pathway. A specific inhibitor of COX-2 decreased the expression level of inducible nitric oxide synthase (iNOS) stimulated by corn silk. PGE2 elevated the expression level of iNOS, probably via EP2 and EP4 receptors on the surface of the macrophages.

Inhibition of inducible Nitric Oxide Synthase by a mustard gas analog in murine macrophages

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Smith Milton

2006-11-01

Full Text Available Abstract Background 2-Chloroethyl ethyl sulphide (CEES is a sulphur vesicating agent and an analogue of the chemical warfare agent 2,2'-dichlorodiethyl sulphide, or sulphur mustard gas (HD. Both CEES and HD are alkylating agents that influence cellular thiols and are highly toxic. In a previous publication, we reported that lipopolysaccharide (LPS enhances the cytotoxicity of CEES in murine RAW264.7 macrophages. In the present investigation, we studied the influence of CEES on nitric oxide (NO production in LPS stimulated RAW264.7 cells since NO signalling affects inflammation, cell death, and wound healing. Murine macrophages stimulated with LPS produce NO almost exclusively via inducible nitric oxide synthase (iNOS activity. We suggest that the influence of CEES or HD on the cellular production of NO could play an important role in the pathophysiological responses of tissues to these toxicants. In particular, it is known that macrophage generated NO synthesised by iNOS plays a critical role in wound healing. Results We initially confirmed that in LPS stimulated RAW264.7 macrophages NO is exclusively generated by the iNOS form of nitric oxide synthase. CEES treatment inhibited the synthesis of NO (after 24 hours in viable LPS-stimulated RAW264.7 macrophages as measured by either nitrite secretion into the culture medium or the intracellular conversion of 4,5-diaminofluorescein diacetate (DAF-2DA or dichlorofluorescin diacetate (DCFH-DA. Western blots showed that CEES transiently decreased the expression of iNOS protein; however, treatment of active iNOS with CEES in vitro did not inhibit its enzymatic activity Conclusion CEES inhibits NO production in LPS stimulated macrophages by decreasing iNOS protein expression. Decreased iNOS expression is likely the result of CEES induced alteration in the nuclear factor kappa B (NF-κB signalling pathway. Since NO can act as an antioxidant, the CEES induced down-regulation of iNOS in LPS

Alternate radiolabeled markers for detecting metabolic activity of Mycobacterium leprae residing in murine macrophages

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Prasad, H.K.; Hastings, R.C.

1985-05-01

This study demonstrated the utility of using 4% NaOH as a murine macrophage cell-solubilizing agent to discriminate between host macrophage metabolism and that of intracellular Mycobacterium leprae. A 4% concentration of NaOH had no deleterious effect on labeled mycobacteria. Thereby, alternate radiolabeled indicators of the metabolic activity of intracellular M. leprae could be experimented with. Significant incorporation of /sup 14/C-amino acid mixture, (/sup 14/C)leucine, (/sup 14/C)uridine, and carrier-free /sup 32/P was observed in cultures containing freshly extracted (''live'') strains of M. leprae as compared with control cultures containing autoclaved bacilli.

Cyclooxygenase-2 inhibition blocks M2 macrophage differentiation and suppresses metastasis in murine breast cancer model.

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Yi-Rang Na

Full Text Available Tumor cells are often associated with abundant macrophages that resemble the alternatively activated M2 subset. Tumor-associated macrophages (TAMs inhibit anti-tumor immune responses and promote metastasis. Cyclooxygenase-2 (COX-2 inhibition is known to prevent breast cancer metastasis. This study hypothesized that COX-2 inhibition affects TAM characteristics potentially relevant to tumor cell metastasis. We found that the specific COX-2 inhibitor, etodolac, inhibited human M2 macrophage differentiation, as determined by decreased CD14 and CD163 expressions and increased TNFα production. Several key metastasis-related mediators, such as vascular endothelial growth factor-A, vascular endothelial growth factor-C, and matrix metalloproteinase-9, were inhibited in the presence of etodolac as compared to untreated M2 macrophages. Murine bone marrow derived M2 macrophages also showed enhanced surface MHCII IA/IE and CD80, CD86 expressions together with enhanced TNFα expressions with etodolac treatment during differentiation. Using a BALB/c breast cancer model, we found that etodolac significantly reduced lung metastasis, possibly due to macrophages expressing increased IA/IE and TNFα, but decreased M2 macrophage-related genes expressions (Ym1, TGFβ. In conclusion, COX-2 inhibition caused loss of the M2 macrophage characteristics of TAMs and may assist prevention of breast cancer metastasis.

Macrophage content of murine tumors: Associations with TD50 and tumor radiocurability

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Wike, J.; Hunter, N.; Volpe, J.; Milas, L.

1987-01-01

The experiments were designed to investigate whether the tumor-associated macrophage (TAM) content of murine solid tumors correlates with tumor response to ionizing radiation and with the clonogenic ability of tumor cells to establish s.c. tumors. Of 13 tumors studied, 6 were sarcomas and 7 were carcinomas; all tumors were of spontaneous origin in C/sub 3/Hf/Kam mice, with the exception of one sarcoma that was induced by 3-methylcholanthrene. Tumors were growing in the hind thighs of syngeneic mice, and their TAM content was determined when they were 8 mm in diameter. Their macrophage content varied greatly, ranging from 9 to 83%. Radiocurability of 8 mm tumors, determined by TCD50, ranged from 42 Gy (fibrosarcoma FSA) to > 80 Gy (hepatocarcinoma HCA-I). There was an obvious trend toward positive correlation (r = 0.43) between TAM content and reduced local tumor radiocurability. However, there was a significant negative correlation between TAM content and TD50 values, implying that cells from tumors with higher macrophage content were more clonogenic. TAM from the NFSA sarcoma, a tumor with a low TD50 value and poorly responsive to radiation, stimulated the in vitro growth of NFSA tumor cells. These observations suggest that high TAM content could be conducive to tumor cell proliferation and could be a factor in poor tumor radioresponse

Effect of bleaching agent extracts on murine macrophages.

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Fernandes, Aletéia M M; Vilela, Polyana G F; Valera, Marcia C; Bolay, Carola; Hiller, Karl Anton; Schweikl, Helmut; Schmalz, Gottfried

2018-05-01

The aim of this study was to evaluate the cytotoxicity and the influence of bleaching agents on immunologically cell surface antigens of murine macrophages in vitro. RAW 264.7 cells were exposed to bleaching gel extracts (40% hydrogen peroxide or 20% carbamide peroxide) and different H 2 O 2 concentrations after 1 and 24-h exposure periods and 1-h exposure and 23-h recovery. Tests were performed with and without N-acetyl cysteine (NAC) and buthionine sulfoximine (BSO). Cell viability was determined by MTT assay. The expression of surface markers CD14, CD40, and CD54 with and without LPS stimulation was detected by flow cytometry, while the production of TNF-α was measured by ELISA. Statistical analysis was performed using the Mann-Whitney U test (α = 0.05). Extracts of bleaching agents were cytotoxic for cells after a 1-h exposure; cells could not recover after 24 h. This effect can be mitigated by the antioxidant NAC and increased by BSO, an inhibitor of glutathione (GSH) synthesis. LPS stimulated expression of all surface markers and TNF-α production. Exposure to bleaching agent extracts and H 2 O 2 leads to a reduction of TNF-α, CD14, and CD40 expression, while the expression of CD54 was upregulated at non-cytotoxic concentrations. Whereas NAC reduced this effect, it was increased in the presence of BSO. Extracts of bleaching agents were irreversibly cytotoxic to macrophages after a 1-h exposure. Only the expression of CD54 was upregulated. The reactions are mediated by the non-enzymatic antioxidant GSH. The addition of an antioxidant can downregulate unfavorable effects of dental bleaching.

Phenolic and flavonoid compounds in aqueous extracts of thunbergia laurifolia leaves and their effect on the toxicity of the carbamate insecticide methomyl to murine macrophage cells

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Marasri Junsi

2017-07-01

Full Text Available Background: Thunbergia laurifolia is a Thai herb and has been used in Thai folklore medicine for centuries. Generally, Thais consume T. laurifolia as a herbal tea because of its beneficial properties as an antidote for chemical toxins, drug-, arsenic-, strychnine-, alcohol- and food-poisoning. However, its effectively against some insecticide compounds, e.g. methomyl, has not yet been determined. Objective: To examine the protective effect of aqueous extract from leaves of T. laurifolia on methomyl (MT poisoning of murine macrophage cells (anti-MT effect and to identify phenolic and flavonoid compounds in the extract. Methods: T. laurifolia was extracted with water and stored in freeze-dried form. The extract was investigated for its antioxidant activity and some phenolic and flavonoid compounds were identified using liquid chromatography–mass spectrometry (LC-MS. To study anti-MT effects in RAW264.7 murine macrophage cells, these were treated with leaf extract either before (pre-treatment, concomitantly (combined or after (post-treatment exposure to MT and cell viability determined in an MTT test (3-(4,5-dimethylthiazol-2-yl-2,5-diphenyltetrazolium bromide. Results: The extract exhibited strong antioxidant properties based on total extractable phenolic content (TPC, total extractable flavonoid content (TFC, 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid (ABTS radical scavenging, 2,2-diphenyl-1-picrylhydrazyl (DPPH radical scavenging and Ferric ion reducing antioxidant power (FRAP activity. The LC-MS analyses of phenolic compounds indicated the presence of caffeic acid, rosmarinic acid, catechin, rutin, isoquercetin, quercetin and apigenin as bioactive compounds. Viability of RAW 264.7 murine macrophage cells treated with MT was increased significantly by post-treatment with leaf extract but not by combined or pre-treatments. Conclusion: The aqueous extract of T. laurifolia leaves contained abundant antioxidant activity. Flavonoids

Entrance and Survival of Brucella pinnipedialis Hooded Seal Strain in Human Macrophages and Epithelial Cells

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Briquemont, Benjamin; Sørensen, Karen K.; Godfroid, Jacques

2013-01-01

Marine mammal Brucella spp. have been isolated from pinnipeds (B. pinnipedialis) and cetaceans (B. ceti) from around the world. Although the zoonotic potential of marine mammal brucellae is largely unknown, reports of human disease exist. There are few studies of the mechanisms of bacterial intracellular invasion and multiplication involving the marine mammal Brucella spp. We examined the infective capacity of two genetically different B. pinnipedialis strains (reference strain; NTCT 12890 and a hooded seal isolate; B17) by measuring the ability of the bacteria to enter and replicate in cultured phagocytes and epithelial cells. Human macrophage-like cells (THP-1), two murine macrophage cell lines (RAW264.7 and J774A.1), and a human malignant epithelial cell line (HeLa S3) were challenged with bacteria in a gentamicin protection assay. Our results show that B. pinnipedialis is internalized, but is then gradually eliminated during the next 72 – 96 hours. Confocal microscopy revealed that intracellular B. pinnipedialis hooded seal strain colocalized with lysosomal compartments at 1.5 and 24 hours after infection. Intracellular presence of B. pinnipedialis hooded seal strain was verified by transmission electron microscopy. By using a cholesterol-scavenging lipid inhibitor, entrance of B. pinnipedialis hooded seal strain in human macrophages was significantly reduced by 65.8 % (± 17.3), suggesting involvement of lipid-rafts in intracellular entry. Murine macrophages invaded by B. pinnipedialis do not release nitric oxide (NO) and intracellular bacterial presence does not induce cell death. In summary, B. pinnipedialis hooded seal strain can enter human and murine macrophages, as well as human epithelial cells. Intracellular entry of B. pinnipedialis hooded seal strain involves, but seems not to be limited to, lipid-rafts in human macrophages. Brucella pinnipedialis does not multiply or survive for prolonged periods intracellulary. PMID:24376851

Leucine supplementation attenuates macrophage foam-cell formation: Studies in humans, mice, and cultured macrophages.

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Grajeda-Iglesias, Claudia; Rom, Oren; Hamoud, Shadi; Volkova, Nina; Hayek, Tony; Abu-Saleh, Niroz; Aviram, Michael

2018-02-05

Whereas atherogenicity of dietary lipids has been largely studied, relatively little is known about the possible contribution of dietary amino acids to macrophage foam-cell formation, a hallmark of early atherogenesis. Recently, we showed that leucine has antiatherogenic properties in the macrophage model system. In this study, an in-depth investigation of the role of leucine in macrophage lipid metabolism was conducted by supplementing humans, mice, or cultured macrophages with leucine. Macrophage incubation with serum obtained from healthy adults supplemented with leucine (5 g/d, 3 weeks) significantly decreased cellular cholesterol mass by inhibiting the rate of cholesterol biosynthesis and increasing cholesterol efflux from macrophages. Similarly, leucine supplementation to C57BL/6 mice (8 weeks) resulted in decreased cholesterol content in their harvested peritoneal macrophages (MPM) in relation with reduced cholesterol biosynthesis rate. Studies in J774A.1 murine macrophages revealed that leucine dose-dependently decreased cellular cholesterol and triglyceride mass. Macrophages treated with leucine (0.2 mM) showed attenuated uptake of very low-density lipoproteins and triglyceride biosynthesis rate, with a concurrent down-regulation of diacylglycerol acyltransferase-1, a key enzyme catalyzing triglyceride biosynthesis in macrophages. Similar effects were observed when macrophages were treated with α-ketoisocaproate, a key leucine metabolite. Finally, both in vivo and in vitro leucine supplementation significantly improved macrophage mitochondrial respiration and ATP production. The above studies, conducted in human, mice, and cultured macrophages, highlight a protective role for leucine attenuating macrophage foam-cell formation by mechanisms related to the metabolism of cholesterol, triglycerides, and energy production. © 2018 BioFactors, 2018. © 2018 International Union of Biochemistry and Molecular Biology.

Effect of Tityus serrulatus venom on cytokine production and the activity of murine macrophages

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Vera L. Petricevich

2002-01-01

Full Text Available The purpose of this study was to investigate the effects of Tityus serrulatus venom (TSV on murine peritoneal macrophages evaluated in terms of activation. The effects of crude TSV were analysed by detection of cytokines, oxygen intermediate metabolites (H2O2 and nitric oxide (NO in supernatants of peritoneal macrophages. Several functional bioassays were employed including an in vitro model for envenomating: cytotoxicity of TSV was assessed using the lyses percentage. Tumor necrosis factor (TNF activity was assayed by measuring its cytotoxic activity on L-929 cells, and interleukin-6 (IL-6 and interferon-γ (IFN-γ were assayed by enzyme-linked immunosorbent assay, whereas NO levels were detected by Griess colorimetric reactions in culture supernatant of macrophages incubated with TSV and subsequently exposed to either lipopolysaccharide or IFN-γ. Incubation of macrophages with TSV increased production of IL-6 and IFN-γ in a dose-dependent manner. TNF production was not detected in supernatants treated with TSV at any concentration. The increase in IL-6 secretion was not associated with concentration-dependent cytoxicity of TSV on these cells. These data suggest that the cytotoxicity does not appear to be the main cause of an increased cytokine production by these cells. Although NO is an important effector molecule in macrophage microbicidal activity, the inducing potential of the test compounds for its release was found to be very moderate, ranging from 125 to 800 mM. Interestingly, NO levels of peritoneal macrophages were increased after IFN-γ. Moreover, NO production had an apparent effect on macrophage activity. The results obtained here also shown that the TSV induces an important elevation in H2O2 release. These results combined with NO production suggest that TSV possesses significant immunomodulatory activities capable of stimulating immune functions in vitro.

Bone marrow stromal elements in murine leukemia; Decreased CSF-producing fibroblasts and normal IL-1 expression by macrophages

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Ben-Ishay, Z [Laboratory of Experimental Hematology, Department of Anatomy and Embryology, Hebrew University-Hadassah Medical School (Israel); Barak, V [Laboratory of Immunology, Department of Oncology, Hadassah University Hospital (Israel); Shoshan, S [Faculty of Dental Medicine, Connective Tissue Research Laboratory, Hebrew University, Jerusalem (Israel); Prindull, G [Department of Pediatrics, University of Gottingen, Gottingen (Germany, F.R.)

1990-01-01

A study of bone marrow stromal elements in murine acute myeloid leukemia (AML) was carried out. Our previous studies had indicated marrow stromal deficiency in murine AML. In the current investigation, separate stromal cells were cultured and the results obtained have shown that, while marrow stromal macrophages are normal in leukemia and express adequate amounts of IL-1, the fibroblasts are markedly reduced. However, if sufficient fibroblasts are pooled in vitro, they produce adequate amounts of CSF. Test of TNF{alpha} in leukemic cells CM, as possible cause of marrow stromal inhibition in leukemia, had not disclosed this cytokine. Further, it was observed that total body lethal irradiation of leukemic mice aggravates the stromal deficiency, confirming results of our previous investigations. It is concluded that bone marrow stromal deficiency in murine AML is due to decreased fibroblasts and, implicity, reduced CSF production. (author).

Immunostimulating activity of maysin isolated from corn silk in murine RAW 264.7 macrophages.

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Lee, Jisun; Kim, Sun-Lim; Lee, Seul; Chung, Mi Ja; Park, Yong Il

2014-07-01

Corn silk (CS) has long been consumed as a traditional herb in Korea. Maysin is a major flavonoid of CS. The effects of maysin on macrophage activation were evaluated, using the murine macrophage RAW 264.7 cells. Maysin was isolated from CS by methanol extraction, and preparative C18 reverse phase column chromatography. Maysin was nontoxic up to 100 μg/ml, and dose-dependently increased TNF-α secretion and iNOS production by 11.2- and 4.2-fold, respectively, compared to untreated control. The activation and subsequent nuclear translocation of NF-κB was substantially enhanced upon treatment with maysin (1-100 μg/ml). Maysin also stimulated the phosphorylation of Akt and MAPKs (ERK, JNK). These results indicated that maysin activates macrophages to secrete TNF-α and induce iNOS expression, via the activation of the Akt, NF-κB and MAPKs signaling pathways. These results suggest for the first time that maysin can be a new immunomodulator, enhancing the early innate immunity.

Single-Cell RNA-Seq Reveals the Transcriptional Landscape and Heterogeneity of Aortic Macrophages in Murine Atherosclerosis.

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Cochain, Clément; Vafadarnejad, Ehsan; Arampatzi, Panagiota; Jaroslav, Pelisek; Winkels, Holger; Ley, Klaus; Wolf, Dennis; Saliba, Antoine-Emmanuel; Zernecke, Alma

2018-03-15

Rationale: It is assumed that atherosclerotic arteries contain several macrophage subsets endowed with specific functions. The precise identity of these subsets is poorly characterized as they ha ve been defined by the expression of a restricted number of markers. Objective: We have applied single-cell RNA-seq as an unbiased profiling strategy to interrogate and classify aortic macrophage heterogeneity at the single-cell level in atherosclerosis. Methods and Results: We performed single-cell RNA sequencing of total aortic CD45 + cells extracted from the non-diseased (chow fed) and atherosclerotic (11 weeks of high fat diet) aorta of Ldlr -/- mice. Unsupervised clustering singled out 13 distinct aortic cell clusters. Among the myeloid cell populations, Resident-like macrophages with a gene expression profile similar to aortic resident macrophages were found in healthy and diseased aortae, whereas monocytes, monocyte-derived dendritic cells (MoDC), and two populations of macrophages were almost exclusively detectable in atherosclerotic aortae, comprising Inflammatory macrophages showing enrichment in I l1b , and previously undescribed TREM2 hi macrophages. Differential gene expression and gene ontology enrichment analyses revealed specific gene expression patterns distinguishing these three macrophage subsets and MoDC, and uncovered putative functions of each cell type. Notably, TREM2 hi macrophages appeared to be endowed with specialized functions in lipid metabolism and catabolism, and presented a gene expression signature reminiscent of osteoclasts, suggesting a role in lesion calcification. TREM2 expression was moreover detected in human lesional macrophages. Importantly, these macrophage populations were present also in advanced atherosclerosis and in Apoe -/- aortae, indicating relevance of our findings in different stages of atherosclerosis and mouse models. Conclusions: These data unprecedentedly uncovered the transcriptional landscape and phenotypic

Extracts of Crinum latifolium inhibit the cell viability of mouse lymphoma cell line EL4 and induce activation of anti-tumour activity of macrophages in vitro.

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Nguyen, Hoang-Yen T; Vo, Bach-Hue T; Nguyen, Lac-Thuy H; Bernad, Jose; Alaeddine, Mohamad; Coste, Agnes; Reybier, Karine; Pipy, Bernard; Nepveu, Françoise

2013-08-26

Crinum latifolium L. (CL) leaf extracts have been traditionally used in Vietnam and are now used all over the world for the treatment of prostate cancer. However, the precise cellular mechanisms of the action of CL extracts remain unclear. To examine the effects of CL samples on the anti-tumour activity of peritoneal murine macrophages. The properties of three extracts (aqueous, flavonoid, alkaloid), one fraction (alkaloid), and one pure compound (6-hydroxycrinamidine) obtained from CL, were studied (i) for redox capacities (DPPH and bleaching beta-carotene assays), (ii) on murine peritoneal macrophages (MTT assay) and on lymphoma EL4-luc2 cells (luciferine assay) for cytotoxicity, (iii) on macrophage polarization (production of ROS and gene expression by PCR), and (iv) on the tumoricidal functions of murine peritoneal macrophages (lymphoma cytotoxicity by co-culture with syngeneic macrophages). The total flavonoid extract with a high antioxidant activity (IC50=107.36 mg/L, DPPH assay) showed an inhibitory action on cancer cells. Alkaloid extracts inhibited the proliferation of lymphoma cells either by directly acting on tumour cells or by activating of the tumoricidal functions of syngeneic macrophages. The aqueous extract induced mRNA expression of tumour necrosis factor-α (TNF-α), interleukin-1β (IL-1β) and interleukin 6 (IL-6) indicating differentiation of macrophages into pro-inflammatory M1 polarized macrophages. The total flavonoid, alkaloid extracts and an alkaloid fraction induced the expression of the formyl peptide receptor (FPR) on the surface of the polarized macrophages that could lead to the activation of macrophages towards the M1 phenotype. Aqueous and flavonoid extracts enhanced NADPH quinine oxido-reductase 1 (NQO1) mRNA expression in polarized macrophages which could play an important role in cancer chemoprevention. All the samples studied were non-toxic to normal living cells and the pure alkaloid tested, 6-hydroxycrinamidine, was not

Effect of pecan phenolics on the release of nitric oxide from murine RAW 264.7 macrophage cells.

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Robbins, Katherine S; Greenspan, Phillip; Pegg, Ronald B

2016-12-01

Inflammation is linked to numerous chronic disease states. Phenolic compounds have attracted attention because a number of these compounds possess anti-inflammatory properties. A phenolic crude extract was prepared from pecans and separated by Sephadex LH-20 column chromatography into low- and high-molecular-weight (LMW/HMW) fractions. Anti-inflammatory properties of these fractions were assessed in LPS-stimulated RAW 264.7 murine macrophage cells. NO and reactive oxygen species (ROS) production was monitored after 3 different experimental protocols: (1) pre-treatment with Escherichia coli O111:B4 lipopolysaccharide (LPS); (2) pre-treatment with a pecan crude extract and its fractions; and (3) co-incubation of LPS with a pecan crude extract and its fractions. The LMW fraction displayed a dose-dependent decrease in NO production and a significant decrease from the LPS control in ROS production when cells were either co-incubated with or pre-treated with LPS. The phenolics were characterized by HPLC to help identify those responsible for the observed effect. Copyright © 2016 Elsevier Ltd. All rights reserved.

Pacific ciguatoxin 1B-induced modulation of inflammatory mediators in a murine macrophage cell line.

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Matsui, Mariko; Kumar-Roine, Shilpa; Darius, H Taiana; Chinain, Mireille; Laurent, Dominique; Pauillac, Serge

2010-10-01

Ciguatoxins, potent marine neurotoxins responsible for ciguatera, exert their numerous damaging effects through primary binding to the voltage-sensitive sodium channels of excitable cells. Using RAW 264.7 murine macrophages, we report the first experimental study presenting evidence that P-CTX-1B (the most potent congener from the Pacific) could modulate mRNA expression of pro- and anti-inflammatory cytokines as well as of inducible nitric oxide synthase (iNOS). P-CTX-1B, unlike other less potent marine polyether toxins, P-CTX-3C and PbTx-3, induced the overexpression of interleukin (IL)-1beta, IL-6, IL-10, tumor necrosis factor-alpha and iNOS with different magnitude and kinetic profiles, as compared to bacterial lipopolysaccharide (LPS). Unlike LPS, P-CTX-1B did not modulate IL-11 expression. In this report, we provide new evidence of the P-CTX-1B iNOS- and cytokines-inducing ability and shed new light on host response to potent neurotoxins. Copyright 2009 Elsevier Ltd. All rights reserved.

Glycyrrhizic Acid Promotes M1 Macrophage Polarization in Murine Bone Marrow-Derived Macrophages Associated with the Activation of JNK and NF-κB.

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Mao, Yulong; Wang, Baikui; Xu, Xin; Du, Wei; Li, Weifen; Wang, Youming

2015-01-01

The roots and rhizomes of Glycyrrhiza species (licorice) have been widely used as natural sweeteners and herbal medicines. The aim of this study is to investigate the effect of glycyrrhizic acid (GA) from licorice on macrophage polarization. Both phenotypic and functional activities of murine bone marrow-derived macrophages (BMDMs) treated by GA were assessed. Our results showed that GA obviously increased the cell surface expression of CD80, CD86, and MHCII molecules. Meanwhile, GA upregulated the expression of CCR7 and the production of TNF-α, IL-12, IL-6, and NO (the markers of classically activated (M1) macrophages), whereas it downregulated the expression of MR, Ym1, and Arg1 (the markers of alternatively activated (M2) macrophage). The functional tests showed that GA dramatically enhanced the uptake of FITC-dextran and E. coli K88 by BMDMs and decreased the intracellular survival of E. coli K88 and S. typhimurium. Moreover, we demonstrated that JNK and NF-κB activation are required for GA-induced NO and M1-related cytokines production, while ERK1/2 pathway exhibits a regulatory effect via induction of IL-10. Together, these findings indicated that GA promoted polarization of M1 macrophages and enhanced its phagocytosis and bactericidal capacity. The results expanded our knowledge about the role of GA in macrophage polarization.

Proteomic Analysis Reveals Distinct Metabolic Differences Between Granulocyte-Macrophage Colony Stimulating Factor (GM-CSF) and Macrophage Colony Stimulating Factor (M-CSF) Grown Macrophages Derived from Murine Bone Marrow Cells.

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Na, Yi Rang; Hong, Ji Hye; Lee, Min Yong; Jung, Jae Hun; Jung, Daun; Kim, Young Won; Son, Dain; Choi, Murim; Kim, Kwang Pyo; Seok, Seung Hyeok

2015-10-01

Macrophages are crucial in controlling infectious agents and tissue homeostasis. Macrophages require a wide range of functional capabilities in order to fulfill distinct roles in our body, one being rapid and robust immune responses. To gain insight into macrophage plasticity and the key regulatory protein networks governing their specific functions, we performed quantitative analyses of the proteome and phosphoproteome of murine primary GM-CSF and M-CSF grown bone marrow derived macrophages (GM-BMMs and M-BMMs, respectively) using the latest isobaric tag based tandem mass tag (TMT) labeling and liquid chromatography-tandem mass spectrometry (LC-MS/MS). Strikingly, metabolic processes emerged as a major difference between these macrophages. Specifically, GM-BMMs show significant enrichment of proteins involving glycolysis, the mevalonate pathway, and nitrogen compound biosynthesis. This evidence of enhanced glycolytic capability in GM-BMMs is particularly significant regarding their pro-inflammatory responses, because increased production of cytokines upon LPS stimulation in GM-BMMs depends on their acute glycolytic capacity. In contrast, M-BMMs up-regulate proteins involved in endocytosis, which correlates with a tendency toward homeostatic functions such as scavenging cellular debris. Together, our data describes a proteomic network that underlies the pro-inflammatory actions of GM-BMMs as well as the homeostatic functions of M-BMMs. © 2015 by The American Society for Biochemistry and Molecular Biology, Inc.

A method for generation of bone marrow-derived macrophages from cryopreserved mouse bone marrow cells.

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Fernanda M Marim

Full Text Available The broad use of transgenic and gene-targeted mice has established bone marrow-derived macrophages (BMDM as important mammalian host cells for investigation of the macrophages biology. Over the last decade, extensive research has been done to determine how to freeze and store viable hematopoietic human cells; however, there is no information regarding generation of BMDM from frozen murine bone marrow (BM cells. Here, we establish a highly efficient protocol to freeze murine BM cells and further generate BMDM. Cryopreserved murine BM cells maintain their potential for BMDM differentiation for more than 6 years. We compared BMDM obtained from fresh and frozen BM cells and found that both are similarly able to trigger the expression of CD80 and CD86 in response to LPS or infection with the intracellular bacteria Legionella pneumophila. Additionally, BMDM obtained from fresh or frozen BM cells equally restrict or support the intracellular multiplication of pathogens such as L. pneumophila and the protozoan parasite Leishmania (L. amazonensis. Although further investigation are required to support the use of the method for generation of dendritic cells, preliminary experiments indicate that bone marrow-derived dendritic cells can also be generated from cryopreserved BM cells. Overall, the method described and validated herein represents a technical advance as it allows ready and easy generation of BMDM from a stock of frozen BM cells.

Effects of oxaliplatin and oleic acid Gc-protein-derived macrophage-activating factor on murine and human microglia.

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Branca, Jacopo J V; Morucci, Gabriele; Malentacchi, Francesca; Gelmini, Stefania; Ruggiero, Marco; Pacini, Stefania

2015-09-01

The biological properties and characteristics of microglia in rodents have been widely described, but little is known about these features in human microglia. Several murine microglial cell lines are used to investigate neurodegenerative and neuroinflammatory conditions; however, the extrapolation of the results to human conditions is frequently met with criticism because of the possibility of species-specific differences. This study compares the effects of oxaliplatin and of oleic acid Gc-protein-derived macrophage-activating factor (OA-GcMAF) on two microglial cell lines, murine BV-2 cells and human C13NJ cells. Cell viability, cAMP levels, microglial activation, and vascular endothelial growth factor (VEGF) expression were evaluated. Our data demonstrate that oxaliplatin induced a significant decrease in cell viability in BV-2 and in C13NJ cells and that this effect was not reversed with OA-GcMAF treatment. The signal transduction pathway involving cAMP/VEGF was activated after treatment with oxaliplatin and/or OA-GcMAF in both cell lines. OA-GcMAF induced a significant increase in microglia activation, as evidenced by the expression of the B7-2 protein, in BV-2 as well as in C13NJ cells that was not associated with a concomitant increase in cell number. Furthermore, the effects of oxaliplatin and OA-GcMAF on coculture morphology and apoptosis were evaluated. Oxaliplatin-induced cell damage and apoptosis were nearly completely reversed by OA-GcMAF treatment in both BV-2/SH-SY5Y and C13NJ/SH-SY5Y cocultures. Our data show that murine and human microglia share common signal transduction pathways and activation mechanisms, suggesting that the murine BV-2 cell line may represent an excellent model for studying human microglia. © 2015 Wiley Periodicals, Inc.

5-Lipoxygenase contributes to PPARγ activation in macrophages in response to apoptotic cells.

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von Knethen, Andreas; Sha, Lisa K; Kuchler, Laura; Heeg, Annika K; Fuhrmann, Dominik; Heide, Heinrich; Wittig, Ilka; Maier, Thorsten J; Steinhilber, Dieter; Brüne, Bernhard

2013-12-01

Macrophage polarization to an anti-inflammatory phenotype upon contact with apoptotic cells is a contributing hallmark to immune suppression during the late phase of sepsis. Although the peroxisome proliferator-activated receptor γ (PPARγ) supports this macrophage phenotype switch, it remains elusive how apoptotic cells activate PPARγ. Assuming that a molecule causing PPARγ activation in macrophages originates in the cell membrane of apoptotic cells we analyzed lipid rafts from apoptotic, necrotic, and living human Jurkat T cells which showed the presence of 5-lipoxygenase (5-LO) in lipid rafts of apoptotic cells only. Incubating macrophages with lipid rafts of apoptotic, but not necrotic or living cells, induced PPAR responsive element (PPRE)-driven mRuby reporter gene expression in RAW 264.7 macrophages stably transduced with a 4xPPRE containing vector. Experiments with lipid rafts of apoptotic murine EL4 T cells revealed similar results. To verify the involvement of 5-LO in activating PPARγ in macrophages, Jurkat T cells were incubated with the 5-LO inhibitor MK-866 prior to induction of apoptosis, which failed to induce mRuby expression. Similar results were obtained with lipid rafts of apoptotic EL4 T cells preexposed to the 5-LO inhibitors zileuton and CJ-13610. Interestingly, Jurkat T cells overexpressing 5-LO failed to activate PPARγ in macrophages, while their 5-LO overexpressing apoptotic counterparts did. Our results suggest that during apoptosis 5-LO gets associated with lipid rafts and synthesizes ligands that in turn stimulate PPARγ in macrophages. © 2013.

Anti-inflammatory Potential of Petiveria alliacea on Activated RAW264.7 Murine Macrophages.

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Gutierrez, Rosa Martha Perez; Hoyo-Vadillo, Carlos

2017-07-01

Defense and protection to multiple harmful stimuli are the inflammation, when is self-amplified and uncontrolled is the basis of the pathogenesis of a wide variety of inflammatory illness. The aim of this study was to evaluate if Petiveria alliacea could attenuate inflammation in a murine model of RAW264 macrophages the involved model and its involved mechanism. The ethanol extract from P. alliacea was precipitated with water and supernatant was used for this study (PW). The anti-inflammatory effects of PW were investigated through evaluating of the production of several cytokines, chemokines, and expression of nuclear factor-kappa B (NF-κB) in lipopolysaccharide (LPS)-stimulated RAW264.7 macrophages. Also was determined the ability to decrease the oxidative stress in RAW264.7 cells with carboxy-2',7'-dichloro-dihydro-fluorescein diacetate. PW significantly suppress the secretion of prostaglandin E 2 , leukotriene C 4 , interleukin (IL)-1 β, IL-6, IL-10, interferon gamma nitric oxide (NO), inducible NO synthase, IL-1 β, IL-4, in RAW264.7 cells in a dose-dependent manner. In addition, PW also markedly inhibited the transcriptional activity of NF-κB. PW produced significant anti-inflammatory activity through inhibiting the production of inflammatory mediators through the NF-κB inactivation in the LPS-stimulated RAW24.7 cells. PW exerts significant antioxidant and anti-inflammatory activities, and this effect can be attributed in part, to the presence of dibenzyl disulfide, dibenzyl trisulfide pinitol, coumarin, myricetin, glutamyl-S-benzyl cysteine, and petiveriins A and B. Treatment with ethanol extract from Petiveria alliacea which was previously precipitated with water and supernatant (PE) was tested in LPS-stimulated RAW264.7 cells. PE suppressed the level of oxidative stress and the induction of proinflammatory mediators, as PGE2, LTC4, IL-1 ß, IL-6, IL-10, IFN- NO, iNOS, IL-1 ß, IL-4, in RAW264.7 macrophages through NF-B inactivation. These findings

Flow cytometric quantification of radiation responses of murine peritoneal cells

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Tokita, N.; Raju, M.R.

1982-01-01

Methods have been developed to distinguish subpopulations of murine peritoneal cells, and these were applied to the measurement of early changes in peritoneal cells after irradiation. The ratio of the two major subpopulations in the peritoneal fluid, lymphocytes and macrophages, was measured rapidly by means of cell volume distribution analysis as well as by hypotonic propidium iodide (PI) staining. After irradiation, dose and time dependent changes were noted in the cell volume distributions: a rapid loss of peritoneal lymphocytes, and an increase in the mean cell volume of macrophages. The hypotonic PI staining characteristics of the peritoneal cells showed two or three distinctive G 1 peaks. The ratio of the areas of these peaks was also found to be dependent of the radiation dose and the time after irradiation. These results demonstrate that these two parameters may be used to monitor changes induced by irradiation (biological dosimetry), and to sort different peritoneal subpopulations

IL33 Promotes Colon Cancer Cell Stemness via JNK Activation and Macrophage Recruitment

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Fang, Min; Li, Yongkui; Huang, Kai; Qi, Shanshan; Zhang, Jian; Zgodzinski, Witold; Majewski, Marek; Wallner, Grzegorz; Gozdz, Stanislaw; Macek, Pawel; Kowalik, Artur; Pasiarski, Marcin; Grywalska, Ewelina; Vatan, Linda; Nagarsheth, Nisha; Li, Wei; Zhao, Lili; Kryczek, Ilona; Wang, Guobin; Wang, Zheng; Zou, Weiping; Wang, Lin

2018-01-01

The expression and biological role of IL33 in colon cancer is poorly understood. In this study, we show that IL33 is expressed by vascular endothelial cells and tumor cells in the human colon cancer microenvironment. Administration of human IL33 and overexpression of murine IL33 enhanced human and murine colon cancer cell growth in vivo, respectively. IL33 stimulated cell sphere formation and prevented chemotherapy-induced tumor apoptosis. Mechanistically, IL33 activated core stem cell genes NANOG, NOTCH3, and OCT3/4 via the ST2 signaling pathway, and induced phosphorylation of c-Jun N terminal kinase (JNK) activation and enhanced binding of c-Jun to the promoters of the core stem cell genes. Moreover, IL33 recruited macrophages into the cancer microenvironment and stimulated them to produce prostaglandin E2, which supported colon cancer stemness and tumor growth. Clinically, tumor IL33 expression associated with poor survival in patients with metastatic colon cancer. Thus, IL33 dually targets tumor cells and macrophages and endows stem-like qualities to colon cancer cells to promote carcinogenesis. Collectively, our work reveals an immune-associated mechanism that extrinsically confers cancer cell stemness properties. Targeting the IL33 signaling pathway may offer an opportunity to treat patients with metastatic cancer. PMID:28249897

Asbestos Induces Oxidative Stress and Activation of Nrf2 Signaling in Murine Macrophages: Chemopreventive Role of the Synthetic Lignan Secoisolariciresinol Diglucoside (LGM2605

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Ralph A. Pietrofesa

2016-03-01

Full Text Available The interaction of asbestos fibers with macrophages generates harmful reactive oxygen species (ROS and subsequent oxidative cell damage that are key processes linked to malignancy. Secoisolariciresinol diglucoside (SDG is a non-toxic, flaxseed-derived pluripotent compound that has antioxidant properties and may thus function as a chemopreventive agent for asbestos-induced mesothelioma. We thus evaluated synthetic SDG (LGM2605 in asbestos-exposed, elicited murine peritoneal macrophages as an in vitro model of tissue phagocytic response to the presence of asbestos in the pleural space. Murine peritoneal macrophages (MFs were exposed to crocidolite asbestos fibers (20 µg/cm2 and evaluated at various times post exposure for cytotoxicity, ROS generation, malondialdehyde (MDA, and levels of 8-iso Prostaglandin F2α (8-isoP. We then evaluated the ability of LGM2605 to mitigate asbestos-induced oxidative stress by administering LGM2605 (50 µM 4-h prior to asbestos exposure. We observed a significant (p < 0.0001, time-dependent increase in asbestos-induced cytotoxicity, ROS generation, and the release of MDA and 8-iso Prostaglandin F2α, markers of lipid peroxidation, which increased linearly over time. LGM2605 treatment significantly (p < 0.0001 reduced asbestos-induced cytotoxicity and ROS generation, while decreasing levels of MDA and 8-isoP by 71%–88% and 41%–73%, respectively. Importantly, exposure to asbestos fibers induced cell protective defenses, such as cellular Nrf2 activation and the expression of phase II antioxidant enzymes, HO-1 and Nqo1 that were further enhanced by LGM2605 treatment. LGM2605 boosted antioxidant defenses, as well as reduced asbestos-induced ROS generation and markers of oxidative stress in murine peritoneal macrophages, supporting its possible use as a chemoprevention agent in the development of asbestos-induced malignant mesothelioma.

Tumor cell-derived microparticles polarize M2 tumor-associated macrophages for tumor progression.

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Ma, Ruihua; Ji, Tiantian; Chen, Degao; Dong, Wenqian; Zhang, Huafeng; Yin, Xiaonan; Ma, Jingwei; Liang, Xiaoyu; Zhang, Yi; Shen, Guanxin; Qin, Xiaofeng; Huang, Bo

2016-04-01

Despite identification of macrophages in tumors (tumor-associated macrophages, TAM) as potential targets for cancer therapy, the origin and function of TAM in the context of malignancy remain poorly characterized. Here, we show that microparticles (MPs), as a by-product, released by tumor cells act as a general mechanism to mediate M2 polarization of TAM. Taking up tumor MPs by macrophages is a very efficient process, which in turn results in the polarization of macrophages into M2 type, not only leading to promoting tumor growth and metastasis but also facilitating cancer stem cell development. Moreover, we demonstrate that the underlying mechanism involves the activation of the cGAS/STING/TBK1/STAT6 pathway by tumor MPs. Finally, in addition to murine tumor MPs, we show that human counterparts also possess consistent effect on human M2 polarization. These findings provide new insights into a critical role of tumor MPs in remodeling of tumor microenvironment and better understanding of the communications between tumors and macrophages.

Effect of azithromycin on Prevotella intermedia lipopolysaccharide-induced production of interleukin-6 in murine macrophages.

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Choi, Eun-Young; Jin, Ji-Young; Choi, Jeom-Il; Choi, In Soon; Kim, Sung-Jo

2014-04-15

Interleukin-6 (IL-6) is a key proinflammatory cytokine which plays a central role in the pathogenesis of periodontal disease. Host modulatory agents targeting at inhibiting IL-6, therefore, appear to be beneficial in slowing the progression of periodontal disease and potentially reducing destructive aspects of the host response. The present study was designed to investigate the effect of the macrolide antibiotic azithromycin on IL-6 generation in murine macrophages treated with lipopolysaccharide (LPS) from Prevotella intermedia, a pathogen implicated in inflammatory periodontal disease, and its mechanisms of action. Azithromycin significantly suppressed IL-6 production as well as its mRNA expression in P. intermedia LPS-activated RAW264.7 cells. LPS-induced activation of JNK and p38 was not affected by azithromycin treatment. Azithromycin failed to prevent P. intermedia LPS from degrading IκB-α. Instead, azithromycin significantly diminished nuclear translocation and DNA binding activity of NF-κB p50 subunit induced with LPS. Azithromycin inhibited P. intermedia LPS-induced STAT1 and STAT3 phosphorylation. In addition, azithromycin up-regulated the mRNA level of SOCS1 in cells treated with LPS. In conclusion, azithromycin significantly attenuated P. intermedia LPS-induced production of IL-6 in murine macrophages via inhibition of NF-κB, STAT1 and STAT3 activation, which is possibly related to the activation of SOCS1 signaling. Further in vivo studies are required to better evaluate the potential of azithromycin in the treatment of periodontal disease. Copyright © 2014 Elsevier B.V. All rights reserved.

Reprogramming of murine macrophages through TLR2 confers viral resistance via TRAF3-mediated, enhanced interferon production.

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Darren J Perkins

Full Text Available The cell surface/endosomal Toll-like Receptors (TLRs are instrumental in initiating immune responses to both bacteria and viruses. With the exception of TLR2, all TLRs and cytosolic RIG-I-like receptors (RLRs with known virus-derived ligands induce type I interferons (IFNs in macrophages or dendritic cells. Herein, we report that prior ligation of TLR2, an event previously shown to induce "homo" or "hetero" tolerance, strongly "primes" macrophages for increased Type I IFN production in response to subsequent TLR/RLR signaling. This occurs by increasing activation of the transcription factor, IFN Regulatory Factor-3 (IRF-3 that, in turn, leads to enhanced induction of IFN-β, while expression of other pro-inflammatory genes are suppressed (tolerized. In vitro or in vivo "priming" of murine macrophages with TLR2 ligands increase virus-mediated IFN induction and resistance to infection. This priming effect of TLR2 is mediated by the selective upregulation of the K63 ubiquitin ligase, TRAF3. Thus, we provide a mechanistic explanation for the observed antiviral actions of MyD88-dependent TLR2 and further define the role of TRAF3 in viral innate immunity.

Cells of the J774 macrophage cell line are primed for antibody-dependent cell-mediated cytotoxicity following exposure to γ-irradiation

International Nuclear Information System (INIS)

Duerst, R.; Werberig, K.

1991-01-01

Activation of macrophages (M phi) for host defense against tumor cells follows a sequence of priming events followed by an initiating stimulus that results in production and release of cytotoxic molecules that mediate target cell killing. The authors have developed a model to study specific macrophage cytotoxicity in vitro utilizing a cultured murine M phi cell line, J774. Specific cytotoxicity of cultured human gastrointestinal tumor cells is achieved in the presence of murine IgG2a monoclonal antibody (mAb) 17-1-A. The ability of these cells to mediate antibody-dependent cell-mediated cytotoxicity (ADCC) is greatly enhanced following gamma-irradiation. ADCC can be demonstrated at mAb 17-1-A concentrations greater than or equal to 1 microgram/ml and effector/target cell ratios greater than or equal to 2. Exposure to doses greater than or equal to 10 Gy of gamma-irradiation increases ADCC threefold. Varying the duration from J774 M phi exposure to γ-irradiation until addition of antibody-coated target cells showed that the primed state for ADCC is stable for at least 8 days but approximately 24 hr is required for complete development of the primed state. mAb-dependent target cell death begins 8 hr after addition of mAb and labeled target cells to primed effector cells and is complete by 24 hr. Incubation of unirradiated J774 M phi effector cells with recombinant murine interferon-γ (rmIFN-γ) also results in enhanced ADCC, but the extent of target cell killing achieved is less than that following priming by γ-irradiation. Concomitant priming of γ-irradiated J774 M phi with rmIFN-γ increases the extent of ADCC. Further study of irradiated J774 cells may elucidate the molecular pathways utilized by M phi for achieving and maintaining the primed state for ADCC

Enniatin B-induced cell death and inflammatory responses in RAW 267.4 murine macrophages

Energy Technology Data Exchange (ETDEWEB)

Gammelsrud, A. [Norwegian Veterinary Institute, P.O. Box 750, Centrum, N-0106 Oslo (Norway); Department of Air Pollution and Noise, Division of Environmental Medicine, Norwegian Institute of Public Health, N-0403 Oslo (Norway); Solhaug, A. [Norwegian Veterinary Institute, P.O. Box 750, Centrum, N-0106 Oslo (Norway); Dendelé, B. [EA 4427 SeRAIC, IRSET, Université de Rennes 1, IFR 140, Rennes (France); Sandberg, W.J. [Department of Air Pollution and Noise, Division of Environmental Medicine, Norwegian Institute of Public Health, N-0403 Oslo (Norway); Ivanova, L. [Norwegian Veterinary Institute, P.O. Box 750, Centrum, N-0106 Oslo (Norway); Kocbach Bølling, A. [Department of Air Pollution and Noise, Division of Environmental Medicine, Norwegian Institute of Public Health, N-0403 Oslo (Norway); Lagadic-Gossmann, D. [EA 4427 SeRAIC, IRSET, Université de Rennes 1, IFR 140, Rennes (France); Refsnes, M.; Becher, R. [Department of Air Pollution and Noise, Division of Environmental Medicine, Norwegian Institute of Public Health, N-0403 Oslo (Norway); Eriksen, G. [Norwegian Veterinary Institute, P.O. Box 750, Centrum, N-0106 Oslo (Norway); Holme, J.A., E-mail: jorn.holme@fhi.no [Department of Air Pollution and Noise, Division of Environmental Medicine, Norwegian Institute of Public Health, N-0403 Oslo (Norway)

2012-05-15

The mycotoxin enniatin B (EnnB) is predominantly produced by species of the Fusarium genera, and often found in grain. The cytotoxic effect of EnnB has been suggested to be related to its ability to form ionophores in cell membranes. The present study examines the effects of EnnB on cell death, differentiation, proliferation and pro-inflammatory responses in the murine monocyte–macrophage cell line RAW 264.7. Exposure to EnnB for 24 h caused an accumulation of cells in the G0/G1-phase with a corresponding decrease in cyclin D1. This cell cycle-arrest was possibly also linked to the reduced cellular ability to capture and internalize receptors as illustrated by the lipid marker ganglioside GM1. EnnB also increased the number of apoptotic, early apoptotic and necrotic cells, as well as cells with elongated spindle-like morphology. The Neutral Red assay indicated that EnnB induced lysosomal damage; supported by transmission electron microscopy (TEM) showing accumulation of lipids inside the lysosomes forming lamellar structures/myelin bodies. Enhanced levels of activated caspase-1 were observed after EnnB exposure and the caspase-1 specific inhibitor ZYVAD-FMK reduced EnnB-induced apoptosis. Moreover, EnnB increased the release of interleukin-1beta (IL-1β) in cells primed with lipopolysaccharide (LPS), and this response was reduced by both ZYVAD-FMK and the cathepsin B inhibitor CA-074Me. In conclusion, EnnB was found to induce cell cycle arrest, cell death and inflammation. Caspase-1 appeared to be involved in the apoptosis and release of IL-1β and possibly activation of the inflammasome through lysosomal damage and leakage of cathepsin B. -- Highlights: ► The mycotoxin EnnB induced cell cycle arrest, cell death and inflammation. ► The G0/G1-arrest was linked to a reduced ability to internalize receptors. ► EnnB caused lysosomal damage, leakage of cathepsin B and caspase-1 cleavage. ► Caspase-1 was partly involved in both apoptosis and release of IL-1�

Enniatin B-induced cell death and inflammatory responses in RAW 267.4 murine macrophages

International Nuclear Information System (INIS)

Gammelsrud, A.; Solhaug, A.; Dendelé, B.; Sandberg, W.J.; Ivanova, L.; Kocbach Bølling, A.; Lagadic-Gossmann, D.; Refsnes, M.; Becher, R.; Eriksen, G.; Holme, J.A.

2012-01-01

The mycotoxin enniatin B (EnnB) is predominantly produced by species of the Fusarium genera, and often found in grain. The cytotoxic effect of EnnB has been suggested to be related to its ability to form ionophores in cell membranes. The present study examines the effects of EnnB on cell death, differentiation, proliferation and pro-inflammatory responses in the murine monocyte–macrophage cell line RAW 264.7. Exposure to EnnB for 24 h caused an accumulation of cells in the G0/G1-phase with a corresponding decrease in cyclin D1. This cell cycle-arrest was possibly also linked to the reduced cellular ability to capture and internalize receptors as illustrated by the lipid marker ganglioside GM1. EnnB also increased the number of apoptotic, early apoptotic and necrotic cells, as well as cells with elongated spindle-like morphology. The Neutral Red assay indicated that EnnB induced lysosomal damage; supported by transmission electron microscopy (TEM) showing accumulation of lipids inside the lysosomes forming lamellar structures/myelin bodies. Enhanced levels of activated caspase-1 were observed after EnnB exposure and the caspase-1 specific inhibitor ZYVAD-FMK reduced EnnB-induced apoptosis. Moreover, EnnB increased the release of interleukin-1beta (IL-1β) in cells primed with lipopolysaccharide (LPS), and this response was reduced by both ZYVAD-FMK and the cathepsin B inhibitor CA-074Me. In conclusion, EnnB was found to induce cell cycle arrest, cell death and inflammation. Caspase-1 appeared to be involved in the apoptosis and release of IL-1β and possibly activation of the inflammasome through lysosomal damage and leakage of cathepsin B. -- Highlights: ► The mycotoxin EnnB induced cell cycle arrest, cell death and inflammation. ► The G0/G1-arrest was linked to a reduced ability to internalize receptors. ► EnnB caused lysosomal damage, leakage of cathepsin B and caspase-1 cleavage. ► Caspase-1 was partly involved in both apoptosis and release of IL-1�

Macrophage Reporter Cell Assay for Screening Immunopharmacological Activity of Cell Wall-Active Antifungals

OpenAIRE

Lewis, Russell E.; Liao, Guangling; Young, Katherine; Douglas, Cameron; Kontoyiannis, Dimitrios P.

2014-01-01

Antifungal exposure can elicit immunological effects that contribute to activity in vivo, but this activity is rarely screened in vitro in a fashion analogous to MIC testing. We used RAW 264.7 murine macrophages that express a secreted embryonic alkaline phosphatase (SEAP) gene induced by transcriptional activation of NF-κB and activator protein 1 (AP-1) to develop a screen for immunopharmacological activity of cell wall-active antifungal agents. Isolates of Candida albicans and Aspergillus f...

Peritoneal macrophages mediated delivery of chitosan/siRNA nanoparticle to the lesion site in a murine radiation-induced fibrosis model

DEFF Research Database (Denmark)

Nawroth, Isabel; Alsner, Jan; Deleuran, B.W.

2013-01-01

of chitosan/siRNA nanoparticles directed towards silencing TNF alpha in local macrophage populations, but the mechanism for the therapeutic effect at the lesion site remains unclear. Methods. Using the same murine RIF model we utilized an optical imaging technique and fluorescence microscopy to investigate...... the uptake of chitosan/fluorescently labeled siRNA nanoparticles by peritoneal macrophages and their subsequent migration to the inflamed tissue in the RIF model. Results. We observed strong accumulation of the fluorescent signal in the lesion site of the irradiated leg up to 24 hours using the optical...... imaging system. We further confirm by immunohistochemical staining that Cy3 labeled siRNA resides in macrophages of the irradiated leg. Conclusion. We provide a proof-of-concept for host macrophage trafficking towards the inflamed region in a murine RIF model, which thereby suggests that the chitosan...

Rhizoma Coptidis Inhibits LPS-Induced MCP-1/CCL2 Production in Murine Macrophages via an AP-1 and NF?B-Dependent Pathway

OpenAIRE

Remppis, Andrew; Bea, Florian; Greten, Henry Johannes; Buttler, Annette; Wang, Hongjie; Zhou, Qianxing; Preusch, Michael R.; Enk, Ronny; Ehehalt, Robert; Katus, Hugo; Blessing, Erwin

2010-01-01

Introduction. The Chinese extract Rhizoma coptidis is well known for its anti-inflammatory, antioxidative, antiviral, and antimicrobial activity. The exact mechanisms of action are not fully understood. Methods. We examined the effect of the extract and its main compound, berberine, on LPS-induced inflammatory activity in a murine macrophage cell line. RAW 264.7 cells were stimulated with LPS and incubated with either Rhizoma coptidis extract or berberine. Activation of AP-1 and NFB was anal...

Lewis Lung Cancer Cells Promote SIGNR1(CD209b)-Mediated Macrophages Polarization Induced by IL-4 to Facilitate Immune Evasion.

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Yan, Xiaolong; Li, Wenhai; Pan, Lei; Fu, Enqing; Xie, Yonghong; Chen, Min; Mu, Deguang

2016-05-01

Tumor-associated macrophages are a prominent component of lung cancer and contribute to tumor progression by facilitating the immune evasion of cancer cells. DC-SIGN (CD209) assists in the immune evasion of a broad spectrum of pathogens and neoplasms by inhibiting the maturation of DCs and subsequent cytokines production. However, the expression of DC-SIGN in macrophages and its role in mediating immune evasion in lung cancer and the underlying mechanism remain unclear. Our study aimed to identify the immunosuppressive role of SIGNR1 in murine macrophage differentiation and lung cancer progression. We found that SIGNR1-positive RAW264.7 macrophages were enriched in mixed cultures with Lewis lung cancer cells (LLC) (ratio of RAW 264.7 to LLC being 1:1) after stimulation with IL-4. Moreover, LLC-educated macrophages exhibited significantly higher levels of IL-10 but lower IL-12 in response to IL-4 treatment as determined by RT-PCR and ELISA. However, inhibition of SIGNR1 markedly hampered the production of IL-10, indicating that SIGNR1 was indispensable for IL-4+LLC induced macrophage polarization towards the M2 subtype. Furthermore, polarized M2 cells immersed in a tumor microenvironment promoted the migration of LLCs, as measured by transwell assays, but migration was suppressed after blockade of SIGNR1 using CD209b antibody. In addition, IL-4+LLC-educated macrophages reduced the proliferation of the activated T cells and reduced IFN-γ-mediated Th1 response in T cells, while SIGNR1 inhibition rescued Th1 cell functions. In conclusion, murine SIGNR1 expressed in LLC-educated macrophages appears to mediate IL-4-induced RAW264.7 macrophage polarization and thus facilitate lung cancer evasion. © 2015 Wiley Periodicals, Inc.

Regulation of ICAM-1 in Cells of the Monocyte/Macrophage System in Microgravity

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Katrin Paulsen

2015-01-01

Full Text Available Cells of the immune system are highly sensitive to altered gravity, and the monocyte as well as the macrophage function is proven to be impaired under microgravity conditions. In our study, we investigated the surface expression of ICAM-1 protein and expression of ICAM-1 mRNA in cells of the monocyte/macrophage system in microgravity during clinostat, parabolic flight, sounding rocket, and orbital experiments. In murine BV-2 microglial cells, we detected a downregulation of ICAM-1 expression in clinorotation experiments and a rapid and reversible downregulation in the microgravity phase of parabolic flight experiments. In contrast, ICAM-1 expression increased in macrophage-like differentiated human U937 cells during the microgravity phase of parabolic flights and in long-term microgravity provided by a 2D clinostat or during the orbital SIMBOX/Shenzhou-8 mission. In nondifferentiated U937 cells, no effect of microgravity on ICAM-1 expression could be observed during parabolic flight experiments. We conclude that disturbed immune function in microgravity could be a consequence of ICAM-1 modulation in the monocyte/macrophage system, which in turn could have a strong impact on the interaction with T lymphocytes and cell migration. Thus, ICAM-1 can be considered as a rapid-reacting and sustained gravity-regulated molecule in mammalian cells.

Bacterial lipopolysaccharide induces osteoclast formation in RAW 264.7 macrophage cells

International Nuclear Information System (INIS)

Islam, Shamima; Hassan, Ferdaus; Tumurkhuu, Gantsetseg; Dagvadorj, Jargalsaikhan; Koide, Naoki; Naiki, Yoshikazu; Mori, Isamu; Yoshida, Tomoaki; Yokochi, Takashi

2007-01-01

Lipopolysaccharide (LPS) is a potent bone resorbing factor. The effect of LPS on osteoclast formation was examined by using murine RAW 264.7 macrophage cells. LPS-induced the formation of multinucleated giant cells (MGC) in RAW 264.7 cells 3 days after the exposure. MGCs were positive for tartrate-resistant acid phosphatase (TRAP) activity. Further, MGC formed resorption pits on calcium-phosphate thin film that is a substrate for osteoclasts. Therefore, LPS was suggested to induce osteoclast formation in RAW 264.7 cells. LPS-induced osteoclast formation was abolished by anti-tumor necrosis factor (TNF)-α antibody, but not antibodies to macrophage-colony stimulating factor (M-CSF) and receptor activator of nuclear factor (NF)-κB ligand (RANKL). TNF-α might play a critical role in LPS-induced osteoclast formation in RAW 264.7 cells. Inhibitors of NF-κB and stress activated protein kinase (SAPK/JNK) prevented the LPS-induced osteoclast formation. The detailed mechanism of LPS-induced osteoclast formation is discussed

Quantitative measurements of intercellular adhesion between a macrophage and cancer cells using a cup-attached AFM chip.

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Kim, Hyonchol; Yamagishi, Ayana; Imaizumi, Miku; Onomura, Yui; Nagasaki, Akira; Miyagi, Yohei; Okada, Tomoko; Nakamura, Chikashi

2017-07-01

Intercellular adhesion between a macrophage and cancer cells was quantitatively measured using atomic force microscopy (AFM). Cup-shaped metal hemispheres were fabricated using polystyrene particles as a template, and a cup was attached to the apex of the AFM cantilever. The cup-attached AFM chip (cup-chip) approached a murine macrophage cell (J774.2), the cell was captured on the inner concave of the cup, and picked up by withdrawing the cup-chip from the substrate. The cell-attached chip was advanced towards a murine breast cancer cell (FP10SC2), and intercellular adhesion between the two cells was quantitatively measured. To compare cell adhesion strength, the work required to separate two adhered cells (separation work) was used as a parameter. Separation work was almost 2-fold larger between a J774.2 cell and FP10SC2 cell than between J774.2 cell and three additional different cancer cells (4T1E, MAT-LyLu, and U-2OS), two FP10SC2 cells, or two J774.2 cells. FP10SC2 was established from 4T1E as a highly metastatic cell line, indicates separation work increased as the malignancy of cancer cells became higher. One possible explanation of the strong adhesion of macrophages to cancer cells observed in this study is that the measurement condition mimicked the microenvironment of tumor-associated macrophages (TAMs) in vivo, and J774.2 cells strongly expressed CD204, which is a marker of TAMs. The results of the present study, which were obtained by measuring cell adhesion strength quantitatively, indicate that the fabricated cup-chip is a useful tool for measuring intercellular adhesion easily and quantitatively. Copyright © 2017 Elsevier B.V. All rights reserved.

Regulation of endothelial cell adhesion molecule expression by mast cells, macrophages, and neutrophils.

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Jie Zhang

2011-01-01

Full Text Available Leukocyte adhesion to the vascular endothelium and subsequent transendothelial migration play essential roles in the pathogenesis of cardiovascular diseases such as atherosclerosis. The leukocyte adhesion is mediated by localized activation of the endothelium through the action of inflammatory cytokines. The exact proinflammatory factors, however, that activate the endothelium and their cellular sources remain incompletely defined.Using bone marrow-derived mast cells from wild-type, Tnf(-/-, Ifng(-/-, Il6(-/- mice, we demonstrated that all three of these pro-inflammatory cytokines from mast cells induced the expression of vascular cell adhesion molecule-1 (VCAM-1, intercellular adhesion molecule-1 (ICAM-1, P-selectin, and E-selectin in murine heart endothelial cells (MHEC at both mRNA and protein levels. Compared with TNF-α and IL6, IFN-γ appeared weaker in the induction of the mRNA levels, but at protein levels, both IL6 and IFN-γ were weaker inducers than TNF-α. Under physiological shear flow conditions, mast cell-derived TNF-α and IL6 were more potent than IFN-γ in activating MHEC and in promoting neutrophil adhesion. Similar observations were made when neutrophils or macrophages were used. Neutrophils and macrophages produced the same sets of pro-inflammatory cytokines as did mast cells to induce MHEC adhesion molecule expression, with the exception that macrophage-derived IFN-γ showed negligible effect in inducing VCAM-1 expression in MHEC.Mast cells, neutrophils, and macrophages release pro-inflammatory cytokines such as TNF-α, IFN-γ, and IL6 that induce expression of adhesion molecules in endothelium and recruit of leukocytes, which is essential to the pathogenesis of vascular inflammatory diseases.

Development and characterization of antiserum to murine granulocyte-macrophage colony-stimulating factor

International Nuclear Information System (INIS)

Mochizuki, D.Y.; Eisenman, J.R.; Conlon, P.J.; Park, L.S.; Urdal, D.L.

1986-01-01

The expression in yeast of a cDNA clone encoding murine granulocyte-macrophage colony-stimulating factor (GM-CSF) has made possible the purification of large quantities of this recombinant protein. Rabbits immunized with pure recombinant GM-CSF generated antibodies that were shown to be specific for both recombinant GM-CSF and GM-CSF isolated from natural sources. Other lymphokines, including IL 1β, IL 2, IL 3, and recombinant human GM-CSF did not react with the antiserum. The antiserum together with recombinant GM-CSF that had been radiolabeled with 125 I to high specific activity, formed the foundation for a rapid, sensitive, and quantitative radioimmunoassay specific for murine GM-CSF. Furthermore, the antiserum was found to inhibit the biologic activities of GM-CSF as measured in both a bone marrow proliferation assay and a colony assay, and thus should prove to be a useful reagent for dissecting the complex growth factor activities involved in murine hematopoiesis

The Poly-γ-D-Glutamic Acid Capsule of Bacillus licheniformis, a Surrogate of Bacillus anthracis Capsule Induces Interferon-Gamma Production in NK Cells through Interactions with Macrophages.

Science.gov (United States)

Lee, Hae-Ri; Jeon, Jun Ho; Rhie, Gi-Eun

2017-05-28

The poly-γ- D -glutamic acid (PGA) capsule, a major virulence factor of Bacillus anthracis , provides protection of the bacterium from phagocytosis and allows its unimpeded growth in the host. We investigated crosstalk between murine natural killer (NK) cells and macrophages stimulated with the PGA capsule of Bacillus licheniformis , a surrogate of the B. anthracis capsule. PGA induced interferon-gamma production from NK cells cultured with macrophages. This effect was dependent on macrophage-derived IL-12 and cell-cell contact interaction with macrophages through NK cell receptor NKG2D and its ligand RAE-1. The results showed that PGA could enhance NK cell activation by inducing IL-12 production in macrophages and a contact-dependent crosstalk with macrophages.

Effect of quercetin on the production of nitric oxide in murine macrophages stimulated with lipopolysaccharide from Prevotella intermedia.

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Cho, Yun-Jung; Kim, Sung-Jo

2013-08-01

Nitric oxide (NO) is a short-lived bioactive molecule that is known to play an important role in the pathogenesis of periodontal disease. In the current study, we investigated the effect of the flavonoid quercetin on the production of NO in murine macrophages activated with lipopolysaccharide (LPS) from Prevotella intermedia, a pathogen related to inflammatory periodontal disease, and tried to elucidate the underlying mechanisms of action. LPS was isolated from P. intermedia ATCC 25611 cells by the standard hot phenol-water method. The concentration of NO in cell culture supernatants was determined by measuring the accumulation of nitrite. Inducible NO synthase (iNOS) and heme oxygenase-1 (HO-1) protein expression, phosphorylation of c-Jun N-terminal kinase (JNK) and p38, inhibitory κB (IκB)-α degradation, and signal transducer and activator of transcription 1 (STAT1) phosphorylation were analyzed via immunoblotting. Quercetin significantly attenuated iNOS-derived NO production in RAW246.7 cells activated by P. intermedia LPS. In addition, quercetin induced HO-1 protein expression in cells activated with P. intermedia LPS. Tin protoporphyrin IX (SnPP), a competitive inhibitor of HO-1, abolished the inhibitory effect of quercetin on LPS-induced NO production. Quercetin did not affect the phosphorylation of JNK and p38 induced by P. intermedia LPS. The degradation of IκB-α induced by P. intermedia LPS was inhibited when the cells were treated with quercetin. Quercetin also inhibited LPS-induced STAT1 signaling. Quercetin significantly inhibits iNOS-derived NO production in murine macrophages activated by P. intermedia LPS via anti-inflammatory HO-1 induction and inhibition of the nuclear factor-κB and STAT1 signaling pathways. Our study suggests that quercetin may contribute to the modulation of host-destructive responses mediated by NO and appears to have potential as a novel therapeutic agent for treating inflammatory periodontal disease.

Taheebo Polyphenols Attenuate Free Fatty Acid-Induced Inflammation in Murine and Human Macrophage Cell Lines As Inhibitor of Cyclooxygenase-2

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Sihui Ma

2017-12-01

Full Text Available Aim of studyTaheebo polyphenols (TP are water extracts of Tabebuia spp. (Bignoniaceae, taken from the inner bark of the Tabebuia avellanedae tree, used extensively as folk medicine in Central and South America. Some anti-inflammatory drugs act by inhibiting both cyclooxygenase-2 (COX-2 and COX-1 enzymes. COX-2 syntheses prostaglandin (PG E2, which is a species of endogenous pain-producing substance, whereas COX-1 acts as a house-keeping enzyme. Inhibiting both COX-1 and -2 simultaneously can have side effects such as gastrointestinal bleeding and renal dysfunction. Some polyphenols have been reported for its selective inhibiting activity toward COX-2 expression. Our study aimed to demonstrate the potential and mechanisms of TP as an anti-inflammation action without the side effects of COX-1 inhibition.Materials and methodsFree fatty acid-stimulated macrophage cell lines were employed to mimic macrophage behaviors during lifestyle-related diseases such as atherosclerosis and non-alcoholic steatohepatitis. Real-time polymerase chain reaction was used to detect expression of inflammatory cytokine mRNA. Griess assay was used to measure the production of nitric oxide (NO. ELISA was used to measure PG E2 production. Molecular docking was adopted to analyze the interactions between compounds from T. avellanedae and COX-2.ResultsTP significantly suppressed the production of NO production, blocked the mRNA expression of iNOS, and COX-2 in both cell lines, blocked the mRNA expression of TNF-α, IL-1β, IL-6, and PGE2 in the murine cell line. However, there was no inhibitory effect on COX-1. Molecular docking result indicated that the inhibitory effects of TP on COX-2 and PGE2 could be attributed to acteoside, which is the main compound of TP that could bind to the catalytic zone of COX-2. After the interaction, catalytic ability of COX-2 is possibly inhibited, followed by which PGE2 production is attenuated. COX inhibitor screening assay showed TP as a

Modified pectin from Theobroma cacao induces potent pro-inflammatory activity in murine peritoneal macrophage.

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Amorim, Juliana C; Vriesmann, Lucia Cristina; Petkowicz, Carmen L O; Martinez, Glaucia Regina; Noleto, Guilhermina R

2016-11-01

In vitro effects of acetylated pectin (OP) isolated from cacao pod husks (Theobroma cacao L.), its partially deacetylated and de-esterified form (MOP), and a commercial homogalacturonan (PG) were investigated on murine peritoneal macrophages. MOP stood out among the studied pectins. After 48h of incubation, compared with the control group, it was able to promote significant macrophage morphological differentiation from resident to activated stage and also stimulated nitric oxide production, which reached a level of 85% of that of LPS stimulus. In the presence of the highest tested concentration of MOP (200μg·mL -1 ), the levels of the cytokines TNF-α (6h) and IL-12 and IL-10 (48h) increased substantially in relation to untreated cells. Our results show that the partial deacetylation and de-esterification of pectin extracted from cacao pod husks (T. cacao L.) produced a polymer with greater ability than its native form to activate macrophages to a cytotoxic phenotype. Like this, they provide the possibility of a therapeutic application to MOP, which could lead to a decreased susceptibility to microbial infection besides antitumor activity. Additionally, the present results also corroborate with the proposition of that the chemical modifications of the biopolymers can result in an improved molecule with new possibilities of application. Copyright © 2016 Elsevier B.V. All rights reserved.

Regulation of adhesion behavior of murine macrophage using supported lipid membranes displaying tunable mannose domains

International Nuclear Information System (INIS)

Kaindl, T; Oelke, J; Kaufmann, S; Tanaka, M; Pasc, A; Konovalov, O V; Funari, S S; Engel, U; Wixforth, A

2010-01-01

Highly uniform, strongly correlated domains of synthetically designed lipids can be incorporated into supported lipid membranes. The systematic characterization of membranes displaying a variety of domains revealed that the equilibrium size of domains significantly depends on the length of fluorocarbon chains, which can be quantitatively interpreted within the framework of an equivalent dipole model. A mono-dispersive, narrow size distribution of the domains enables us to treat the inter-domain correlations as two-dimensional colloidal crystallization and calculate the potentials of mean force. The obtained results demonstrated that both size and inter-domain correlation can precisely be controlled by the molecular structures. By coupling α-D-mannose to lipid head groups, we studied the adhesion behavior of the murine macrophage (J774A.1) on supported membranes. Specific adhesion and spreading of macrophages showed a clear dependence on the density of functional lipids. The obtained results suggest that such synthetic lipid domains can be used as a defined platform to study how cells sense the size and distribution of functional molecules during adhesion and spreading.

Splenectomy attenuates murine liver fibrosis with hypersplenism stimulating hepatic accumulation of Ly-6C(lo) macrophages.

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Yada, Akito; Iimuro, Yuji; Uyama, Naoki; Uda, Yugo; Okada, Toshihiro; Fujimoto, Jiro

2015-10-01

Splenectomy in cirrhotic patients has been reported to improve liver function; however the underlying mechanism remains obscure. In the present study, we investigated the mechanism using a murine model, which represents well the compensated liver cirrhosis. C57BL/6 male mice were allowed to drink water including thioacetamide (TAA: 300 mg/L) ad libitum for 32 weeks. After splenectomy at 32 weeks, mice were sacrificed on days one, seven, and 28, respectively, while TAA-administration was continued. Perioperative changes in peripheral blood and liver tissues were analyzed. TAA treatment of mice for 32 weeks reproducibly achieved advanced liver fibrosis with splenomegaly, thrombocytopenia, and leukocytopenia. After splenectomy, liver fibrosis was attenuated, and macrophages/monocytes were significantly increased in peripheral blood, as well as in the liver. Progenitor-like cells expressing CK-19, EpCAM, or CD-133 appeared in the liver after TAA treatment, and gradually disappeared after splenectomy. Macrophages/monocytes accumulated in the liver, most of which were negative for Ly-6C, were adjacent to the hepatic progenitor-like cells, and quantitative RT-PCR indicated increased canonical Wnt and decreased Notch signals. As a result, a significant amount of β-catenin accumulated in the progenitor-like cells. Moreover, relatively small Ki67-positive hepatic cells were significantly increased. Protein expression of MMP-9, to which Ly-6G-positive neutrophils contributed, was also increased in the liver after splenectomy. The hepatic accumulation of macrophages/monocytes, most of which are Ly-6C(lo), the reduction of fibrosis, and the gradual disappearance of hepatic progenitor-like cells possibly play significant roles in the tissue remodeling process in cirrhotic livers after splenectomy. Copyright © 2015 European Association for the Study of the Liver. Published by Elsevier B.V. All rights reserved.

F4/80 as a Major Macrophage Marker: The Case of the Peritoneum and Spleen.

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Dos Anjos Cassado, Alexandra

2017-01-01

Tissue macrophages are a heterogeneous cell population residing in all body tissues that contribute to the maintenance of homeostasis and trigger immune activation in response to injurious stimuli. This heterogeneity may be associated with tissue-specific functions; however, the presence of distinct macrophage populations within the same microenvironment indicates that macrophage heterogeneity may also be influenced outside of tissue specialization. The F4/80 molecule was established as a unique marker of murine macrophages when a monoclonal antibody was found to recognize an antigen exclusively expressed by these cells. However, recent research has shown that F4/80 is expressed by other immune cells and is not equivalently expressed across tissue-specific macrophage lineages, including those residing in the same microenvironment, such as the peritoneum and spleen. In this context, two murine macrophage subtypes with distinct F4/80 expression patterns were recently found to coexist in the peritoneum, termed large peritoneal macrophages (LPMs) and small peritoneal macrophages (SPMs). However, the presence of phenotypic and functional heterogeneous macrophage subpopulations in the spleen was already known. Thus, although F4/80 surface expression continues to be the best method to identify tissue macrophages, additional molecules must also be examined to distinguish these cells from other immune cells.

Enhancement of CD147 on M1 macrophages induces differentiation of Th17 cells in the lung interstitial fibrosis.

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Geng, Jie-jie; Zhang, Kui; Chen, Li-na; Miao, Jin-lin; Yao, Meng; Ren, Ying; Fu, Zhi-guang; Chen, Zhi-nan; Zhu, Ping

2014-09-01

Lung interstitial fibrosis is a chronic lung disease, and few effective therapies are available to halt or reverse the progression of the disease. In murine and human lung fibrosis, the expression of CD147 is increased. However, the role of CD147 in lung fibrosis has not been identified, and it remains to be determined whether lung fibrosis would be improved by decreasing the expression of CD147. A murine bleomycin-induced lung interstitial fibrosis model was used in the experiments, and HAb18 mAbs and CsA were administered during the induction of lung fibrosis. In our study, we found that the HAb18 mAbs markedly reduced the collagen score and down-regulated M1 macrophages and Th17 cells. In vitro, flow cytometry analysis showed that M1 macrophages induced higher Th17 differentiation than M2 macrophages. After treatment with HAb18 mAbs or after reducing the expression of CD147 by lentivirus interference in M1 macrophages, the level of Th17 cells were significantly inhibited. In conclusion, HAb18 mAbs or CsA treatment ameliorates lung interstitial fibrosis. CD147 promoted M1 macrophage and induced the differentiation of Th17 cells in lung interstitial fibrosis, perhaps by regulating some cytokines such as IL-6, IL-1β, IL-12 and IL-23. These results indicated that CD147 may play an important role in the development of lung interstitial fibrosis. Copyright © 2014 Elsevier B.V. All rights reserved.

Responses of murine and human macrophages to leptospiral infection: a study using comparative array analysis.

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Feng Xue

Full Text Available Leptospirosis is a re-emerging tropical infectious disease caused by pathogenic Leptospira spp. The different host innate immune responses are partially related to the different severities of leptospirosis. In this study, we employed transcriptomics and cytokine arrays to comparatively calculate the responses of murine peritoneal macrophages (MPMs and human peripheral blood monocytes (HBMs to leptospiral infection. We uncovered a series of different expression profiles of these two immune cells. The percentages of regulated genes in several biological processes of MPMs, such as antigen processing and presentation, membrane potential regulation, and the innate immune response, etc., were much greater than those of HBMs (>2-fold. In MPMs and HBMs, the caspase-8 and Fas-associated protein with death domain (FADD-like apoptosis regulator genes were significantly up-regulated, which supported previous results that the caspase-8 and caspase-3 pathways play an important role in macrophage apoptosis during leptospiral infection. In addition, the key component of the complement pathway, C3, was only up-regulated in MPMs. Furthermore, several cytokines, e.g. interleukin 10 (IL-10 and tumor necrosis factor alpha (TNF-alpha, were differentially expressed at both mRNA and protein levels in MPMs and HBMs. Some of the differential expressions were proved to be pathogenic Leptospira-specific regulations at mRNA level or protein level. Though it is still unclear why some animals are resistant and others are susceptible to leptospiral infection, this comparative study based on transcriptomics and cytokine arrays partially uncovered the differences of murine resistance and human susceptibility to leptospirosis. Taken together, these findings will facilitate further molecular studies on the innate immune response to leptospiral infection.

Responses of Murine and Human Macrophages to Leptospiral Infection: A Study Using Comparative Array Analysis

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Yang, Yingchao; Zhao, Jinping; Yang, Yutao; Cao, Yongguo; Hong, Cailing; Liu, Yuan; Sun, Lan; Huang, Minjun; Gu, Junchao

2013-01-01

Leptospirosis is a re-emerging tropical infectious disease caused by pathogenic Leptospira spp. The different host innate immune responses are partially related to the different severities of leptospirosis. In this study, we employed transcriptomics and cytokine arrays to comparatively calculate the responses of murine peritoneal macrophages (MPMs) and human peripheral blood monocytes (HBMs) to leptospiral infection. We uncovered a series of different expression profiles of these two immune cells. The percentages of regulated genes in several biological processes of MPMs, such as antigen processing and presentation, membrane potential regulation, and the innate immune response, etc., were much greater than those of HBMs (>2-fold). In MPMs and HBMs, the caspase-8 and Fas-associated protein with death domain (FADD)-like apoptosis regulator genes were significantly up-regulated, which supported previous results that the caspase-8 and caspase-3 pathways play an important role in macrophage apoptosis during leptospiral infection. In addition, the key component of the complement pathway, C3, was only up-regulated in MPMs. Furthermore, several cytokines, e.g. interleukin 10 (IL-10) and tumor necrosis factor alpha (TNF-alpha), were differentially expressed at both mRNA and protein levels in MPMs and HBMs. Some of the differential expressions were proved to be pathogenic Leptospira-specific regulations at mRNA level or protein level. Though it is still unclear why some animals are resistant and others are susceptible to leptospiral infection, this comparative study based on transcriptomics and cytokine arrays partially uncovered the differences of murine resistance and human susceptibility to leptospirosis. Taken together, these findings will facilitate further molecular studies on the innate immune response to leptospiral infection. PMID:24130911

Dexamethasone palmitate ameliorates macrophages-rich graft-versus-host disease by inhibiting macrophage functions.

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Nishiwaki, Satoshi; Nakayama, Takayuki; Murata, Makoto; Nishida, Tetsuya; Terakura, Seitaro; Saito, Shigeki; Kato, Tomonori; Mizuno, Hiroki; Imahashi, Nobuhiko; Seto, Aika; Ozawa, Yukiyasu; Miyamura, Koichi; Ito, Masafumi; Takeshita, Kyosuke; Kato, Hidefumi; Toyokuni, Shinya; Nagao, Keisuke; Ueda, Ryuzo; Naoe, Tomoki

2014-01-01

Macrophage infiltration of skin GVHD lesions correlates directly with disease severity, but the mechanisms underlying this relationship remain unclear and GVHD with many macrophages is a therapeutic challenge. Here, we characterize the macrophages involved in GVHD and report that dexamethasone palmitate (DP), a liposteroid, can ameliorate such GVHD by inhibiting macrophage functions. We found that host-derived macrophages could exacerbate GVHD in a mouse model through expression of higher levels of pro-inflammatory TNF-α and IFN-γ, and lower levels of anti-inflammatory IL-10 than resident macrophages in mice without GVHD. DP significantly decreased the viability and migration capacity of primary mouse macrophages compared to conventional dexamethasone in vitro. DP treatment on day 7 and day 14 decreased macrophage number, and attenuated GVHD score and subsequent mortality in a murine model. This is the first study to provide evidence that therapy for GVHD should be changed on the basis of infiltrating cell type.

GPBAR1/TGR5 mediates bile acid-induced cytokine expression in murine Kupffer cells.

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Guiyu Lou

Full Text Available GPBAR1/TGR5 is a novel plasma membrane-bound G protein-coupled bile acid (BA receptor. BAs are known to induce the expression of inflammatory cytokines in the liver with unknown mechanism. Here we show that without other external stimuli, TGR5 activation alone induced the expression of interleukin 1β (IL-1β and tumor necrosis factor-α (TNF-α in murine macrophage cell line RAW264.7 or murine Kupffer cells. The TGR5-mediated increase of pro-inflammatory cytokine expression was suppressed by JNK inhibition. Moreover, the induced pro-inflammatory cytokine expression in mouse liver by 1% cholic acid (CA diet was blunted in JNK-/- mice. TGR5 activation by its ligands enhanced the phosphorylation levels, DNA-binding and trans-activities of c-Jun and ATF2 transcription factors. Finally, the induced pro-inflammatory cytokine expression in Kupffer cells by TGR5 activation correlated with the suppression of Cholesterol 7α-hydroxylase (Cyp7a1 expression in murine hepatocytes. These results suggest that TGR5 mediates the BA-induced pro-inflammatory cytokine production in murine Kupffer cells through JNK-dependent pathway. This novel role of TGR5 may correlate to the suppression of Cyp7a1 expression in hepatocytes and contribute to the delicate BA feedback regulation.

Biotin deficiency up-regulates TNF-alpha production in murine macrophages.

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Kuroishi, Toshinobu; Endo, Yasuo; Muramoto, Koji; Sugawara, Shunji

2008-04-01

Biotin, a water-soluble vitamin of the B complex, functions as a cofactor of carboxylases that catalyze an indispensable cellular metabolism. Although significant decreases in serum biotin levels have been reported in patients with chronic inflammatory diseases, the biological roles of biotin in inflammatory responses are unclear. In this study, we investigated the effects of biotin deficiency on TNF-alpha production. Mice were fed a basal diet or a biotin-deficient diet for 8 weeks. Serum biotin levels were significantly lower in biotin-deficient mice than biotin-sufficient mice. After i.v. administration of LPS, serum TNF-alpha levels were significantly higher in biotin-deficient mice than biotin-sufficient mice. A murine macrophage-like cell line, J774.1, was cultured in a biotin-sufficient or -deficient medium for 4 weeks. Cell proliferation and biotinylation of intracellular proteins were decreased significantly in biotin-deficient cells compared with biotin-sufficient cells. Significantly higher production and mRNA expression of TNF-alpha were detected in biotin-deficient J774.1 cells than biotin-sufficient cells in response to LPS and even without LPS stimulation. Intracellular TNF-alpha expression was inhibited by actinomycin D, indicating that biotin deficiency up-regulates TNF-alpha production at the transcriptional level. However, the expression levels of TNF receptors, CD14, and TLR4/myeloid differentiation protein 2 complex were similar between biotin-sufficient and -deficient cells. No differences were detected in the activities of the NF-kappaB family or AP-1. The TNF-alpha induction by biotin deficiency was down-regulated by biotin supplementation in vitro and in vivo. These results indicate that biotin deficiency may up-regulate TNF-alpha production or that biotin excess down-regulates TNF-alpha production, suggesting that biotin status may influence inflammatory diseases.

Construction of genetic markers for the study of Salmonella typhimurium infection of murine macrophages

DEFF Research Database (Denmark)

Jelsbak, Lotte; Olsen, John Elmerdahl

in combination with available host markers it will be possible to estimate the time-point at which a specific gene is required for progression of SCV maturation. These developmentally regulated reporter fusions constitute a set of novel developmental markers for the study of Salmonella Typhimurium infection...... with the host cell, (2) Formation of early SCV, (3) Maturation into late SCV, (4) Initiation of bacterial replication, (5) Formation of Sifs. In this project, we have constructed a set of reporter fusions which are temporally and spatially regulated during the progression of SCV maturation. The reporter fusions...... were constructed using Red-mediated recombination (1) and the promoters were selected from the recently published expressional data of Salmonella infection of murine macrophages (2). As reporter proteins we both use a stable GFPmut3 variant as well as an unstable GFP variant (3). Using these fusions...

Signal-transducing mechanisms of ketamine-caused inhibition of interleukin-1β gene expression in lipopolysaccharide-stimulated murine macrophage-like Raw 264.7 cells

International Nuclear Information System (INIS)

Chen, T.-L.; Chang, C.-C.; Lin, Y.-L.; Ueng, Y.-F.; Chen, R.-M.

2009-01-01

Ketamine may affect the host immunity. Interleukin-1β (IL-1β), IL-6, and tumor necrosis factor-α (TNF-α) are pivotal cytokines produced by macrophages. This study aimed to evaluate the effects of ketamine on the regulation of inflammatory cytokine gene expression, especially IL-1β, in lipopolysaccharide (LPS)-activated murine macrophage-like Raw 264.7 cells and its possible signal-transducing mechanisms. Administration of Raw 264.7 cells with a therapeutic concentration of ketamine (100 μM), LPS, or a combination of ketamine and LPS for 1, 6, and 24 h was not cytotoxic to macrophages. Exposure to 100 μM ketamine decreased the binding affinity of LPS and LPS-binding protein but did not affect LPS-induced RNA and protein synthesis of TLR4. Treatment with LPS significantly increased IL-1β, IL-6, and TNF-α gene expressions in Raw 264.7 cells. Ketamine at a clinically relevant concentration did not affect the synthesis of these inflammatory cytokines, but significantly decreased LPS-caused increases in these cytokines. Immunoblot analyses, an electrophoretic mobility shift assay, and a reporter luciferase activity assay revealed that ketamine significantly decreased LPS-induced translocation and DNA binding activity of nuclear factor-kappa B (NFκB). Administration of LPS sequentially increased the phosphorylations of Ras, Raf, MEK1/2, ERK1/2, and IKK. However, a therapeutic concentration of ketamine alleviated such augmentations. Application of toll-like receptor 4 (TLR4) small interfering (si)RNA reduced cellular TLR4 amounts and ameliorated LPS-induced RAS activation and IL-1β synthesis. Co-treatment with ketamine and TLR4 siRNA synergistically ameliorated LPS-caused enhancement of IL-1β production. Results of this study show that a therapeutic concentration of ketamine can inhibit gene expression of IL-1β possibly through suppressing TLR4-mediated signal-transducing phosphorylations of Ras, Raf, MEK1/2, ERK1/2, and IKK and subsequent translocation and

Effects of protein-energy malnutrition on NF-kappaB signalling in murine peritoneal macrophages.

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Fock, Ricardo Ambrósio; Rogero, Marcelo Macedo; Vinolo, Marco Aurélio Ramirez; Curi, Rui; Borges, Maria Carolina; Borelli, Primavera

2010-04-01

Protein-energy malnutrition (PEM) is an important public health problem affecting millions of people worldwide. PEM decreases resistance to infection, impairing a number of physiological processes. In unstimulated cells, NF-kappaB is kept from binding to its consensus sequence by the inhibitor I kappaB alpha, which retains NF-kappaB in the cytoplasm. Upon various signals, such as lipopolysaccharide (LPS), I kappaB alpha is rapidly degraded and NF-kappaB is induced to translocate into the nucleus, where it activates expression of various genes that participate in the inflammatory response, including those involved in the synthesis of TNF-alpha. TRAF-6 is a cytoplasmic adapter protein that links the stimulatory signal from Toll like receptor-4 to NF-kappaB. The aim of this study was to evaluate the effect of malnutrition on induction of TNF-alpha by LPS in murine peritoneal macrophages. We evaluated peritoneal cellularity, the expression of MyD88, TRAF-6, IKK, I kappaB alpha and NF-kappaB, NF-kappaB activation and TNF-alpha mRNA and protein synthesis in macrophages. Two-month-old male BALB/C mice were submitted to PEM with a low-protein diet that contained 2% protein, compared to 12% protein in the control diet. When the experimental group had lost about 20% of the original body weight, it was used in the subsequent experiments. Malnourished animals presented anemia, leucopenia and severe reduction in peritoneal cavity cellularity. TNF-alpha mRNA and protein levels of macrophages stimulated with LPS were significantly lower in malnourished animals. PEM also decreased TRAF-6 expression and NF-kappaB activation after LPS stimulation. These results led us to conclude that PEM changes NF-kB signalling pathway in macrophages to LPS stimulus.

Modulation of cell adhesion and viability of cultured murine bone marrow cells by arsenobetaine, a major organic arsenic compound in marine animals.

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Sakurai, T; Fujiwara, K

2001-01-01

1. In this study, we investigated the biological effects of trimethyl (carboxymethyl) arsonium zwitterion, namely arsenobetaine (AsBe), which is a major organic arsenic compound in marine animals using murine bone marrow (BM) cells and compared them with those of an inorganic arsenical, sodium arsenite, in vitro. 2. Sodium arsenite showed strong cytotoxicity in BM cells, and its IC(50) was 6 microM. In contrast, AsBe significantly enhanced the viability of BM cells in a dose-dependent manner during a 72-h incubation; about a twofold increase in the viability of cells compared with that of control cells cultured with the medium alone was observed with a microM level of AsBe. 3. In morphological investigations, AsBe enhanced the numbers of large mature adherent cells, especially granulocytes, during a 72-h BM culture. When BM cells were cultured together with AsBe and a low dose (1 u ml(-1)) of recombinant murine granulocyte/macrophage colony-stimulating factor (rMu GM-CSF), significant additive-like increasing effects were observed on the numbers of both granulocytes and macrophages originated from BM cells. However, AsBe did not cause proliferation of BM cells at all as determined by colony-forming assay using a gelatinous medium. 4. These findings demonstrate the unique and potent biological effects in mammalian cells of AsBe, a major organic arsenic compound in various marine animals which are ingested daily as seafood in many countries.

Ecotropic murine leukemia virus-induced fusion of murine cells

International Nuclear Information System (INIS)

Pinter, A.; Chen, T.; Lowy, A.; Cortez, N.G.; Silagi, S.

1986-01-01

Extensive fusion occurs upon cocultivation of murine fibroblasts producing ecotropic murine leukemia viruses (MuLVs) with a large variety of murine cell lines in the presence of the polyene antibiotic amphotericin B, the active component of the antifungal agent Fungizone. The resulting polykaryocytes contain nuclei from both infected and uninfected cells, as evidenced by autoradiographic labeling experiments in which one or the other parent cell type was separately labeled with [ 3 H]thymidine and fused with an unlabeled parent. This cell fusion specifically requires the presence of an ecotropic MuLV-producing parent and is not observed for cells producing xenotropic, amphotropic, or dualtropic viruses. Mouse cells infected with nonecotropic viruses retain their sensitivity toward fusion, whereas infection with ecotropic viruses abrogates the fusion of these cells upon cocultivation with other ecotropic MuLV-producing cells. Nonmurine cells lacking the ecotropic gp70 receptor are not fused under similar conditions. Fusion is effectively inhibited by monospecific antisera to gp70, but not by antisera to p15(E), and studies with monoclonal antibodies identify distinct amino- and carboxy-terminal gp70 regions which play a role in the fusion reaction. The enhanced fusion which occurs in the presence of amphotericin B provides a rapid and sensitive assay for the expression of ecotropic MuLVs and should facilitate further mechanistic studies of MuLV-induced fusion of murine cells

HIV-1 Myristoylated Nef Treatment of Murine Microglial Cells Activates Inducible Nitric Oxide Synthase, NO2 Production and Neurotoxic Activity.

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Giorgio Mangino

Full Text Available The potential role of the human immunodeficiency virus-1 (HIV-1 accessory protein Nef in the pathogenesis of neuroAIDS is still poorly understood. Nef is a molecular adapter that influences several cellular signal transduction events and membrane trafficking. In human macrophages, Nef expression induces the production of extracellular factors (e.g. pro-inflammatory chemokines and cytokines and the recruitment of T cells, thus favoring their infection and its own transfer to uninfected cells via exosomes, cellular protrusions or cell-to-cell contacts. Murine cells are normally not permissive for HIV-1 but, in transgenic mice, Nef is a major disease determinant. Both in human and murine macrophages, myristoylated Nef (myr+Nef treatment has been shown to activate NF-κB, MAP kinases and interferon responsive factor 3 (IRF-3, thereby inducing tyrosine phosphorylation of signal transducers and activator of transcription (STAT-1, STAT-2 and STAT-3 through the production of proinflammatory factors.We report that treatment of BV-2 murine microglial cells with myr+Nef leads to STAT-1, -2 and -3 tyrosine phosphorylation and upregulates the expression of inducible nitric oxide synthase (iNOS with production of nitric oxide. We provide evidence that extracellular Nef regulates iNOS expression through NF-κB activation and, at least in part, interferon-β (IFNβ release that acts in concert with Nef. All of these effects require both myristoylation and a highly conserved acidic cluster in the viral protein. Finally, we report that Nef induces the release of neurotoxic factors in the supernatants of microglial cells.These results suggest a potential role of extracellular Nef in promoting neuronal injury in the murine model. They also indicate a possible interplay between Nef and host factors in the pathogenesis of neuroAIDS through the production of reactive nitrogen species in microglial cells.

EcoHIV infection of mice establishes latent viral reservoirs in T cells and active viral reservoirs in macrophages that are sufficient for induction of neurocognitive impairment.

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Gu, Chao-Jiang; Borjabad, Alejandra; Hadas, Eran; Kelschenbach, Jennifer; Kim, Boe-Hyun; Chao, Wei; Arancio, Ottavio; Suh, Jin; Polsky, Bruce; McMillan, JoEllyn; Edagwa, Benson; Gendelman, Howard E; Potash, Mary Jane; Volsky, David J

2018-06-01

Suppression of HIV replication by antiretroviral therapy (ART) or host immunity can prevent AIDS but not other HIV-associated conditions including neurocognitive impairment (HIV-NCI). Pathogenesis in HIV-suppressed individuals has been attributed to reservoirs of latent-inducible virus in resting CD4+ T cells. Macrophages are persistently infected with HIV but their role as HIV reservoirs in vivo has not been fully explored. Here we show that infection of conventional mice with chimeric HIV, EcoHIV, reproduces physiological conditions for development of disease in people on ART including immunocompetence, stable suppression of HIV replication, persistence of integrated, replication-competent HIV in T cells and macrophages, and manifestation of learning and memory deficits in behavioral tests, termed here murine HIV-NCI. EcoHIV established latent reservoirs in CD4+ T lymphocytes in chronically-infected mice but could be induced by epigenetic modulators ex vivo and in mice. In contrast, macrophages expressed EcoHIV constitutively in mice for up to 16 months; murine leukemia virus (MLV), the donor of gp80 envelope in EcoHIV, did not infect macrophages. Both EcoHIV and MLV were found in brain tissue of infected mice but only EcoHIV induced NCI. Murine HIV-NCI was prevented by antiretroviral prophylaxis but once established neither persistent EcoHIV infection in mice nor NCI could be reversed by long-acting antiretroviral therapy. EcoHIV-infected, athymic mice were more permissive to virus replication in macrophages than were wild-type mice, suffered cognitive dysfunction, as well as increased numbers of monocytes and macrophages infiltrating the brain. Our results suggest an important role of HIV expressing macrophages in HIV neuropathogenesis in hosts with suppressed HIV replication.

Cyanotoxins at low doses induce apoptosis and inflammatory effects in murine brain cells: Potential implications for neurodegenerative diseases

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Takser, Larissa; Benachour, Nora; Husk, Barry; Cabana, Hubert; Gris, Denis

2016-01-01

Cyanotoxins have been shown to be highly toxic for mammalian cells, including brain cells. However, little is known about their effect on inflammatory pathways. This study investigated whether mammalian brain and immune cells can be a target of certain cyanotoxins, at doses approximating those in the guideline levels for drinking water, either alone or in mixtures. We examined the effects on cellular viability, apoptosis and inflammation signalling of several toxins on murine macrophage-like ...

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

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

2015-08-01

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

IL-10 down-regulates the expression of survival associated gene hspX of Mycobacterium tuberculosis in murine macrophage

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Babban Jee

2017-07-01

Full Text Available Mycobacterium tuberculosis (MTB adopts a special survival strategy to overcome the killing mechanism(s of host immune system. Amongst the many known factors, small heat shock protein 16.3 (sHSP16.3 of MTB encoded by gene hspX has been reported to be critical for the survival of MTB. In the present study, the effect of recombinant murine interferon-gamma (rmIFN-γ and recombinant murine interleukin-10 (rmIL-10 on the expression of gene hspX of MTB in murine macrophage RAW264.7 has been investigated. By real-time RT-PCR, it was observed that three increasing concentrations (5, 25 and 50 ng/ml of rmIFN-γ significantly up-regulated the expression of hspX whereas similar concentrations of rmIL-10 (5, 25 and 50 ng/ml significantly down-regulated the hspX expression. This effect was not only dependent on the concentration of the stimulus but this was time-dependent as well. A contrasting pattern of hspX expression was observed against combinations of two different concentrations of rmIFN-γ and rmIL-10. The study results suggest that rIL-10 mediated down-regulation of hspX expression, in the presence of low concentration of rIFN-γ, could be used as an important strategy to decrease the dormancy of MTB in its host and thus making MTB susceptible to the standard anti-mycobacterial therapy used for treating tuberculosis. However, as these are only preliminary results in the murine cell line model, this hypothesis needs to be first validated in human cell lines and subsequently in animal models mimicking the latent infection using clinical isolates of MTB before considering the development of modified regimens for humans.

Corticotropin-Releasing Hormone (CRH Promotes Macrophage Foam Cell Formation via Reduced Expression of ATP Binding Cassette Transporter-1 (ABCA1.

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Wonkyoung Cho

Full Text Available Atherosclerosis, the major pathology of cardiovascular disease, is caused by multiple factors involving psychological stress. Corticotropin-releasing hormone (CRH, which is released by neurosecretory cells in the hypothalamus, peripheral nerve terminals and epithelial cells, regulates various stress-related responses. Our current study aimed to verify the role of CRH in macrophage foam cell formation, the initial critical stage of atherosclerosis. Our quantitative real-time reverse transcriptase PCR (qRT-PCR, semi-quantitative reverse transcriptase PCR, and Western blot results indicate that CRH down-regulates ATP-binding cassette transporter-1 (ABCA1 and liver X receptor (LXR-α, a transcription factor for ABCA1, in murine peritoneal macrophages and human monocyte-derived macrophages. Oil-red O (ORO staining and intracellular cholesterol measurement of macrophages treated with or without oxidized LDL (oxLDL and with or without CRH (10 nM in the presence of apolipoprotein A1 (apoA1 revealed that CRH treatment promotes macrophage foam cell formation. The boron-dipyrromethene (BODIPY-conjugated cholesterol efflux assay showed that CRH treatment reduces macrophage cholesterol efflux. Western blot analysis showed that CRH-induced down-regulation of ABCA1 is dependent on phosphorylation of Akt (Ser473 induced by interaction between CRH and CRH receptor 1(CRHR1. We conclude that activation of this pathway by CRH accelerates macrophage foam cell formation and may promote stress-related atherosclerosis.

Effect of nitric oxide-releasing derivative of indomethacin on Prevotella intermedia lipopolysaccharide-induced production of proinflammatory mediators in murine macrophages.

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Choe, So-Hui; Choi, Eun-Young; Hyeon, Jin-Yi; Choi, In Soon; Kim, Sung-Jo

2017-10-14

The purpose of this study was to investigate the influences of NCX 2121, a nitric oxide (NO)-releasing derivative of indomethacin, upon the generation of proinflammatory mediators using murine macrophages activated by lipopolysaccharide (LPS) isolated from Prevotella intermedia, which is one of the pathogens implicated in periodontal diseases. Inducible NO synthase (iNOS)-derived NO, IL-1β and IL-6 as well as their relevant mRNA were significantly attenuated by NCX 2121 in RAW264.7 cells activated by P. intermedia LPS. NCX 2121 was much more effective than the parental compound indomethacin in reducing these proinflammatory mediators. NCX 2121 triggered induction of heme oxygenase-1 (HO-1) in cells exposed to P. intermedia LPS, and its inhibitory influence upon P. intermedia LPS-elicited NO generation was notably blocked by SnPP treatment. NCX 2121 attenuated NF-κB-dependent SEAP release induced by P. intermedia LPS. NCX 2121 did not display inhibitory action towards IκB-α degradation triggered by LPS. Instead, it significantly diminished nuclear translocation as well as DNA-binding action of NF-κB p50 subunit elicited by P. intermedia LPS. Further, NCX 2121 significantly up-regulated SOCS1 mRNA expression in cells challenged with P. intermedia LPS. In summary, NCX 2121 down-regulates P. intermedia LPS-elicited generation of NO, IL-1β and IL-6 in murine macrophages in a mechanism that involves anti-inflammatory HO-1 induction as well as decrement of NF-κB activation, which may be associated with SOCS1 expression. NCX 2121 may have potential benefits as a host immunomodulatory agent for the therapy of periodontal disease. Copyright © 2017 Elsevier Inc. All rights reserved.

NCX 4040, a nitric oxide-donating aspirin derivative, inhibits Prevotella intermedia lipopolysaccharide-induced production of proinflammatory mediators in murine macrophages.

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Choi, Eun-Young; Choe, So-Hui; Hyeon, Jin-Yi; Park, Hae Ryoun; Choi, Jeom-Il; Choi, In Soon; Kim, Sung-Jo

2015-12-05

In this study, the effects and underlying mechanisms of NCX 4040, a nitric oxide (NO)-donating aspirin derivative, on the production of proinflammatory mediators were examined using murine macrophages exposed to lipopolysaccharide (LPS) from Prevotella intermedia, a pathogen implicated in the etiology of periodontal disease. NCX 4040 significantly reduced P. intermedia LPS-induced production of inducible NO synthase (iNOS)-derived NO, IL-1β and IL-6 as well as their mRNA expression in RAW264.7 cells. Notably, NCX 4040 was much more effective than the parental compound aspirin in reducing LPS-induced production of inflammatory mediators. NCX 4040 induced the expression of heme oxygenase-1 (HO-1) in cells treated with P. intermedia LPS, and the suppressive effect of NCX 4040 on LPS-induced NO production was significantly reversed by SnPP, a competitive HO-1 inhibitor. NCX 4040 did not influence LPS-induced phosphorylation of JNK and p38. IκB-α degradation as well as nuclear translocation and DNA-binding activities of NF-κB p65 and p50 subunits induced by P. intermedia LPS were significantly reduced by NCX 4040. Besides, LPS-induced phosphorylation of STAT1 and STAT3 was significantly down-regulated by NCX 4040. Further, NCX 4040 elevated the SOCS1 mRNA in cells stimulated with LPS. This study indicates that NCX 4040 inhibits P. intermedia LPS-induced production of NO, IL-1β and IL-6 in murine macrophages through anti-inflammatory HO-1 induction and suppression of NF-κB, STAT1 and STAT3 activation, which is associated with the activation of SOCS1 signaling. NCX 4040 could potentially be a promising tool in the treatment of periodontal disease, although further studies are required to verify this. Copyright © 2015 Elsevier B.V. All rights reserved.

Activation of nucleotide-binding domain-like receptor containing protein 3 inflammasome in dendritic cells and macrophages by Streptococcus sanguinis.

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Saeki, Ayumi; Suzuki, Toshihiko; Hasebe, Akira; Kamezaki, Ryousuke; Fujita, Mari; Nakazawa, Futoshi; Shibata, Ken-Ichiro

2017-03-01

Streptococcus sanguinis is frequently isolated from the blood of patients with infective endocarditis and contributes to the pathology of this disease through induction of interleukin (IL)-1β responsible for the development of the disease. However, the mechanism of IL-1β induction remains unknown. In this study, S. sanguinis activated a murine dendritic cell (DC) to induce IL-1β and this activity was attenuated by silencing the mRNAs of nucleotide-binding domain-like receptor containing protein 3 (NLRP3) and caspase-1. S. sanguinis induced IL-1β production in murine bone marrow-derived macrophage, but this activity was significantly reduced in bone marrow-derived macrophages from NLRP3-, apoptosis-associated speck-like protein containing a caspase-recruitment domain-, and caspase-1-deficient mice. DC phagocytosed S. sanguinis cells, followed by the release of adenosine triphosphate (ATP). The ATP-degradating enzyme attenuated the release of ATP and IL-1β. The inhibitors for ATP receptor reduced IL-1β release in DC. These results strongly suggest that S. sanguinis has the activity to induce IL-1β through the NLRP3 inflammasome in macrophage and DC and interaction of purinergic receptors with ATP released is involved in expression of the activity. © 2016 John Wiley & Sons Ltd.

Colony-stimulating factor (CSF) radioimmunoassay: detection of a CSF subclass stimulating macrophage production

International Nuclear Information System (INIS)

Stanley, E.R.

1979-01-01

Colony-stimulating factors (CSFs) stimulate the differentiation of immature precursor cells to mature granulocytes and macrophages. Purified 125 I-labeled murine L cell CSF has been used to develop a radioimmunoassay (RIA) that detects a subclass of CSFs that stimulates macrophage production. Murine CSF preparations that contain this subclass of CSF compete for all of the CSF binding sites on anti-L cell CSF antibody. With the exception of mouse serum, which can contain inhibitors of the bioassay, there is complete correspondence between activities determined by RIA and those determined by bioassay. The RIA is slightly more sensitive than the bioassay, detecting approximately 0.3 fmol of purified L cell CSF. It can also detect this subclass of CSF in chickens, rats, and humans. In the mouse, the subclass is distinguished from other CSFs by a murine cell bioassay dose-response curve in which 90% of the response occurs over a 10-fold (rather than a 100-fold) increase in concentration, by stimulating the formations of colonies contaning a high proportion of mononuclear (rather than granulocytic) cells, and by certain physical characteristics

Macrophage Interaction with Paracoccidioides brasiliensis Yeast Cells Modulates Fungal Metabolism and Generates a Response to Oxidative Stress.

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Juliana Alves Parente-Rocha

Full Text Available Macrophages are key players during Paracoccidioides brasiliensis infection. However, the relative contribution of the fungal response to counteracting macrophage activity remains poorly understood. In this work, we evaluated the P. brasiliensis proteomic response to macrophage internalization. A total of 308 differentially expressed proteins were detected in P. brasiliensis during infection. The positively regulated proteins included those involved in alternative carbon metabolism, such as enzymes involved in gluconeogenesis, beta-oxidation of fatty acids and amino acids catabolism. The down-regulated proteins during P. brasiliensis internalization in macrophages included those related to glycolysis and protein synthesis. Proteins involved in the oxidative stress response in P. brasiliensis yeast cells were also up-regulated during macrophage infection, including superoxide dismutases (SOD, thioredoxins (THX and cytochrome c peroxidase (CCP. Antisense knockdown mutants evaluated the importance of CCP during macrophage infection. The results suggested that CCP is involved in a complex system of protection against oxidative stress and that gene silencing of this component of the antioxidant system diminished the survival of P. brasiliensis in macrophages and in a murine model of infection.

Oral administration of kefiran induces changes in the balance of immune cells in a murine model.

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Medrano, Micaela; Racedo, Silvia M; Rolny, Ivanna S; Abraham, Analía G; Pérez, Pablo F

2011-05-25

The aim of the present study was to evaluate the effect of the oral administration of kefiran on the balance of immune cells in a murine model. Six week old BALB/c mice were treated with kefiran (300 mg/L) for 0, 2 and 7 days. Kefiran treatment increased the number of IgA+ cells in lamina propria after 2 and 7 days. Percentage of B220+/MHCII(high) cells in mesenteric lymph nodes (2 days) and Peyer's patches (7 days) was higher compared to untreated control mice. An increase of macrophages (F4/80+ cells) was observed in lamina propria and peritoneal cavity (2 and 7 days). In contrast, at day 7, macrophage population decreased in Peyer's patches. These results show the ability of kefiran to modify the balance of immune cells in intestinal mucosa. This property could be highly relevant for the comprehension of the probiotic effect attributed to kefir.

PEGylation controls attachment and engulfment of monodisperse magnetic poly(2-hydroxyethyl methacrylate) microspheres by murine J774.2 macrophages

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Horák, Daniel; Hlidková, Helena; Klyuchivska, Olga; Grytsyna, Iryna; Stoika, Rostyslav

2017-12-01

The first objective of this work was to prepare biocompatible magnetic polymer microspheres with reactive functional groups that could withstand nonspecific protein adsorption from biological media. Carboxyl group-containing magnetic poly(2-hydroxyethyl methacrylate) (mgt.PHEMA) microspheres ∼4 μm in size were prepared by multistage swelling polymerization, precipitation of iron oxide inside their pores, and coating with an α-methoxy-ω-amino poly(ethylene glycol) (CH3O-PEG750-NH2 or CH3O-PEG5,000-NH2)/α-amino-ω-t-Boc-amino poly(ethylene glycol) (H2N-PEG5,000-NH-t-Boc) mixture. The mgt.PHEMA@PEG microspheres contained ∼10 μmol COOH per g. Biocompatibility of the particles was evaluated by their treatment with human embryonic kidney cells of the HEK293 line. The microspheres did not interfere with the growth of these cells, suggesting that the particles can be considered non-toxic. A second goal of this study was to address on the interaction of the developed microspheres with macrophages that commonly eliminate foreign microbodies appearing in organisms. Murine J774.2 macrophages (J774.2) were cultured in the presence of the neat and PEGylated microspheres for 2 h. Mgt.PHEMA@PEG5,000 microspheres significantly adhered to the surface of J774.2 macrophages but were minimally engulfed. Due to these properties, the mgt.PHEMA@PEG microspheres might be useful for application in drug delivery systems and monitoring of the efficiency of phagocytosis.

Involvement of Nitric Oxide on Bothropoides insularis Venom Biological Effects on Murine Macrophages In Vitro.

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Ramon R P P B de Menezes

Full Text Available Viperidae venom has several local and systemic effects, such as pain, edema, inflammation, kidney failure and coagulopathy. Additionally, bothropic venom and its isolated components directly interfere on cellular metabolism, causing alterations such as cell death and proliferation. Inflammatory cells are particularly involved in pathological envenomation mechanisms due to their capacity of releasing many mediators, such as nitric oxide (NO. NO has many effects on cell viability and it is associated to the development of inflammation and tissue damage caused by Bothrops and Bothropoides venom. Bothropoides insularis is a snake found only in Queimada Grande Island, which has markedly toxic venom. Thus, the aim of this work was to evaluate the biological effects of Bothropoides insularis venom (BiV on RAW 264.7 cells and assess NO involvement. The venom was submitted to colorimetric assays to identify the presence of some enzymatic components. We observed that BiV induced H2O2 production and showed proteolytic and phospholipasic activities. RAW 264.7 murine macrophages were incubated with different concentrations of BiV and then cell viability was assessed by MTT reduction assay after 2, 6, 12 and 24 hours of incubation. A time- and concentration-dependent effect was observed, with a tendency to cell proliferation at lower BiV concentrations and cell death at higher concentrations. The cytotoxic effect was confirmed after lactate dehydrogenase (LDH measurement in the supernatant from the experimental groups. Flow cytometry analyses revealed that necrosis is the main cell death pathway caused by BiV. Also, BiV induced NO release. The inhibition of both proliferative and cytotoxic effects with L-NAME were demonstrated, indicating that NO is important for these effects. Finally, BiV induced an increase in iNOS expression. Altogether, these results demonstrate that B. insularis venom have proliferative and cytotoxic effects on macrophages, with

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.

Corn silk induces nitric oxide synthase in murine macrophages.

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Kim, Kyung A; Choi, Sang Kyu; Choi, Hye Seon

2004-12-31

Corn silk has been purified as an anticoagulant previously and the active component is a polysaccharide with a molecular mass of 135 kDa. It activates murine macrophages to induce nitric oxide synthase (NOS) and generate substantial amounts of NO in time and dose-dependent manners. It was detectable first at 15 h after stimulation by corn silk, peaked at 24 h, and undetectable by 48 h. Induction of NOS is inhibited by pyrolidine dithiocarbamate (PDTC) and genistein, an inhibitor of nuclear factor kappa B (NF-kappaB) and tyrosine kinase, respectively, indicating that iNOS stimulated by corn silk is associated with tyrosine kinase and NF-kappaB signaling pathways. IkappaB-alpha degradation was detectible at 10 min, and the level was restored at 120 min after treatment of corn silk. Corn silk induced nuclear translocation of NF-kappaB by phosphorylation and degradation of IkappaB-alpha.

Impaired Hematopoiesis and Disrupted Monocyte/Macrophage Homeostasis in Mucopolysaccharidosis Type I Mice.

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Viana, Gustavo Monteiro; Buri, Marcus Vinícius; Paredes-Gamero, Edgar Julian; Martins, Ana Maria; D'Almeida, Vânia

2016-03-01

Mucopolysaccharidosis type I (MPS I) is a rare autosomal recessive disease caused by alpha-L-iduronidase deficiency in which heparan and dermatan sulfate degradation is compromised. Besides primary lysosomal glycosaminoglycan accumulation, further changes in cellular functions have also been described in several murine MPS models. Herein, we evaluated alterations in hematopoiesis and its implications on the production of mature progeny in a MPS I murine model. Despite the significant increase in hematopoietic stem cells, a reduction in common myeloid progenitors and granulocyte-macrophage progenitor cells was observed in Idua -/- mice bone marrow. Furthermore, no alterations in number, viability nor activation of cell death mechanisms were observed in Idua -/- mice mature macrophages but they presented higher sensitivity to apoptotic induction after staurosporine treatment. In addition, changes in Ca(2+) signaling and a reduction in phagocytosis ability were also found. In summary, our results revealed significant intracellular changes in mature Idua -/- macrophages related to alterations in Idua -/- mice hematopoiesis, revealing a disruption in cell homeostasis. These results provide new insights into physiopathology of MPS I. © 2015 Wiley Periodicals, Inc.

Effects of vitamin D(3)-binding protein-derived macrophage activating factor (GcMAF) on angiogenesis.

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Kanda, Shigeru; Mochizuki, Yasushi; Miyata, Yasuyoshi; Kanetake, Hiroshi; Yamamoto, Nobuto

2002-09-04

The vitamin D(3)-binding protein (Gc protein)-derived macrophage activating factor (GcMAF) activates tumoricidal macrophages against a variety of cancers indiscriminately. We investigated whether GcMAF also acts as an antiangiogenic factor on endothelial cells. The effects of GcMAF on angiogenic growth factor-induced cell proliferation, chemotaxis, and tube formation were examined in vitro by using cultured endothelial cells (murine IBE cells, porcine PAE cells, and human umbilical vein endothelial cells [HUVECs]) and in vivo by using a mouse cornea micropocket assay. Blocking monoclonal antibodies to CD36, a receptor for the antiangiogenic factor thrombospondin-1, which is also a possible receptor for GcMAF, were used to investigate the mechanism of GcMAF action. GcMAF inhibited the endothelial cell proliferation, chemotaxis, and tube formation that were all stimulated by fibroblast growth factor-2 (FGF-2), vascular endothelial growth factor-A, or angiopoietin 2. FGF-2-induced neovascularization in murine cornea was also inhibited by GcMAF. Monoclonal antibodies against murine and human CD36 receptor blocked the antiangiogenic action of GcMAF on the angiogenic factor stimulation of endothelial cell chemotaxis. In addition to its ability to activate tumoricidal macrophages, GcMAF has direct antiangiogenic effects on endothelial cells independent of tissue origin. The antiangiogenic effects of GcMAF may be mediated through the CD36 receptor.

Sonicated Protein Fractions of Mycoplasma hyopneumoniae Induce Inflammatory Responses and Differential Gene Expression in a Murine Alveolar Macrophage Cell Line.

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Damte, Dereje; Lee, Seung-Jin; Birhanu, Biruk Tesfaye; Suh, Joo-Won; Park, Seung-Chun

2015-12-28

Mycoplasma hyopneumoniae is known to cause porcine enzootic pneumonia (EP), an important disease in swine production. The objective of this study was to examine the effects of sonicated protein fractions of M. hyopneumoniae on inflammatory response and gene expression in the murine alveolar macrophage MH-S cell line. The effects of sonicated protein fractions and intact M. hyopneumoniae on the gene expression of cytokines and iNOS were assessed using RT-PCR. The Annealing Control Primer (ACP)-based PCR method was used to screen differentially expressed genes. Increased transcription of interleukin (IL)-1β, IL-6, tumor necrosis factor (TNF)-α, COX-2, and iNOS mRNA was observed after exposure to the supernatant (SPT), precipitant (PPT), and intact M. hyopneumoniae protein. A time-dependent analysis of the mRNA expression revealed an upregulation after 4 h for IL-6 and iNOS and after 12 h for IL-1β and TNF-α, for both SPT and PPT; the fold change in COX-2 expression was less. A dose- and time-dependent correlation was observed in nitrite (NO) production for both protein fractions; however, there was no significant difference between the effects of the two protein fractions. In a differential gene analysis, PCR revealed differential expression for nine gene bands after 3 h of stimulation - only one gene was downregulated, while the remaining eight were upregulated. The results of this study provide insights that help improve our understanding of the mechanisms underlying the pathogenesis of and macrophage defenses against M. hyopneumoniae assault, and suggest targets for future studies on therapeutic interventions for M. hyopneumoniae infections.

Exosome derived from epigallocatechin gallate treated breast cancer cells suppresses tumor growth by inhibiting tumor-associated macrophage infiltration and M2 polarization

International Nuclear Information System (INIS)

Jang, Ji-Young; Lee, Jong-Kuen; Jeon, Yoon-Kyung; Kim, Chul-Woo

2013-01-01

Tumor-associated macrophages (TAM) play an important role in tumor microenvironment. Particularly, M2 macrophages contribute to tumor progression, depending on the expression of NF-κB. Tumor-derived exosomes can modulate tumor microenvironment by transferring miRNAs to immune cells. Epigallocatechin gallate (EGCG) has well known anti-tumor effects; however, no data are available on the influence of EGCG on communication with cancer cells and TAM. Murine breast cancer cell lines, 4T1, was used for in vivo and ex vivo studies. Exosome was extracted from EGCG-treated 4T1 cells, and the change of miRNAs was screened using microarray. Tumor cells or TAM isolated from murine tumor graft were incubated with exosomes derived from EGCG-treated and/or miR-16 inhibitor-transfected 4T1 cells. Chemokines for monocytes (CSF-1 and CCL-2), cytokines both with high (IL-6 and TGF-β) and low (TNF-α) expression in M2 macrophages, and molecules in NF-κB pathway (IKKα and Iκ-B) were evaluated by RT-qPCR or western blot. EGCG suppressed tumor growth in murine breast cancer model, which was associated with decreased TAM and M2 macrophage infiltration. Expression of chemokine for monocytes (CSF-1 and CCL-2) were low in tumor cells from EGCG-treated mice, and cytokines of TAM was skewed from M2- into M1-like phenotype by EGCG as evidenced by decreased IL-6 and TGF-β and increased TNF-α. Ex vivo incubation of isolated tumor cells with EGCG inhibited the CSF-1 and CCL-2 expression. Ex vivo incubation of TAM with exosomes from EGCG-treated 4T1 cells led to IKKα suppression and concomitant I-κB accumulation; increase of IL-6 and TGF-β; and, decrease of TNF-α. EGCG up-regulated miR-16 in 4T1 cells and in the exosomes. Treatment of tumor cells or TAM with exosomes derived from EGCG-treated and miR-16-knock-downed 4T1 cells restored the above effects on chemokines, cytokines, and NF-κB pathway elicited by EGCG-treated exosomes. Our data demonstrate that EGCG up-regulates miR-16 in

Further characterization of a highly attenuated Yersinia pestis CO92 mutant deleted for the genes encoding Braun lipoprotein and plasminogen activator protease in murine alveolar and primary human macrophages.

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van Lier, Christina J; Tiner, Bethany L; Chauhan, Sadhana; Motin, Vladimir L; Fitts, Eric C; Huante, Matthew B; Endsley, Janice J; Ponnusamy, Duraisamy; Sha, Jian; Chopra, Ashok K

2015-03-01

We recently characterized the Δlpp Δpla double in-frame deletion mutant of Yersinia pestis CO92 molecularly, biologically, and immunologically. While Braun lipoprotein (Lpp) activates toll-like receptor-2 to initiate an inflammatory cascade, plasminogen activator (Pla) protease facilitates bacterial dissemination in the host. The Δlpp Δpla double mutant was highly attenuated in evoking bubonic and pneumonic plague, was rapidly cleared from mouse organs, and generated humoral and cell-mediated immune responses to provide subsequent protection to mice against a lethal challenge dose of wild-type (WT) CO92. Here, we further characterized the Δlpp Δpla double mutant in two murine macrophage cell lines as well as in primary human monocyte-derived macrophages to gauge its potential as a live-attenuated vaccine candidate. We first demonstrated that the Δpla single and the Δlpp Δpla double mutant were unable to survive efficiently in murine and human macrophages, unlike WT CO92. We observed that the levels of Pla and its associated protease activity were not affected in the Δlpp single mutant, and, likewise, deletion of the pla gene from WT CO92 did not alter Lpp levels. Further, our study revealed that both Lpp and Pla contributed to the intracellular survival of WT CO92 via different mechanisms. Importantly, the ability of the Δlpp Δpla double mutant to be phagocytized by macrophages, to stimulate production of tumor necrosis factor-α and interleukin-6, and to activate the nitric oxide killing pathways of the host cells remained unaltered when compared to the WT CO92-infected macrophages. Finally, macrophages infected with either the WT CO92 or the Δlpp Δpla double mutant were equally efficient in their uptake of zymosan particles as determined by flow cytometric analysis. Overall, our data indicated that although the Δlpp Δpla double mutant of Y. pestis CO92 was highly attenuated, it retained the ability to elicit innate and subsequent acquired immune

Mesenchymal stem cell-educated macrophages

OpenAIRE

Eggenhofer Elke; Hoogduijn Martin J

2012-01-01

Abstract Mesenchymal stem cells (MSC) mediate their immunosuppressive effects via a variety of mechanisms. One of these mechanisms involves the induction of macrophages with immunomodulatory capacities. This effect of MSC may be exploited when MSC are used as a cell therapeutic product. Furthermore, MSC are resident in tissues where they may locally target infiltrating macrophages to adapt more regulatory properties. The present review discusses the interaction between MSC and macrophages, th...

Protective role of benfotiamine, a fat-soluble vitamin B1 analogue, in lipopolysaccharide-induced cytotoxic signals in murine macrophages.

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Yadav, Umesh C S; Kalariya, Nilesh M; Srivastava, Satish K; Ramana, Kota V

2010-05-15

This study was designed to investigate the molecular mechanisms by which benfotiamine, a lipid-soluble analogue of vitamin B1, affects lipopolysaccharide (LPS)-induced inflammatory signals leading to cytotoxicity in the mouse macrophage cell line RAW264.7. Benfotiamine prevented LPS-induced apoptosis, expression of the Bcl-2 family of proapoptotic proteins, caspase-3 activation, and PARP cleavage and altered mitochondrial membrane potential and release of cytochrome c and apoptosis-inducing factor and phosphorylation and subsequent activation of p38-MAPK, stress-activated kinases (SAPK/JNK), protein kinase C, and cytoplasmic phospholipase A2 in RAW cells. Further, phosphorylation and degradation of inhibitory kappaB and consequent activation and nuclear translocation of the redox-sensitive transcription factor NF-kappaB were significantly prevented by benfotiamine. The LPS-induced increased expression of cytokines and chemokines and the inflammatory marker proteins iNOS and COX-2 and their metabolic products NO and PGE(2) was also blocked significantly. Thus, our results elucidate the molecular mechanism of the anti-inflammatory action of benfotiamine in LPS-induced inflammation in murine macrophages. Benfotiamine suppresses oxidative stress-induced NF-kappaB activation and prevents bacterial endotoxin-induced inflammation, indicating that vitamin B1 supplementation could be beneficial in the treatment of inflammatory diseases. Copyright 2010 Elsevier Inc. All rights reserved.

Nucleoside uptake in macrophages from various murine strains: a short-time and a two-step stimulation model

International Nuclear Information System (INIS)

Busolo, F.; Conventi, L.; Grigolon, M.; Palu, G.

1991-01-01

Kinetics of [3H]-uridine uptake by murine peritoneal macrophages (pM phi) is early altered after exposure to a variety of stimuli. Alterations caused by Candida albicans, lipopolysaccharide (LPS) and recombinant interferon-gamma (rIFN-gamma) were similar in SAVO, C57BL/6, C3H/HeN and C3H/HeJ mice, and were not correlated with an activation process as shown by the amount of tumor necrosis factor-alpha (TNF-alpha) being released. Short-time exposure to all stimuli resulted in an increased nucleoside uptake by SAVO pM phi, suggesting that the tumoricidal function of this cell either depends from the type of stimulus or the time when the specific interaction with the cell receptor is taking place. Experiments with priming and triggering signals confirmed the above findings, indicating that the increase or the decrease of nucleoside uptake into the cell depends essentially on the chemical nature of the priming stimulus. The triggering stimulus, on the other hand, is only able to amplify the primary response

Transferrin-derived synthetic peptide induces highly conserved pro-inflammatory responses of macrophages.

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Haddad, George; Belosevic, Miodrag

2009-02-01

We examined the induction of macrophage pro-inflammatory responses by transferrin-derived synthetic peptide originally identified following digestion of transferrin from different species (murine, bovine, human N-lobe and goldfish) using elastase. The mass spectrometry analysis of elastase-digested murine transferrin identified a 31 amino acid peptide located in the N2 sub-domain of the transferrin N-lobe, that we named TMAP. TMAP was synthetically produced and shown to induce a number of pro-inflammatory genes by quantitative PCR. TMAP induced chemotaxis, a potent nitric oxide response, and TNF-alpha secretion in different macrophage populations; P338D1 macrophage-like cells, mouse peritoneal macrophages, mouse bone marrow-derived macrophages (BMDM) and goldfish macrophages. The treatment of BMDM cultures with TMAP stimulated the production of nine cytokines and chemokines (IL-6, MCP-5, MIP-1 alpha, MIP-1 gamma, MIP-2, GCSF, KC, VEGF, and RANTES) that was measured using cytokine antibody array and confirmed by Western blot. Our results indicate that transferrin-derived peptide, TMAP, is an immunomodulating molecule capable of inducing pro-inflammatory responses in lower and higher vertebrates.

MURINE PULMONARY MACROPHAGE EXPRESSION AND PRODUCTION OF TNFA AND MIP-2 AFTER EXPOSURE TO DIESEL EXHAUST PARTICLES (DEP) AND EXTRACTS

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DEP constitute an important fraction of particulate air pollution and have been shown to cause inflammation of the airways. The aim of this study was to investigate the inflammatory cytokine response of alveolar macrophages exposed to DEP and DEP-extracts. A murine alveolar macr...

Fibronectin induces macrophage migration through a SFK-FAK/CSF-1R pathway.

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Digiacomo, Graziana; Tusa, Ignazia; Bacci, Marina; Cipolleschi, Maria Grazia; Dello Sbarba, Persio; Rovida, Elisabetta

2017-07-04

Integrins, following binding to proteins of the extracellular matrix (ECM) including collagen, laminin and fibronectin (FN), are able to transduce molecular signals inside the cells and to regulate several biological functions such as migration, proliferation and differentiation. Besides activation of adaptor molecules and kinases, integrins transactivate Receptor Tyrosine Kinases (RTK). In particular, adhesion to the ECM may promote RTK activation in the absence of growth factors. The Colony-Stimulating Factor-1 Receptor (CSF-1R) is a RTK that supports the survival, proliferation, and motility of monocytes/macrophages, which are essential components of innate immunity and cancer development. Macrophage interaction with FN is recognized as an important aspect of host defense and wound repair. The aim of the present study was to investigate on a possible cross-talk between FN-elicited signals and CSF-1R in macrophages. FN induced migration in BAC1.2F5 and J774 murine macrophage cell lines and in human primary macrophages. Adhesion to FN determined phosphorylation of the Focal Adhesion Kinase (FAK) and Src Family Kinases (SFK) and activation of the SFK/FAK complex, as witnessed by paxillin phosphorylation. SFK activity was necessary for FAK activation and macrophage migration. Moreover, FN-induced migration was dependent on FAK in either murine macrophage cell lines or human primary macrophages. FN also induced FAK-dependent/ligand-independent CSF-1R phosphorylation, as well as the interaction between CSF-1R and β1. CSF-1R activity was necessary for FN-induced macrophage migration. Indeed, genetic or pharmacological inhibition of CSF-1R prevented FN-induced macrophage migration. Our results identified a new SFK-FAK/CSF-1R signaling pathway that mediates FN-induced migration of macrophages.

Effect of Shark Liver Oil on Peritoneal Murine Macrophages in Responses to Killed-Candida albicans

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Monire Hajimoradi

2009-09-01

Full Text Available Objective(sShark Liver Oil (SLO is an immunomodulator. Macrophages play a key role in host defense against pathogens like fungi. Candida albicans have mechanisms to escape immune system. We determined the effect of killed-Candida on the in vitro viability of macrophages and the effect of SLO on augmentation of this potency.Materials and MethodsPeritoneal macrophages were separated and cultured (3×105/well. At first, the effect of killed-Candida (200 cells/well on macrophage viability was evaluated, using MTT test. Then, MTT was performed on macrophages stimulated with killed-Candida in the presence of SLO. ResultsKilled-Candida suppressed the ability of MTT reduction and hence macrophages viability (P=0.026, but addition of SLO (100 mg/ml significantly enhanced cell viability (P=0.00. So, SLO could neutralize the inhibitory effect of Candida.ConclusionSimultaneous with cytotoxic effect of killed-Candida cells on macrophages viability, SLO augment macrophages viability. So, it can be applied in candidiasis as a complement.

Production and Functional Characterization of Murine Osteoclasts Differentiated from ER-Hoxb8-Immortalized Myeloid Progenitor Cells.

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Frank Zach

Full Text Available In vitro differentiation into functional osteoclasts is routinely achieved by incubation of embryonic stem cells, induced pluripotent stem cells, or primary as well as cryopreserved spleen and bone marrow-derived cells with soluble receptor activator of nuclear factor kappa-B ligand and macrophage colony-stimulating factor. Additionally, osteoclasts can be derived from co-cultures with osteoblasts or by direct administration of soluble receptor activator of nuclear factor kappa-B ligand to RAW 264.7 macrophage lineage cells. However, despite their benefits for osteoclast-associated research, these different methods have several drawbacks with respect to differentiation yields, time and animal consumption, storage life of progenitor cells or the limited potential for genetic manipulation of osteoclast precursors. In the present study, we therefore established a novel protocol for the differentiation of osteoclasts from murine ER-Hoxb8-immortalized myeloid stem cells. We isolated and immortalized bone marrow cells from wild type and genetically manipulated mouse lines, optimized protocols for osteoclast differentiation and compared these cells to osteoclasts derived from conventional sources. In vitro generated ER-Hoxb8 osteoclasts displayed typical osteoclast characteristics such as multi-nucleation, tartrate-resistant acid phosphatase staining of supernatants and cells, F-actin ring formation and bone resorption activity. Furthermore, the osteoclast differentiation time course was traced on a gene expression level. Increased expression of osteoclast-specific genes and decreased expression of stem cell marker genes during differentiation of osteoclasts from ER-Hoxb8-immortalized myeloid progenitor cells were detected by gene array and confirmed by semi-quantitative and quantitative RT-PCR approaches. In summary, we established a novel method for the quantitative production of murine bona fide osteoclasts from ER-Hoxb8 stem cells generated from

Proliferation differentiation and therapeutic effect of short-term cultured murine bone marrow cells

International Nuclear Information System (INIS)

Zhao Zekun; Cong Jianbo

1986-01-01

Murine bone marrow cells were cultured in conditioned medium of muscle. After 24 hours of culture, both adherent and suspended cells appeared in the culture. The adherent cells mainly consisted of macrophages and the suspended cells were predominantly granulocytes. After 6 days, the total number of nucleated cells and CFU-C in the culture increased about 400% and 600% respectively, but CFU-S reduced to 21% approximately. Lymphocytes persisted only for 4 days. The stem cells (CFU-S) from 6-day culture were injected into the lethally irradiated syngenic mice. The 30 day survival rate of the treated mice was 89% whereas that of the controls was only 7%. The bone marrow cells in 2/8 of recipients sacrificed at 30 or 60 days were of donor type and 6/8 of the recipients were chimeras

Salivary gland extracts of Culicoides sonorensis inhibit murine lymphocyte proliferation and no production by macrophages.

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Bishop, Jeanette V; Mejia, J Santiago; Pérez de León, Adalberto A; Tabachnick, Walter J; Titus, Richard G

2006-09-01

Culicoides biting midges serve as vectors of pathogens affecting humans and domestic animals. Culicoides sonorensis is a vector of several arboviruses in North American that cause substantial economic losses to the US livestock industry. Previous studies showed that C. sonorensis saliva, like the saliva of many hematophagous arthropods, contains numerous pharmacological agents that affect hemostasis and early events in the inflammatory response, which may enhance the infectivity of Culicoides-borne pathogens. This paper reports on the immunomodulatory properties of C. sonorensis salivary gland extracts on murine immune cells and discusses the possible immunomodulatory role of C. sonorensis saliva in vesicular stomatitis virus infection of vertebrate hosts. Splenocytes treated with C. sonorensis mitogens were significantly affected in their proliferative response, and peritoneal macrophages secreted significantly less NO. A 66-kDa glycoprotein was purified from C. sonorensis salivary gland extract, which may be in part responsible for these observations and may be considered as a vaccine candidate.

Regulation of macrophage accessory cell activity by mycobacteria. I. Ia expression in normal and irradiated mice infected with Mycobacterium mycroti

International Nuclear Information System (INIS)

Kaye, P.M.; Feldmann, M.

1986-01-01

CBA/Ca mice were infected by either the intravenous or intraperitoneal route with Mycobacterium microti and the subsequent changes in local macrophage populations examined. Following infection, the number of macrophages increased and they showed greater expression of both MHC Class II molecules. This response was not dependent on viability of the mycobacteria, in contrast to reports with other microorganisms such as Listeria. Studies in sublethally irradiated mice indicated that persistent antigen could give rise to a response after a period of host recovery which was radiation dose dependent. This procedure also highlighted differences in the regulation of different murine class II antigens in vivo, as seen by delayed re-expression of I-E antigens. Macrophage accessory cell function, as assessed by an in vitro T cell proliferation assay, correlated with Ia expression after fixation, but not after indomethacin treatment; this highlights the diverse nature of regulatory molecules produced by these cells. (author)

Activated prostaglandin D2 receptors on macrophages enhance neutrophil recruitment into the lung

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Jandl, Katharina; Stacher, Elvira; Bálint, Zoltán; Sturm, Eva Maria; Maric, Jovana; Peinhaupt, Miriam; Luschnig, Petra; Aringer, Ida; Fauland, Alexander; Konya, Viktoria; Dahlen, Sven-Erik; Wheelock, Craig E.; Kratky, Dagmar; Olschewski, Andrea; Marsche, Gunther; Schuligoi, Rufina; Heinemann, Akos

2016-01-01

Background Prostaglandin (PG) D2 is an early-phase mediator in inflammation, but its action and the roles of the 2 D-type prostanoid receptors (DPs) DP1 and DP2 (also called chemoattractant receptor–homologous molecule expressed on TH2 cells) in regulating macrophages have not been elucidated to date. Objective We investigated the role of PGD2 receptors on primary human macrophages, as well as primary murine lung macrophages, and their ability to influence neutrophil action in vitro and in vivo. Methods In vitro studies, including migration, Ca2+ flux, and cytokine secretion, were conducted with primary human monocyte-derived macrophages and neutrophils and freshly isolated murine alveolar and pulmonary interstitial macrophages. In vivo pulmonary inflammation was assessed in male BALB/c mice. Results Activation of DP1, DP2, or both receptors on human macrophages induced strong intracellular Ca2+ flux, cytokine release, and migration of macrophages. In a murine model of LPS-induced pulmonary inflammation, activation of each PGD2 receptor resulted in aggravated airway neutrophilia, tissue myeloperoxidase activity, cytokine contents, and decreased lung compliance. Selective depletion of alveolar macrophages abolished the PGD2-enhanced inflammatory response. Activation of PGD2 receptors on human macrophages enhanced the migratory capacity and prolonged the survival of neutrophils in vitro. In human lung tissue specimens both DP1 and DP2 receptors were located on alveolar macrophages along with hematopoietic PGD synthase, the rate-limiting enzyme of PGD2 synthesis. Conclusion For the first time, our results show that PGD2 markedly augments disease activity through its ability to enhance the proinflammatory actions of macrophages and subsequent neutrophil activation. PMID:26792210

4-Hydroxynonenal enhances MMP-9 production in murine macrophages via 5-lipoxygenase-mediated activation of ERK and p38 MAPK

International Nuclear Information System (INIS)

Lee, Seung J.; Kim, Chae E.; Yun, Mi R.; Seo, Kyo W.; Park, Hye M.; Yun, Jung W.; Shin, Hwa K.; Bae, Sun S.; Kim, Chi D.

2010-01-01

Exaggerated levels of 4-hydroxynonenal (HNE) and 5-lipoxygenase (5-LO) co-exist in macrophages in atherosclerotic lesions, and activated macrophages produce MMP-9 that degrades atherosclerotic plaque constituents. This study investigated the effects of HNE on MMP-9 production, and the potential role for 5-LO derivatives in MMP-9 production in murine macrophages. Stimulation of J774A.1 cells with HNE led to activation of 5-LO, as measured by leukotriene B 4 (LTB 4 ) production. This was associated with an increased production of MMP-9, which was blunted by inhibition of 5-LO with MK886, a 5-LO inhibitor or with 5-LO siRNA. A cysteinyl-LT 1 (cysLT 1 ) receptor antagonist, REV-5901 as well as a BLT 1 receptor antagonist, U-75302, also attenuated MMP-9 production induced by HNE. Furthermore, LTB 4 and cysLT (LTC 4 and LTD 4 ) enhanced MMP-9 production in macrophages, suggesting a pivotal role for 5-LO in HNE-mediated production of MMP-9. Among the MAPK pathways, LTB 4 and cysLT enhanced phosphorylation of ERK and p38 MAPK, but not JNK. Linked to these results, a p38 MAPK inhibitor as well as an ERK inhibitor blunted MMP-9 production induced by LT. Collectively, these data suggest that 5-LO-derived LT mediates HNE-induced MMP-9 production via activation of ERK and p38 MAPK pathways, consequently leading to plaque instability in atherosclerosis.

Helicobacter pylori protein HP0986 (TieA) interacts with mouse TNFR1 and triggers proinflammatory and proapoptotic signaling pathways in cultured macrophage cells (RAW 264.7).

Science.gov (United States)

Ansari, Suhail A; Devi, Savita; Tenguria, Shivendra; Kumar, Ashutosh; Ahmed, Niyaz

2014-08-01

HP0986 protein of Helicobacter pylori has been shown to trigger induction of proinflammatory cytokines (IL-8 and TNF-α) through the activation of NF-κB and also to induce Fas mediated apoptosis of human macrophage cells (THP-1). In this study, we unravel mechanistic details of the biological effects of this protein in a murine macrophage environment. Up regulation of MCP-1 and TNF-α in HP0986-induced RAW 264.7 cells occurred subsequent to the activation and translocation of NF-κB to the cell nucleus. Further, HP0986 induced apoptosis of RAW 264.7 cells through Fas activation and this was in agreement with previous observations made with THP-1 cells. Our studies indicated activation of TNFR1 through interaction with HP0986 and this elicited the aforementioned responses independent of TLR2, TLR4 or TNFR2. We found that mouse TNFR1 activation by HP0986 facilitates formation of a complex comprising of TNFR1, TRADD and TRAF2, and this occurs upstream of NF-κB activation. Furthermore, FADD also forms a second complex, at a later stage, together with TNFR1 and TRADD, resulting in caspase-8 activation and thereby the apoptosis of RAW 264.7 cells. In summary, our observations reveal finer details of the functional activity of HP0986 protein in relation to its behavior in a murine macrophage cell environment. These findings reconfirm the proinflammatory and apoptotic role of HP0986 signifying it to be an important trigger of innate responses. These observations form much needed baseline data entailing future in vivo studies of the functions of HP0986 in a murine model. Copyright © 2014 Elsevier Ltd. All rights reserved.

Protective role of benfotiamine, a fat soluble vitamin B1 analogue, in the lipopolysaccharide–induced cytotoxic signals in murine macrophages

Science.gov (United States)

Yadav, Umesh C S; Kalariya, Nilesh M; Srivastava, Satish K; Ramana, Kota V

2010-01-01

The study has been designed to investigate the molecular mechanisms by which benfotiamine, a lipid-soluble analogue of Vitamin B1 effects lipopolysaccharide (LPS) – induced inflammatory signals leading to cytotoxicity in mouse macrophage cell line RAW264.7. Benfotiamine prevented LPS-induced apoptosis, expression of Bcl-2 family of pro-apoptotic proteins, caspase-3 activation and PARP cleavage, altered mitochondrial membrane potential and release of cytochrome-c and apoptosis inducing factor (AIF), phosphorylation and subsequent activation of p38-MAPK, stress activated kinases (SAPK/JNK), Protein kinase C, and cytoplasmic-phospholipase A2 in RAW cells. Further, phosphorylation and degradation of inhibitory kappa B (IκB) and consequent activation and nuclear translocation of redox-sensitive transcription factor NF-κB was significantly prevented by benfotiamine. The LPS-induced increased expression of cytokines and chemokines and other inflammatory marker proteins iNOS and COX-2 and their metabolic products NO and PGE2 were also blocked significantly. Thus, our results elucidate the molecular mechanism of anti-inflammatory action of benfotiamine in LPS-induced inflammation in murine macrophage. Benfotiamine suppresses oxidative stress-induced NF-κB activation and prevents the bacterial endotoxin-induced inflammation indicating that vitamin B1 supplementation could be beneficial in the treatment of inflammatory diseases. PMID:20219672

Fisetin antagonizes cell fusion, cytoskeletal organization and bone resorption in RANKL-differentiated murine macrophages.

Science.gov (United States)

Kim, Yun-Ho; Kim, Jung-Lye; Lee, Eun-Jung; Park, Sin-Hye; Han, Seon-Young; Kang, Soon Ah; Kang, Young-Hee

2014-03-01

Osteoclastogenesis is comprised of several stage s including progenitor survival, differentiation to mononuclear preosteoclasts, cell fusion to multinuclear mature osteoclasts, and activation to osteoclasts with bone resorbing activity. Botanical antioxidants are now being increasingly investigated for their health-promoting effects on bone. This study investigated that fisetin, a flavonol found naturally in many fruits and vegetables, suppressed osteoclastogenesis by disturbing receptor activator of nuclear factor (NF)-κB ligand (RANKL)-mediated signaling pathway and demoting osteoclastogenic protein induction. Nontoxic fisetin at ≤10 μM inhibited the induction of RANK, tumor necrosis factor receptor associated factor 6 (TRAF6) and the activation of NF-κB in RANKL-stimulated RAW 264.7 macrophages. In RANKL-differentiated osteoclasts cell fusion protein of E-cadherin was induced, which was dampened by fisetin. The formation of tartrate-resistance acid phosphatase-positive multinucleated osteoclasts was suppressed by adding fisetin to RANKL-exposed macrophages. It was also found that fisetin reduced actin ring formation and gelsolin induction of osteclasts enhanced by RANKL through disturbing c-Src-proline-rich tyrosine kinase 2 signaling. Fisetin deterred preosteoclasts from the cell-cell fusion and the organization of the cytoskeleton to seal the resorbing area and to secret protons for bone resorption. Consistently, the 5 day-treatment of fisetin diminished RANKL-induced cellular expression of carbonic anhydrase II and integrin β3 concurrently with a reduction of osteoclast bone-resorbing activity. Therefore, fisetin was a natural therapeutic agent retarding osteoclast fusion and cytoskeletal organization such as actin rings and ruffled boarder, which is a property of mature osteoclasts and is required for osteoclasts to resorb bone. Copyright © 2014 Elsevier Inc. All rights reserved.

Adenosine derived from Staphylococcus aureus-engulfed macrophages functions as a potent stimulant for the induction of inflammatory cytokines in mast cells

DEFF Research Database (Denmark)

Ma, Ying Jie; Kim, Chan-Hee; Ryu, Kyoung-Hwa

2011-01-01

In this study, we attempted to isolate novel mast cell-stimulating molecules from Staphylococcus aureus. Water-soluble extract of S. aureus cell lysate strongly induced human interleukin- 8 in human mast cell line-1 and mouse interleukin-6 in mouse bone marrow-derived mast cells. The active...... adenosine receptor blocker, verified that purified adenosine can induce interleukin-8 production via adenosine receptors on mast cells. Moreover, adenosine was purified from S. aureusengulfed RAW264.7 cells, a murine macrophage cell line, used to induce phagocytosis of S. aureus. These results show a novel...

Nicotine Impairs Macrophage Control of Mycobacterium tuberculosis.

Science.gov (United States)

Bai, Xiyuan; Stitzel, Jerry A; Bai, An; Zambrano, Cristian A; Phillips, Matthew; Marrack, Philippa; Chan, Edward D

2017-09-01

Pure nicotine impairs macrophage killing of Mycobacterium tuberculosis (MTB), but it is not known whether the nicotine component in cigarette smoke (CS) plays a role. Moreover, the mechanisms by which nicotine impairs macrophage immunity against MTB have not been explored. To neutralize the effects of nicotine in CS extract, we used a competitive inhibitor to the nicotinic acetylcholine receptor (nAChR)-mecamylamine-as well as macrophages derived from mice with genetic disruption of specific subunits of nAChR. We also determined whether nicotine impaired macrophage autophagy and whether nicotine-exposed T regulatory cells (Tregs) could subvert macrophage anti-MTB immunity. Mecamylamine reduced the CS extract increase in MTB burden by 43%. CS extract increase in MTB was also significantly attenuated in macrophages from mice with genetic disruption of either the α7, β2, or β4 subunit of nAChR. Nicotine inhibited autophagosome formation in MTB-infected THP-1 cells and primary murine alveolar macrophages, as well as increased the intracellular MTB burden. Nicotine increased migration of THP-1 cells, consistent with the increased number of macrophages found in the lungs of smokers. Nicotine induced Tregs to produce transforming growth factor-β. Naive mouse macrophages co-cultured with nicotine-exposed Tregs had significantly greater numbers of viable MTB recovered with increased IL-10 production and urea production, but no difference in secreted nitric oxide as compared with macrophages cocultured with unexposed Tregs. We conclude that nicotine in CS plays an important role in subverting macrophage control of MTB infection.

Toll like receptor 4 (TLR4) mediates the stimulating activities of chitosan oligosaccharide on macrophages.

Science.gov (United States)

Zhang, Pei; Liu, Weizhi; Peng, Yanfei; Han, Baoqin; Yang, Yan

2014-11-01

The in vivo and in vitro immunostimulating properties of chitosan oligosaccharide (COS) prepared by enzymatic hydrolysis of chitosan and the mechanisms mediating the effects were investigated. Our data showed that the highly active chitosanase isolated could hydrolyze chitosan to the polymerization degree of 3-8. The resulting COS was an efficient immunostimulator. COS markedly enhanced the proliferation and neutral red phagocytosis by RAW 264.7 macrophages. The production of nitric oxide (NO) and tumor necrosis factor alpha (TNF-α) by macrophages was significantly increased after incubation with COS. Oral administration of COS in mice could increase spleen index and serum immunoglobin G (IgG) contents. COS was labeled with FITC to study the pinocytosis by macrophages. Results showed that FITC-COS was phagocyted by macrophages and anti-murine TLR4 antibody completely blocked FITC-COS pinocytosis. RT-PCR indicated that COS treatment of macrophages significantly increased TLR4 and inducible nitric oxide synthase (iNOS) mRNA levels. When cells were pretreated with anti-murine TLR4 antibody, the effect of COS on TLR4 and iNOS mRNA induction was decreased. COS-induced NO secretion by macrophages was also markedly decreased by anti-murine TLR4 antibody pretreatment. In conclusion, the present study revealed that COS possesses potent immune-stimulating properties by activating TLR4 on macrophages. Copyright © 2014 Elsevier B.V. All rights reserved.

Cell Elasticity Determines Macrophage Function

Science.gov (United States)

Patel, Naimish R.; Bole, Medhavi; Chen, Cheng; Hardin, Charles C.; Kho, Alvin T.; Mih, Justin; Deng, Linhong; Butler, James; Tschumperlin, Daniel; Fredberg, Jeffrey J.; Krishnan, Ramaswamy; Koziel, Henry

2012-01-01

Macrophages serve to maintain organ homeostasis in response to challenges from injury, inflammation, malignancy, particulate exposure, or infection. Until now, receptor ligation has been understood as being the central mechanism that regulates macrophage function. Using macrophages of different origins and species, we report that macrophage elasticity is a major determinant of innate macrophage function. Macrophage elasticity is modulated not only by classical biologic activators such as LPS and IFN-γ, but to an equal extent by substrate rigidity and substrate stretch. Macrophage elasticity is dependent upon actin polymerization and small rhoGTPase activation, but functional effects of elasticity are not predicted by examination of gene expression profiles alone. Taken together, these data demonstrate an unanticipated role for cell elasticity as a common pathway by which mechanical and biologic factors determine macrophage function. PMID:23028423

Cell elasticity determines macrophage function.

Directory of Open Access Journals (Sweden)

Naimish R Patel

Full Text Available Macrophages serve to maintain organ homeostasis in response to challenges from injury, inflammation, malignancy, particulate exposure, or infection. Until now, receptor ligation has been understood as being the central mechanism that regulates macrophage function. Using macrophages of different origins and species, we report that macrophage elasticity is a major determinant of innate macrophage function. Macrophage elasticity is modulated not only by classical biologic activators such as LPS and IFN-γ, but to an equal extent by substrate rigidity and substrate stretch. Macrophage elasticity is dependent upon actin polymerization and small rhoGTPase activation, but functional effects of elasticity are not predicted by examination of gene expression profiles alone. Taken together, these data demonstrate an unanticipated role for cell elasticity as a common pathway by which mechanical and biologic factors determine macrophage function.

Chronic skin inflammation accelerates macrophage cholesterol crystal formation and atherosclerosis

Science.gov (United States)

Ng, Qimin; Sanda, Gregory E.; Dey, Amit K.; Teague, Heather L.; Sorokin, Alexander V.; Dagur, Pradeep K.; Silverman, Joanna I.; Harrington, Charlotte L.; Rodante, Justin A.; Rose, Shawn M.; Varghese, Nevin J.; Belur, Agastya D.; Goyal, Aditya; Gelfand, Joel M.; Springer, Danielle A.; Bleck, Christopher K.E.; Thomas, Crystal L.; Yu, Zu-Xi; Winge, Mårten C.G.; Kruth, Howard S.; Marinkovich, M. Peter; Joshi, Aditya A.; Playford, Martin P.; Mehta, Nehal N.

2018-01-01

Inflammation is critical to atherogenesis. Psoriasis is a chronic inflammatory skin disease that accelerates atherosclerosis in humans and provides a compelling model to understand potential pathways linking these diseases. A murine model capturing the vascular and metabolic diseases in psoriasis would accelerate our understanding and provide a platform to test emerging therapies. We aimed to characterize a new murine model of skin inflammation (Rac1V12) from a cardiovascular standpoint to identify novel atherosclerotic signaling pathways modulated in chronic skin inflammation. The RacV12 psoriasis mouse resembled the human disease state, including presence of systemic inflammation, dyslipidemia, and cardiometabolic dysfunction. Psoriasis macrophages had a proatherosclerotic phenotype with increased lipid uptake and foam cell formation, and also showed a 6-fold increase in cholesterol crystal formation. We generated a triple-genetic K14-RacV12–/+/Srb1–/–/ApoER61H/H mouse and confirmed psoriasis accelerates atherogenesis (~7-fold increase). Finally, we noted a 60% reduction in superoxide dismutase 2 (SOD2) expression in human psoriasis macrophages. When SOD2 activity was restored in macrophages, their proatherogenic phenotype reversed. We demonstrate that the K14-RacV12 murine model captures the cardiometabolic dysfunction and accelerates vascular disease observed in chronic inflammation and that skin inflammation induces a proatherosclerotic macrophage phenotype with impaired SOD2 function, which associated with accelerated atherogenesis. PMID:29321372

Stimulation of Inducible Nitric Oxide Synthase Expression by Beta Interferon Increases Necrotic Death of Macrophages upon Listeria monocytogenes Infection▿

OpenAIRE

Zwaferink, Heather; Stockinger, Silvia; Reipert, Siegfried; Decker, Thomas

2008-01-01

Murine macrophage death upon infection with Listeria monocytogenes was previously shown to be increased by beta interferon, produced by the infected cells. We saw that interferon-upregulated caspase activation or other interferon-inducible, death-associated proteins, including TRAIL, protein kinase R, and p53, were not necessary for cell death. Macrophage death was reduced when inducible nitric oxide synthase (iNOS) was inhibited during infection, and iNOS-deficient macrophages were less susc...

DMPD: CSF-1 and cell cycle control in macrophages. [Dynamic Macrophage Pathway CSML Database

Lifescience Database Archive (English)

Full Text Available 8981359 CSF-1 and cell cycle control in macrophages. Hamilton JA. Mol Reprod Dev. 1...997 Jan;46(1):19-23. (.png) (.svg) (.html) (.csml) Show CSF-1 and cell cycle control in macrophages. PubmedI...D 8981359 Title CSF-1 and cell cycle control in macrophages. Authors Hamilton JA. Publication Mol Reprod Dev

Human Induced Pluripotent Stem Cell-Derived Macrophages Share Ontogeny with MYB-Independent Tissue-Resident Macrophages

Directory of Open Access Journals (Sweden)

Julian Buchrieser

2017-02-01

Full Text Available Tissue-resident macrophages, such as microglia, Kupffer cells, and Langerhans cells, derive from Myb-independent yolk sac (YS progenitors generated before the emergence of hematopoietic stem cells (HSCs. Myb-independent YS-derived resident macrophages self-renew locally, independently of circulating monocytes and HSCs. In contrast, adult blood monocytes, as well as infiltrating, gut, and dermal macrophages, derive from Myb-dependent HSCs. These findings are derived from the mouse, using gene knockouts and lineage tracing, but their applicability to human development has not been formally demonstrated. Here, we use human induced pluripotent stem cells (iPSCs as a tool to model human hematopoietic development. By using a CRISPR-Cas9 knockout strategy, we show that human iPSC-derived monocytes/macrophages develop in an MYB-independent, RUNX1-, and SPI1 (PU.1-dependent fashion. This result makes human iPSC-derived macrophages developmentally related to and a good model for MYB-independent tissue-resident macrophages, such as alveolar and kidney macrophages, microglia, Kupffer cells, and Langerhans cells.

Leishmania resistant to sodium stibogluconate: drug-associated macrophage-dependent killing

DEFF Research Database (Denmark)

Ibrahim, M E; Hag-Ali, M; el-Hassan, A M

1994-01-01

A total of 17 Leishmania isolates, 6 of them isolated from antimony-resistant patients, were collected in the Sudan and tested for their sensitivity to sodium stibogluconate (Pentostam) as promastigotes. Six of those isolates were tested as amastigotes infecting a murine macrophage cell line...

Yersinia pestis and host macrophages: immunodeficiency of mouse macrophages induced by YscW.

Science.gov (United States)

Bi, Yujing; Du, Zongmin; Han, Yanping; Guo, Zhaobiao; Tan, Yafang; Zhu, Ziwen; Yang, Ruifu

2009-09-01

The virulence of the pathogenic Yersinia species depends on a plasmid-encoded type III secretion system (T3SS) that transfers six Yersinia outer protein (Yop) effector proteins into the cytoplasm of eukaryotic cells, leading to disruption of host defence mechanisms. It is shown in this study that Yersinia pestis YscW, a protein of the T3SS injectisome, contributes to the induction of a deficiency in phagocytosis in host macrophages and a reduction in their antigen-presenting capacity. A Y. pestis strain lacking yscW had no effect on uptake by host macrophages. In mice infected with wild-type Y. pestis, the yscW mutant or a complement strain, immunodeficiency was observed in host macrophages compared with those from uninfected mice. However, the phagocytosis and antigen presenting capacities of macrophages infected by yscW mutant strain both in vivo and in vitro were significantly higher than those by wild type strain. Consistent with this finding, when YscW was expressed in the RAW264.7 macrophage cell line, phagocytosis and antigen-presenting capacities were significantly lower than those of the control groups. These results indicate that Y. pestis YscW may directly induce immunodeficiency in murine macrophages by crippling their phagocytosis and antigen-presenting capacities. These data provide evidences to Y. pestis pathogenesis that some proteins in T3SS injectisome, such as YscW protein, might play independent roles in disrupting host defense apart from their known functions.

Iron oxide nanoparticles surface coating and cell uptake affect biocompatibility and inflammatory responses of endothelial cells and macrophages

Energy Technology Data Exchange (ETDEWEB)

Orlando, Antonina [University of Milano-Bicocca, Department of Health Sciences (Italy); Colombo, Miriam; Prosperi, Davide [University of Milano-Bicocca, Department of Biotechnology and Biosciences (Italy); Gregori, Maria; Panariti, Alice; Rivolta, Ilaria; Masserini, Massimo; Cazzaniga, Emanuela, E-mail: emanuela.cazzaniga@unimib.it [University of Milano-Bicocca, Department of Health Sciences (Italy)

2015-09-15

Engineered iron oxide nanoparticles (IONP) offer the possibility of a wide range of medical uses, from clinical imaging to magnetically based hyperthermia for tumor treatment. These applications require their systemic administration in vivo. An important property of nanoparticles is their stability in biological media. For this purpose, a multicomponent nanoconstruct combining high colloidal stability and improved physical properties was synthesized and characterized. IONP were coated with an amphiphilic polymer (PMA), which confers colloidal stability, and were pegylated in order to obtain the nanoconstruct PEG-IONP-PMA. The aim of this study was to utilize cultured human endothelial cells (HUVEC) and murine macrophages, taken as model of cells exposed to NP after systemic administration, to assess the biocompatibility of PEG-IONP-PMA (23.1 ± 1.4 nm) or IONP-PMA (15.6 ± 3.4 nm). PEG-IONP-PMA, tested at different concentrations as high as 20 μg mL{sup −1}, exhibited no cytotoxicity or inflammatory responses. By contrast, IONP-PMA showed a concentration-dependent increase of cytotoxicity and of TNF-α production by macrophages and NO production by HUVECs. Cell uptake analysis suggested that after PEGylation, IONP were less internalized either by macrophages or by HUVEC. These results suggest that the choice of the polymer and the chemistry of surface functionalization are a crucial feature to confer to IONP biocompatibility.

Immunomodulatory Role of Ocimum gratissimum and Ascorbic Acid against Nicotine-Induced Murine Peritoneal Macrophages In Vitro

Directory of Open Access Journals (Sweden)

Santanu Kar Mahapatra

2011-01-01

Full Text Available The aim of this present study was to evaluate the immune functions and immune responses in nicotine-induced (10 mM macrophages and concurrently establish the immunomodulatory role of aqueous extract of Ocimum gratissimum (Ae-Og and ascorbic acid. In this study, nitrite generations and some phenotype functions by macrophages were studied. Beside that, release of Th1 cytokines (TNF-α, IL-12 and Th2 cytokines (IL-10, TGF-β was measured by ELISA, and the expression of these cytokines at mRNA level was analyzed by real-time PCR. Ae-Og, at a dose of 10 μg/mL, significantly reduced the nicotine-induced NO generation and iNOSII expression. Similar kinds of response were observed with supplementation of ascorbic acid (0.01 mM. The administration of Ae-Og and ascorbic acid increased the decreased adherence, chemotaxis, phagocytosis, and intracellular killing of bacteria in nicotine-treated macrophages. Ae-Og and ascorbic acid were found to protect the murine peritoneal macrophages through downregulation of Th1 cytokines in nicotine-treated macrophages with concurrent activation of Th2 responses. These findings strongly enhanced our understanding of the molecular mechanism leading to nicotine-induced suppression of immune functions and provide additional rationale for application of anti-inflammatory therapeutic approaches by O. gratissimum and ascorbic acid for different inflammatory disease prevention and treatment during nicotine toxicity.

Unique proteomic signatures distinguish macrophages and dendritic cells.

Directory of Open Access Journals (Sweden)

Lev Becker

Full Text Available Monocytes differentiate into heterogeneous populations of tissue macrophages and dendritic cells (DCs that regulate inflammation and immunity. Identifying specific populations of myeloid cells in vivo is problematic, however, because only a limited number of proteins have been used to assign cellular phenotype. Using mass spectrometry and bone marrow-derived cells, we provided a global view of the proteomes of M-CSF-derived macrophages, classically and alternatively activated macrophages, and GM-CSF-derived DCs. Remarkably, the expression levels of half the plasma membrane proteins differed significantly in the various populations of cells derived in vitro. Moreover, the membrane proteomes of macrophages and DCs were more distinct than those of classically and alternatively activated macrophages. Hierarchical cluster and dual statistical analyses demonstrated that each cell type exhibited a robust proteomic signature that was unique. To interrogate the phenotype of myeloid cells in vivo, we subjected elicited peritoneal macrophages harvested from wild-type and GM-CSF-deficient mice to mass spectrometric and functional analysis. Unexpectedly, we found that peritoneal macrophages exhibited many features of the DCs generated in vitro. These findings demonstrate that global analysis of the membrane proteome can help define immune cell phenotypes in vivo.

Human Induced Pluripotent Stem Cell-Derived Macrophages for Unraveling Human Macrophage Biology.

Science.gov (United States)

Zhang, Hanrui; Reilly, Muredach P

2017-11-01

Despite a substantial appreciation for the critical role of macrophages in cardiometabolic diseases, understanding of human macrophage biology has been hampered by the lack of reliable and scalable models for cellular and genetic studies. Human induced pluripotent stem cell (iPSC)-derived macrophages (IPSDM), as an unlimited source of subject genotype-specific cells, will undoubtedly play an important role in advancing our understanding of the role of macrophages in human diseases. In this review, we summarize current literature in the differentiation and characterization of IPSDM at phenotypic, functional, and transcriptomic levels. We emphasize the progress in differentiating iPSC to tissue resident macrophages, and in understanding the ontogeny of in vitro differentiated IPSDM that resembles primitive hematopoiesis, rather than adult definitive hematopoiesis. We review the application of IPSDM in modeling both Mendelian genetic disorders and host-pathogen interactions. Finally, we highlighted the potential areas of research using IPSDM in functional validation of coronary artery disease loci in genome-wide association studies, functional genomic analyses, drug testing, and cell therapeutics in cardiovascular diseases. © 2017 American Heart Association, Inc.

FcγRI (CD64): an identity card for intestinal macrophages.

Science.gov (United States)

De Calisto, Jaime; Villablanca, Eduardo J; Mora, J Rodrigo

2012-12-01

Macrophages are becoming increasingly recognized as key cellular players in intestinal immune homeostasis. However, differentiating between macrophages and dendritic cells (DCs) is often difficult, and finding a specific phenotypic signature for intestinal macrophage identification has remained elusive. In this issue of the European Journal of Immunology, Tamoutounour et al. [Eur. J. Immunol. 2012. 42: 3150-3166] identify CD64 as a specific macrophage marker that can be used to discriminate DCs from macrophages in the murine small and large intestine, under both steady-state and inflammatory conditions. The authors also propose a sequential 'monocyte-waterfall' model for intestinal macrophage differentiation, with implications for immune tolerance and inflammation at the gut mucosal interface. This Commentary will discuss the advantages and potential limitations of CD64 as a marker for intestinal macrophages. © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Modulation of macrophage Ia expression by lipopolysaccharide: Stem cell requirements, accessory lymphocyte involvement, and IA-inducing factor production

International Nuclear Information System (INIS)

Wentworth, P.A.; Ziegler, H.K.

1989-01-01

The mechanism of induction of murine macrophage Ia expression by lipopolysaccharide (LPS) was studied. Intraperitoneal injection of 1 microgram of LPS resulted in a 3- to 10-fold increase in the number of IA-positive peritoneal macrophages (flow cytometry and immunofluorescence) and a 6-to 16-fold increase by radioimmunoassay. The isolated lipid A moiety of LPS was a potent inducer of macrophage Ia expression. Ia induction required a functional myelopoietic system as indicated by the finding that the response to LPS was eliminated in irradiated (900 rads) mice and reinstated by reconstitution with bone marrow cells. Comparison of LPS-induced Ia expression in normal and LPS-primed mice revealed a faster secondary response to LPS. The memory response could be adoptively transferred to normal mice with nonadherent spleen cells prepared 60 days after LPS injection. Spleen cells prepared 5 days after LPS injection caused Ia induction in LPS-nonresponder mice; such induction was not observed in irradiated (900 rads) recipients. The cell responsible for this phenomenon was identified as a Thy-1+, immunoglobulin-negative nonadherent cell. The biosynthesis and expression of Ia were not increased by direct exposure of macrophages to LPS in vitro. Small amounts of LPS inhibited Ia induction by gamma interferon. LPS showed positive regulatory effects on Ia expression by delaying the loss of Ia expression on cultured macrophages and by stimulating the production of Ia-inducing factors. Supernatants from cultured spleen cells stimulated with LPS in vitro contained antiviral and Ia-inducing activity that was acid labile, indicating that the active factor is gamma interferon. We conclude that induction of Ia expression by LPS in vivo is a bone-marrow-dependent, radiation-sensitive process which involves the stimulation of a gamma interferon-producing accessory lymphocyte and a delay in Ia turnover

Volcanic ash activates the NLRP3 inflammasome in murine and human macrophages

Science.gov (United States)

Damby, David; Horwell, Claire J.; Baxter, Peter J.; Kueppers, Ulrich; Schnurr, Max; Dingwell, Donald B.; Duewell, Peter

2018-01-01

Volcanic ash is a heterogeneous mineral dust that is typically composed of a mixture of amorphous (glass) and crystalline (mineral) fragments. It commonly contains an abundance of the crystalline silica (SiO2) polymorph cristobalite. Inhalation of crystalline silica can induce inflammation by stimulating the NLRP3 inflammasome, a cytosolic receptor complex that plays a critical role in driving inflammatory immune responses. Ingested material results in the assembly of NLRP3, ASC, and caspase-1 with subsequent secretion of the interleukin-1 family cytokine IL-1β. Previous toxicology work suggests that cristobalite-bearing volcanic ash is minimally reactive, calling into question the reactivity of volcanically derived crystalline silica, in general. In this study, we target the NLRP3 inflammasome as a crystalline silica responsive element to clarify volcanic cristobalite reactivity. We expose immortalized bone marrow-derived macrophages of genetically engineered mice and primary human peripheral blood mononuclear cells (PBMCs) to ash from the Soufrière Hills volcano as well as representative, pure-phase samples of its primary componentry (volcanic glass, feldspar, cristobalite) and measure NLRP3 inflammasome activation. We demonstrate that respirable Soufrière Hills volcanic ash induces the activation of caspase-1 with subsequent release of mature IL-1β in a NLRP3 inflammasome-dependent manner. Macrophages deficient in NLRP3 inflammasome components are incapable of secreting IL-1β in response to volcanic ash ingestion. Cellular uptake induces lysosomal destabilization involving cysteine proteases. Furthermore, the response involves activation of mitochondrial stress pathways leading to the generation of reactive oxygen species. Considering ash componentry, cristobalite is the most reactive pure-phase with other components inducing only low-level IL-1β secretion. Inflammasome activation mediated by inhaled ash and its potential relevance in chronic pulmonary

L-Plastin promotes podosome longevity and supports macrophage motility

Science.gov (United States)

Zhou, Julie Y.; Szasz, Taylor P.; Stewart-Hutchinson, Phillip J.; Sivapalan, Janardan; Todd, Elizabeth M.; Deady, Lauren E.; Cooper, John A.; Onken, Michael D.; Morley, S. Celeste

2016-01-01

Elucidating the molecular regulation of macrophage migration is essential for understanding the patho-physiology of multiple human diseases, including host responses to infection and autoimmune disorders. Macrophage migration is supported by dynamic rearrangements of the actin cytoskeleton, with formation of actin-based structures such as podosomes and lamellipodia. Here we provide novel insights into the function of the actin-bundling protein l-plastin (LPL) in primary macrophages. We found that podosome stability is disrupted in primary resident peritoneal macrophages from LPL−/− mice. Live-cell imaging of F-actin using resident peritoneal macrophages from LifeACT-RFP+ mice demonstrated that loss of LPL led to decreased longevity of podosomes, without reducing the number of podosomes initiated. Additionally, macrophages from LPL−/− mice failed to elongate in response to chemotactic stimulation. These deficiencies in podosome stabilization and in macrophage elongation correlated with impaired macrophage transmigration in culture and decreased monocyte migration into murine peritoneum. Thus, we have identified a role for LPL in stabilizing long-lived podosomes and in enabling macrophage motility. PMID:27614263

Peracetylated hydroxytyrosol, a new hydroxytyrosol derivate, attenuates LPS-induced inflammatory response in murine peritoneal macrophages via regulation of non-canonical inflammasome, Nrf2/HO1 and JAK/STAT signaling pathways.

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Montoya, Tatiana; Aparicio-Soto, Marina; Castejón, María Luisa; Rosillo, María Ángeles; Sánchez-Hidalgo, Marina; Begines, Paloma; Fernández-Bolaños, José G; Alarcón-de-la-Lastra, Catalina

2018-03-18

The present study was designed to investigate the anti-inflammatory effects of a new derivative of hydroxytyrosol (HTy), peracetylated hydroxytyrosol (Per-HTy), compared with its parent, HTy, on lipopolysaccharide (LPS)-stimulated murine macrophages as well as potential signaling pathways involved. In particular, we attempted to characterize the role of the inflammasome underlying Per-HTy possible anti-inflammatory effects. Isolated murine peritoneal macrophages were treated with HTy or its derivative in the presence or absence of LPS (5 μg/ml) for 18 h. Cell viability was determined using sulforhodamine B (SRB) assay. Nitric oxide (NO) production was analyzed by Griess method. Production of pro-inflammatory cytokines was evaluated by enzyme-linked immunosorbent assay (ELISA) and inducible nitric oxide synthase (iNOS) and cyclooxygenase (COX)-2, janus kinase/signal transducer and activator of transcription (JAK/STAT) pathway (STAT3), haem oxigenase 1 (HO1), nuclear factor (erythroid-derived 2)-like 2 (Nrf2) expression and mitogen-activated protein kinases (MAPKs) activation was determined by Western blot. Per-HTy significantly reduced the levels of NO and pro-inflammatory cytokines as well as both COX-2 and iNOS expressions. Furthermore, Per-HTy treatment inhibited STAT3 and increased Nrf2 and HO1 protein levels in murine macrophages exposed to LPS. In addition, Per-HTy anti-inflammatory activity was related with an inhibition of non-canonical nucleotide binding domain (NOD)-like receptor (NLRP3) inflammasome pathways by decreasing pro-inflammatory interleukin (IL)-1β and IL-18 cytokine levels as consequence of regulation of cleaved caspase-11 enzyme. These results support that this new HTy derivative may offer a new promising nutraceutical therapeutic strategy in the management of inflammatory-related pathologies. Copyright © 2018. Published by Elsevier Inc.

The role of TREM-2 in internalization and intracellular survival of Brucella abortus in murine macrophages.

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Wei, Pan; Lu, Qiang; Cui, Guimei; Guan, Zhenhong; Yang, Li; Sun, Changjiang; Sun, Wanchun; Peng, Qisheng

2015-02-15

Triggering receptor expressed on myeloid cells-2 (TREM-2) is a cell surface receptor primarily expressed on macrophages and dendritic cells. TREM-2 functions as a phagocytic receptor for bacteria as well as an inhibitor of Toll like receptors (TLR) induced inflammatory cytokines. However, the role of TREM-2 in Brucella intracellular growth remains unknown. To investigate whether TREM-2 is involved in Brucella intracellular survival, we chose bone marrow derived macrophages (BMDMs), in which TREM-2 is stably expressed, as cell model. Colony formation Units (CFUs) assay suggests that TREM-2 is involved in the internalization of Brucella abortus (B. abortus) by macrophages, while silencing of TREM-2 decreases intracellular survival of B. abortus. To further study the underlying mechanisms of TREM-2-mediated bacterial intracellular survival, we examined the activation of B. abortus-infected macrophages through determining the kinetics of activation of the three MAPKs, including ERK, JNK and p38, and measuring TNFα production in response to lipopolysaccharide (LPS) of Brucella (BrLPS) or B. abortus stimulation. Our data show that TREM-2 deficiency promotes activation of Brucella-infected macrophages. Moreover, our data also demonstrate that macrophage activation promotes killing of Brucella by enhancing nitric oxygen (NO), but not reactive oxygen species (ROS) production, macrophage apoptosis or cellular death. Taken together, these findings provide a novel interpretation of Brucella intracellular growth through inhibition of NO production produced by TREM-2-mediated activated macrophages. Copyright © 2014 Elsevier B.V. All rights reserved.

Adipose Type One Innate Lymphoid Cells Regulate Macrophage Homeostasis through Targeted Cytotoxicity.

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Boulenouar, Selma; Michelet, Xavier; Duquette, Danielle; Alvarez, David; Hogan, Andrew E; Dold, Christina; O'Connor, Donal; Stutte, Suzanne; Tavakkoli, Ali; Winters, Desmond; Exley, Mark A; O'Shea, Donal; Brenner, Michael B; von Andrian, Ulrich; Lynch, Lydia

2017-02-21

Adipose tissue has a dynamic immune system that adapts to changes in diet and maintains homeostatic tissue remodeling. Adipose type 1 innate lymphoid cells (AT1-ILCs) promote pro-inflammatory macrophages in obesity, but little is known about their functions at steady state. Here we found that human and murine adipose tissue harbor heterogeneous populations of AT1-ILCs. Experiments using parabiotic mice fed a high-fat diet (HFD) showed differential trafficking of AT1-ILCs, particularly in response to short- and long-term HFD and diet restriction. At steady state, AT1-ILCs displayed cytotoxic activity toward adipose tissue macrophages (ATMs). Depletion of AT1-ILCs and perforin deficiency resulted in alterations in the ratio of inflammatory to anti-inflammatory ATMs, and adoptive transfer of AT1-ILCs exacerbated metabolic disorder. Diet-induced obesity impaired AT1-ILC killing ability. Our findings reveal a role for AT1-ILCs in regulating ATM homeostasis through cytotoxicity and suggest that this function is relevant in both homeostasis and metabolic disease. Copyright © 2017 Elsevier Inc. All rights reserved.

Isolation of human monocytes by double gradient centrifugation and their differentiation to macrophages in teflon-coated cell culture bags.

Science.gov (United States)

Menck, Kerstin; Behme, Daniel; Pantke, Mathias; Reiling, Norbert; Binder, Claudia; Pukrop, Tobias; Klemm, Florian

2014-09-09

Human macrophages are involved in a plethora of pathologic processes ranging from infectious diseases to cancer. Thus they pose a valuable tool to understand the underlying mechanisms of these diseases. We therefore present a straightforward protocol for the isolation of human monocytes from buffy coats, followed by a differentiation procedure which results in high macrophage yields. The technique relies mostly on commonly available lab equipment and thus provides a cost and time effective way to obtain large quantities of human macrophages. Briefly, buffy coats from healthy blood donors are subjected to a double density gradient centrifugation to harvest monocytes from the peripheral blood. These monocytes are then cultured in fluorinated ethylene propylene (FEP) Teflon-coated cell culture bags in the presence of macrophage colony-stimulating factor (M-CSF). The differentiated macrophages can be easily harvested and used for subsequent studies and functional assays. Important methods for quality control and validation of the isolation and differentiation steps will be highlighted within the protocol. In summary, the protocol described here enables scientists to routinely and reproducibly isolate human macrophages without the need for cost intensive tools. Furthermore, disease models can be studied in a syngeneic human system circumventing the use of murine macrophages.

Trastuzumab triggers phagocytic killing of high HER2 cancer cells in vitro and in vivo by interaction with Fcγ receptors on macrophages.

Science.gov (United States)

Shi, Yun; Fan, Xuejun; Deng, Hui; Brezski, Randall J; Rycyzyn, Michael; Jordan, Robert E; Strohl, William R; Zou, Quanming; Zhang, Ningyan; An, Zhiqiang

2015-05-01

Trastuzumab has been used for the treatment of HER2-overexpressing breast cancer for more than a decade, but the mechanisms of action for the therapy are still being actively investigated. Ab-dependent cell-mediated cytotoxicity mediated by NK cells is well recognized as one of the key mechanisms of action for trastuzumab, but trastuzumab-mediated Ab-dependent cellular phagocytosis (ADCP) has not been established. In this study, we demonstrate that macrophages, by way of phagocytic engulfment, can mediate ADCP and cancer cell killing in the presence of trastuzumab. Increased infiltration of macrophages in the tumor tissue was associated with enhanced efficacy of trastuzumab whereas depletion of macrophages resulted in reduced antitumor efficacy in mouse xenograft tumor models. Among the four mouse FcγRs, FcγRIV exhibits the strongest binding affinity to trastuzumab. Knockdown of FcγRIV in mouse macrophages reduced cancer cell killing and ADCP activity triggered by trastuzumab. Consistently, an upregulation of FcγRIV expression by IFN-γ triggered an increased ADCP activity by trastuzumab. In an analogous fashion, IFN-γ priming of human macrophages increased the expression of FcγRIII, the ortholog of murine FcγRIV, and increased trastuzumab-mediated cancer cell killing. Thus, in two independent systems, the results indicated that activation of macrophages in combination with trastuzumab can serve as a therapeutic strategy for treating high HER2 breast cancer by boosting ADCP killing of cancer cells. Copyright © 2015 by The American Association of Immunologists, Inc.

A new and efficient culture method for porcine bone marrow-derived M1- and M2-polarized macrophages.

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Gao, Jiye; Scheenstra, Maaike R; van Dijk, Albert; Veldhuizen, Edwin J A; Haagsman, Henk P

2018-06-01

Macrophages play an important role in the innate immune system as part of the mononuclear phagocyte system (MPS). They have a pro-inflammatory signature (M1-polarized macrophages) or anti-inflammatory signature (M2-polarized macrophages) based on expression of surface receptors and secretion of cytokines. However, very little is known about the culture of macrophages from pigs and more specific about the M1 and M2 polarization in vitro. Porcine monocytes or mononuclear bone marrow cells were used to culture M1- and M2-polarized macrophages in the presence of GM-CSF and M-CSF, respectively. Surface receptor expression was measured with flow cytometry and ELISA was used to quantify cytokine secretion in response to LPS and PAM 3 CSK 4 stimulation. Human monocyte-derived macrophages were used as control. Porcine M1- and M2-polarized macrophages were cultured best using porcine GM-CSF and murine M-CSF, respectively. Cultures from bone marrow cells resulted in a higher yield M1- and M2-polarized macrophages which were better comparable to human monocyte-derived macrophages than cultures from porcine monocytes. Porcine M1-polarized macrophages displayed the characteristic fried egg shape morphology, lower CD163 expression and low IL-10 production. Porcine M2-polarized macrophages contained the spindle-like morphology, higher CD163 expression and high IL-10 production. Porcine M1- and M2-polarized macrophages can be most efficiently cultured from mononuclear bone marrow cells using porcine GM-CSF and murine M-CSF. The new culture method facilitates more refined studies of porcine macrophages in vitro, important for both porcine and human health since pigs are increasingly used as model for translational research. Copyright © 2018 The Authors. Published by Elsevier B.V. All rights reserved.

NMR-based metabonomic analyses of the effects of ultrasmall superparamagnetic particles of iron oxide (USPIO) on macrophage metabolism

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Feng, Jianghua; Zhao, Jing; Hao, Fuhua; Chen, Chang; Bhakoo, Kishore; Tang, Huiru

2011-05-01

The metabonomic changes in murine RAW264.7 macrophage-like cell line induced by ultrasmall superparamagnetic particles of iron oxides (USPIO) have been investigated, by analyzing both the cells and culture media, using high-resolution NMR in conjunction with multivariate statistical methods. Upon treatment with USPIO, macrophage cells showed a significant decrease in the levels of triglycerides, essential amino acids such as valine, isoleucine, and choline metabolites together with an increase of glycerophospholipids, tyrosine, phenylalanine, lysine, glycine, and glutamate. Such cellular responses to USPIO were also detectable in compositional changes of cell media, showing an obvious depletion of the primary nutrition molecules, such as glucose and amino acids and the production of end-products of glycolysis, such as pyruvate, acetate, and lactate and intermediates of TCA cycle such as succinate and citrate. At 48 h treatment, there was a differential response to incubation with USPIO in both cell metabonome and medium components, indicating that USPIO are phagocytosed and released by macrophages. Furthermore, information on cell membrane modification can be derived from the changes in choline-like metabolites. These results not only suggest that NMR-based metabonomic methods have sufficient sensitivity to identify the metabolic consequences of murine RAW264.7 macrophage-like cell line response to USPIO in vitro, but also provide useful information on the effects of USPIO on cellular metabolism.

NMR-based metabonomic analyses of the effects of ultrasmall superparamagnetic particles of iron oxide (USPIO) on macrophage metabolism

International Nuclear Information System (INIS)

Feng Jianghua; Zhao Jing; Hao Fuhua; Chen Chang; Bhakoo, Kishore; Tang, Huiru

2011-01-01

The metabonomic changes in murine RAW264.7 macrophage-like cell line induced by ultrasmall superparamagnetic particles of iron oxides (USPIO) have been investigated, by analyzing both the cells and culture media, using high-resolution NMR in conjunction with multivariate statistical methods. Upon treatment with USPIO, macrophage cells showed a significant decrease in the levels of triglycerides, essential amino acids such as valine, isoleucine, and choline metabolites together with an increase of glycerophospholipids, tyrosine, phenylalanine, lysine, glycine, and glutamate. Such cellular responses to USPIO were also detectable in compositional changes of cell media, showing an obvious depletion of the primary nutrition molecules, such as glucose and amino acids and the production of end-products of glycolysis, such as pyruvate, acetate, and lactate and intermediates of TCA cycle such as succinate and citrate. At 48 h treatment, there was a differential response to incubation with USPIO in both cell metabonome and medium components, indicating that USPIO are phagocytosed and released by macrophages. Furthermore, information on cell membrane modification can be derived from the changes in choline-like metabolites. These results not only suggest that NMR-based metabonomic methods have sufficient sensitivity to identify the metabolic consequences of murine RAW264.7 macrophage-like cell line response to USPIO in vitro, but also provide useful information on the effects of USPIO on cellular metabolism.

Murine iPSC-Derived Macrophages as a Tool for Disease Modeling of Hereditary Pulmonary Alveolar Proteinosis due to Csf2rb Deficiency

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Adele Mucci

2016-08-01

Full Text Available Induced pluripotent stem cells (iPSCs represent an innovative source for the standardized in vitro generation of macrophages (Mφ. We here describe a robust and efficient protocol to obtain mature and functional Mφ from healthy as well as disease-specific murine iPSCs. With regard to morphology, surface phenotype, and function, our iPSC-derived Mφ (iPSC-Mφ closely resemble their counterparts generated in vitro from bone marrow cells. Moreover, when we investigated the feasibility of our differentiation system to serve as a model for rare congenital diseases associated with Mφ malfunction, we were able to faithfully recapitulate the pathognomonic defects in GM-CSF signaling and Mφ function present in hereditary pulmonary alveolar proteinosis (herPAP. Thus, our studies may help to overcome the limitations placed on research into certain rare disease entities by the lack of an adequate supply of disease-specific primary cells, and may aid the development of novel therapeutic approaches for herPAP patients.

Effect of Depleting Tumor-Associated Macrophages on Breast Cancer Growth and Response to Chemotherapy

National Research Council Canada - National Science Library

Tsan, Min-Fu; Gao, Baochong

2005-01-01

.... and whether depletion of tumor-associated macrophages has any effect on the tumor growth. The breast cancer model was established in BALB/c mice by subcutaneous injection of estrogen receptor-positive murine mammary tumor cells (4T1...

Extracellular traps are associated with human and mouse neutrophil and macrophage mediated killing of larval Strongyloides stercoralis.

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Bonne-Année, Sandra; Kerepesi, Laura A; Hess, Jessica A; Wesolowski, Jordan; Paumet, Fabienne; Lok, James B; Nolan, Thomas J; Abraham, David

2014-06-01

Neutrophils are multifaceted cells that are often the immune system's first line of defense. Human and murine cells release extracellular DNA traps (ETs) in response to several pathogens and diseases. Neutrophil extracellular trap (NET) formation is crucial to trapping and killing extracellular pathogens. Aside from neutrophils, macrophages and eosinophils also release ETs. We hypothesized that ETs serve as a mechanism of ensnaring the large and highly motile helminth parasite Strongyloides stercoralis thereby providing a static target for the immune response. We demonstrated that S. stercoralis larvae trigger the release of ETs by human neutrophils and macrophages. Analysis of NETs revealed that NETs trapped but did not kill larvae. Induction of NETs was essential for larval killing by human but not murine neutrophils and macrophages in vitro. In mice, extracellular traps were induced following infection with S. stercoralis larvae and were present in the microenvironment of worms being killed in vivo. These findings demonstrate that NETs ensnare the parasite facilitating larval killing by cells of the immune system. Copyright © 2014 Institut Pasteur. Published by Elsevier Masson SAS. All rights reserved.

DHA suppresses Prevotella intermedia lipopolysaccharide-induced production of proinflammatory mediators in murine macrophages.

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Choi, Eun-Young; Jin, Ji-Young; Choi, Jeom-Il; Choi, In Soon; Kim, Sung-Jo

2014-04-14

Several reports have indicated that dietary intake of DHA is associated with lower prevalence of periodontitis. In the present study, we investigated the effect of DHA on the production of proinflammatory mediators in murine macrophage-like RAW264.7 cells stimulated with lipopolysaccharide (LPS) isolated from Prevotella intermedia, a pathogen implicated in inflammatory periodontal disease, and its mechanisms of action. LPS was isolated from lyophilised P. intermedia ATCC 25,611 cells using the standard hot-phenol-water protocol. Culture supernatants were collected and assayed for NO, IL-1β and IL-6. Real-time PCR analysis was carried out to detect the expression of inducible NO synthase (iNOS), IL-1β, IL-6 and haeme oxygenase-1 (HO-1) mRNA. Immunoblot analysis was carried out to quantify the expression of iNOS and HO-1 protein and concentrations of signalling proteins. DNA-binding activities of NF-κB subunits were determined using an ELISA-based assay kit. DHA significantly attenuated the production of NO, IL-1β and IL-6 at both gene transcription and translation levels in P. intermedia LPS-activated RAW264.7 cells. DHA induced the expression of HO-1 in cells treated with P. intermedia LPS. Selective inhibition of HO-1 activity by tin protoporphyrin IX significantly mitigated the inhibitory effects of DHA on LPS-induced NO production. DHA significantly attenuated the phosphorylation of c-Jun N-terminal kinase induced by LPS. In addition, DHA suppressed the transcriptional activity of NF-κB by regulating the nuclear translocation and DNA-binding activity of NF-κB p50 subunit and inhibited the phosphorylation of signal transducer and activator of transcription 1. Further in vivo studies are needed to better evaluate the potential of DHA in humans as a therapeutic agent to treat periodontal disease.

Murine macrophage response from peritoneal cavity requires signals mediated by chemokine receptor CCR-2 during Staphylococcus aureus infection.

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Nandi, Ajeya; Bishayi, Biswadev

2016-02-01

C-C chemokine receptor-2 (CCR-2) is a cognate receptor for monocyte chemotactic protein-1 (MCP-1), and recent studies revealed that MCP-1-CCR-2 signaling is involved in several inflammatory diseases characterized by macrophage infiltration. Currently, there is no study on the involvement of CCR-2 in the killing of S. aureus by macrophages of Swiss albino mice, and its substantial role in host defense against S. aureus infection in murine macrophages is still unclear. Therefore, the present study was aimed to investigate the functional and interactive role of CCR-2 and MCP-1 in regulating peritoneal macrophage responses with respect to acute S. aureus infection. We found that phagocytosis of S. aureus can serve as an important stimulus for MCP-1 production by peritoneal macrophages, which is dependent directly or indirectly on cytokines, reactive oxygen species and nitric oxide. Neutralization of CCR-2 in macrophages leads to increased production of IL-10 and decreased production of IFN-γ and IL-6. In CCR-2 blocked macrophages, pretreatment with specific blocker of NF-κB or p38-MAPK causes elevation in MCP-1 level and subsequent downregulation of CCR-2 itself. We speculate that CCR-2 is involved in S. aureus-induced MCP-1 production via NF-κB or p38-MAPK signaling. We also hypothesized that unnaturally high level of MCP-1 that build up upon CCR-2 neutralization might allow promiscuous binding to one or more other chemokine receptors, a situation that would not occur in CCR-2 non-neutralized condition. This may be the plausible explanation for such observed Th-2 response in CCR-2 blocked macrophages infected with S. aureus in the present study.

Radiation Therapy Induces Macrophages to Suppress T-Cell Responses Against Pancreatic Tumors in Mice.

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Seifert, Lena; Werba, Gregor; Tiwari, Shaun; Giao Ly, Nancy Ngoc; Nguy, Susanna; Alothman, Sara; Alqunaibit, Dalia; Avanzi, Antonina; Daley, Donnele; Barilla, Rocky; Tippens, Daniel; Torres-Hernandez, Alejandro; Hundeyin, Mautin; Mani, Vishnu R; Hajdu, Cristina; Pellicciotta, Ilenia; Oh, Philmo; Du, Kevin; Miller, George

2016-06-01

The role of radiation therapy in the treatment of patients with pancreatic ductal adenocarcinoma (PDA) is controversial. Randomized controlled trials investigating the efficacy of radiation therapy in patients with locally advanced unresectable PDA have reported mixed results, with effects ranging from modest benefit to worse outcomes compared with control therapies. We investigated whether radiation causes inflammatory cells to acquire an immune-suppressive phenotype that limits the therapeutic effects of radiation on invasive PDAs and accelerates progression of preinvasive foci. We investigated the effects of radiation therapy in p48(Cre);LSL-Kras(G12D) (KC) and p48(Cre);LSLKras(G12D);LSL-Trp53(R172H) (KPC) mice, as well as in C57BL/6 mice with orthotopic tumors grown from FC1242 cells derived from KPC mice. Some mice were given neutralizing antibodies against macrophage colony-stimulating factor 1 (CSF1 or MCSF) or F4/80. Pancreata were exposed to doses of radiation ranging from 2 to 12 Gy and analyzed by flow cytometry. Pancreata of KC mice exposed to radiation had a higher frequency of advanced pancreatic intraepithelial lesions and more foci of invasive cancer than pancreata of unexposed mice (controls); radiation reduced survival time by more than 6 months. A greater proportion of macrophages from radiation treated invasive and preinvasive pancreatic tumors had an immune-suppressive, M2-like phenotype compared with control mice. Pancreata from mice exposed to radiation had fewer CD8(+) T cells than controls, and greater numbers of CD4(+) T cells of T-helper 2 and T-regulatory cell phenotypes. Adoptive transfer of T cells from irradiated PDA to tumors of control mice accelerated tumor growth. Radiation induced production of MCSF by PDA cells. A neutralizing antibody against MCSF prevented radiation from altering the phenotype of macrophages in tumors, increasing the anti-tumor T-cell response and slowing tumor growth. Radiation treatment causes macrophages

Polyelectrolyte Complex Optimization for Macrophage Delivery of Redox Enzyme Nanoparticles

Science.gov (United States)

Zhao, Yuling; Haney, Matthew J.; Klyachko, Natalia L.; Li, Shu; Booth, Stephanie L.; Higginbotham, Sheila M.; Jones, Jocelyn; Zimmerman, Matthew C.; Mosley, R. Lee; Kabanov, Alexander V.; Gendelman, Howard E.; Batrakova, Elena V.

2011-01-01

Background We posit that cell-mediated drug delivery can improve transport of therapeutic enzymes to the brain and decrease inflammation and neurodegeneration induced during Parkinson’s disease. Our prior work demonstrated that macrophages loaded with nanoformulated catalase (“nanozyme”) protect the nigrostriatum in a murine model of Parkinson’s disease. Packaging of catalase into block ionomer complex with a synthetic polyelectrolyte block copolymers protects the enzyme degradation in macrophages. Methods We examined relationships between the composition and structure of block ionomer complexes, their physicochemical characteristics, and loadings, release rates, and catalase activity in bone marrow-derived macrophages. Results Formation of block-ionomer complexes resulted in improved aggregation stability. Block ionomer complexes with ε-polylisine, and poly-L-glutamic acid -poly(ethylene glycol) demonstrated the least cytotoxicity and high loading and release rates, however, did not efficiently protect catalase inside macrophages. Conclusion nanozymes with polyethyleneimine- and poly(L-lysine)10-poly(ethylene glycol) provided the best protection of enzymatic activity for cell-mediated drug delivery. PMID:21182416

Semaphorin7A promotes tumor growth and exerts a pro-angiogenic effect in macrophages of mammary tumor-bearing mice

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Ramon eGarcia-Areas

2014-02-01

Full Text Available Semaphorins, a large family of molecules involved in the axonal guidance and development of the nervous system, have been recently shown to have both angiogenic and anti-angiogenic properties. Specifically, semaphorin 7A (SEMA7A has been reported to have a chemotactic activity in neurogenesis, and to be an immune modulator via it binding to α1β1integrins. Additionally, SEMA7A has been shown to promote chemotaxis of monocytes, inducing them to produce proinflammatory mediators. In this study we explored the role of SEMA7A in the tumoral context. We show that SEMA7A is highly expressed by DA-3 murine mammary tumor cells in comparison to normal mammary cells (EpH4, and that peritoneal macrophages from mammary tumor-bearing mice also express SEMA7A at higher levels compared to peritoneal macrophages derived from normal control mice. We also show that murine macrophages treated with recombinant murine SEMA7A significantly increased their expression of proangiogenic molecules, such as CXCL2/MIP-2. Gene silencing of SEMA7A in peritoneal elicited macrophages from DA-3 tumor-bearing mice resulted in decreased CXCL2 expression. Mice implanted with SEMA7A silenced tumor cells showed decreased angiogenesis in the tumors compared to the wild type tumors. Furthermore, peritoneal elicited macrophages from mice bearing SEMA7A-silenced tumors produce significantly (p< 0.01 lower levels of angiogenic proteins, such as MIP-2, CXCL1 and MMP-9, compared to macrophages from control DA-3 mammary tumors. We postulate that SEMA7A derived from mammary carcinomas may serve as a monocyte chemoattractant and skew monocytes into a pro-tumorigenic phenotype. A putative relationship between tumor-derived SEMA7A and monocytes could prove valuable in establishing new research avenues towards unraveling important tumor-host immune interactions in breast cancer patients.

Ginger extract inhibits LPS induced macrophage activation and function

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Bruch David

2008-01-01

Full Text Available Abstract Background Macrophages play a dual role in host defence. They act as the first line of defence by mounting an inflammatory response to antigen exposure and also act as antigen presenting cells and initiate the adaptive immune response. They are also the primary infiltrating cells at the site of inflammation. Inhibition of macrophage activation is one of the possible approaches towards modulating inflammation. Both conventional and alternative approaches are being studied in this regard. Ginger, an herbal product with broad anti inflammatory actions, is used as an alternative medicine in a number of inflammatory conditions like rheumatic disorders. In the present study we examined the effect of ginger extract on macrophage activation in the presence of LPS stimulation. Methods Murine peritoneal macrophages were stimulated by LPS in presence or absence of ginger extract and production of proinflammatory cytokines and chemokines were observed. We also studied the effect of ginger extract on the LPS induced expression of MHC II, B7.1, B7.2 and CD40 molecules. We also studied the antigen presenting function of ginger extract treated macrophages by primary mixed lymphocyte reaction. Results We observed that ginger extract inhibited IL-12, TNF-α, IL-1β (pro inflammatory cytokines and RANTES, MCP-1 (pro inflammatory chemokines production in LPS stimulated macrophages. Ginger extract also down regulated the expression of B7.1, B7.2 and MHC class II molecules. In addition ginger extract negatively affected the antigen presenting function of macrophages and we observed a significant reduction in T cell proliferation in response to allostimulation, when ginger extract treated macrophages were used as APCs. A significant decrease in IFN-γ and IL-2 production by T cells in response to allostimulation was also observed. Conclusion In conclusion ginger extract inhibits macrophage activation and APC function and indirectly inhibits T cell activation.

Tracking bacterial infection of macrophages using a novel red-emission pH sensor.

Science.gov (United States)

Jin, Yuguang; Tian, Yanqing; Zhang, Weiwen; Jang, Sei-Hum; Jen, Alex K-Y; Meldrum, Deirdre R

2010-10-01

The relationship between bacteria and host phagocytic cells is key to the induction of immunity. To visualize and monitor bacterial infection, we developed a novel bacterial membrane permeable pH sensor for the noninvasive monitoring of bacterial entry into murine macrophages. The pH sensor was constructed using 2-dicyanomethylene-3-cyano-4,5,5-trimethyl-2,5-dihydrofuran (TCF) as an electron-withdrawing group and aniline as an electron-donating group. A piperazine moiety was used as the pH-sensitive group. Because of the strong electron-donating and -withdrawing units conjugated in the sensing moiety M, the fluorophore emitted in the red spectral window, away from the autofluorescence regions of the bacteria. Following the engulfment of sensor-labeled bacteria by macrophages and their subsequent merger with host lysosomes, the resulting low-pH environment enhances the fluorescence intensity of the pH sensors inside the bacteria. Time-lapse analysis of the fluorescent intensity suggested significant heterogeneity of bacterial uptake among macrophages. In addition, qRT-PCR analysis of the bacterial 16 S rRNA gene expression within single macrophage cells suggested that the 16 S rRNA of the bacteria was still intact 120 min after they had been engulfed by macrophages. A toxicity assay showed that the pH sensor has no cytotoxicity towards either E. coli or murine macrophages. The sensor shows good repeatability, a long lifetime, and a fast response to pH changes, and can be used for a variety of bacteria.

Roles of Chaperone/Usher Pathways of Yersinia pestis in a Murine Model of Plague and Adhesion to Host Cells

Science.gov (United States)

Hatkoff, Matthew; Runco, Lisa M.; Pujol, Celine; Jayatilaka, Indralatha; Furie, Martha B.; Bliska, James B.

2012-01-01

Yersinia pestis and many other Gram-negative pathogenic bacteria use the chaperone/usher (CU) pathway to assemble virulence-associated surface fibers termed pili or fimbriae. Y. pestis has two well-characterized CU pathways: the caf genes coding for the F1 capsule and the psa genes coding for the pH 6 antigen. The Y. pestis genome contains additional CU pathways that are capable of assembling pilus fibers, but the roles of these pathways in the pathogenesis of plague are not understood. We constructed deletion mutations in the usher genes for six of the additional Y. pestis CU pathways. The wild-type (WT) and usher deletion strains were compared in the murine bubonic (subcutaneous) and pneumonic (intranasal) plague infection models. Y. pestis strains containing deletions in CU pathways y0348-0352, y1858-1862, and y1869-1873 were attenuated for virulence compared to the WT strain by the intranasal, but not subcutaneous, routes of infection, suggesting specific roles for these pathways during pneumonic plague. We examined binding of the Y. pestis WT and usher deletion strains to A549 human lung epithelial cells, HEp-2 human cervical epithelial cells, and primary human and murine macrophages. Y. pestis CU pathways y0348-0352 and y1858-1862 were found to contribute to adhesion to all host cells tested, whereas pathway y1869-1873 was specific for binding to macrophages. The correlation between the virulence attenuation and host cell binding phenotypes of the usher deletion mutants identifies three of the additional CU pathways of Y. pestis as mediating interactions with host cells that are important for the pathogenesis of plague. PMID:22851745

Rhizoma coptidis Inhibits LPS-Induced MCP-1/CCL2 Production in Murine Macrophages via an AP-1 and NFB-Dependent Pathway

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Andrew Remppis

2010-01-01

Full Text Available Introduction. The Chinese extract Rhizoma coptidis is well known for its anti-inflammatory, antioxidative, antiviral, and antimicrobial activity. The exact mechanisms of action are not fully understood. Methods. We examined the effect of the extract and its main compound, berberine, on LPS-induced inflammatory activity in a murine macrophage cell line. RAW 264.7 cells were stimulated with LPS and incubated with either Rhizoma coptidis extract or berberine. Activation of AP-1 and NFB was analyzed in nuclear extracts, secretion of MCP-1/CCL2 was measured in supernatants. Results. Incubation with Rhizoma coptidis and berberine strongly inhibited LPS-induced monocyte chemoattractant protein (MCP-1 production in RAW cells. Activation of the transcription factors AP-1 and NFB was inhibited by Rhizoma coptidis in a dose- and time-dependent fashion. Conclusions. Rhizoma coptidis extract inhibits LPS-induced MCP-1/CCL2 production in vitro via an AP-1 and NFB-dependent pathway. Anti-inflammatory action of the extract is mediated mainly by its alkaloid compound berberine.

Liver X Receptor (LXR) activation negatively regulates visfatin expression in macrophages

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Mayi, Therese Hervee; Rigamonti, Elena [Univ Lille Nord de France, F-59000 Lille (France); INSERM UR1011, F-59000 Lille (France); UDSL, F-59000 Lille (France); Institut Pasteur de Lille, F-59019 Lille (France); Pattou, Francois [Univ Lille Nord de France, F-59000 Lille (France); Department of Endocrine Surgery, University Hospital, Lille (France); U859 Biotherapies for Diabetes, INSERM, Lille (France); Staels, Bart, E-mail: bart.staels@pasteur-lille.fr [Univ Lille Nord de France, F-59000 Lille (France); INSERM UR1011, F-59000 Lille (France); UDSL, F-59000 Lille (France); Institut Pasteur de Lille, F-59019 Lille (France); Chinetti-Gbaguidi, Giulia [Univ Lille Nord de France, F-59000 Lille (France); INSERM UR1011, F-59000 Lille (France); UDSL, F-59000 Lille (France); Institut Pasteur de Lille, F-59019 Lille (France)

2011-01-07

Research highlights: {yields} Synthetic LXR ligands decreased visfatin expression in human macrophages. {yields} LXR activation leads to a modest and transient decrease of NAD{sup +} concentration. {yields} LXR activation decreased PPAR{gamma}-induced visfatin in human macrophages. -- Abstract: Adipose tissue macrophages (ATM) are the major source of visfatin, a visceral fat adipokine upregulated during obesity. Also known to play a role in B cell differentiation (pre-B cell colony-enhancing factor (PBEF)) and NAD biosynthesis (nicotinamide phosphoribosyl transferase (NAMPT)), visfatin has been suggested to play a role in inflammation. Liver X Receptor (LXR) and Peroxisome Proliferator-Activated Receptor (PPAR){gamma} are nuclear receptors expressed in macrophages controlling the inflammatory response. Recently, we reported visfatin as a PPAR{gamma} target gene in human macrophages. In this study, we examined whether LXR regulates macrophage visfatin expression. Synthetic LXR ligands decreased visfatin gene expression in a LXR-dependent manner in human and murine macrophages. The decrease of visfatin mRNA was paralleled by a decrease of protein secretion. Consequently, a modest and transient decrease of NAD{sup +} concentration was observed. Interestingly, LXR activation decreased the PPAR{gamma}-induced visfatin gene and protein secretion in human macrophages. Our results identify visfatin as a gene oppositely regulated by the LXR and PPAR{gamma} pathways in human macrophages.

An Anacardiaceae preparation reduces the expression of inflammation-related genes in murine macrophages.

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Leiro, J; García, D; Arranz, J A; Delgado, R; Sanmartín, M L; Orallo, F

2004-08-01

This study investigated the effects of an aqueous extract of the stem bark of Mangifera indica L. (Anacardiaceae; Vimang), which contains a defined mixture of components including polyphenols (principally mangiferin, MA), triterpenes, phytosteroids, fatty acids and microelements, on expression of inflammation mediators in inflammatory murine macrophages after stimulation in vitro with lipopolysaccharide (LPS) and interferon-gamma (IFN-gamma). In vitro treatment with Vimang at 4 microg/ml reduced levels of NOS-2 mRNA and NOS-2, while treatment at 40 microg/ml also reduced levels of COX-2 mRNA, COX-2, and prostaglandin E2 (PGE2). Results suggested that MA is involved in these effects. In vitro treatment with Vimang at 40 microg/ml also inhibited mRNA levels of the proinflammatory cytokines interleukin 1beta (IL-1beta), tumor necrosis factor alpha (TNF-alpha) and colony-stimulating factor (GM-CSF), but did not affect mRNA levels of IL-6 or tumor growth factor-beta (TGF-beta). Extracellular release of TNF-alpha by inflammatory macrophages was inhibited by in vitro treatment with Vimang at the same concentrations that showed inhibition of TNF-alpha mRNA levels. The inhibition of TNF-alpha production appears to be at least partially attributable to MA. Vimang at 4 microg/ml decreased mRNA levels of nuclear factor-kappaB (NF-kappaB) but did not affect expression of the NF-kappaB inhibitor (IkappaB). These data indicate that the potent anti-inflammatory effects of Vimang are due to selective modulation of the expression of inflammation-related genes, leading to attenuation of macrophage activation.

Anti-inflammation effect of methyl salicylate 2-O-β-D-lactoside on adjuvant induced-arthritis rats and lipopolysaccharide (LPS)-treated murine macrophages RAW264.7 cells.

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Zhang, Xue; Sun, Jialin; Xin, Wenyu; Li, Yongjie; Ni, Lin; Ma, Xiaowei; Zhang, Dan; Zhang, Dongming; Zhang, Tiantai; Du, Guanhua

2015-03-01

Methyl salicylate 2-O-β-D-lactoside (MSL) is a derivative of natural salicylate isolated from Gaultheria yunnanensis (Franch.) Rehder, which is widely used for treating rheumatoid arthritis (RA), swelling and pain. The aim of the present study was to investigate the effect of MSL on the progression of adjuvant-induced arthritis (AIA) in rat in vivo and explore the anti-inflammatory effects and mechanism of MSL in lipopolysaccharide (LPS)-treated murine macrophages RAW264.7 cells in vitro. Our results showed that MSL significantly inhibited the arthritis progression in AIA rats, decreasing the right hind paw swelling and ankle diameter, attenuating histopathological changes and suppressing the plasma levels of TNF-α and IL-1β in AIA rats. Besides, MSL had potent anti-inflammatory effects on the LPS-activated RAW264.7. MSL dose-dependently inhibited the activity of COX-1, and COX-2. Moreover, MSL prominently inhibited LPS-induced activation of MAPK in RAW264.7 cells by blocking phosphorylation of p38 and ERK. Our study suggests that MSL may be effective in the treatment of inflammatory diseases by inhibiting the pro-inflammatory cytokine production and regulating the MAPK signal pathway. Copyright © 2015. Published by Elsevier B.V.

Triglyceride-induced macrophage cell death is triggered by caspase-1.

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Son, Sin Jee; Rhee, Ki-Jong; Lim, Jaewon; Kim, Tae Ue; Kim, Tack-Joong; Kim, Yoon Suk

2013-01-01

Triglyceride (TG) induces macrophage cell death which contributes to the development of atherosclerosis. We confirmed that exogenous TG accumulates in human THP-1 macrophages and causes cell death. TG treated THP-1 macrophages exhibited no change in tumor necrosis factor (TNF)-α, interleukin (IL)-18, macrophage inflammatory protein (MIP)-1α, and IL-1R1 receptor mRNA expression. However, there was a marked decrease in IL-1β mRNA expression but an increase in IL-1β protein secretion. Decreased expression of IL-1β mRNA and increased secretion of IL-1β protein was not the direct cause of cell death. Until now, TG was assumed to induce necrotic cell death in macrophages. Since caspase-1 is known to be involved in activation and secretion of IL-1β protein and pyroptotic cell death, next we determined whether caspase-1 is associated with TG-induced macrophage cell death. We found an increase in caspase-1 activity in TG-treated THP-1 macrophages and inhibition of caspase-1 activity using a specific inhibitor partially rescued cell death. These results suggest activation of the pyroptotic pathway by TG. This is the first report implicating the activation of caspase-1 and the triggering of the pyroptosis pathway in TG-induced macrophage cell death.

Networked T cell death following macrophage infection by Mycobacterium tuberculosis.

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Stephen H-F Macdonald

Full Text Available BACKGROUND: Depletion of T cells following infection by Mycobacterium tuberculosis (Mtb impairs disease resolution, and interferes with clinical test performance that relies on cell-mediated immunity. A number of mechanisms contribute to this T cell suppression, such as activation-induced death and trafficking of T cells out of the peripheral circulation and into the diseased lungs. The extent to which Mtb infection of human macrophages affects T cell viability however, is not well characterised. METHODOLOGY/PRINCIPAL FINDINGS: We found that lymphopenia (<1.5 × 10(9 cells/l was prevalent among culture-positive tuberculosis patients, and lymphocyte counts significantly improved post-therapy. We previously reported that Mtb-infected human macrophages resulted in death of infected and uninfected bystander macrophages. In the current study, we sought to examine the influence of infected human alveolar macrophages on T cells. We infected primary human alveolar macrophages (the primary host cell for Mtb or PMA-differentiated THP-1 cells with Mtb H37Ra, then prepared cell-free supernatants. The supernatants of Mtb-infected macrophages caused dose-dependent, caspase-dependent, T cell apoptosis. This toxic effect of infected macrophage secreted factors did not require TNF-α or Fas. The supernatant cytotoxic signal(s were heat-labile and greater than 50 kDa in molecular size. Although ESAT-6 was toxic to T cells, other Mtb-secreted factors tested did not influence T cell viability; nor did macrophage-free Mtb bacilli or broth from Mtb cultures. Furthermore, supernatants from Mycobacterium bovis Bacille de Calmette et Guerin (BCG- infected macrophages also elicited T cell death suggesting that ESAT-6 itself, although cytotoxic, was not the principal mediator of T cell death in our system. CONCLUSIONS: Mtb-Infected macrophages secrete heat-labile factors that are toxic to T cells, and may contribute to the immunosuppression seen in tuberculosis as well as

Macrophage polarization in nerve injury: do Schwann cells play a role?

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Jo Anne Stratton

2016-01-01

Full Text Available In response to peripheral nerve injury, the inflammatory response is almost entirely comprised of infiltrating macrophages. Macrophages are a highly plastic, heterogenic immune cell, playing an indispensable role in peripheral nerve injury, clearing debris and regulating the microenvironment to allow for efficient regeneration. There are several cells within the microenvironment that likely interact with macrophages to support their function - most notably the Schwann cell, the glial cell of the peripheral nervous system. Schwann cells express several ligands that are known to interact with receptors expressed by macrophages, yet the effects of Schwann cells in regulating macrophage phenotype remains largely unexplored. This review discusses macrophages in peripheral nerve injury and how Schwann cells may regulate their behavior.

Apoptotic death of Listeria monocytogenes-infected human macrophages induced by lactoferricin B, a bovine lactoferrin-derived peptide.

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Longhi, C; Conte, M P; Ranaldi, S; Penta, M; Valenti, P; Tinari, A; Superti, F; Seganti, L

2005-01-01

Listeria monocytogenes, an intracellular facultative food-borne pathogen, was reported to induce apoptosis in vitro and in vivo in a variety of cell types with the exception of murine macrophages. These cells represent the predominant compartment of bacterial multiplication and die as a result of necrosis. In this study we showed that human non-activated and IFN-gamma-activated macrophagic-like (THP-1) cells infected with L. monocytogenes, mainly die by necrosis rather than by an apoptotic process. Two natural products derived from bovine milk, lactoferrin and its derivative peptide lactoferricin B, are capable of regulating the fate of infected human macrophages. Bovine lactoferrin treatment of macrophages protects them from L. monocytogenes-induced death whereas lactoferricin B, its derivative peptide, determines a shifting of the equilibrium from necrosis to apoptosis.

Characterization of Burkholderia pseudomallei Strains Using a Murine Intraperitoneal Infection Model and In Vitro Macrophage Assays.

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Susan L Welkos

Full Text Available Burkholderia pseudomallei, the etiologic agent of melioidosis, is a gram-negative facultative intracellular bacterium. This bacterium is endemic in Southeast Asia and Northern Australia and can infect humans and animals by several routes. It has also been estimated to present a considerable risk as a potential biothreat agent. There are currently no effective vaccines for B. pseudomallei, and antibiotic treatment can be hampered by nonspecific symptomology, the high incidence of naturally occurring antibiotic resistant strains, and disease chronicity. Accordingly, there is a concerted effort to better characterize B. pseudomallei and its associated disease. Before novel vaccines and therapeutics can be tested in vivo, a well characterized animal model is essential. Previous work has indicated that mice may be a useful animal model. In order to develop standardized animal models of melioidosis, different strains of bacteria must be isolated, propagated, and characterized. Using a murine intraperitoneal (IP infection model, we tested the virulence of 11 B. pseudomallei strains. The IP route offers a reproducible way to rank virulence that can be readily reproduced by other laboratories. This infection route is also useful in distinguishing significant differences in strain virulence that may be masked by the exquisite susceptibility associated with other routes of infection (e.g., inhalational. Additionally, there were several pathologic lesions observed in mice following IP infection. These included varisized abscesses in the spleen, liver, and haired skin. This model indicated that commonly used laboratory strains of B. pseudomallei (i.e., K96243 and 1026b were significantly less virulent as compared to more recently acquired clinical isolates. Additionally, we characterized in vitro strain-associated differences in virulence for macrophages and described a potential inverse relationship between virulence in the IP mouse model of some strains

Characterization of Burkholderia pseudomallei Strains Using a Murine Intraperitoneal Infection Model and In Vitro Macrophage Assays.

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Welkos, Susan L; Klimko, Christopher P; Kern, Steven J; Bearss, Jeremy J; Bozue, Joel A; Bernhards, Robert C; Trevino, Sylvia R; Waag, David M; Amemiya, Kei; Worsham, Patricia L; Cote, Christopher K

2015-01-01

Burkholderia pseudomallei, the etiologic agent of melioidosis, is a gram-negative facultative intracellular bacterium. This bacterium is endemic in Southeast Asia and Northern Australia and can infect humans and animals by several routes. It has also been estimated to present a considerable risk as a potential biothreat agent. There are currently no effective vaccines for B. pseudomallei, and antibiotic treatment can be hampered by nonspecific symptomology, the high incidence of naturally occurring antibiotic resistant strains, and disease chronicity. Accordingly, there is a concerted effort to better characterize B. pseudomallei and its associated disease. Before novel vaccines and therapeutics can be tested in vivo, a well characterized animal model is essential. Previous work has indicated that mice may be a useful animal model. In order to develop standardized animal models of melioidosis, different strains of bacteria must be isolated, propagated, and characterized. Using a murine intraperitoneal (IP) infection model, we tested the virulence of 11 B. pseudomallei strains. The IP route offers a reproducible way to rank virulence that can be readily reproduced by other laboratories. This infection route is also useful in distinguishing significant differences in strain virulence that may be masked by the exquisite susceptibility associated with other routes of infection (e.g., inhalational). Additionally, there were several pathologic lesions observed in mice following IP infection. These included varisized abscesses in the spleen, liver, and haired skin. This model indicated that commonly used laboratory strains of B. pseudomallei (i.e., K96243 and 1026b) were significantly less virulent as compared to more recently acquired clinical isolates. Additionally, we characterized in vitro strain-associated differences in virulence for macrophages and described a potential inverse relationship between virulence in the IP mouse model of some strains and in the

Complement regulation in murine and human hypercholesterolemia and role in the control of macrophage and smooth muscle cell proliferation.

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Verdeguer, Francisco; Castro, Claudia; Kubicek, Markus; Pla, Davinia; Vila-Caballer, Marian; Vinué, Angela; Civeira, Fernando; Pocoví, Miguel; Calvete, Juan José; Andrés, Vicente

2007-11-01

Mounting evidence suggests that activation of complement, an important constituent of innate immunity, contributes to atherosclerosis. Here we investigated the expression of complement components (CCs) in the setting of experimental and clinical hypercholesterolemia, a major risk factor for atherosclerosis, their effects on vascular smooth muscle cell (VSMC) and macrophage proliferation, and the underlying molecular mechanisms. For this study we analyzed the mRNA and protein expression of several CCs in plasma and aorta of hypercholesterolemic atherosclerosis-prone apolipoprotein E-null mice (apoE-KO) and in plasma of normocholesterolemic subjects and familial hypercholesterolemia (FH) patients. We also carried out in vitro molecular studies to assess the role of CCs on the control of macrophage and VSMC proliferation. Fat-fed apoE-KO mice experiencing severe hypercholesterolemia (approximately 400 mg/dL), but not fat-fed wild-type controls with plasma cholesterol levelfeeding when hypercholesterolemia was manifested yet atherosclerotic lesions were absent or incipient. Rapid C3 and C4 protein upregulation was also observed in the plasma of fat-fed apoE-KO mice, and FH patients exhibited higher plasmatic C3a, C4 gamma chain, C1s and C3c alpha chain protein levels than normocholesterolemic subjects. In vitro, C3 and C3a, but not C3a-desArg, C4 and C1q, promoted macrophage and VSMC proliferation through Gi protein-dependent activation of extracellular signal-regulated kinase 1/2 (ERK1/2). We also found that C3-enriched FH plasma evoked a stronger mitogenic response in macrophages than normocholesterolemic plasma, and treatment with anti-C3 antibodies eliminated this difference. Both experimental and clinical hypercholesterolemia coincides with a concerted activation of several CCs. However, only C3 and C3a elicited a mitogenic response in cultured VSMCs and macrophages through Gi protein-dependent ERK1/2 activation. Thus, excess of C3/C3a in hypercholesterolemic apo

Reciprocal interactions between endothelial cells and macrophages in angiogenic vascular niches

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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

Suppression of IL-12p70 formation by IL-2 or following macrophage depletion causes T-cell autoreactivity leading to CNS demyelination in HSV-1-infected mice.

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Dhong Hyun Lee

2017-05-01

Full Text Available We have established two mouse models of central nervous system (CNS demyelination that differ from most other available models of multiple sclerosis (MS in that they represent a mixture of viral and immune triggers. In the first model, ocular infection of different strains of mice with a recombinant HSV-1 that expresses murine IL-2 constitutively (HSV-IL-2 causes CNS demyelination. In the second model, depletion of macrophages causes CNS demyelination in mice that are ocularly infected with wild-type (WT HSV-1. In the present study, we found that the demyelination in macrophage-intact mice infected with HSV-IL-2 was blocked by depletion of FoxP3-expressing cells, while concurrent depletion of macrophages restored demyelination. In contrast, demyelination was blocked in the macrophage-depleted mice infected with wild-type HSV-1 following depletion of FoxP3-expressing cells. In macrophage-depleted HSV-IL-2-infected mice, demyelination was associated with the activity of both CD4+ and CD8+ T cells, whereas in macrophage-depleted mice infected with WT HSV-1, demyelination was associated with CD4+ T cells. Macrophage depletion or infection with HSV-IL-2 caused an imbalance of T cells and TH1 responses as well as alterations in IL-12p35 and IL-12p40 but not other members of the IL-12 family or their receptors. Demyelination was blocked by adoptive transfer of macrophages that were infected with HSV-IL-12p70 or HSV-IL-12p40 but not by HSV-IL-12p35. These results indicate that suppression of IL-12p70 formation by IL-2 or following macrophage depletion causes T-cell autoreactivity leading to CNS demyelination in HSV-1-infected mice.

Cytokine overproduction and crosslinker hypersensitivity are unlinked in Fanconi anemia macrophages.

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Garbati, Michael R; Hays, Laura E; Rathbun, R Keaney; Jillette, Nathaniel; Chin, Kathy; Al-Dhalimy, Muhsen; Agarwal, Anupriya; Newell, Amy E Hanlon; Olson, Susan B; Bagby, Grover C

2016-03-01

The Fanconi anemia proteins participate in a canonical pathway that repairs cross-linking agent-induced DNA damage. Cells with inactivated Fanconi anemia genes are universally hypersensitive to such agents. Fanconi anemia-deficient hematopoietic stem cells are also hypersensitive to inflammatory cytokines, and, as importantly, Fanconi anemia macrophages overproduce such cytokines in response to TLR4 and TLR7/8 agonists. We questioned whether TLR-induced DNA damage is the primary cause of aberrantly regulated cytokine production in Fanconi anemia macrophages by quantifying TLR agonist-induced TNF-α production, DNA strand breaks, crosslinker-induced chromosomal breakage, and Fanconi anemia core complex function in Fanconi anemia complementation group C-deficient human and murine macrophages. Although both M1 and M2 polarized Fanconi anemia cells were predictably hypersensitive to mitomycin C, only M1 macrophages overproduced TNF-α in response to TLR-activating signals. DNA damaging agents alone did not induce TNF-α production in the absence of TLR agonists in wild-type or Fanconi anemia macrophages, and mitomycin C did not enhance TLR responses in either normal or Fanconi anemia cells. TLR4 and TLR7/8 activation induced cytokine overproduction in Fanconi anemia macrophages. Also, although TLR4 activation was associated with induced double strand breaks, TLR7/8 activation was not. That DNA strand breaks and chromosome breaks are neither necessary nor sufficient to account for the overproduction of inflammatory cytokines by Fanconi anemia cells suggests that noncanonical anti-inflammatory functions of Fanconi anemia complementation group C contribute to the aberrant macrophage phenotype and suggests that suppression of macrophage/TLR hyperreactivity might prevent cytokine-induced stem cell attrition in Fanconi anemia. © Society for Leukocyte Biology.

T Cell Zone Resident Macrophages Silently Dispose of Apoptotic Cells in the Lymph Node.

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Baratin, Myriam; Simon, Léa; Jorquera, Audrey; Ghigo, Clément; Dembele, Doulaye; Nowak, Jonathan; Gentek, Rebecca; Wienert, Stephan; Klauschen, Frederick; Malissen, Bernard; Dalod, Marc; Bajénoff, Marc

2017-08-15

In lymph nodes (LNs), dendritic cells (DCs) are thought to dispose of apoptotic cells, a function pertaining to macrophages in other tissues. We found that a population of CX3CR1 + MERTK + cells located in the T cell zone of LNs, previously identified as DCs, are efferocytic macrophages. Lineage-tracing experiments and shield chimeras indicated that these T zone macrophages (TZM) are long-lived macrophages seeded in utero and slowly replaced by blood monocytes after birth. Imaging the LNs of mice in which TZM and DCs express different fluorescent proteins revealed that TZM-and not DCs-act as the only professional scavengers, clearing apoptotic cells in the LN T cell zone in a CX3CR1-dependent manner. Furthermore, similar to other macrophages, TZM appear inefficient in priming CD4 T cells. Thus, efferocytosis and T cell activation in the LN are uncoupled processes designated to macrophages and DCs, respectively, with implications to the maintenance of immune homeostasis. Copyright © 2017 Elsevier Inc. All rights reserved.

Rhizoma Coptidis Inhibits LPS-Induced MCP-1/CCL2 Production in Murine Macrophages via an AP-1 and NFκB-Dependent Pathway

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Remppis, Andrew; Bea, Florian; Greten, Henry Johannes; Buttler, Annette; Wang, Hongjie; Zhou, Qianxing; Preusch, Michael R.; Enk, Ronny; Ehehalt, Robert; Katus, Hugo; Blessing, Erwin

2010-01-01

Introduction. The Chinese extract Rhizoma coptidis is well known for its anti-inflammatory, antioxidative, antiviral, and antimicrobial activity. The exact mechanisms of action are not fully understood. Methods. We examined the effect of the extract and its main compound, berberine, on LPS-induced inflammatory activity in a murine macrophage cell line. RAW 264.7 cells were stimulated with LPS and incubated with either Rhizoma coptidis extract or berberine. Activation of AP-1 and NFκB was analyzed in nuclear extracts, secretion of MCP-1/CCL2 was measured in supernatants. Results. Incubation with Rhizoma coptidis and berberine strongly inhibited LPS-induced monocyte chemoattractant protein (MCP)-1 production in RAW cells. Activation of the transcription factors AP-1 and NFκB was inhibited by Rhizoma coptidis in a dose- and time-dependent fashion. Conclusions. Rhizoma coptidis extract inhibits LPS-induced MCP-1/CCL2 production in vitro via an AP-1 and NFκB-dependent pathway. Anti-inflammatory action of the extract is mediated mainly by its alkaloid compound berberine. PMID:20652055

Phosphoethanolamine Modification of Neisseria gonorrhoeae Lipid A Reduces Autophagy Flux in Macrophages.

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Susu M Zughaier

Full Text Available Autophagy, an ancient homeostasis mechanism for macromolecule degradation, performs an important role in host defense by facilitating pathogen elimination. To counteract this host defense strategy, bacterial pathogens have evolved a variety of mechanisms to avoid or otherwise dysregulate autophagy by phagocytic cells so as to enhance their survival during infection. Neisseria gonorrhoeae is a strictly human pathogen that causes the sexually transmitted infection, gonorrhea. Phosphoethanolamine (PEA addition to the 4' position of the lipid A (PEA-lipid A moiety of the lipooligosaccharide (LOS produced by gonococci performs a critical role in this pathogen's ability to evade innate defenses by conferring decreased susceptibility to cationic antimicrobial (or host-defense peptides, complement-mediated killing by human serum and intraleukocytic killing by human neutrophils compared to strains lacking this PEA decoration. Heretofore, however, it was not known if gonococci can evade autophagy and if so, whether PEA-lipid A contributes to this ability. Accordingly, by using murine macrophages and human macrophage-like phagocytic cell lines we investigated if PEA decoration of gonococcal lipid A modulates autophagy formation. We report that infection with PEA-lipid A-producing gonococci significantly reduced autophagy flux in murine and human macrophages and enhanced gonococcal survival during their association with macrophages compared to a PEA-deficient lipid A mutant. Our results provide further evidence that PEA-lipid A produced by gonococci is a critical component in the ability of this human pathogen to evade host defenses.

Macrophage-mediated gliadin degradation and concomitant IL-27 production drive IL-10- and IFN-γ-secreting Tr1-like-cell differentiation in a murine model for gluten tolerance.

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van Leeuwen, M A; Costes, L M M; van Berkel, L A; Simons-Oosterhuis, Y; du Pré, M F; Kozijn, A E; Raatgeep, H C; Lindenbergh-Kortleve, D J; van Rooijen, N; Koning, F; Samsom, J N

2017-05-01

Celiac disease is caused by inflammatory T-cell responses against the insoluble dietary protein gliadin. We have shown that, in humanized mice, oral tolerance to deamidated chymotrypsin-digested gliadin (CT-TG2-gliadin) is driven by tolerogenic interferon (IFN)-γ- and interleukin (IL)-10-secreting type 1 regulatory T-like cells (Tr1-like cells) generated in the spleen but not in the mesenteric lymph nodes. We aimed to uncover the mechanisms underlying gliadin-specific Tr1-like-cell differentiation and hypothesized that proteolytic gliadin degradation by splenic macrophages is a decisive step in this process. In vivo depletion of macrophages caused reduced differentiation of splenic IFN-γ- and IL-10-producing Tr1-like cells after CT-TG2-gliadin but not gliadin peptide feed. Splenic macrophages, rather than dendritic cells, constitutively expressed increased mRNA levels of the endopeptidase Cathepsin D; macrophage depletion significantly reduced splenic Cathepsin D expression in vivo and Cathepsin D efficiently degraded recombinant γ-gliadin in vitro. In response to CT-TG2-gliadin uptake, macrophages enhanced the expression of Il27p28, a cytokine that favored differentiation of gliadin-specific Tr1-like cells in vitro, and was previously reported to increase Cathepsin D activity. Conversely, IL-27 neutralization in vivo inhibited splenic IFN-γ- and IL-10-secreting Tr1-like-cell differentiation after CT-TG2-gliadin feed. Our data infer that endopeptidase mediated gliadin degradation by macrophages and concomitant IL-27 production drive differentiation of splenic gliadin-specific Tr1-like cells.

Blockade of MMP14 Activity in Murine Breast Carcinomas: Implications for Macrophages, Vessels, and Radiotherapy

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Ager, Eleanor I.; Kozin, Sergey V.; Kirkpatrick, Nathaniel D.; Seano, Giorgio; Kodack, David P.; Askoxylakis, Vasileios; Huang, Yuhui; Goel, Shom; Snuderl, Matija; Muzikansky, Alona; Finkelstein, Dianne M.; Dransfield, Daniel T.; Devy, Laetitia; Boucher, Yves

2015-01-01

Background: Matrix metalloproteinase (MMP) 14 may mediate tumor progression through vascular and immune-modulatory effects. Methods: Orthotopic murine breast tumors (4T1 and E0771 with high and low MMP14 expression, respectively; n = 5–10 per group) were treated with an anti-MMP14 inhibitory antibody (DX-2400), IgG control, fractionated radiation therapy, or their combination. We assessed primary tumor growth, transforming growth factor β (TGFβ) and inducible nitric oxide synthase (iNOS) expression, macrophage phenotype, and vascular parameters. A linear mixed model with repeated observations, with Mann-Whitney or analysis of variance with Bonferroni post hoc adjustment, was used to determine statistical significance. All statistical tests were two-sided. Results: DX-2400 inhibited tumor growth compared with IgG control treatment, increased macrophage numbers, and shifted the macrophage phenotype towards antitumor M1-like. These effects were associated with a reduction in active TGFβ and SMAD2/3 signaling. DX-2400 also transiently increased iNOS expression and tumor perfusion, reduced tissue hypoxia (median % area: control, 20.2%, interquartile range (IQR) = 6.4%-38.9%; DX-2400: 1.2%, IQR = 0.2%-3.2%, P = .044), and synergistically enhanced radiation therapy (days to grow to 800mm3: control, 12 days, IQR = 9–13 days; DX-2400 plus radiation, 29 days, IQR = 26–30 days, P < .001) in the 4T1 model. The selective iNOS inhibitor, 1400W, abolished the effects of DX-2400 on vessel perfusion and radiotherapy. On the other hand, DX-2400 was not capable of inducing iNOS expression or synergizing with radiation in E0771 tumors. Conclusion: MMP14 blockade decreased immunosuppressive TGFβ, polarized macrophages to an antitumor phenotype, increased iNOS, and improved tumor perfusion, resulting in reduced primary tumor growth and enhanced response to radiation therapy, especially in high MMP14-expressing tumors. PMID:25710962

Mechanism of cellular uptake and impact of ferucarbotran on macrophage physiology.

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Chung-Yi Yang

Full Text Available Superparamagnetic iron oxide (SPIO nanoparticles are contrast agents used for magnetic resonance imaging. Ferucarbotran is a clinically approved SPIO-coated carboxydextran with a diameter of about 45-60 nm. We investigated the mechanism of cellular uptake of Ferucarbotran with a cell model using the murine macrophage cell line Raw 264.7. We observed a dose-dependent uptake of these SPIO particles by spectrophotometer analysis and also a dose-dependent increase in the granularity of the macrophages as determined by flow cytometry. There was a linear correlation between the side scattering mean value and iron content (P<0.001, R(2 = 0. 8048. For evaluation of the endocytotic pathway of these ingested SPIO particles, different inhibitors of the endocytotic pathways were employed. There was a significant decrease of side scattering counts in the cells and a less significant change in signal intensity based on magnetic resonance in the phenylarsine oxide-treated macrophages. After labeling with SPIO particles, the macrophages showed an increase in the production of reactive oxygen species at 2, 24, and 48 h; a decrease in mitochondrial membrane potential at 24 h; and an increase in cell proliferation at 24 h. We concluded that Ferucarbotran was internalized into macrophages via the clathrin-mediated pathway and can change the cellular behavior of these cells after labeling.

Autophagy induced by silica nanoparticles protects RAW264.7 macrophages from cell death.

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Marquardt, Clarissa; Fritsch-Decker, Susanne; Al-Rawi, Marco; Diabaté, Silvia; Weiss, Carsten

2017-03-15

Although the technological and economic benefits of engineered nanomaterials are obvious, concerns have been raised about adverse effects if such material is inhaled, ingested, applied to the skin or even released into the environment. Here we studied the cytotoxic effects of the most abundant nanomaterial, silica nanoparticles (SiO 2 -NPs), in murine RAW264.7 macrophages. SiO 2 -NPs dose-dependently induce membrane leakage and cell death without obvious involvement of reactive oxygen species. Interestingly, at low concentrations SiO 2 -NPs trigger autophagy, evidenced by morphological and biochemical hallmarks such as autophagolysosomes or increased levels of LC3-II, which serves to protect cells from cytotoxicity. Hence SiO 2 -NPs initiate an adaptive stress response which dependent on dose serve to balance survival and death and ultimately dictates the cellular fate. Copyright © 2017 Elsevier B.V. All rights reserved.

Role of Granulocyte-Macrophage Colony-Stimulating Factor Production by T Cells during Mycobacterium tuberculosis Infection.

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Rothchild, Alissa C; Stowell, Britni; Goyal, Girija; Nunes-Alves, Cláudio; Yang, Qianting; Papavinasasundaram, Kadamba; Sassetti, Christopher M; Dranoff, Glenn; Chen, Xinchun; Lee, Jinhee; Behar, Samuel M

2017-10-24

Mice deficient for granulocyte-macrophage colony-stimulating factor (GM-CSF -/- ) are highly susceptible to infection with Mycobacterium tuberculosis , and clinical data have shown that anti-GM-CSF neutralizing antibodies can lead to increased susceptibility to tuberculosis in otherwise healthy people. GM-CSF activates human and murine macrophages to inhibit intracellular M. tuberculosis growth. We have previously shown that GM-CSF produced by iNKT cells inhibits growth of M. tuberculosis However, the more general role of T cell-derived GM-CSF during infection has not been defined and how GM-CSF activates macrophages to inhibit bacterial growth is unknown. Here we demonstrate that, in addition to nonconventional T cells, conventional T cells also produce GM-CSF during M. tuberculosis infection. Early during infection, nonconventional iNKT cells and γδ T cells are the main source of GM-CSF, a role subsequently assumed by conventional CD4 + T cells as the infection progresses. M. tuberculosis -specific T cells producing GM-CSF are also detected in the peripheral blood of infected people. Under conditions where nonhematopoietic production of GM-CSF is deficient, T cell production of GM-CSF is protective and required for control of M. tuberculosis infection. However, GM-CSF is not required for T cell-mediated protection in settings where GM-CSF is produced by other cell types. Finally, using an in vitro macrophage infection model, we demonstrate that GM-CSF inhibition of M. tuberculosis growth requires the expression of peroxisome proliferator-activated receptor gamma (PPARγ). Thus, we identified GM-CSF production as a novel T cell effector function. These findings suggest that a strategy augmenting T cell production of GM-CSF could enhance host resistance against M. tuberculosis IMPORTANCE Mycobacterium tuberculosis is the bacterium that causes tuberculosis, the leading cause of death by any infection worldwide. T cells are critical components of the immune

Accumulation of M1-like macrophages in type 2 diabetic islets is followed by a systemic shift in macrophage polarization.

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Cucak, Helena; Grunnet, Lars Groth; Rosendahl, Alexander

2014-01-01

Human T2D is characterized by a low-grade systemic inflammation, loss of β-cells, and diminished insulin production. Local islet immunity is still poorly understood, and hence, we evaluated macrophage subpopulations in pancreatic islets in the well-established murine model of T2D, the db/db mouse. Already at 8 weeks of disease, on average, 12 macrophages were observed in the diabetic islets, whereas only two were recorded in the nondiabetic littermates. On a detailed level, the islet resident macrophages increased fourfold compared with nondiabetic littermates, whereas a pronounced recruitment (eightfold) of a novel subset of macrophages (CD68+F4/80-) was observed. The majority of the CD68+F4/80+ but only 40% of the CD68+F4/80- islet macrophages expressed CD11b. Both islet-derived macrophage subsets expressed moderate MHC-II, high galectin-3, and low CD80/CD86 levels, suggesting the cells to be macrophages rather than DCs. On a functional level, the vast majority of the macrophages in the diabetic islets was of the proinflammatory, M1-like phenotype. The systemic immunity in diabetic animals was characterized by a low-grade inflammation with elevated cytokine levels and increase of splenic cytokine, producing CD68+F4/80- macrophages. In late-stage diabetes, the cytokine signature changed toward a TGF-β-dominated profile, coinciding with a significant increase of galectin-3-positive macrophages in the spleen. In summary, our results show that proinflammatory M1-like galectin-3+ CD80/CD86(low) macrophages invade diabetic islets. Moreover, the innate immunity matures in a diabetes-dependent manner from an initial proinflammatory toward a profibrotic phenotype, supporting the concept that T2D is an inflammatory disease.

Gliadin stimulation of murine macrophage inflammatory gene expression and intestinal permeability are MyD88-dependent: role of the innate immune response in Celiac disease.

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Thomas, Karen E; Sapone, Anna; Fasano, Alessio; Vogel, Stefanie N

2006-02-15

Recent studies have demonstrated the importance of TLR signaling in intestinal homeostasis. Celiac disease (CD) is an autoimmune enteropathy triggered in susceptible individuals by the ingestion of gliadin-containing grains. In this study, we sought to test the hypothesis that gliadin initiates this response by stimulating the innate immune response to increase intestinal permeability and by up-regulating macrophage proinflammatory gene expression and cytokine production. To this end, intestinal permeability and the release of zonulin (an endogenous mediator of gut permeability) in vitro, as well as proinflammatory gene expression and cytokine release by primary murine macrophage cultures, were measured. Gliadin and its peptide derivatives, 33-mer and p31-43, were found to be potent inducers of both a zonulin-dependent increase in intestinal permeability and macrophage proinflammatory gene expression and cytokine secretion. Gliadin-induced zonulin release, increased intestinal permeability, and cytokine production were dependent on myeloid differentiation factor 88 (MyD88), a key adapter molecule in the TLR/IL-1R signaling pathways, but were neither TLR2- nor TLR4-dependent. Our data support the following model for the innate immune response to gliadin in the initiation of CD. Gliadin interaction with the intestinal epithelium increases intestinal permeability through the MyD88-dependent release of zonulin that, in turn, enables paracellular translocation of gliadin and its subsequent interaction with macrophages within the intestinal submucosa. There, the interaction of gliadin with macrophages elicits a MyD88-dependent proinflammatory cytokine milieu that facilitates the interaction of T cells with APCs, leading ultimately to the Ag-specific adaptive immune response seen in patients with CD.

Viral infection of human lung macrophages increases PDL1 expression via IFNβ.

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Karl J Staples

Full Text Available Lung macrophages are an important defence against respiratory viral infection and recent work has demonstrated that influenza-induced macrophage PDL1 expression in the murine lung leads to rapid modulation of CD8+ T cell responses via the PD1 receptor. This PD1/PDL1 pathway may downregulate acute inflammatory responses to prevent tissue damage. The aim of this study was to investigate the mechanisms of PDL1 regulation by human macrophages in response to viral infection. Ex-vivo viral infection models using influenza and RSV were established in human lung explants, isolated lung macrophages and monocyte-derived macrophages (MDM and analysed by flow cytometry and RT-PCR. Incubation of lung explants, lung macrophages and MDM with X31 resulted in mean cellular infection rates of 18%, 18% and 29% respectively. Viral infection significantly increased cell surface expression of PDL1 on explant macrophages, lung macrophages and MDM but not explant epithelial cells. Infected MDM induced IFNγ release from autologous CD8+ T cells, an effect enhanced by PDL1 blockade. We observed increases in PDL1 mRNA and IFNβ mRNA and protein release by MDM in response to influenza infection. Knockdown of IFNβ by siRNA, resulted in a 37.5% reduction in IFNβ gene expression in response to infection, and a significant decrease in PDL1 mRNA. Furthermore, when MDM were incubated with IFNβ, this cytokine caused increased expression of PDL1 mRNA. These data indicate that human macrophage PDL1 expression modulates CD8+ cell IFNγ release in response to virus and that this expression is regulated by autologous IFNβ production.

Pro-inflammatory effects and oxidative stress in lung macrophages and epithelial cells induced by ambient particulate matter.

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Michael, S; Montag, M; Dott, W

2013-12-01

The objective of this study was to compare the toxicological effects of different source-related ambient PM10 samples in regard to their chemical composition. In this context we investigated airborne PM from different sites in Aachen, Germany. For the toxicological investigation human alveolar epithelial cells (A549) and murine macrophages (RAW264.7) were exposed from 0 to 96 h to increasing PM concentrations (0-100 μg/ml) followed by analyses of cell viability, pro-inflammatory and oxidative stress responses. The chemical analysis of these particles indicated the presence of 21 elements, water-soluble ions and PAHs. The toxicological investigations of the PM10 samples demonstrated a concentration- and time-dependent decrease in cell viability and an increase in pro-inflammatory and oxidative stress markers. Copyright © 2013 Elsevier Ltd. All rights reserved.

Of macrophages and red blood cells; a complex love story.

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Djuna Zoe de Back

2014-01-01

Full Text Available Macrophages tightly control the production and clearance of red blood cells (RBC. During steady state haematopoiesis, approximately 1010 red blood cells are produced per hour within erythroblastic islands in humans. In these erythroblastic islands, resident bone marrow macrophages provide erythroblasts with interactions that are essential for erythroid development. New evidence suggests that not only under homeostasis but also under stress conditions, macrophages play an important role in promoting erythropoiesis. Once RBC have matured, these cells remain in circulation for about 120 days. At the end of their life span, RBC are cleared by macrophages residing in the spleen and the liver. Current theories about the removal of senescent RBC and the essential role of macrophages will be discussed as well as the role of macrophages in facilitating the removal of damaged cellular content from the RBC. In this review we will provide an overview on the role of macrophages in the regulation of RBC production, maintenance and clearance. In addition, we will discuss the interactions between these two cell types during transfer of immune complexes and pathogens from RBC to macrophages.

Reprogramming of B cells into macrophages: mechanistic insights

OpenAIRE

Di Tullio, Alessandro, 1982-

2012-01-01

Our earlier work has shown that pre-B cells can be converted into macrophages by the transcription factor C/EBPα at very high frequencies and also that a clonal pre-B cell line with an inducible form of C/EBPα can be converted into macrophage-like cells. Using these systems we have performed a systematic analysis of the questions whether during transdifferentiation the cells retrodifferentiate to a precursor cell state and whether cell cycle is required for reprogramming. As for the first ...

Inhibitors of nuclear factor kappa B cause apoptosis in cultured macrophages

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E. E. Mannick

1997-01-01

Full Text Available The precise role of the transcription factor nuclear factor kappa B (NF- κB in the regulation of cell survival and cell death is still unresolved and may depend on cell type and position in the cell cycle. The aim of this study was to determine if three pharmacologic inhibitors of NF-κB, pyrrolidine dithiocarbamate, N-tosyl-L-lysl chloromethyl ketone and calpain I inhibitor, induce apoptosis in a murine macrophage cell line (RAW 264.7 at doses similar to those required for NF-κB inhibition. We found that each of the three inhibitors resulted in a dose- and time-dependent increase in morphologic indices of apoptosis in unstimulated, LPS-stimulated and TNF-stimulated cells. Lethal doses were consistent with those required for NF- κB inhibition. We conclude that nuclear NF-κB activation may represent an important survival mechanism in macrophages.

Acrolein increases 5-lipoxygenase expression in murine macrophages through activation of ERK pathway.

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Kim, Chae E; Lee, Seung J; Seo, Kyo W; Park, Hye M; Yun, Jung W; Bae, Jin U; Bae, Sun S; Kim, Chi D

2010-05-15

Episodic exposure to acrolein-rich pollutants has been linked to acute myocardial infarction, and 5-lipoxygenase (5-LO) is involved in the production of matrix metalloproteinase-9 (MMP-9), which destabilizes atherosclerotic plaques. Thus, the present study determined the effect of acrolein on 5-LO/leukotriene B(4) (LTB(4)) production in murine macrophages. Stimulation of J774A.1 cells with acrolein led to increased LTB(4) production in association with increased 5-LO expression. Acrolein-evoked 5-LO expression was blocked by pharmacological inhibition of the ERK pathway, but not by inhibitors for JNK and p38 MAPK pathways. In line with these results, acrolein exclusively increased the phosphorylation of ERK among these MAPK, suggesting a role for the ERK pathway in acrolein-induced 5-LO expression with subsequent production of LTB(4). Among the receptor tyrosine kinases including epidermal growth factor receptor (EGFR) and platelet derived growth factor receptor (PDGFR), acrolein-evoked ERK phosphorylation was attenuated by AG1478, an EGFR inhibitor, but not by AG1295, a PDGFR inhibitor. In addition, acrolein-evoked 5-LO expression was also inhibited by inhibition of EGFR pathway, but not by inhibition of PDGFR pathway. These observations suggest that acrolein has a profound effect on the 5-LO pathway via an EGFR-mediated activation of ERK pathway, leading to acute ischemic syndromes through the generation of LTB(4), subsequent MMP-9 production and plaque rupture.

Acrolein increases 5-lipoxygenase expression in murine macrophages through activation of ERK pathway

International Nuclear Information System (INIS)

Kim, Chae E.; Lee, Seung J.; Seo, Kyo W.; Park, Hye M.; Yun, Jung W.; Bae, Jin U.; Bae, Sun S.; Kim, Chi D.

2010-01-01

Episodic exposure to acrolein-rich pollutants has been linked to acute myocardial infarction, and 5-lipoxygenase (5-LO) is involved in the production of matrix metalloproteinase-9 (MMP-9), which destabilizes atherosclerotic plaques. Thus, the present study determined the effect of acrolein on 5-LO/leukotriene B 4 (LTB 4 ) production in murine macrophages. Stimulation of J774A.1 cells with acrolein led to increased LTB 4 production in association with increased 5-LO expression. Acrolein-evoked 5-LO expression was blocked by pharmacological inhibition of the ERK pathway, but not by inhibitors for JNK and p38 MAPK pathways. In line with these results, acrolein exclusively increased the phosphorylation of ERK among these MAPK, suggesting a role for the ERK pathway in acrolein-induced 5-LO expression with subsequent production of LTB 4 . Among the receptor tyrosine kinases including epidermal growth factor receptor (EGFR) and platelet derived growth factor receptor (PDGFR), acrolein-evoked ERK phosphorylation was attenuated by AG1478, an EGFR inhibitor, but not by AG1295, a PDGFR inhibitor. In addition, acrolein-evoked 5-LO expression was also inhibited by inhibition of EGFR pathway, but not by inhibition of PDGFR pathway. These observations suggest that acrolein has a profound effect on the 5-LO pathway via an EGFR-mediated activation of ERK pathway, leading to acute ischemic syndromes through the generation of LTB 4 , subsequent MMP-9 production and plaque rupture.

Tie2 signaling cooperates with TNF to promote the pro-inflammatory activation of human macrophages independently of macrophage functional phenotype.

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García, Samuel; Krausz, Sarah; Ambarus, Carmen A; Fernández, Beatriz Malvar; Hartkamp, Linda M; van Es, Inge E; Hamann, Jörg; Baeten, Dominique L; Tak, Paul P; Reedquist, Kris A

2014-01-01

Angiopoietin (Ang) -1 and -2 and their receptor Tie2 play critical roles in regulating angiogenic processes during development, homeostasis, tumorigenesis, inflammation and tissue repair. Tie2 signaling is best characterized in endothelial cells, but a subset of human and murine circulating monocytes/macrophages essential to solid tumor formation express Tie2 and display immunosuppressive properties consistent with M2 macrophage polarization. However, we have recently shown that Tie2 is strongly activated in pro-inflammatory macrophages present in rheumatoid arthritis patient synovial tissue. Here we examined the relationship between Tie2 expression and function during human macrophage polarization. Tie2 expression was observed under all polarization conditions, but was highest in IFN-γ and IL-10 -differentiated macrophages. While TNF enhanced expression of a common restricted set of genes involved in angiogenesis and inflammation in GM-CSF, IFN-γ and IL-10 -differentiated macrophages, expression of multiple chemokines and cytokines, including CXCL3, CXCL5, CXCL8, IL6, and IL12B was further augmented in the presence of Ang-1 and Ang-2, via Tie2 activation of JAK/STAT signaling. Conditioned medium from macrophages stimulated with Ang-1 or Ang-2 in combination with TNF, sustained monocyte recruitment. Our findings suggest a general role for Tie2 in cooperatively promoting the inflammatory activation of macrophages, independently of polarization conditions.

Notch signaling regulates expression of Mcl-1 and apoptosis in PPD-treated macrophages.

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Palaga, Tanapat; Ratanabunyong, Siriluk; Pattarakankul, Thitiporn; Sangphech, Naunpun; Wongchana, Wipawee; Hadae, Yukihiro; Kueanjinda, Patipark

2013-09-01

Macrophages are cellular targets for infection by bacteria and viruses. The fate of infected macrophages plays a key role in determining the outcome of the host immune response. Apoptotic cell death of macrophages is considered to be a protective host defense that eliminates pathogens and infected cells. In this study, we investigated the involvement of Notch signaling in regulating apoptosis in macrophages treated with tuberculin purified protein derivative (PPD). Murine bone marrow-derived macrophages (BMMs) treated with PPD or infected with Mycobacterium bovis Bacillus Calmette-Guérin (BCG) induced upregulation of Notch1. This upregulation correlated well with the upregulation of the anti-apoptotic gene mcl-1 both at the transcriptional and translational levels. Decreased levels of Notch1 and Mcl-1 were observed in BMM treated with PPD when a gamma secretase inhibitor (GSI), which inhibits the processing of Notch receptors, was used. Moreover, silencing Notch1 in the macrophage-like cell line RAW264.7 decreased Mcl-1 protein expression, suggesting that Notch1 is critical for Mcl-1 expression in macrophages. A significant increase in apoptotic cells was observed upon treatment of BMM with PPD in the presence of GSI compared to the vehicle-control treated cells. Finally, analysis of the mcl-1 promoter in humans and mice revealed a conserved potential CSL/RBP-Jκ binding site. The association of Notch1 with the mcl-1 promoter was confirmed by chromatin immunoprecipitation. Taken together, these results indicate that Notch1 inhibits apoptosis of macrophages stimulated with PPD by directly controlling the mcl-1 promoter.

Photothermal enhancement of chemotherapy mediated by gold-silica nanoshell-loaded macrophages: in vitro squamous cell carcinoma study

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Madsen, Steen J.; Shih, En-Chung; Peng, Qian; Christie, Catherine; Krasieva, Tatiana; Hirschberg, Henry

2016-01-01

Moderate hyperthermia (MHT) has been shown to enhance the effects of chemotherapeutic agents in a wide variety of cancers. The purpose of this study was to investigate the combined effects of commonly used chemotherapeutic agents with MHT induced by near-infrared (NIR) activation of gold nanoshell (AuNS)-loaded macrophages (Ma). AuNS-loaded murine Ma combined with human FaDu squamous cells, in hybrid monolayers, were subjected to three cytotoxic drugs (doxorubicin, bleomycin, cisplatin) with or without NIR laser irradiation. For all three drugs, efficacy was increased by NIR activation of AuNS-loaded Ma. The results of this in vitro study provide proof-of-concept for the use of AuNS-loaded Ma for photothermal enhancement of the effects of chemotherapy on squamous cell carcinoma.

Characteristic features of intracellular pathogenic Leptospira in infected murine macrophages.

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Toma, Claudia; Okura, Nobuhiko; Takayama, Chitoshi; Suzuki, Toshihiko

2011-11-01

Leptospira interrogans is a spirochaete responsible for a zoonotic disease known as leptospirosis. Leptospires are able to penetrate the abraded skin and mucous membranes and rapidly disseminate to target organs such as the liver, lungs and kidneys. How this pathogen escape from innate immune cells and spread to target organs remains poorly understood. In this paper, the intracellular trafficking undertaken by non-pathogenic Leptospira biflexa and pathogenic L. interrogans in mouse bone marrow-derived macrophages was compared. The delayed in the clearance of L. interrogans was observed. Furthermore, the acquisition of lysosomal markers by L. interrogans-containing phagosomes lagged behind that of L. biflexa-containing phagosomes, and although bone marrow-derived macrophages could degrade L. biflexa as well as L. interrogans, a population of L. interrogans was able to survive and replicate. Intact leptospires were found within vacuoles at 24 h post infection, suggesting that bacterial replication occurs within a membrane-bound compartment. In contrast, L. biflexa were completely degraded at 24 h post infection. Furthermore, L. interrogans but not L. biflexa, were released to the extracellular milieu. These results suggest that pathogenic leptospires are able to survive, replicate and exit from mouse macrophages, enabling their eventual spread to target organs. © 2011 Blackwell Publishing Ltd.

Macrophage phenotypic subtypes diametrically regulate epithelial-mesenchymal plasticity in breast cancer cells

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Yang, Min; Ma, Bo; Shao, Hanshuang; Clark, Amanda M.; Wells, Alan

2016-01-01

Metastatic progression of breast cancer involves phenotypic plasticity of the carcinoma cells moving between epithelial and mesenchymal behaviors. During metastatic seeding and dormancy, even highly aggressive carcinoma cells take on an E-cadherin-positive epithelial phenotype that is absent from the emergent, lethal metastatic outgrowths. These phenotypes are linked to the metastatic microenvironment, though the specific cells and induction signals are still to be deciphered. Recent evidence suggests that macrophages impact tumor progression, and may alter the balance between cancer cell EMT and MErT in the metastatic microenvironment. Here we explore the role of M1/M2 macrophages in epithelial-mesenchymal plasticity of breast cancer cells by coculturing epithelial and mesenchymal cells lines with macrophages. We found that after polarizing the THP-1 human monocyte cell line, the M1 and M2-types were stable and maintained when co-cultured with breast cancer cells. Surprisingly, M2 macrophages may conferred a growth advantage to the epithelial MCF-7 cells, with these cells being driven to a partial mesenchymal phenotypic as indicated by spindle morphology. Notably, E-cadherin protein expression is significantly decreased in MCF-7 cells co-cultured with M2 macrophages. M0 and M1 macrophages had no effect on the MCF-7 epithelial phenotype. However, the M1 macrophages impacted the highly aggressive mesenchymal-like MDA-MB-231 breast cancer cells to take on a quiescent, epithelial phenotype with re-expression of E-cadherin. The M2 macrophages if anything exacerbated the mesenchymal phenotype of the MDA-MB-231 cells. Our findings demonstrate M2 macrophages might impart outgrowth and M1 macrophages may contribute to dormancy behaviors in metastatic breast cancer cells. Thus EMT and MErT are regulated by selected macrophage phenotype in the liver metastatic microenvironment. These results indicate macrophage could be a potential therapeutic target for limiting death due

Of macrophages and red blood cells; a complex love story.

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de Back, Djuna Z; Kostova, Elena B; van Kraaij, Marian; van den Berg, Timo K; van Bruggen, Robin

2014-01-01

Macrophages tightly control the production and clearance of red blood cells (RBC). During steady state hematopoiesis, approximately 10(10) RBC are produced per hour within erythroblastic islands in humans. In these erythroblastic islands, resident bone marrow macrophages provide erythroblasts with interactions that are essential for erythroid development. New evidence suggests that not only under homeostasis but also under stress conditions, macrophages play an important role in promoting erythropoiesis. Once RBC have matured, these cells remain in circulation for about 120 days. At the end of their life span, RBC are cleared by macrophages residing in the spleen and the liver. Current theories about the removal of senescent RBC and the essential role of macrophages will be discussed as well as the role of macrophages in facilitating the removal of damaged cellular content from the RBC. In this review we will provide an overview on the role of macrophages in the regulation of RBC production, maintenance and clearance. In addition, we will discuss the interactions between these two cell types during transfer of immune complexes and pathogens from RBC to macrophages.

TLR Stimulation Dynamically Regulates Heme and Iron Export Gene Expression in Macrophages

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Mary Philip

2016-01-01

Full Text Available Pathogenic bacteria have evolved multiple mechanisms to capture iron or iron-containing heme from host tissues or blood. In response, organisms have developed defense mechanisms to keep iron from pathogens. Very little of the body’s iron store is available as free heme; rather nearly all body iron is complexed with heme or other proteins. The feline leukemia virus, subgroup C (FeLV-C receptor, FLVCR, exports heme from cells. It was unknown whether FLVCR regulates heme-iron availability after infection, but given that other heme regulatory proteins are upregulated in macrophages in response to bacterial infection, we hypothesized that macrophages dynamically regulate FLVCR. We stimulated murine primary macrophages or macrophage cell lines with LPS and found that Flvcr is rapidly downregulated in a TLR4/MD2-dependent manner; TLR1/2 and TLR3 stimulation also decreased Flvcr expression. We identified several candidate TLR-activated transcription factors that can bind to the Flvcr promoter. Macrophages must balance the need to sequester iron from systemic circulating or intracellular pathogens with the macrophage requirement for heme and iron to produce reactive oxygen species. Our findings underscore the complexity of this regulation and point to a new role for FLVCR and heme export in macrophages responses to infection and inflammation.

Cell-mediated immune response to syngeneic uv induced tumors. I. The presence of tumor associated macrophages and their possible role in the in vitro generation of cytotoxic lymphocytes

International Nuclear Information System (INIS)

Woodward, J.G.; Daynes, R.A.

1978-01-01

A primary in vitro sensitization system employing a chromium release assay was utilized to investigate reactivity of murine spleen cells toward syngeneic ultraviolet (uv) light induced fibrosarcomas. These tumors are immunologically rejected in vivo when implanted into normal syngeneic mice but grow progressively when implanted into syngeneic mice that had previously been irradiated with subcarcinogenic levels of uv light. Following appropriate sensitization, spleen cells from both normal and uv irradiated mice are capable of developing cytotoxic lymphocytes in vitro against the uv induced tumors. It was subsequently discovered that in situ uv induced tumors all contained macrophages of host origin that became demonstrable only after enzymatic dissociation of the tumor tissue. These macrophages were immunologically active in vitro as their presence in the stimulator cell population was necessary to achieve an optimum anti-tumor cytotoxic response following in vitro sensitization. Anti-tumor reactivity generated by mixing spleen cells and tumor cells in the absence of tumor derived macrophages could be greatly enhanced by the addition of normal syngeneic peritoneal macrophages. When in vitro anti-tumor reactivity of spleen cells from normal and uv treated mice was compared under these conditions we again found no significant difference in the magnitude of the responses. In addition, the cytotoxic cells generated in response to uv induced tumors appeared to be highly cross reactive with respect to their killing potential

Small cell lung cancer: Recruitment of macrophages by circulating tumor cells.

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Hamilton, Gerhard; Rath, Barbara; Klameth, Lukas; Hochmair, Maximilan J

2016-03-01

Tumor-associated macrophages (TAMs) play an important role in tumor progression, suppression of antitumor immunity and dissemination. Blood monocytes infiltrate the tumor region and are primed by local microenvironmental conditions to promote tumor growth and invasion. Although many of the interacting cytokines and factors are known for the tumor-macrophage interactions, the putative contribution of circulating tumor cells (CTCs) is not known so far. These specialized cells are characterized by increased mobility, ability to degrade the extracellular matrix (ECM) and to enter the blood stream and generate secondary lesions which is a leading cause of death for the majority of tumor patients. The first establishment of two permanent CTC lines, namely BHGc7 and 10, from blood samples of advanced stage small cell lung cancer (SCLC) patients allowed us to investigate the CTC-immune cell interaction. Cocultures of peripheral blood mononuclear cells (PBMNCs) with CTCs or addition of CTC-conditioned medium (CTC-CM) in vitro resulted in monocyte-macrophage differentiation and appearance of CD14 + , CD163 weak and CD68 + macrophages expressing markers of TAMs. Furthermore, we screened the supernatants of CTC-primed macrophages for presence of approximately 100 cytokines and compared the expression with those induced by the local metastatic SCLC26A cell line. Macrophages recruited by SCLC26A-CM showed expression of osteopontin (OPN), monocyte chemoattractant protein-1 (MCP-1), IL-8, chitinase3-like 1 (CHI3L1), platelet factor (Pf4), IL-1ra and matrix metalloproteinase-9 (MMP-9) among other minor cytokines/chemokines. In contrast, BHGc7-CM induced marked overexpression of complement factor D (CFD)/adipsin and vitamin D-BP (VDBP), as well as increased secretion of OPN, lipocalin-2 (LCN2), CHI3L1, uPAR, MIP-1 and GDF-15/MIC-1. BHGc10, derived independently from relapsed SCLC, revealed an almost identical pattern with added expression of ENA-78/CXCL5. CMs of the non-tumor HEK293

[Macrophage colony stimulating factor enhances non-small cell lung cancer invasion and metastasis by promoting macrophage M2 polarization].

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Li, Y J; Yang, L; Wang, L P; Zhang, Y

2017-06-23

Objective: To investigate the key cytokine which polarizes M2 macrophages and promotes invasion and metastasis in non-small cell lung cancer (NSCLC). Methods: After co-culture with A549 cells in vitro, the proportion of CD14(+) CD163(+) M2 macrophages in monocytes and macrophage colony stimulating factor (M-CSF) levels in culture supernatant were detected by flow cytometry, ELISA assay and real-time qPCR, respectively. The effects of CD14(+) CD163(+) M2 macrophages on invasion of A549 cells and angiogenesis of HUVEC cells were measured by transwell assay and tubule formation assay, respectively. The clinical and prognostic significance of M-CSF expression in NSCLC was further analyzed. Results: The percentage of CD14(+) CD163(+) M2 macrophages in monocytes and the concentration of M-CSF in the supernatant followed by co-culture was (12.03±0.46)% and (299.80±73.76)pg/ml, respectively, which were significantly higher than those in control group [(2.80±1.04)% and (43.07±11.22)pg/ml, respectively, P macrophages in vitro . M2 macrophages enhanced the invasion of A549 cells (66 cells/field vs. 26 cells/field) and the angiogenesis of HUVEC cells (22 tubes/field vs. 8 tubes/field). The mRNA expression of M-CSF in stage Ⅰ-Ⅱ patients (16.23±4.83) was significantly lower than that in stage Ⅲ-Ⅳ (53.84±16.08; P macrophages, which can further promote the metastasis and angiogenesis of NSCLC. M-CSF could be used as a potential therapeutic target of NSCLC.

Extra virgin olive oil polyphenolic extracts downregulate inflammatory responses in LPS-activated murine peritoneal macrophages suppressing NFκB and MAPK signalling pathways.

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Cárdeno, A; Sánchez-Hidalgo, M; Aparicio-Soto, M; Sánchez-Fidalgo, S; Alarcón-de-la-Lastra, C

2014-06-01

Extra virgin olive oil (EVOO) is obtained from the fruit of the olive tree Olea europaea L. Phenolic compounds present in EVOO have recognized anti-oxidant and anti-inflammatory properties. However, the activity of the total phenolic fraction extracted from EVOO and the action mechanisms involved are not well defined. The present study was designed to evaluate the potential anti-inflammatory mechanisms of the polyphenolic extract (PE) from EVOO on LPS-stimulated peritoneal murine macrophages. Nitric oxide (NO) production was analyzed by the Griess method and intracellular reactive oxygen species (ROS) by fluorescence analysis. Moreover, changes in the protein expression of the pro-inflammatory enzymes, inducible nitric oxide synthase (iNOS), cyclooxygenase (COX)-2 and microsomal prostaglandin E synthase-1 (mPGES-1), as well as the role of nuclear transcription factor kappa B (NFκB) and mitogen-activated protein kinase (MAPK) signalling pathways, were analyzed by Western blot. PE from EVOO reduced LPS-induced oxidative stress and inflammatory responses through decreasing NO and ROS generation. In addition, PE induced a significant down-regulation of iNOS, COX-2 and mPGES-1 protein expressions, reduced MAPK phosphorylation and prevented the nuclear NFκB translocation. This study establishes that PE from EVOO possesses anti-inflammatory activities on LPS-stimulated murine macrophages.

Intratumoral macrophages contribute to epithelial-mesenchymal transition in solid tumors

International Nuclear Information System (INIS)

Bonde, Anne-Katrine; Tischler, Verena; Kumar, Sushil; Soltermann, Alex; Schwendener, Reto A

2012-01-01

Several stromal cell subtypes including macrophages contribute to tumor progression by inducing epithelial-mesenchymal transition (EMT) at the invasive front, a mechanism also linked to metastasis. Tumor associated macrophages (TAM) reside mainly at the invasive front but they also infiltrate tumors and in this process they mainly assume a tumor promoting phenotype. In this study, we asked if TAMs also regulate EMT intratumorally. We found that TAMs through TGF-β signaling and activation of the β-catenin pathway can induce EMT in intratumoral cancer cells. We depleted macrophages in F9-teratocarcinoma bearing mice using clodronate-liposomes and analyzed the tumors for correlations between gene and protein expression of EMT-associated and macrophage markers. The functional relationship between TAMs and EMT was characterized in vitro in the murine F9 and mammary gland NMuMG cells, using a conditioned medium culture approach. The clinical relevance of our findings was evaluated on a tissue microarray cohort representing 491 patients with non-small cell lung cancer (NSCLC). Gene expression analysis of F9-teratocarcinomas revealed a positive correlation between TAM-densities and mesenchymal marker expression. Moreover, immunohistochemistry showed that TAMs cluster with EMT phenotype cells in the tumors. In vitro, long term exposure of F9-and NMuMG-cells to macrophage-conditioned medium led to decreased expression of the epithelial adhesion protein E-cadherin, activation of the EMT-mediating β-catenin pathway, increased expression of mesenchymal markers and an invasive phenotype. In a candidate based screen, macrophage-derived TGF-β was identified as the main inducer of this EMT-associated phenotype. Lastly, immunohistochemical analysis of NSCLC patient samples identified a positive correlation between intratumoral macrophage densities, EMT markers, intraepithelial TGF-β levels and tumor grade. Data presented here identify a novel role for macrophages in EMT

Biomaterials Influence Macrophage-Mesenchymal Stem Cell Interaction In Vitro

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N. Grotenhuis (Nienke); S.F. De Witte (Samantha Fh); G.J.V.M. van Osch (Gerjo); Y. Bayon (Yves); J.F. Lange (Johan); Y.M. Bastiaansen-Jenniskens (Yvonne)

2016-01-01

textabstractBackground: Macrophages and mesenchymal stem cells (MSCs) are important cells in wound healing. We hypothesized that the cross-talk between macrophages and adipose tissue-derived MSCs (ASCs) is biomaterial dependent, thereby influencing processes involved in wound healing. Materials and

Fine surface structure of unfixed and hydrated macrophages observed by laser-plasma x-ray contact microscopy

International Nuclear Information System (INIS)

Yamamoto, Yoshimasa; Friedman, Herman; Yoshimura, Hideyuki; Kinjo, Yasuhito; Shioda, Seiji; Debari, Kazuhiro; Shinohara, Kunio; Rajyaguru, Jayshree; Richardson, Martin

2000-01-01

A compact, high-resolution, laser-plasma, x-ray contact microscope using a table-top Nd:glass laser system has been developed and utilized for the analysis of the surface structure of live macrophages. Fine fluffy surface structures of murine peritoneal macrophages, which were live, hydrolyzed and not sliced and stained, were observed by the x-ray microscope followed by analysis using an atomic force microscopy. In order to compare with other techniques, a scanning electron microscopy (SEM) was utilized to observe the surface structure of the macrophages. The SEM offered a fine whole cell image of the same macrophages, which were fixed and dehydrated, but the surfaces were ruffled and different from that of x-ray images. A standard light microscope was also utilized to observe the shape of live whole macrophages. Light microscopy showed some fluffy surface structures of the macrophages, but the resolution was too low to observe the fine structures. Thus, the findings of fine fluffy surface structures of macrophages by x-ray microscopy provide valuable information for studies of phagocytosis, cell spreading and adherence, which are dependent on the surface structure of macrophages. Furthermore, the present study also demonstrates the usefulness of x-ray microscopy for analysis of structures of living cells

Glioblastoma-infiltrated innate immune cells resemble M0 macrophage phenotype

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Gabrusiewicz, Konrad; Rodriguez, Benjamin; Wei, Jun; Hashimoto, Yuuri; Healy, Luke M.; Maiti, Sourindra N.; Wang, Qianghu; Elakkad, Ahmed; Liebelt, Brandon D.; Yaghi, Nasser K.; Ezhilarasan, Ravesanker; Huang, Neal; Weinberg, Jeffrey S.; Prabhu, Sujit S.; Rao, Ganesh; Sawaya, Raymond; Langford, Lauren A.; Bruner, Janet M.; Fuller, Gregory N.; Bar-Or, Amit; Li, Wei; Colen, Rivka R.; Curran, Michael A.; Bhat, Krishna P.; Antel, Jack P.; Cooper, Laurence J.; Sulman, Erik P.; Heimberger, Amy B.

2016-01-01

Glioblastomas are highly infiltrated by diverse immune cells, including microglia, macrophages, and myeloid-derived suppressor cells (MDSCs). Understanding the mechanisms by which glioblastoma-associated myeloid cells (GAMs) undergo metamorphosis into tumor-supportive cells, characterizing the heterogeneity of immune cell phenotypes within glioblastoma subtypes, and discovering new targets can help the design of new efficient immunotherapies. In this study, we performed a comprehensive battery of immune phenotyping, whole-genome microarray analysis, and microRNA expression profiling of GAMs with matched blood monocytes, healthy donor monocytes, normal brain microglia, nonpolarized M0 macrophages, and polarized M1, M2a, M2c macrophages. Glioblastoma patients had an elevated number of monocytes relative to healthy donors. Among CD11b+ cells, microglia and MDSCs constituted a higher percentage of GAMs than did macrophages. GAM profiling using flow cytometry studies revealed a continuum between the M1- and M2-like phenotype. Contrary to current dogma, GAMs exhibited distinct immunological functions, with the former aligned close to nonpolarized M0 macrophages. PMID:26973881

Vascular endothelial growth factor modified macrophages transdifferentiate into endothelial-like cells and decrease foam cell formation.

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Yan, Dan; He, Yujuan; Dai, Jun; Yang, Lili; Wang, Xiaoyan; Ruan, Qiurong

2017-06-30

Macrophages are largely involved in the whole process of atherosclerosis from an initiation lesion to an advanced lesion. Endothelial disruption is the initial step and macrophage-derived foam cells are the hallmark of atherosclerosis. Promotion of vascular integrity and inhibition of foam cell formation are two important strategies for preventing atherosclerosis. How can we inhibit even the reverse negative role of macrophages in atherosclerosis? The present study was performed to investigate if overexpressing endogenous human vascular endothelial growth factor (VEGF) could facilitate transdifferentiation of macrophages into endothelial-like cells (ELCs) and inhibit foam cell formation. We demonstrated that VEGF-modified macrophages which stably overexpressed human VEGF (hVEGF 165 ) displayed a high capability to alter their phenotype and function into ELCs in vitro Exogenous VEGF could not replace endogenous VEGF to induce the transdifferentiation of macrophages into ELCs in vitro We further showed that VEGF-modified macrophages significantly decreased cytoplasmic lipid accumulation after treatment with oxidized LDL (ox-LDL). Moreover, down-regulation of CD36 expression in these cells was probably one of the mechanisms of reduction in foam cell formation. Our results provided the in vitro proof of VEGF-modified macrophages as atheroprotective therapeutic cells by both promotion of vascular repair and inhibition of foam cell formation. © 2017 The Author(s).

MicroRNA 27a-3p Regulates Antimicrobial Responses of Murine Macrophages Infected by Mycobacterium avium subspecies paratuberculosis by Targeting Interleukin-10 and TGF-β-Activated Protein Kinase 1 Binding Protein 2

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Tariq Hussain

2018-01-01

Full Text Available Mycobacterium avium subspecies paratuberculosis (MAP persistently survive and replicate in mononuclear phagocytic cells by adopting various strategies to subvert host immune response. Interleukin-10 (IL-10 upregulation via inhibition of macrophage bactericidal activity is a critical step for MAP survival and pathogenesis within the host cell. Mitogen-activated protein kinase p38 signaling cascade plays a crucial role in the elevation of IL-10 and progression of MAP pathogenesis. The contribution of microRNAs (miRNAs and their influence on the activation of macrophages during MAP pathogenesis are still unclear. In the current study, we found that miRNA-27a-3p (miR-27a expression is downregulated during MAP infection both in vivo and in vitro. Moreover, miR-27a is also downregulated in toll-like receptor 2 (TLR2-stimulated murine macrophages (RAW264.7 and bone marrow-derived macrophage. ELISA and real-time qRT-PCR results confirm that overexpression of miR-27a inhibited MAP-induced IL-10 production in macrophages and upregulated pro-inflammatory cytokines, while miR-27a inhibitor counteracted these effects. Luciferase reporter assay results revealed that IL-10 and TGF-β-activated protein kinase 1 binding protein 2 (TAB 2 are potential targets of miR-27a. In addition, we demonstrated that miR-27a negatively regulates TAB 2 expression and diminishes TAB 2-dependent p38/JNK phosphorylation, ultimately downregulating IL-10 expression in MAP-infected macrophages. Furthermore, overexpression of miR-27a significantly inhibited the intracellular survival of MAP in infected macrophages. Our data show that miR-27a augments antimicrobial activities of macrophages and inhibits the expression of IL-10, demonstrating that miR-27a regulates protective innate immune responses during MAP infection and can be exploited as a novel therapeutic target in the control of intracellular pathogens, including paratuberculosis.

Characterization of a resident population of adventitial macrophage progenitor cells in postnatal vasculature.

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Psaltis, Peter J; Puranik, Amrutesh S; Spoon, Daniel B; Chue, Colin D; Hoffman, Scott J; Witt, Tyra A; Delacroix, Sinny; Kleppe, Laurel S; Mueske, Cheryl S; Pan, Shuchong; Gulati, Rajiv; Simari, Robert D

2014-07-18

Macrophages regulate blood vessel structure and function in health and disease. The origins of tissue macrophages are diverse, with evidence for local production and circulatory renewal. We identified a vascular adventitial population containing macrophage progenitor cells and investigated their origins and fate. Single-cell disaggregates from adult C57BL/6 mice were prepared from different tissues and tested for their capacity to form hematopoietic colony-forming units. Aorta showed a unique predilection for generating macrophage colony-forming units. Aortic macrophage colony-forming unit progenitors coexpressed stem cell antigen-1 and CD45 and were adventitially located, where they were the predominant source of proliferating cells in the aortic wall. Aortic Sca-1(+)CD45(+) cells were transcriptionally and phenotypically distinct from neighboring cells lacking stem cell antigen-1 or CD45 and contained a proliferative (Ki67(+)) Lin(-)c-Kit(+)CD135(-)CD115(+)CX3CR1(+)Ly6C(+)CD11b(-) subpopulation, consistent with the immunophenotypic profile of macrophage progenitors. Adoptive transfer studies revealed that Sca-1(+)CD45(+) adventitial macrophage progenitor cells were not replenished via the circulation from bone marrow or spleen, nor was their prevalence diminished by depletion of monocytes or macrophages by liposomal clodronate treatment or genetic deficiency of macrophage colony-stimulating factor. Rather adventitial macrophage progenitor cells were upregulated in hyperlipidemic ApoE(-/-) and LDL-R(-/-) mice, with adventitial transfer experiments demonstrating their durable contribution to macrophage progeny particularly in the adventitia, and to a lesser extent the atheroma, of atherosclerotic carotid arteries. The discovery and characterization of resident vascular adventitial macrophage progenitor cells provides new insight into adventitial biology and its participation in atherosclerosis and provokes consideration of the broader existence of local macrophage

Pro-inflammatory effects and oxidative stress in lung macrophages and epithelial cells induced by ambient particulate matter

International Nuclear Information System (INIS)

Michael, S.; Montag, M.; Dott, W.

2013-01-01

The objective of this study was to compare the toxicological effects of different source-related ambient PM10 samples in regard to their chemical composition. In this context we investigated airborne PM from different sites in Aachen, Germany. For the toxicological investigation human alveolar epithelial cells (A549) and murine macrophages (RAW264.7) were exposed from 0 to 96 h to increasing PM concentrations (0–100 μg/ml) followed by analyses of cell viability, pro-inflammatory and oxidative stress responses. The chemical analysis of these particles indicated the presence of 21 elements, water-soluble ions and PAHs. The toxicological investigations of the PM10 samples demonstrated a concentration- and time-dependent decrease in cell viability and an increase in pro-inflammatory and oxidative stress markers. -- Highlights: ► The study compares the toxicological effects of different source-related particles with regard to their chemical composition. ► The chemical characterization of the coarse particles revealed clear differences in elemental, TC and PAH composition. ► Equal mass concentrations of urban traffic and rural PM caused different toxicological responses. ► The observations confirm the hypothesis that particle composition, as well as origin, influence the PM-induced toxicity. -- The toxicological responses of lung epithelial cells and macrophages differ significantly after an exposure to equal mass concentrations of urban traffic and rural PM

Ly6G-mediated depletion of neutrophils is dependent on macrophages.

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Bruhn, Kevin W; Dekitani, Ken; Nielsen, Travis B; Pantapalangkoor, Paul; Spellberg, Brad

2016-01-01

Antibody-mediated depletion of neutrophils is commonly used to study neutropenia. However, the mechanisms by which antibodies deplete neutrophils have not been well defined. We noticed that mice deficient in complement and macrophages had blunted neutrophil depletion in response to anti-Ly6G monoclonal antibody (MAb) treatment. In vitro, exposure of murine neutrophils to anti-Ly6G MAb in the presence of plasma did not result in significant depletion of cells, either in the presence or absence of complement. In vivo, anti-Ly6G-mediated neutrophil depletion was abrogated following macrophage depletion, but not complement depletion, indicating a requirement for macrophages to induce neutropenia by this method. These results inform the use and limitations of anti-Ly6G antibody as an experimental tool for depleting neutrophils in various immunological settings.

Apoptotic Cells Induced Signaling for Immune Homeostasis in Macrophages and Dendritic Cells

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Uriel Trahtemberg

2017-10-01

Full Text Available Inefficient and abnormal clearance of apoptotic cells (efferocytosis contributes to systemic autoimmune disease in humans and mice, and inefficient chromosomal DNA degradation by DNAse II leads to systemic polyarthritis and a cytokine storm. By contrast, efficient clearance allows immune homeostasis, generally leads to a non-inflammatory state for both macrophages and dendritic cells (DCs, and contributes to maintenance of peripheral tolerance. As many as 3 × 108 cells undergo apoptosis every hour in our bodies, and one of the primary “eat me” signals expressed by apoptotic cells is phosphatidylserine (PtdSer. Apoptotic cells themselves are major contributors to the “anti-inflammatory” nature of the engulfment process, some by secreting thrombospondin-1 (TSP-1 or adenosine monophosphate and possibly other immune modulating “calm-down” signals that interact with macrophages and DCs. Apoptotic cells also produce “find me” and “tolerate me” signals to attract and immune modulate macrophages and DCs that express specific receptors for some of these signals. Neither macrophages nor DCs are uniform, and each cell type may variably express membrane proteins that function as receptors for PtdSer or for opsonins like complement or opsonins that bind to PtdSer, such as protein S and growth arrest-specific 6. Macrophages and DCs also express scavenger receptors, CD36, and integrins that function via bridging molecules such as TSP-1 or milk fat globule-EGF factor 8 protein and that differentially engage in various multi-ligand interactions between apoptotic cells and phagocytes. In this review, we describe the anti-inflammatory and pro-homeostatic nature of apoptotic cell interaction with the immune system. We do not review some forms of immunogenic cell death. We summarize the known apoptotic cell signaling events in macrophages and DCs that are related to toll-like receptors, nuclear factor kappa B, inflammasome, the lipid

Kinetic studies of Candida parapsilosis phagocytosis by macrophages and detection of intracellular survival mechanisms

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Renata eToth

2014-11-01

Full Text Available Even though the number of Candida infections due to non-albicans species like C. parapsilosis has been increasing, little is known about their pathomechanisms. Certain aspects of C. parapsilosis and host interactions have already been investigated; however we lack information about the innate cellular responses towards this species. The aim of our project was to dissect and compare the phagocytosis of C. parapsilosis to C. albicans and to another Candida species C. glabrata by murine and human macrophages by live cell video microscopy. We broke down the phagocytic process into three stages: macrophage migration, engulfment of fungal cells and host cell killing after the uptake. Our results showed increased macrophage migration towards C. parapsilosis and we observed differences during the engulfment processes when comparing the three species. The engulfment time of C. parapsilosis was comparable to that of C. albicans regardless of the pseudohypha length and spatial orientation relative to phagocytes, while the rate of host cell killing and the overall uptake regarding C. parapsilosis showed similarities mainly with C. glabrata. Furthermore, we observed difference between human and murine phagocytes in the uptake of C. parapsilosis. UV-treatment of fungal cells had varied effects on phagocytosis dependent upon which Candida strain was used. Besides statistical analysis, live cell imaging videos showed that this species similarly to the other two also has the ability to survive in host cells via the following mechanisms: yeast replication, and pseudohypha growth inside of phagocytes, exocytosis of fungal cells and also abortion of host cell mitosis following the uptake. According to our knowledge this is the first study that provides a thorough examination of C. parapsilosis phagocytosis and reports intracellular survival mechanisms associated with this species.

Macrophage-Mediated Glial Cell Elimination in the Postnatal Mouse Cochlea

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LaShardai N. Brown

2017-12-01

Full Text Available Hearing relies on the transmission of auditory information from sensory hair cells (HCs to the brain through the auditory nerve. This relay of information requires HCs to be innervated by spiral ganglion neurons (SGNs in an exclusive manner and SGNs to be ensheathed by myelinating and non-myelinating glial cells. In the developing auditory nerve, mistargeted SGN axons are retracted or pruned and excessive cells are cleared in a process referred to as nerve refinement. Whether auditory glial cells are eliminated during auditory nerve refinement is unknown. Using early postnatal mice of either sex, we show that glial cell numbers decrease after the first postnatal week, corresponding temporally with nerve refinement in the developing auditory nerve. Additionally, expression of immune-related genes was upregulated and macrophage numbers increase in a manner coinciding with the reduction of glial cell numbers. Transient depletion of macrophages during early auditory nerve development, using transgenic CD11bDTR/EGFP mice, resulted in the appearance of excessive glial cells. Macrophage depletion caused abnormalities in myelin formation and transient edema of the stria vascularis. Macrophage-depleted mice also showed auditory function impairment that partially recovered in adulthood. These findings demonstrate that macrophages contribute to the regulation of glial cell number during postnatal development of the cochlea and that glial cells play a critical role in hearing onset and auditory nerve maturation.

Human immunodeficiency virus impairs reverse cholesterol transport from macrophages.

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Zahedi Mujawar

2006-10-01

Full Text Available Several steps of HIV-1 replication critically depend on cholesterol. HIV infection is associated with profound changes in lipid and lipoprotein metabolism and an increased risk of coronary artery disease. Whereas numerous studies have investigated the role of anti-HIV drugs in lipodystrophy and dyslipidemia, the effects of HIV infection on cellular cholesterol metabolism remain uncharacterized. Here, we demonstrate that HIV-1 impairs ATP-binding cassette transporter A1 (ABCA1-dependent cholesterol efflux from human macrophages, a condition previously shown to be highly atherogenic. In HIV-1-infected cells, this effect was mediated by Nef. Transfection of murine macrophages with Nef impaired cholesterol efflux from these cells. At least two mechanisms were found to be responsible for this phenomenon: first, HIV infection and transfection with Nef induced post-transcriptional down-regulation of ABCA1; and second, Nef caused redistribution of ABCA1 to the plasma membrane and inhibited internalization of apolipoprotein A-I. Binding of Nef to ABCA1 was required for down-regulation and redistribution of ABCA1. HIV-infected and Nef-transfected macrophages accumulated substantial amounts of lipids, thus resembling foam cells. The contribution of HIV-infected macrophages to the pathogenesis of atherosclerosis was supported by the presence of HIV-positive foam cells in atherosclerotic plaques of HIV-infected patients. Stimulation of cholesterol efflux from macrophages significantly reduced infectivity of the virions produced by these cells, and this effect correlated with a decreased amount of virion-associated cholesterol, suggesting that impairment of cholesterol efflux is essential to ensure proper cholesterol content in nascent HIV particles. These results reveal a previously unrecognized dysregulation of intracellular lipid metabolism in HIV-infected macrophages and identify Nef and ABCA1 as the key players responsible for this effect. Our findings

Biology and function of adipose tissue macrophages, dendritic cells and B cells.

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Ivanov, Stoyan; Merlin, Johanna; Lee, Man Kit Sam; Murphy, Andrew J; Guinamard, Rodolphe R

2018-04-01

The increasing incidence of obesity and its socio-economical impact is a global health issue due to its associated co-morbidities, namely diabetes and cardiovascular disease [1-5]. Obesity is characterized by an increase in adipose tissue, which promotes the recruitment of immune cells resulting in low-grade inflammation and dysfunctional metabolism. Macrophages are the most abundant immune cells in the adipose tissue of mice and humans. The adipose tissue also contains other myeloid cells (dendritic cells (DC) and neutrophils) and to a lesser extent lymphocyte populations, including T cells, B cells, Natural Killer (NK) and Natural Killer T (NKT) cells. While the majority of studies have linked adipose tissue macrophages (ATM) to the development of low-grade inflammation and co-morbidities associated with obesity, emerging evidence suggests for a role of other immune cells within the adipose tissue that may act in part by supporting macrophage homeostasis. In this review, we summarize the current knowledge of the functions ATMs, DCs and B cells possess during steady-state and obesity. Copyright © 2018 Elsevier B.V. All rights reserved.

Endogenous Murine BST-2/Tetherin Is Not a Major Restriction Factor of Influenza A Virus Infection.

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Sarah L Londrigan

Full Text Available BST-2 (tetherin, CD317, HM1.24 restricts virus growth by tethering enveloped viruses to the cell surface. The role of BST-2 during influenza A virus infection (IAV is controversial. Here, we assessed the capacity of endogenous BST-2 to restrict IAV in primary murine cells. IAV infection increased BST-2 surface expression by primary macrophages, but not alveolar epithelial cells (AEC. BST-2-deficient AEC and macrophages displayed no difference in susceptibility to IAV infection relative to wild type cells. Furthermore, BST-2 played little role in infectious IAV release from either AEC or macrophages. To examine BST-2 during IAV infection in vivo, we infected BST-2-deficient mice. No difference in weight loss or in viral loads in the lungs and/or nasal tissues were detected between BST-2-deficient and wild type animals. This study rules out a major role for endogenous BST-2 in modulating IAV in the mouse model of infection.

The in vitro effects of macrophages on the osteogenic capabilities of MC3T3-E1 cells encapsulated in a biomimetic poly(ethylene glycol) hydrogel.

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Saleh, Leila S; Carles-Carner, Maria; Bryant, Stephanie J

2018-04-15

Poly(ethylene glycol) PEG-based hydrogels are promising for cell encapsulation and tissue engineering, but are known to elicit a foreign body response (FBR) in vivo. The goal of this study was to investigate the impact of the FBR, and specifically the presence of inflammatory macrophages, on encapsulated cells and their ability to synthesize new extracellular matrix. This study employed an in vitro co-culture system with murine macrophages and MC3T3-E1 pre-osteoblasts encapsulated in a bone-mimetic hydrogel, which were cultured in transwell inserts, and exposed to an inflammatory stimulant, lipopolysaccharide (LPS). The co-culture was compared to mono-cultures of the cell-laden hydrogels alone and with LPS over 28 days. Two macrophage cell sources, RAW 264.7 and primary derived, were investigated. The presence of LPS-stimulated primary macrophages led to significant changes in the cell-laden hydrogel by a 5.3-fold increase in percent apoptotic osteoblasts at day 28, 4.2-fold decrease in alkaline phosphatase activity at day 10, and 7-fold decrease in collagen deposition. The presence of LPS-stimulated RAW macrophages led to significant changes in the cell-laden hydrogel by 5-fold decrease in alkaline phosphatase activity at day 10 and 4-fold decrease in collagen deposition. Mineralization, as measured by von Kossa stain or quantified by calcium content, was not sensitive to macrophages or LPS. Elevated interleukin-6 and tumor necrosis factor-α secretion were detected in mono-cultures with LPS and co-cultures. Overall, primary macrophages had a more severe inhibitory effect on osteoblast differentiation than the macrophage cell line, with greater apoptosis and collagen I reduction. In summary, this study highlights the detrimental effects of macrophages on encapsulated cells for bone tissue engineering. Poly(ethylene glycol) (PEG)-based hydrogels are promising for cell encapsulation and tissue engineering, but are known to elicit a foreign body response (FBR) in

Emodin Induces Apoptotic Death in Murine Myelomonocytic Leukemia WEHI-3 Cells In Vitro and Enhances Phagocytosis in Leukemia Mice In Vivo

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Yuan-Chang Chang

2011-01-01

Full Text Available Emodin is one of major compounds in rhubarb (Rheum palmatum L., a plant used as herbal medicine in Chinese population. Although many reports have shown that emodin exhibits anticancer activity in many tumor cell types, there is no available information addressing emodin-affected apoptotic responses in the murine leukemia cell line (WEHI-3 and modulation of the immune response in leukemia mice. We investigated that emodin induced cytotoxic effects in vitro and affected WEHI-3 cells in vivo. This study showed that emodin decreased viability and induced DNA fragmentation in WEHI-3 cells. Cells after exposure to emodin for 24 h have shown chromatin condensation and DNA damage. Emodin stimulated the productions of ROS and Ca2+ and reduced the level of ΔΨm by flow cytometry. Our results from Western blotting suggest that emodin triggered apoptosis of WEHI-3 cells through the endoplasmic reticulum (ER stress, caspase cascade-dependent and -independent mitochondrial pathways. In in vivo study, emodin enhanced the levels of B cells and monocytes, and it also reduced the weights of liver and spleen compared with leukemia mice. Emodin promoted phagocytic activity by monocytes and macrophages in comparison to the leukemia mice group. In conclusions, emodin induced apoptotic death in murine leukemia WEHI-3 cells and enhanced phagocytosis in the leukemia animal model.

Collagen-Induced Arthritis: A model for Murine Autoimmune Arthritis

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Pietrosimone, K. M.; Jin, M.; Poston, B.; Liu, P.

2015-01-01

Collagen-induced arthritis (CIA) is a common autoimmune animal model used to study rheumatoid arthritis (RA). The development of CIA involves infiltration of macrophages and neutrophils into the joint, as well as T and B cell responses to type II collagen. In murine CIA, genetically susceptible mice (DBA/1J) are immunized with a type II bovine collagen emulsion in complete Freund’s adjuvant (CFA), and receive a boost of type II bovine collagen in incomplete Freund’s adjuvant (IFA) 21 days aft...

From inflammation to wound healing: using a simple model to understand the functional versatility of murine macrophages.

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Childs, Lauren M; Paskow, Michael; Morris, Sidney M; Hesse, Matthias; Strogatz, Steven

2011-11-01

Macrophages are fundamental cells of the innate immune system. Their activation is essential for such distinct immune functions as inflammation (pathogen-killing) and tissue repair (wound healing). An open question has been the functional stability of an individual macrophage cell: whether it can change its functional profile between different immune responses such as between the repair pathway and the inflammatory pathway. We studied this question theoretically by constructing a rate equation model for the key substrate, enzymes and products of the pathways; we then tested the model experimentally. Both our model and experiments show that individual macrophages can switch from the repair pathway to the inflammation pathway but that the reverse switch does not occur.

T3 Regulates a Human Macrophage-Derived TSH-β Splice Variant: Implications for Human Bone Biology.

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Baliram, R; Latif, R; Morshed, S A; Zaidi, M; Davies, T F

2016-09-01

TSH and thyroid hormones (T3 and T4) are intimately involved in bone biology. We have previously reported the presence of a murine TSH-β splice variant (TSH-βv) expressed specifically in bone marrow-derived macrophages and that exerted an osteoprotective effect by inducing osteoblastogenesis. To extend this observation and its relevance to human bone biology, we set out to identify and characterize a TSH-β variant in human macrophages. Real-time PCR analyses using human TSH-β-specific primers identified a 364-bp product in macrophages, bone marrow, and peripheral blood mononuclear cells that was sequence verified and was homologous to a human TSH-βv previously reported. We then examined TSH-βv regulation using the THP-1 human monocyte cell line matured into macrophages. After 4 days, 46.1% of the THP-1 cells expressed the macrophage markers CD-14 and macrophage colony-stimulating factor and exhibited typical morphological characteristics of macrophages. Real-time PCR analyses of these cells treated in a dose-dependent manner with T3 showed a 14-fold induction of human TSH-βv mRNA and variant protein. Furthermore, these human TSH-βv-positive cells, induced by T3 exposure, had categorized into both M1 and M2 macrophage phenotypes as evidenced by the expression of macrophage colony-stimulating factor for M1 and CCL-22 for M2. These data indicate that in hyperthyroidism, bone marrow resident macrophages have the potential to exert enhanced osteoprotective effects by oversecreting human TSH-βv, which may exert its local osteoprotective role via osteoblast and osteoclast TSH receptors.

VEGF-production by CCR2-dependent macrophages contributes to laser-induced choroidal neovascularization.

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Torsten A Krause

Full Text Available Age-related macular degeneration (AMD is the most prevalent cause of blindness in the elderly, and its exsudative subtype critically depends on local production of vascular endothelial growth factor A (VEGF. Mononuclear phagocytes, such as macrophages and microglia cells, can produce VEGF. Their precursors, for example monocytes, can be recruited to sites of inflammation by the chemokine receptor CCR2, and this has been proposed to be important in AMD. To investigate the role of macrophages and CCR2 in AMD, we studied intracellular VEGF content in a laser-induced murine model of choroidal neovascularisation. To this end, we established a technique to quantify the VEGF content in cell subsets from the laser-treated retina and choroid separately. 3 days after laser, macrophage numbers and their VEGF content were substantially elevated in the choroid. Macrophage accumulation was CCR2-dependent, indicating recruitment from the circulation. In the retina, microglia cells were the main VEGF+ phagocyte type. A greater proportion of microglia cells contained VEGF after laser, and this was CCR2-independent. On day 6, VEGF-expressing macrophage numbers had already declined, whereas numbers of VEGF+ microglia cells remained increased. Other sources of VEGF detectable by flow cytometry included in dendritic cells and endothelial cells in both retina and choroid, and Müller cells/astrocytes in the retina. However, their VEGF content was not increased after laser. When we analyzed flatmounts of laser-treated eyes, CCR2-deficient mice showed reduced neovascular areas after 2 weeks, but this difference was not evident 3 weeks after laser. In summary, CCR2-dependent influx of macrophages causes a transient VEGF increase in the choroid. However, macrophages augmented choroidal neovascularization only initially, presumably because VEGF production by CCR2-independent eye cells prevailed at later time points. These findings identify macrophages as a relevant source

Thermo-responsive cell culture carrier: Effects on macrophage functionality and detachment efficiency.

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Rennert, Knut; Nitschke, Mirko; Wallert, Maria; Keune, Natalie; Raasch, Martin; Lorkowski, Stefan; Mosig, Alexander S

2017-01-01

Harvesting cultivated macrophages for tissue engineering purposes by enzymatic digestion of cell adhesion molecules can potentially result in unintended activation, altered function, or behavior of these cells. Thermo-responsive polymer is a promising tool that allows for gentle macrophage detachment without artificial activation prior to subculture within engineered tissue constructs. We therefore characterized different species of thermo-responsive polymers for their suitability as cell substrate and to mediate gentle macrophage detachment by temperature shift. Primary human monocyte- and THP-1-derived macrophages were cultured on thermo-responsive polymers and characterized for phagocytosis and cytokine secretion in response to lipopolysaccharide stimulation. We found that both cell types differentially respond in dependence of culture and stimulation on thermo-responsive polymers. In contrast to THP-1 macrophages, primary monocyte-derived macrophages showed no signs of impaired viability, artificial activation, or altered functionality due to culture on thermo-responsive polymers compared to conventional cell culture. Our study demonstrates that along with commercially available UpCell carriers, two other thermo-responsive polymers based on poly(vinyl methyl ether) blends are attractive candidates for differentiation and gentle detachment of primary monocyte-derived macrophages. In summary, we observed similar functionality and viability of primary monocyte-derived macrophages cultured on thermo-responsive polymers compared to standard cell culture surfaces. While this first generation of custom-made thermo-responsive polymers does not yet outperform standard culture approaches, our results are very promising and provide the basis for exploiting the unique advantages offered by custom-made thermo-responsive polymers to further improve macrophage culture and recovery in the future, including the covalent binding of signaling molecules and the reduction of

Piliation of Lactobacillus rhamnosus GG Promotes Adhesion, Phagocytosis, and Cytokine Modulation in Macrophages

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Vargas García, Cynthia E.; Petrova, Mariya; Claes, Ingmar J. J.; De Boeck, Ilke; Verhoeven, Tine L. A.; Dilissen, Ellen; von Ossowski, Ingemar; Palva, Airi; Bullens, Dominique M.; Vanderleyden, Jos

2015-01-01

Recently, spaCBA-encoded pili on the cell surface of Lactobacillus rhamnosus GG were identified to be key molecules for binding to human intestinal mucus and Caco-2 intestinal epithelial cells. Here, we investigated the role of the SpaCBA pilus of L. rhamnosus GG in the interaction with macrophages in vitro by comparing the wild type with surface mutants. Our results show that SpaCBA pili play a significant role in the capacity for adhesion to macrophages and also promote bacterial uptake by these phagocytic cells. Interestingly, our data suggest that SpaCBA pili also mediate anti-inflammatory effects by induction of interleukin-10 (IL-10) mRNA and reduction of interleukin-6 (IL-6) mRNA in a murine RAW 264.7 macrophage cell line. These pili appear to mediate these effects indirectly by promoting close contact with the macrophages, facilitating the exertion of anti-inflammatory effects by other surface molecules via yet unknown mechanisms. Blockage of complement receptor 3 (CR3), previously identified to be a receptor for streptococcal pili, significantly decreased the uptake of pilus-expressing strains in RAW 264.7 cells, while the expression of IL-10 and IL-6 mRNA by these macrophages was not affected by this blocking. On the other hand, blockage of Toll-like receptor 2 (TLR2) significantly reduced the expression of IL-6 mRNA irrespective of the presence of pili. PMID:25576613

Effect of Vibrio cholerae neuraminidase on the mitogen response of T lymphocytes. I. Enhancement of macrophage T-lymphocyte cooperation in concanavalin-A-induced lymphocyte activation.

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Knop, J

1980-12-01

Vibrio cholerae neuraminidase (VCN) enhances the immune response of lymphocytes in various systems, such as antigen- and mitogen-induced blastogenesis, mixed lymphocyte culture (MLC) and tumor-cell response. We used macrophage-depleted and reconstituted murine lymph-node T-cells to investigate the effect of VCN on macrophage-T-lymphocyte co-operation in Con-A-induced lymphocyte activation. In unfractionated lymph-node cells VCN enhanced the Con-A-induced lymphocyte activation as measured by 3H-thymidine (3H-dThd) incorporation. Removing macrophages from the cells resulted in a significantly diminished response. In addition the enhancing effect of VCN was greatly reduced. Reconstitution of the lymphocyte cultures with macrophages in increasing numbers and from various sources rstored the lymphocyte response and the enhancing effect of VCN. VCN proved to be most efficient in cultures reconstituted with normal peritoneal macrophages. Some effect was also observed using bone-marrow-derived (BM) macrophages. However, higher numbers of normal PE macrophages in the presence of VCN inhibited lymphocyte activation, and inhibition by thioglycollate-broth-induced macrophages was considerably increased by VCN. These results suggest that VCN acts by increasing the efficiency of macrophage-T lymphocyte interaction.

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.

β-Cypermethrin and its metabolite 3-phenoxybenzoic acid exhibit immunotoxicity in murine macrophages.

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Wang, Xia; He, Bingnan; Kong, Baida; Wei, Lai; Wang, Rong; Zhou, Chenqian; Shao, Yiyan; Lin, Jiajia; Jin, Yuanxiang; Fu, Zhengwei

2017-12-01

β-Cypermethrin (β-CYP), one of most important pyrethroids, is widely used to control insects, and has been detected in organisms, including human. Pyrethroids have been shown to pose neurotoxicity, hepatotoxicity, endocrine disruption and reproductive risks in mammals. However, research in immunotoxicity of pyrethroids, especially their metabolites, is limited. A common metabolite of pyrethroids is 3-phenoxybenzoic acid (3-PBA) in mammals. Thus, in this study, we evaluated the immunotoxicity of β-CYP and 3-PBA in mouse macrophages, RAW 264.7 cells. MTT assays showed that both β-CYP and 3-PBA reduced cell viability in a concentration- and time-dependent manner. Flow cytometry with Annexin-V/PI staining demonstrated that both β-CYP and 3-PBA induced RAW 264.7 cell apoptosis. Furthermore, our results also showed that N-acetylcysteine partially blocked β-CYP- and 3-PBA-induced cytotoxicity and apoptosis. Intrinsic apoptotic pathway was stimulated by both β-CYP and 3-PBA exposure. In addition, we found that β-CYP and 3-PBA inhibited mRNA levels of pro-inflammatory cytokines with or without LPS stimulation. Phagocytosis assay showed that both β-CYP and 3-PBA inhibited phagocytic ability of macrophages. Moreover, it was also found that both β-CYP and 3-PBA increased reactive oxygen species (ROS) levels in RAW 264.7 cells. Accordingly, both β-CYP and 3-PBA were found to regulate the mRNA levels of oxidative stress-related genes in RAW 264.7 cells. Taken together, the results obtained in this study demonstrated that β-CYP and 3-PBA may have immunotoxic effect on macrophages and that elevated ROS may underlie the mechanism. The present study will help to understand the health risks caused by β-CYP and other pyrethroids. © The Author 2017. Published by Oxford University Press on behalf of the Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences. All rights reserved. For permissions, please e

Nuclear DAMP complex-mediated RAGE-dependent macrophage cell death

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Chen, Ruochan [Department of Surgery, University of Pittsburgh, Pittsburgh, PA 15213 (United States); Department of Infectious Diseases and State Key Lab of Viral Hepatitis, Xiangya Hospital, Central South University, Changsha, Hunan 410008 (China); Fu, Sha; Fan, Xue-Gong [Department of Infectious Diseases and State Key Lab of Viral Hepatitis, Xiangya Hospital, Central South University, Changsha, Hunan 410008 (China); Lotze, Michael T.; Zeh, Herbert J. [Department of Surgery, University of Pittsburgh, Pittsburgh, PA 15213 (United States); Tang, Daolin, E-mail: tangd2@upmc.edu [Department of Surgery, University of Pittsburgh, Pittsburgh, PA 15213 (United States); Kang, Rui, E-mail: kangr@upmc.edu [Department of Surgery, University of Pittsburgh, Pittsburgh, PA 15213 (United States)

2015-03-13

High mobility group box 1 (HMGB1), histone, and DNA are essential nuclear components involved in the regulation of chromosome structure and function. In addition to their nuclear function, these molecules act as damage-associated molecular patterns (DAMPs) alone or together when released extracellularly. The synergistic effect of these nuclear DNA-HMGB1-histone complexes as DAMP complexes (nDCs) on immune cells remains largely unexplored. Here, we demonstrate that nDCs limit survival of macrophages (e.g., RAW264.7 and peritoneal macrophages) but not cancer cells (e.g., HCT116, HepG2 and Hepa1-6). nDCs promote production of inflammatory tumor necrosis factor α (TNFα) release, triggering reactive oxygen species-dependent apoptosis and necrosis. Moreover, the receptor for advanced glycation end products (RAGE), but not toll-like receptor (TLR)-4 and TLR-2, was required for Akt-dependent TNFα release and subsequent cell death following treatment with nDCs. Genetic depletion of RAGE by RNAi, antioxidant N-Acetyl-L-cysteine, and TNFα neutralizing antibody significantly attenuated nDC-induced cell death. These findings provide evidence supporting novel signaling mechanisms linking nDCs and inflammation in macrophage cell death. - Highlights: • Nuclear DAMP complexes (nDCs) selectively induce cell death in macrophages, but not cancer cells. • TNFα-mediated oxidative stress is required for nDC-induced death. • RAGE-mediated Akt activation is required for nDC-induced TNFα release. • Blocking RAGE and TNFα inhibits nDC-induced macrophage cell death.

Quercetin uptake and metabolism by murine peritoneal macrophages in vitro

Directory of Open Access Journals (Sweden)

Chieh-Jung Liu

2015-12-01

Full Text Available Quercetin (Q, a bioflavonoid ubiquitously distributed in vegetables, fruits, leaves, and grains, can be absorbed, transported, and excreted after oral intake. However, little is known about Q uptake and metabolism by macrophages. To clarify the puzzle, Q at its noncytotoxic concentration (44μM was incubated without or with mouse peritoneal macrophages for different time periods. Medium alone, extracellular, and intracellular fluids of macrophages were collected to detect changes in Q and its possible metabolites using high-performance liquid chromatography. The results showed that Q was unstable and easily oxidized in either the absence or the presence of macrophages. The remaining Q and its metabolites, including isorhamnetin and an unknown Q metabolite [possibly Q– (O-semiquinone], might be absorbed by macrophages. The percentage of maximal Q uptake by macrophages was found to be 2.28% immediately after incubation; however, Q uptake might persist for about 24 hours. Q uptake by macrophages was greater than the uptake of its methylated derivative isorhamnetin. As Q or its metabolites entered macrophages, those compounds were metabolized primarily into isorhamnetin, kaempferol, or unknown endogenous Q metabolites. The present study, which aimed to clarify cellular uptake and metabolism of Q by macrophages, may have great potential for future practical applications for human health and immunopharmacology.

HIV-1 Resistant CDK2-Knockdown Macrophage-Like Cells Generated from 293T Cell-Derived Human Induced Pluripotent Stem Cells

Directory of Open Access Journals (Sweden)

Kuan-Teh Jeang

2012-07-01

Full Text Available A major challenge in studies of human diseases involving macrophages is low yield and heterogeneity of the primary cells and limited ability of these cells for transfections and genetic manipulations. To address this issue, we developed a simple and efficient three steps method for somatic 293T cells reprogramming into monocytes and macrophage-like cells. First, 293T cells were reprogrammed into induced pluripotent stem cells (iPSCs through a transfection-mediated expression of two factors, Oct-4 and Sox2, resulting in a high yield of iPSC. Second, the obtained iPSC were differentiated into monocytes using IL-3 and M-CSF treatment. And third, monocytes were differentiated into macrophage-like cells in the presence of M-CSF. As an example, we developed HIV-1-resistant macrophage-like cells from 293T cells with knockdown of CDK2, a factor critical for HIV-1 transcription. Our study provides a proof-of-principle approach that can be used to study the role of host cell factors in HIV-1 infection of human macrophages.

Macrophage function in murine allogeneic bone marrow radiation chimeras in the early phase after transplantation

International Nuclear Information System (INIS)

Roesler, J.; Baccarini, M.; Vogt, B.; Lohmann-Matthes, M.L.

1989-01-01

We tested several of the functions of macrophages (M phi) in the early phase after allogeneic bone marrow transfer to get information about this important aspect of the nonspecific immune system in the T-cell-deficient recipient. On days 3-5 after transfer, the number of M phi was reduced in the spleen, liver, lungs, and peritoneal cavity (Pe). The phagocytosis of sheep red blood cells (SRBC) by these M phi was normal or even enhanced, as in the case of Pe-M phi. Already on days 8-12 after transfer, the number of M phi in spleen and liver exceeded that of controls, whereas the number was still reduced in lungs and Pe. We examined their ability to kill P815 tumor cells, to produce tumor necrosis factor-alpha (TNF alpha), to phagocytose SRBC, to produce reactive oxygen intermediates (ROI) in vitro and to kill Listeria monocytogenes in vivo. Most functions were normal and often even enhanced, depending on the organ origin, but the ability of Pe-M phi to produce ROI was reduced. Proliferative response to macrophage colony-stimulating factor (M-CSF) and killing of YAC-1 tumor cells revealed a high frequency of macrophage precursor cells in the spleen and liver and a high natural killer (NK) activity in the liver. Altogether, enhanced nonspecific immune function, especially preactivated M phi, may enable chimeras to survive attacks by opportunistic pathogens

Garlic (Allium sativum) stimulates lipopolysaccharide-induced tumor necrosis factor-alpha production from J774A.1 murine macrophages.

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Sung, Jessica; Harfouche, Youssef; De La Cruz, Melissa; Zamora, Martha P; Liu, Yan; Rego, James A; Buckley, Nancy E

2015-02-01

Garlic (Allium sativum) is known to have many beneficial attributes such as antimicrobial, antiatherosclerotic, antitumorigenetic, and immunomodulatory properties. In the present study, we investigated the effects of an aqueous garlic extract on macrophage cytokine production by challenging the macrophage J774A.1 cell line with the garlic extract in the absence or presence of lipopolysaccharide (LPS) under different conditions. The effect of allicin, the major component of crushed garlic, was also investigated. Using enzyme-linked immunosorbent assay and reverse transcriptase-quantitative polymerase chain reaction, it was found that garlic and synthetic allicin greatly stimulated tumor necrosis factor-alpha (TNF-α) production in macrophages treated with LPS. The TNF-α secretion levels peaked earlier and were sustained for a longer time in cells treated with garlic and LPS compared with cells treated with LPS alone. Garlic acted in a time-dependent manner. We suggest that garlic, at least partially via its allicin component, acts downstream from LPS to stimulate macrophage TNF-α secretion. © 2014 The Authors. Phytotherapy Research published by John Wiley & Sons, Ltd.

Antitumor activity of the Korean mistletoe lectin is attributed to activation of macrophages and NK cells.

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Yoon, Taek Joon; Yoo, Yung Choon; Kang, Tae Bong; Song, Seong Kyu; Lee, Kyung Bok; Her, Erk; Song, Kyung Sik; Kim, Jong Bae

2003-10-01

Inhibitory effect of the lectins (KML-C) isolated from Korean mistletoe (KM; Viscum album coloratum) on tumor metastases produced by murine tumor cells (B16-BL6 melanoma, colon 26-M3.1 carcinoma and L5178Y-ML25 lymphoma cells) was investigated in syngeneic mice. An intravenous (i.v.) administration of KML-C (20-50 ng/mouse) 2 days before tumor inoculation significantly inhibited lung metastases of both B16-BL6 and colon 26-M3.1 cells. The prophylactic effect of 50 ng/mouse of KML-C on lung metastasis was almost the same with that of 100 microg/mouse of KM. Treatment with KML-C 1 day after tumor inoculation induced a significant inhibition of not only the experimental lung metastasis induced by B16-BL6 and colon 26-M3.1 cells but also the liver and spleen metastasis of L5178Y-ML25 cells. Furthermore, multiple administration of KML-C given at 3 day-intervals after tumor inoculation led to a significant reduction of lung metastasis and suppression of the growth of B16-BL6 melanoma cells in a spontaneous metastasis model. In an assay for natural killer (NK) cell activity, i.v. administration of KML-C (50 ng/mouse) significantly augmented NK cytotoxicity against Yac-1 tumor cells 2 days after KML-C treatment. In addition, treatment with KML-C (50 ng/mouse) induced tumoricidal activity of peritoneal macrophages against B16-BL6 and 3LL cells. These results suggest that KML-C has an immunomodulating activity to enhance the host defense system against tumors, and that its prophylactic and therapeutic effect on tumor metastasis is associated with the activation of NK cells and macrophages.

Effects of interferon gamma and specific polyclonal antibody on the infection of murine peritoneal macrophages and murine macrophage cell line PMJ2-R with Encephalitozoon cuniculi

Czech Academy of Sciences Publication Activity Database

Jelínek, Jiří; Salát, Jiří; Sak, Bohumil; Kopecký, Jan

2007-01-01

Roč. 54, č. 3 (2007), s. 172-176 ISSN 0015-5683 R&D Projects: GA ČR GP524/03/D167 Institutional research plan: CEZ:AV0Z60220518 Keywords : microsporidia * Encephalitozoon cuniculi * antibody * macrophage s * interferon gamma (IFN-gamma) Subject RIV: EC - Immunology Impact factor: 1.000, year: 2007

Listeria monocytogenes infection of HD11, chicken macrophage-like cells.

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Jarvis, N A; Donaldson, J R; O'Bryan, C A; Ricke, S C; Crandall, P G

2017-04-01

Listeria monocytogenes can be carried by and infect poultry, although the clinical disease in birds is rare. Escape from macrophage phagocytosis is a key step in pathogenesis for L. monocytogenes. Therefore, we investigated the infection of the chicken macrophage-like cell line HD11 with 2 strains of L. monocytogenes EGD-e and Scott A. After infection, L. monocytogenes was quantified by spread plating and HD11 was quantified with trypan blue exclusion stain before enumeration. The standard macrophage killing protocols require washing the cell monolayers 3 times with PBS, which was found to negatively influence HD11 monolayers. Maximum bacterial densities within macrophages were not different between the 2 Listeria strains. HD11 required more than 11 h to effectively reduce intracellular L. monocytogenes Scott A, and Scott A was more susceptible to HD11 killing than EGD-e. It appears that Listeria infection initially causes attenuation of HD11 growth, and infected HD11 cells do not begin to lyse until at least 11 h post infection. These results suggest that there are subtle strain to strain differences in response to HD11 macrophage phagocytosis. The long lead-time required for HD11 to kill L. monocytogenes cells means that there is sufficient time available for chicken macrophages to circulate in the blood and transfer the intracellular Listeria to multiple tissues. © 2016 Poultry Science Association Inc.

Suppression of inflammatory reactions by terpinen-4-ol, a main constituent of tea tree oil, in a murine model of oral candidiasis and its suppressive activity to cytokine production of macrophages in vitro.

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Ninomiya, Kentaro; Hayama, Kazumi; Ishijima, Sanae A; Maruyama, Naho; Irie, Hiroshi; Kurihara, Junichi; Abe, Shigeru

2013-01-01

The onset of oral candidiasis is accompanied by inflammatory symptoms such as pain in the tongue, edema or tissue damage and lowers the quality of life (QOL) of the patient. In a murine oral candidiasis model, the effects were studied of terpinen-4-ol (T-4-ol), one of the main constituents of tea tree oil, Melaleuca alternifolia, on inflammatory reactions. When immunosuppressed mice were orally infected with Candida albicans, their tongues showed inflammatory symptoms within 24 h after the infection, which was monitored by an increase of myeloperoxidase activity and macrophage inflammatory protein-2 in their tongue homogenates. Oral treatment with 50 µL of 40 mg/mL terpinen-4-ol 3h after the Candida infection clearly suppressed the increase of these inflammatory parameters. In vitro analysis of the effects of terpinen-4-ol on cytokine secretion of macrophages indicated that 800 µg/mL of this substance significantly inhibited the cytokine production of the macrophages cultured in the presence of heat-killed C. albicans cells. Based on these findings, the role of the anti-inflammatory action of T-4-ol in its therapeutic activity against oral candidiasis was discussed.

FTY720 ameliorates murine sclerodermatous chronic graft-versus-host disease by promoting expansion of splenic regulatory cells and inhibiting immune cell infiltration into skin.

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Huu, Doanh Le; Matsushita, Takashi; Jin, Guihua; Hamaguchi, Yasuhito; Hasegawa, Minoru; Takehara, Kazuhiko; Fujimoto, Manabu

2013-06-01

Sphingosine 1-phosphate (S1P) exerts a variety of activities in immune, inflammatory, and vascular systems. S1P plays an important role in systemic sclerosis (SSc) pathogenesis. Regulation of S1P in fibrotic diseases as well as in SSc was recently reported. FTY720, an oral S1P receptor modulator, has been shown to be a useful agent for the prevention of transplant rejection and autoimmune diseases. Murine sclerodermatous chronic graft-versus-host disease (GVHD) is a model for human sclerodermatous chronic GVHD and SSc. We undertook this study to investigate the effects of FTY720 in murine sclerodermatous chronic GVHD. FTY720 was orally administered to allogeneic recipient mice from day 0 to day 20 (short-term, early-treatment group), from day 0 to day 42 (full-term, early-treatment group), or from day 22 to day 42 (delayed-treatment group) after bone marrow transplantation. Delayed administration of FTY720 attenuated, and early administration of FTY720 inhibited, the severity and fibrosis in murine sclerodermatous chronic GVHD. With early treatment, FTY720 induced expansion of splenic myeloid-derived suppressor cells, Treg cells, and Breg cells. Vascular damage in chronic GVHD was inhibited by FTY720 through down-regulating serum levels of S1P and soluble E-selectin. FTY720 inhibited infiltration of immune cells into skin. Moreover, FTY720 diminished the expression of messenger RNA for monocyte chemotactic protein 1, macrophage inflammatory protein 1α, RANTES, tumor necrosis factor α, interferon-γ, interleukin-6 (IL-6), IL-10, IL-17A, and transforming growth factor β1 in the skin. FTY720 suppressed the immune response by promoting the expansion of regulatory cells and reducing vascular damage and infiltration of immune cells into the skin. Taken together, these results have important implications for the potential use of FTY720 in the treatment of sclerodermatous chronic GVHD and SSc in humans. Copyright © 2013 by the American College of Rheumatology.

Dendritic cells that phagocytose apoptotic macrophages loaded with mycobacterial antigens activate CD8 T cells via cross-presentation

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Espinosa-Cueto, Patricia; Magallanes-Puebla, Alejandro; Castellanos, Carlos; Mancilla, Raul

2017-01-01

While homeostatic apoptosis is immunologically silent, macrophage apoptosis during Mycobacterium tuberculosis infection can potentially induce an immune response against the mycobacteria. To examine the role of dendritic cells in this response, macrophage apoptosis was induced by incubating the macrophage with cell wall extracts of mycobacteria expressing LpqH. The apoptogenic proteins of the cell wall extracts were engulfed by the macrophage and then were translocated from the cytosol to the...

Macrophage-induced cytostasis: kinetic analysis of bromodeoxyuridine-pulsed cells

International Nuclear Information System (INIS)

Stevenson, A.P.; Crissman, H.A.; Stewart, C.C.

1985-01-01

The effect of tumoricidal macrophages on the cell cycle progression of six different cell lines was studied using an anti-bromodeoxyuridine (BrdUrd) monoclonal antibody to follow the traverse of BrdUrd-labeled cells. Exponentially growing cultured mammalian cells, from six different cell lines, were prepulsed with BrdUrd before exposure to tumoricidal macrophages. The cultured cells were then analyzed as a function of time for DNA content (by propidium iodide staining) and for BrdUrd incorporation (using a fluoresceini-sothiocyanate [FITC]-conjugated anti-BrdUrd monoclonal antibody). The position of the cells in cycle and the progression of the BrdUrd-labeled cohort was followed using flow cytometry. The cell lines examined were: Colon 26; BALB/c-3T3, ST3T3 (a spontaneously transformed, tumorigenic clone of 3T3), WCHE5 (a clone of whole Chinese hamster embryo cells), RIF (a radiation-induced fibrosarcoma), and A101D (a human melanoma). The bivariate distributions showed that for all six cell lines the BrdUrd-labeled cohort in the control cultures progressed around the cell cycle during the first 12 h of culture, as the cells exponentially increased. In contrast, when each cell line was incubated with tumoricidal macrophages, the BrdUrd-labeled cohort did not progress through cell cycle but remained in S phase throughout the 12-h culture period. There was also no evidence for progression of cells out of G 1 . The data show that cells were arrested in every phase of cell cycle. This study suggests that cytostasis, as manifested by the termination of progression in all phases of the cell cycle, is a universal phenomenon induced by tumoricidal macrophages. 20 references, 4 figures

Conditioned medium from alternatively activated macrophages induce mesangial cell apoptosis via the effect of Fas

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Huang, Yuan; Luo, Fangjun; Li, Hui; Jiang, Tao; Zhang, Nong

2013-01-01

During inflammation in the glomerulus, the proliferation of myofiroblast-like mesangial cells is commonly associated with the pathological process. Macrophages play an important role in regulating the growth of resident mesangial cells in the glomeruli. Alternatively activated macrophage (M2 macrophage) is a subset of macrophages induced by IL-13/IL-4, which is shown to play a repair role in glomerulonephritis. Prompted by studies of development, we performed bone marrow derived macrophage and rat mesangial cell co-culture study. Conditioned medium from IL-4 primed M2 macrophages induced rat mesangial cell apoptosis. The pro-apoptotic effect of M2 macrophages was demonstrated by condensed nuclei stained with Hoechst 33258, increased apoptosis rates by flow cytometry analysis and enhanced caspase-3 activation by western blot. Fas protein was up-regulated in rat mesangial cells, and its neutralizing antibody ZB4 partly inhibited M2 macrophage-induced apoptosis. The up-regulated arginase-1 expression in M2 macrophage also contributed to this apoptotic effect. These results indicated that the process of apoptosis triggered by conditioned medium from M2 macrophages, at least is partly conducted through Fas in rat mesangial cells. Our findings provide compelling evidence that M2 macrophages control the growth of mesangial cells in renal inflammatory conditions. - Highlights: • Conditioned-medium from M2 macrophages induces rat mesangial cell (MsC) apoptosis. • M2 macrophage conditioned medium exerts its pro-apoptotic effects via Fas ligand. • Arginase-1 activity in M2 macrophages plays a role in inducing apoptosis in rat MsC

Conditioned medium from alternatively activated macrophages induce mesangial cell apoptosis via the effect of Fas

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Huang, Yuan; Luo, Fangjun; Li, Hui; Jiang, Tao; Zhang, Nong, E-mail: nzhang@fudan.edu.cn

2013-11-15

During inflammation in the glomerulus, the proliferation of myofiroblast-like mesangial cells is commonly associated with the pathological process. Macrophages play an important role in regulating the growth of resident mesangial cells in the glomeruli. Alternatively activated macrophage (M2 macrophage) is a subset of macrophages induced by IL-13/IL-4, which is shown to play a repair role in glomerulonephritis. Prompted by studies of development, we performed bone marrow derived macrophage and rat mesangial cell co-culture study. Conditioned medium from IL-4 primed M2 macrophages induced rat mesangial cell apoptosis. The pro-apoptotic effect of M2 macrophages was demonstrated by condensed nuclei stained with Hoechst 33258, increased apoptosis rates by flow cytometry analysis and enhanced caspase-3 activation by western blot. Fas protein was up-regulated in rat mesangial cells, and its neutralizing antibody ZB4 partly inhibited M2 macrophage-induced apoptosis. The up-regulated arginase-1 expression in M2 macrophage also contributed to this apoptotic effect. These results indicated that the process of apoptosis triggered by conditioned medium from M2 macrophages, at least is partly conducted through Fas in rat mesangial cells. Our findings provide compelling evidence that M2 macrophages control the growth of mesangial cells in renal inflammatory conditions. - Highlights: • Conditioned-medium from M2 macrophages induces rat mesangial cell (MsC) apoptosis. • M2 macrophage conditioned medium exerts its pro-apoptotic effects via Fas ligand. • Arginase-1 activity in M2 macrophages plays a role in inducing apoptosis in rat MsC.

Airway delivery of soluble factors from plastic-adherent bone marrow cells prevents murine asthma.

Science.gov (United States)

Ionescu, Lavinia I; Alphonse, Rajesh S; Arizmendi, Narcy; Morgan, Beverly; Abel, Melanie; Eaton, Farah; Duszyk, Marek; Vliagoftis, Harissios; Aprahamian, Tamar R; Walsh, Kenneth; Thébaud, Bernard

2012-02-01

Asthma affects an estimated 300 million people worldwide and accounts for 1 of 250 deaths and 15 million disability-adjusted life years lost annually. Plastic-adherent bone marrow-derived cell (BMC) administration holds therapeutic promise in regenerative medicine. However, given the low cell engraftment in target organs, including the lung, cell replacement cannot solely account for the reported therapeutic benefits. This suggests that BMCs may act by secreting soluble factors. BMCs also possess antiinflammatory and immunomodulatory properties and may therefore be beneficial for asthma. Our objective was to investigate the therapeutic potential of BMC-secreted factors in murine asthma. In a model of acute and chronic asthma, intranasal instillation of BMC conditioned medium (CdM) prevented airway hyperresponsiveness (AHR) and inflammation. In the chronic asthma model, CdM prevented airway smooth muscle thickening and peribronchial inflammation while restoring blunted salbutamol-induced bronchodilation. CdM reduced lung levels of the T(H)2 inflammatory cytokines IL-4 and IL-13 and increased levels of IL-10. CdM up-regulated an IL-10-induced and IL-10-secreting subset of T regulatory lymphocytes and promoted IL-10 expression by lung macrophages. Adiponectin (APN), an antiinflammatory adipokine found in CdM, prevented AHR, airway smooth muscle thickening, and peribronchial inflammation, whereas the effect of CdM in which APN was neutralized or from APN knock-out mice was attenuated compared with wild-type CdM. Our study provides evidence that BMC-derived soluble factors prevent murine asthma and suggests APN as one of the protective factors. Further identification of BMC-derived factors may hold promise for novel approaches in the treatment of asthma.

Combined genome-wide expression profiling and targeted RNA interference in primary mouse macrophages reveals perturbation of transcriptional networks associated with interferon signalling

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Craigon Marie

2009-08-01

Full Text Available Abstract Background Interferons (IFNs are potent antiviral cytokines capable of reprogramming the macrophage phenotype through the induction of interferon-stimulated genes (ISGs. Here we have used targeted RNA interference to suppress the expression of a number of key genes associated with IFN signalling in murine macrophages prior to stimulation with interferon-gamma. Genome-wide changes in transcript abundance caused by siRNA activity were measured using exon-level microarrays in the presence or absence of IFNγ. Results Transfection of murine bone-marrow derived macrophages (BMDMs with a non-targeting (control siRNA and 11 sequence-specific siRNAs was performed using a cationic lipid transfection reagent (Lipofectamine2000 prior to stimulation with IFNγ. Total RNA was harvested from cells and gene expression measured on Affymetrix GeneChip Mouse Exon 1.0 ST Arrays. Network-based analysis of these data revealed six siRNAs to cause a marked shift in the macrophage transcriptome in the presence or absence IFNγ. These six siRNAs targeted the Ifnb1, Irf3, Irf5, Stat1, Stat2 and Nfkb2 transcripts. The perturbation of the transcriptome by the six siRNAs was highly similar in each case and affected the expression of over 600 downstream transcripts. Regulated transcripts were clustered based on co-expression into five major groups corresponding to transcriptional networks associated with the type I and II IFN response, cell cycle regulation, and NF-KB signalling. In addition we have observed a significant non-specific immune stimulation of cells transfected with siRNA using Lipofectamine2000, suggesting use of this reagent in BMDMs, even at low concentrations, is enough to induce a type I IFN response. Conclusion Our results provide evidence that the type I IFN response in murine BMDMs is dependent on Ifnb1, Irf3, Irf5, Stat1, Stat2 and Nfkb2, and that siRNAs targeted to these genes results in perturbation of key transcriptional networks associated

The Synthetic Lignan Secoisolariciresinol Diglucoside Prevents Asbestos-Induced NLRP3 Inflammasome Activation in Murine Macrophages

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Ralph A. Pietrofesa

2017-01-01

Full Text Available Background. The interaction of asbestos with macrophages drives two key processes that are linked to malignancy: (1 the generation of reactive oxygen species (ROS/reactive nitrogen species (RNS and (2 the activation of an inflammation cascade that drives acute and chronic inflammation, with the NLRP3 inflammasome playing a key role. Synthetic secoisolariciresinol diglucoside (SDG, LGM2605, is a nontoxic lignan with anti-inflammatory and antioxidant properties and was evaluated for protection from asbestos in murine peritoneal macrophages (MF. Methods. MFs were exposed to crocidolite asbestos ± LGM2605 given 4 hours prior to exposure and evaluated at various times for NLRP3 expression, secretion of inflammasome-activated cytokines (IL-1β and IL-18, proinflammatory cytokines (IL-6, TNFα, and HMGB1, NF-κB activation, and levels of total nitrates/nitrites. Results. Asbestos induces a significant (p<0.0001 increase in the NLRP3 subunit, release of proinflammatory cytokines, NLRP3-activated cytokines, NF-κB, and levels of nitrates/nitrites. LGM2605 significantly reduced NLRP3 ranging from 40 to 81%, IL-1β by 89–96%, and TNFα by 67–78%, as well as activated NF-κB by 48-49% while decreasing levels of nitrates/nitrites by 85–93%. Conclusions. LGM2605 reduced asbestos-induced NLRP3 expression, proinflammatory cytokine release, NF-κB activation, and nitrosative stress in MFs supporting its possible use in preventing the asbestos-induced inflammatory cascade leading to malignancy.

Obligatory participation of macrophages in an angiopoietin 2-mediated cell death switch

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Rao, Sujata; Lobov, Ivan B.; Vallance, Jefferson E.; Tsujikawa, Kaoru; Shiojima, Ichiro; Akunuru, Shailaja; Walsh, Kenneth; Benjamin, Laura E.; Lang, Richard A.

2007-01-01

Macrophages have a critical function in the recognition and engulfment of dead cells. In some settings, macrophages also actively signal programmed cell death. Here we show that during developmentally scheduled vascular regression, resident macrophages are an obligatory participant in a signaling switch that favors death over survival. This switch occurs when the signaling ligand angiopoietin 2 has the dual effect of suppressing survival signaling in vascular endothelial cells (VECs) and stim...

Calcineurin Orchestrates Lateral Transfer of Aspergillus fumigatus during Macrophage Cell Death.

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Shah, Anand; Kannambath, Shichina; Herbst, Susanne; Rogers, Andrew; Soresi, Simona; Carby, Martin; Reed, Anna; Mostowy, Serge; Fisher, Matthew C; Shaunak, Sunil; Armstrong-James, Darius P

2016-11-01

Pulmonary aspergillosis is a lethal mold infection in the immunocompromised host. Understanding initial control of infection and how this is altered in the immunocompromised host are key goals for comprehension of the pathogenesis of pulmonary aspergillosis. To characterize the outcome of human macrophage infection with Aspergillus fumigatus and how this is altered in transplant recipients on calcineurin inhibitor immunosuppressants. We defined the outcome of human macrophage infection with A. fumigatus, as well as the impact of calcineurin inhibitors, through a combination of single-cell fluorescence imaging, transcriptomics, proteomics, and in vivo studies. Macrophage phagocytosis of A. fumigatus enabled control of 90% of fungal germination. However, fungal germination in the late phagosome led to macrophage necrosis. During programmed necroptosis, we observed frequent cell-cell transfer of A. fumigatus between macrophages, which assists subsequent control of germination in recipient macrophages. Lateral transfer occurred through actin-dependent exocytosis of the late endosome in a vasodilator-stimulated phosphoprotein envelope. Its relevance to the control of fungal germination was also shown by direct visualization in our zebrafish aspergillosis model in vivo. The calcineurin inhibitor FK506 (tacrolimus) reduced cell death and lateral transfer in vitro by 50%. This resulted in uncontrolled fungal germination in macrophages and also resulted in hyphal escape. These observations identify programmed, necrosis-dependent lateral transfer of A. fumigatus between macrophages as an important host strategy for controlling fungal germination. This process is critically dependent on calcineurin. Our studies provide fundamental insights into the pathogenesis of pulmonary aspergillosis in the immunocompromised host.

Protein kinase activity associated with Fcγ/sub 2a/ receptor of a murine macrophage like cell line, P388D1

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Hirata, Y.; Suzuki, T.

1987-01-01

The properties of protein kinase activity associated with Fc receptor specific for IgG/sub 2a/(Fcγ/sub 2a/R) of a murine macrophage like cell line, P388D 1 , were investigated. IgG/sub 2a/-binding protein isolated from the detergent lysate of P388D 1 cells by affinity chromatography of IgG-Sepharose was found to contain four distinct proteins of M/sub r/ 50,000, 43,000, 37,000, and 17,000, which could be autophosphorylated upon incubation with [γ- 32 P]ATP. The autophosphorylation of Fcγ/sub 2a/ receptor complex ceased when exogenous phosphate acceptors (casein or histone) were added in the reaction mixture. Phosphorylation of casein catalyzed by Fcγ/sub 2a/ receptor complex was dependent on casein concentration, increased with time or temperature, was dependent on the concentration of ATP and Mg 2+ , and was maximum at pH near 8. Casein phosphorylation was significantly inhibited by a high concentration of Mn 2+ or KCl or by a small amount of heparin and was enhanced about 2-fold by protamine. Casein kinase activity associated with Fcγ/sub 2a/ receptor used ATP as substrate with an apparent K/sub m/ of 2 μM as well as GTP with an apparent K/sub m/ of 10 μM. Prior heating (60 0 C for 15 min) or treatment with protease (trypsin or Pronase) of Fcγ/sub 2a/ receptor complex almost totally abolished casein kinase activity. Thin-layer chromatography of a partial acid hydrolysate of the phosphorylated casein showed that the site of phosphorylation is at a seryl residue. These results suggest that Fcγ 2 /sub a/ receptor forms a molecule complex with protein kinase, whose characteristics resemble those of type II casein kinase but are different from those of cyclic nucleotide dependent protein kinase or from those of C protein kinase

Lemongrass and citral effect on cytokines production by murine macrophages.

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Bachiega, Tatiana Fernanda; Sforcin, José Maurício

2011-09-01

Cymbopogon citratus (DC) Stapf (Poaceae-Gramineae), an herb commonly known as lemongrass (LG), is an important source of ethnomedicines as well as citral, the major constituent of Cymbopogon citratus, used in perfumery, cosmetic and pharmaceutical industries for controlling pathogens. Thus, the goal of this work was to analyze the effect of LG and citral on cytokines production (IL-1β, IL-6 and IL-10) in vitro, as well as before or after LPS incubation. Peritoneal macrophages from BALB/c mice were treated with LG or citral in different concentrations for 24h. The concentrations that inhibited cytokines production were tested before or after macrophages challenge with LPS, in order to evaluate a possible anti-inflammatory action. Supernatants of cell cultures were used for cytokines determination by ELISA. As to IL-1β, only citral inhibited its release, exerting an efficient action before LPS challenge. LG and citral inhibited IL-6 release. Cymbopogon citratus showed inhibitory effects only after LPS challenge, whereas citral prevented efficiently LPS effects before and after LPS addition. Citral inhibited IL-10 production and although LG did not inhibit its production, the concentration of 100 μg/well was tested in the LPS-challenge protocol, because it inhibited IL-6 production. LG inhibited LPS action after macrophages incubation with LPS, while citral counteracted LPS action when added before or after LPS incubation. LG exerted an anti-inflammatory action and citral may be involved in its inhibitory effects on cytokines production. We suggest that a possible mechanism involved in such results could be the inhibition of the transcription factor NF-κB. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

Baicalein induces cell death in murine T cell lymphoma via inhibition of thioredoxin system.

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Patwardhan, Raghavendra S; Pal, Debojyoti; Checker, Rahul; Sharma, Deepak; Sandur, Santosh K

2017-10-01

We have earlier demonstrated the radioprotective potential of baicalein using murine splenic lymphocytes. Here, we have studied the effect of baicalein on murine T cell lymphoma EL4 cells and investigated the underlying mechanism of action. We observed that baicalein induced a dose dependent cell death in EL4 cells in vitro and significantly reduced the frequency of cancer stem cells. Previously, we have reported that murine and human T cell lymphoma cells have increased oxidative stress tolerance capacity due to active thioredoxin system. Hence, we monitored the effect of baicalein on thioredoxin system in EL4 cells. Docking studies revealed that baicalein could bind to the active site of thioredoxin reductase. Baicalein treatment led to significant reduction in the activity of thioredoxin reductase and nuclear levels of thioredoxin-1 thereby increasing ASK1 levels and caspase-3 activity. Interestingly, CRISPR-Cas9 based knock-out of ASK1 or over-expression of thioredoxin-1 abolished anti-tumor effects of baicalein in EL4 cells. Further, baicalein administration significantly reduced intra-peritoneal tumor burden of EL4 cells in C57BL/6 mice. Thus, our study describes anti-tumor effects of baicalein in EL4 cells via inhibition of thioredoxin system. Copyright © 2017 Elsevier Ltd. All rights reserved.

Signaling profiling at the single-cell level identifies a distinct signaling signature in murine hematopoietic stem cells.

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Du, Juan; Wang, Jinyong; Kong, Guangyao; Jiang, Jing; Zhang, Jingfang; Liu, Yangang; Tong, Wei; Zhang, Jing

2012-07-01

Hematopoietic stem cell (HSC) function is tightly regulated by cytokine signaling. Although phospho-flow cytometry allows us to study signaling in defined populations of cells, there has been tremendous hurdle to carry out this study in rare HSCs due to unrecoverable critical HSC markers, low HSC number, and poor cell recovery rate. Here, we overcame these difficulties and developed a "HSC phospho-flow" method to analyze cytokine signaling in murine HSCs at the single-cell level and compare HSC signaling profile to that of multipotent progenitors (MPPs), a cell type immediately downstream of HSCs, and commonly used Lin(-) cKit(+) cells (LK cells, enriched for myeloid progenitors). We chose to study signaling evoked from three representative cytokines, stem cell factor (SCF) and thrombopoietin (TPO) that are essential for HSC function and granulocyte macrophage-colony-stimulating factor (GM-CSF) that is dispensable for HSCs. HSCs display a distinct TPO and GM-CSF signaling signature from MPPs and LK cells, which highly correlates with receptor surface expression. In contrast, although majority of LK cells express lower levels of cKit than HSCs and MPPs, SCF-evoked ERK1/2 activation in LK cells shows a significantly increased magnitude for a prolonged period. These results suggest that specific cellular context plays a more important role than receptor surface expression in SCF signaling. Our study of HSC signaling at the homeostasis stage paves the way to investigate signaling changes in HSCs under conditions of stress, aging, and hematopoietic diseases. Copyright © 2012 AlphaMed Press.

Carbon monoxide-releasing molecule-3 suppresses Prevotella intermedia lipopolysaccharide-induced production of nitric oxide and interleukin-1β in murine macrophages.

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Choi, Eun-Young; Choe, So-Hui; Hyeon, Jin-Yi; Choi, Jeom-Il; Choi, In Soon; Kim, Sung-Jo

2015-10-05

This study was performed to analyze the effect of carbon monoxide (CO)-releasing molecule-3 (CORM-3) in alleviating the production of proinflammatory mediators in macrophages treated with lipopolysaccharide (LPS) from Prevotella intermedia, a pathogen associated with periodontal disease, and its possible mechanisms of action. LPS was isolated using the hot phenol-water method. Culture supernatants were assayed for nitric oxide (NO) and interleukin-1β (IL-1β). Gene expression was quantified by real-time PCR, and protein expression by immunoblotting. DNA-binding activities of NF-κB subunits were determined using an ELISA-based kit. CORM-3 suppressed the production of inducible NO synthase (iNOS)-derived NO and IL-1β at both gene transcription and translation levels in P. intermedia LPS-activated RAW264.7 cells. CORM-3 enhanced heme oxygenase-1 (HO-1) expression in cells stimulated with P. intermedia LPS, and inhibition of HO-1 activity by SnPP notably reversed the suppressive effect of CORM-3 on LPS-induced production of NO. LPS-induced phosphorylation of p38 and JNK was not affected by CORM-3. CORM-3 did not influence P. intermedia LPS-induced degradation of IκB-α. Instead, nuclear translocation of NF-κB p65 and p50 subunits was blocked by CORM-3 in LPS-treated cells. In addition, CORM-3 reduced LPS-induced p65 and p50 binding to DNA. Besides, CORM-3 significantly suppressed P. intermedia LPS-induced phosphorylation of STAT1. Overall, this study indicates that CORM-3 suppresses the production of NO and IL-1β in P. intermedia LPS-activated murine macrophages via HO-1 induction and inhibition of NF-κB and STAT1 pathways. The modulation of host inflammatory response by CORM-3 would be an attractive therapeutic approach to attenuate the progression of periodontal disease. Copyright © 2015 Elsevier B.V. All rights reserved.

Changes in lymphocyte and macrophage subsets due to morphine and ethanol treatment during a retrovirus infection causing murine AIDS

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Watson, R.R.; Prabhala, R.H.; Darban, H.R.; Yahya, M.D.; Smith, T.L.

1988-01-01

The number of lymphocytes of various subsets were not significantly changed by the ethanol exposure except those showing activation markers which were reduced. The percentage of peripheral blood cells showing markers for macrophage functions and their activation were significantly reduced after binge use of ethanol. Ethanol retarded suppression of cells by retroviral infection. However by 25 weeks of infection there was a 8.6% survival in the ethanol fed mice infected with retrovirus which was much less than virally infected controls. Morphine treatment also increased the percentage of cells with markers for macrophages and activated macrophages in virally infected mice, while suppressing them in uninfected mice. The second and third morphine injection series suppressed lymphocyte T-helper and T-suppressor cells, but not total T cells. However, suppression by morphine was significantly less during retroviral disease than suppression caused by the virus only. At 25 weeks of infection 44.8% of morphine treated, infected mice survived.

Activated macrophages create lineage-specific microenvironments for pancreatic acinar- and β-cell regeneration in mice.

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Criscimanna, Angela; Coudriet, Gina M; Gittes, George K; Piganelli, Jon D; Esni, Farzad

2014-11-01

Although the cells that contribute to pancreatic regeneration have been widely studied, little is known about the mediators of this process. During tissue regeneration, infiltrating macrophages debride the site of injury and coordinate the repair response. We investigated the role of macrophages in pancreatic regeneration in mice. We used a saporin-conjugated antibody against CD11b to reduce the number of macrophages in mice following diphtheria toxin receptor-mediated cell ablation of pancreatic cells, and evaluated the effects on pancreatic regeneration. We analyzed expression patterns of infiltrating macrophages after cell-specific injury or from the pancreas of nonobese diabetic mice. We developed an in vitro culture system to study the ability of macrophages to induce cell-specific regeneration. Depletion of macrophages impaired pancreatic regeneration. Macrophage polarization, as assessed by expression of tumor necrosis factor-α, interleukin 6, interleukin 10, and CD206, depended on the type of injury. The signals provided by polarized macrophages promoted lineage-specific generation of acinar or endocrine cells. Macrophage from nonobese diabetic mice failed to provide signals necessary for β-cell generation. Macrophages produce cell type-specific signals required for pancreatic regeneration in mice. Additional study of these processes and signals might lead to new approaches for treating type 1 diabetes or pancreatitis. Copyright © 2014 AGA Institute. Published by Elsevier Inc. All rights reserved.

Protein tyrosine phosphatase 1B deficiency ameliorates murine experimental colitis via the expansion of myeloid-derived suppressor cells.

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Jing Zhang

Full Text Available Protein tyrosine phosphatase 1B (PTP1B is a key molecule in modulating low-degree inflammatory conditions such as diabetes. The role of PTP1B in other chronic inflammations, however, remains unknown. Here, we report that PTP1B deficiency ameliorates Dextran Sulfate Sodium (DSS-induced murine experimental colitis via expanding CD11b(+Gr-1(+ myeloid-derived suppressor cells (MDSCs. Employing DSS-induced murine experimental colitis as inflammatory animal model, we found that, compared with wild-type littermates, PTP1B-null mice demonstrated greater resistance to DSS-induced colitis, as reflected by slower weight-loss, greater survival rates and decreased PMN and macrophage infiltration into the colon. The evidence collectively also demonstrated that the resistance of PTP1B-null mice to DSS-induced colitis is based on the expansion of MDSCs. First, PTP1B-null mice exhibited a greater frequency of MDSCs in the bone marrow (BM, peripheral blood and spleen when compared with wild-type littermates. Second, PTP1B levels in BM leukocytes were significantly decreased after cells were induced into MDSCs by IL-6 and GM-CSF, and the MDSC induction occurred more rapidly in PTP1B-null mice than in wild-type littermates, suggesting PTP1B as a negative regulator of MDSCs. Third, the adoptive transfer of MDSCs into mice with DSS-colitis significantly attenuated colitis, which accompanies with a decreased serum IL-17 level. Finally, PTP1B deficiency increased the frequency of MDSCs from BM cells likely through enhancing the activities of signal transducer and activator of transcription 3 (STAT3 and Janus kinase 2 (JAK2. In conclusion, our study provides the first evidences that PTP1B deficiency ameliorates murine experimental colitis via expanding MDSCs.

Macrophages loaded with gold nanoshells for photothermal ablation of glioma: An in vitro model

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Makkouk, Amani Riad

The current median survival of patients with glioblastoma multiforme (GBM), the most common type of glioma, remains at 14.6 months despite multimodal treatments (surgery, radiotherapy and chemotherapy). This research aims to study the feasibility of photothermal ablation of glioma using gold nanoshells that are heated upon laser irradiation at their resonance wavelength. The novelty of our approach lies in improving nanoshell tumor delivery by loading them in macrophages, which are known to be recruited to gliomas via tumor-released chemoattractive agents. Ferumoxides, superparamagnetic iron oxide (SPIO) nanoparticles, are needed as an additional macrophage load in order to visualize macrophage accumulation in the tumor with magnetic resonance imaging (MRI) prior to laser irradiation. The feasibility of this approach was studied in an in vitro model of glioma spheroids with the use of continuous wave (CW) laser light for ablation. The optimal loading of both murine and rat macrophages with Ferumoxides was determined using inductively coupled plasma atomic emission spectroscopy (ICP-AES). Higher concentrations of SPIO were observed in rat macrophages, and the optimal concentration was chosen at 100 microg Fe/ml. Macrophages were found to be very sensitive to near infra-red (NIR) laser irradiation, and their use as vehicles was thus not expected to hinder the function of loaded nanoshells as tumor-ablating tools. The intracellular presence of gold nanoshells in macrophages was confirmed with TEM imaging. Next, the loading of both murine and rat macrophages with gold nanoshells was studied using UV/Vis spectrophotometry, where higher nanoshell uptake was found in rat macrophages. Incubation of loaded murine and rat macrophages with rat C-6 and human ACBT spheroids, respectively, resulted in their infiltration of the spheroids. Subsequent laser irradiation at 55 W/cm2 for 10 min and follow-up of spheroid average diameter size over 14 days post-irradiation showed that

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.

Thrombopoietin inhibits murine mast cell differentiation

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Martelli, Fabrizio; Ghinassi, Barbara; Lorenzini, Rodolfo; Vannucchi, Alessandro M; Rana, Rosa Alba; Nishikawa, Mitsuo; Partamian, Sandra; Migliaccio, Giovanni; Migliaccio, Anna Rita

2009-01-01

We have recently shown that Mpl, the thrombopoietin receptor, is expressed on murine mast cells and on their precursors and that targeted deletion of the Mpl gene increases mast cell differentiation in mice. Here we report that treatment of mice with thrombopoietin, or addition of this growth factor to bone marrow-derived mast cell cultures, severely hampers the generation of mature cells from their precursors by inducing apoptosis. Analysis of the expression profiling of mast cells obtained in the presence of thrombopoietin suggests that thrombopoietin induces apoptosis of mast cells by reducing expression of the transcription factor Mitf and its target anti-apoptotic gene Bcl2. PMID:18276801

Particle Size-Dependent Antibacterial Activity and Murine Cell Cytotoxicity Induced by Graphene Oxide Nanomaterials

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Lin Zhao

2016-01-01

Full Text Available Recent studies have indicated that graphene and its derivative graphene oxide (GO engage in a wide range of antibacterial activities with limited toxicity to human cells. Here, we systematically evaluate the dependence of GO toxicity on the size of the nanoparticles used in treatments: we compare the cytotoxic effects of graphene quantum dots (GQDs, <15 nm, small GOs (SGOs, 50–200 nm, and large GOs (LGOs, 0.5–3 μm. We synthesize the results of bacterial colony count assays and SEM-based observations of morphological changes to assess the antibacterial properties that these GOs bring into effect against E. coli. We also use Live/Dead assays and morphological analysis to investigate changes to mammalian (Murine macrophage-like Raw 264.7 cells induced by the presence of the various GO particle types. Our results demonstrate that LGOs, SGOs, and GQDs possess antibacterial activities and cause mammalian cell cytotoxicity at descending levels of potency. Placing our observations in the context of previous simulation results, we suggest that both the lateral size and surface area of GO particles contribute to cytotoxic effects. We hope that the size dependence elucidated here provides a useful schematic for tuning GO-cell interactions in biomedical applications.

Chitosan drives anti-inflammatory macrophage polarisation and pro-inflammatory dendritic cell stimulation

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MI Oliveira

2012-07-01

Full Text Available Macrophages and dendritic cells (DC share the same precursor and play key roles in immunity. Modulation of their behaviour to achieve an optimal host response towards an implanted device is still a challenge. Here we compare the differentiation process and polarisation of these related cell populations and show that they exhibit different responses to chitosan (Ch, with human monocyte-derived macrophages polarising towards an anti-inflammatory phenotype while their DC counterparts display pro-inflammatory features. Macrophages and DC, whose interactions with biomaterials are frequently analysed using fully differentiated cells, were cultured directly on Ch films, rather than exposed to the polymer after complete differentiation. Ch was the sole stimulating factor and activated both macrophages and DC, without leading to significant T cell proliferation. After 10 d on Ch, macrophages significantly down-regulated expression of pro-inflammatory markers, CD86 and MHCII. Production of pro-inflammatory cytokines, particularly TNF-α, decreased with time for cells cultured on Ch, while anti-inflammatory IL-10 and TGF-β1, significantly increased. Altogether, these results suggest an M2c polarisation. Also, macrophage matrix metalloproteinase activity was augmented and cell motility was stimulated by Ch. Conversely, DC significantly enhanced CD86 expression, reduced IL-10 secretion and increased TNF-α and IL-1β levels. Our findings indicate that cells with a common precursor may display different responses, when challenged by the same biomaterial. Moreover, they help to further comprehend macrophage/DC interactions with Ch and the balance between pro- and anti-inflammatory signals associated with implant biomaterials. We propose that an overall pro-inflammatory reaction may hide the expression of anti-inflammatory cytokines, likely relevant for tissue repair/regeneration.

M1 and M2 macrophages derived from THP-1 cells differentially modulate the response of cancer cells to etoposide

International Nuclear Information System (INIS)

Genin, Marie; Clement, Francois; Fattaccioli, Antoine; Raes, Martine; Michiels, Carine

2015-01-01

Tumor associated macrophages (TAMs) are present in high density in solid tumors. TAMs share many characteristics with alternatively activated macrophages, also called M2. They have been shown to favor tumor development and a role in chemoresistance has also been suggested. Here, we investigated the effects of M2 in comparison to M1 macrophages on cancer cell sensitivity to etoposide. We set up a model of macrophage polarization, starting from THP-1 monocytes differentiated into macrophages using PMA (Phorbol 12-myristate 13-acetate). Once differentiated (M0 macrophages), they were incubated with IL-4 and IL-13 in order to obtain M2 polarized macrophages or with IFN-gamma and LPS for classical macrophage activation (M1). To mimic the communication between cancer cells and TAMs, M0, M1 or M2 macrophages and HepG2 or A549 cancer cells were co-cultured during respectively 16 (HepG2) or 24 (A549) hours, before etoposide exposure for 24 (HepG2) or 16 (A549) hours. After the incubation, the impact of etoposide on macrophage polarization was studied and cancer cell apoptosis was assessed by western-blot for cleaved caspase-3 and cleaved PARP-1 protein, caspase activity assay and FACS analysis of Annexin V and PI staining. mRNA and protein expression of M1 and M2 markers confirmed the polarization of THP-1-derived macrophages, which provide a new, easy and well-characterized model of polarized human macrophages. Etoposide-induced cancer cell apoptosis was markedly reduced in the presence of THP-1 M2 macrophages, while apoptosis was increased in cells co-cultured with M1 macrophages. On the other hand, etoposide did not influence M1 or M2 polarization. These results evidence for the first time a clear protective effect of M2 on the contrary to M1 macrophages on etoposide-induced cancer cell apoptosis

Polyethylene and methyl methacrylate particle-stimulated inflammatory tissue and macrophages up-regulate bone resorption in a murine neonatal calvaria in vitro organ system.

Science.gov (United States)

Ren, Weiping; Wu, Bin; Mayton, Lois; Wooley, Paul H

2002-09-01

There is considerable evidence that orthopaedic wear debris plays a crucial role in the pathology of aseptic loosening of joint prostheses. This study examined the effect of inflammatory membranes stimulated with methyl methacrylate and polyethylene on bone resorption, using the murine air pouch model. The capacity of RAW 264.7 mouse macrophages exposed to polymer particles to produce factors affecting bone metabolism was also studied. Neonatal calvaria bones were co-cultured with either pouch membranes or conditioned media from activated macrophages. Bone resorption was measured by the release of calcium from cultured bones, and the activity of tartrate-resistant acid phosphatase in both bone sections and culture medium was also assayed. Results showed that inflammatory pouch membrane activated by methyl methacrylate and polyethylene enhanced osteoclastic bone resorption. Conditioned media from particles stimulated mouse macrophages also stimulated bone resorption, although this effect was weaker than resorption induced by inflammatory pouch membranes. The addition of the particles directly into the medium of cultured calvaria bones had little effect on bone resorption. Our observations indicate that both inflammatory tissue and macrophages provoked by particles can stimulate bone resorption in cultured mouse neonatal calvaria bones. This simple in vitro bone resorption system allows us to investigate the fundamental cellular and molecular mechanism of wear debris induced bone resorption and to screen potential therapeutic approaches for aseptic loosening.

Oxidized LDL Induces Alternative Macrophage Phenotype through Activation of CD36 and PAFR

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Francisco J. Rios

2013-01-01

Full Text Available OxLDL is recognized by macrophage scavenger receptors, including CD36; we have recently found that Platelet-Activating Factor Receptor (PAFR is also involved. Since PAFR in macrophages is associated with suppressor function, we examined the effect of oxLDL on macrophage phenotype. It was found that the presence of oxLDL during macrophage differentiation induced high mRNA levels to IL-10, mannose receptor, PPARγ and arginase-1 and low levels of IL-12 and iNOS. When human THP-1 macrophages were pre-treated with oxLDL then stimulated with LPS, the production of IL-10 and TGF-β significantly increased, whereas that of IL-6 and IL-8 decreased. In murine TG-elicited macrophages, this protocol significantly reduced NO, iNOS and COX2 expression. Thus, oxLDL induced macrophage differentiation and activation towards the alternatively activated M2-phenotype. In murine macrophages, oxLDL induced TGF-β, arginase-1 and IL-10 mRNA expression, which were significantly reduced by pre-treatment with PAFR antagonists (WEB and CV or with antibodies to CD36. The mRNA expression of IL-12, RANTES and CXCL2 were not affected. We showed that this profile of macrophage activation is dependent on the engagement of both CD36 and PAFR. We conclude that oxLDL induces alternative macrophage activation by mechanisms involving CD36 and PAFR.

Dose-dependent cytotoxicity of clinically relevant cobalt nanoparticles and ions on macrophages in vitro

Energy Technology Data Exchange (ETDEWEB)

Kwon, Young-Min; Xia Zhidao; Glyn-Jones, Sion; Beard, David; Gill, Harinderjit S; Murray, David W, E-mail: young-min.kwon@ndos.ox.ac.u [Nuffield Department of Orthopaedic Surgery, University of Oxford, Oxford OX3 7LD (United Kingdom)

2009-04-15

Despite the satisfactory short-term implant survivorship of metal-on-metal hip resurfacing arthroplasty, periprosthetic soft-tissue masses such as pseudotumours are being increasingly reported. Cytotoxic effects of cobalt or chromium have been suggested to play a role in its aetiology. The aim of this study was to investigate the effects of clinically relevant metal nanoparticles and ions on the viability of macrophages in vitro. A RAW 264.7 murine macrophage cell line was cultured in the presence of either: (1) cobalt, chromium and titanium nanoparticles sized 30-35 nm; or (2) cobalt sulphate and chromium chloride. Two methods were used to quantify cell viability: Alamar Blue assay and Live/Dead assay. The cytotoxicity was observed only with cobalt. Cobalt nanoparticles and ions demonstrated dose-dependent cytotoxic effects on macrophages in vitro: the cytotoxic concentrations of nanoparticles and ions were 1 x 10{sup 12} particles ml{sup -1} and 1000 {mu}M, respectively. The high concentration of cobalt nanoparticles required for cytotoxicity of macrophages in vitro suggests that increased production of cobalt nanoparticles in vivo, due to excessive MoM implant wear, may lead to local adverse biological effects. Therefore, cytotoxicity of high concentrations of metal nanoparticles phagocytosed by macrophages located in the periprosthetic tissues may be an important factor in pathogenesis of pseudotumours.

Heterogeneity of the radiosensitivity and origins of tissue macrophage colony-forming cells

Energy Technology Data Exchange (ETDEWEB)

Oghiso, Yoichi; Yamada, Yutaka (National Inst. of Radiological Sciences, Chiba (Japan))

1992-12-01

Previous studies suggest that the radiosensitivity and origin of tissue macrophage precursors differ from those of hemopoietic macrophage colony-forming units (CFU-Ms) committed to macrophage-lineage cells. We assessed the origins of tissue macrophage colony-forming cells (M-CFCs) in mice by comparing their kinetics and radiosensitivities in the normal steady state and under the conditions of bone marrow depletion by [sup 89]Sr-administration and/or splenectomy. The results indicate that the radiosensitive peritoneal M-CFCs elicited by thioglycollate are derived from bone marrow macrophage precursors; where as alveolar M-CFCs, which are radioresistant, are self-sustained locally and independent of hemopoietic macrophage precursors. In contrast, highly radiosensitive liver M-CFCs are probably derived from CFU-Ms that appear to be propagated in the spleen in association with hemopoietic responses. (author).

Macrophages and mast cells in dystrophic masseter muscle: a light and electron microscopic study

DEFF Research Database (Denmark)

Kirkeby, S; Mikkelsen, H

1988-01-01

Macrophages and mast cells in masseter muscle from normal and dystrophic mice were studied by light and electron microscopy. Acid phosphatase activity and FITC-dextran were used to identify and describe macrophages. Toluidine blue was used as a marker for mast cells. In dystrophic muscle, the num......Macrophages and mast cells in masseter muscle from normal and dystrophic mice were studied by light and electron microscopy. Acid phosphatase activity and FITC-dextran were used to identify and describe macrophages. Toluidine blue was used as a marker for mast cells. In dystrophic muscle...

Thermal sensitivity and thermally enhanced radiosensitivity of murine bone marrow granulocyte-macrophage colony-forming units (CFU-GM)

International Nuclear Information System (INIS)

Yoshida, Hiroshi

1994-01-01

This study was to evaluate thermal response of granulocyte-macrophage colony-forming unit (CFU-GM) in vitro and to investigate the difference of thermally enhanced radiosensitivity on cell survivals of CFU-GM between in vitro and in vivo. In in vitro heating exposure, bone marrow suspensions, obtained from mouse femora or tibiae, were incubated; and in vivo heating exposure, the lower half-body of mice were immersed in a circulating hot water bath. For irradiation schedules, cell suspensions were irradiated in vitro or in vivo (whole-body irradiation). Thermal sensitivity curve, obtained by in vivo heating exposure, showed a shoulder region at short exposures followed by an exponential decline during longer heating exposures. The Arrhenius curve showed a break at 42.3deg C and inactivation enthalpy was 1836 kJ/mol (438 kcal/mole) below the break point and 704 kJ/mole (168 kcal/mole) above the point. When bone marrow suspensions, obtained after either in vitro or in vivo irradiation, were heated in vitro at 42deg C for 60 min, supura-additive effect on cell survivals was observed by in vivo irradiation, but not observed by in vitro irradiation. Thermal enhancement ratio (TER), defined as D 0 of combined in vivo irradiation and in vitro heating divided by D 0 of the sole in vivo irradiation, was 1.12. In vivo heating following in vivo irradiation also showed supra-additive effect, giving TER of 1.66. These findings indicated that murine marrow CFU-GM is sensitive to hyperthermia and that thermal radiosensitization is never negligible when hyperthermia is employed with preceding X-irradiation. Thus, combined use of radiotherapy and hyperthermia may decrease bone marrow function. (N.K.)

Identification and characterization of monoclonal antibodies specific for macrophages at intermediate stages in the tumoricidal activation pathway

International Nuclear Information System (INIS)

Paulnock, D.M.; Lambert, L.E.

1990-01-01

Macrophage activation for tumor cell killing is a multistep pathway in which responsive macrophages interact sequentially with priming and triggering stimuli in the acquisition of full tumoricidal activity. A number of mediators have been identified which have activating capability, including in particular IFN-gamma and bacterial LPS. Although the synergistic functional response of normal macrophages to sequential incubation with these activation signals has been well-established, characterization of the intermediate stages in the activation pathway has been difficult. We have developed a model system for examination of various aspects of macrophage activation, through the use of the murine macrophage tumor cell line, RAW 264.7. These cells, like normal macrophages, exhibit a strict requirement for interaction with both IFN-gamma and LPS in the development of tumor cytolytic activity. In addition, these cells can be stably primed by the administration of gamma-radiation. In the studies reported here, we have used RAW 264.7 cells treated with IFN-gamma alone or with IFN-gamma plus LPS to stimulate the production of rat mAb probes recognizing cell surface changes occurring during the activation process. In this way we have identified three Ag associated with intermediate stages of the activation process. One Ag, TM-1, is expressed on RAW 264.7 cells primed by IFN-gamma or gamma-radiation. This surface Ag thus identifies cells at the primed cell intermediate stage of the tumoricidal activation pathway regardless of the mechanism of activation. A second Ag, TM-2, is expressed on IFN-treated RAW 264.7 cells but not on RAW 264.7 cells primed with gamma-radiation alone. Expression of this Ag can be induced by treatment of irradiated cells with IFN-gamma, but is not induced by IFN-gamma treatment of a noncytolytic cell line, WEHI-3

Macrophage-independent T cell infiltration to the site of injury-induced brain inflammation

DEFF Research Database (Denmark)

Fux, Michaela; van Rooijen, Nico; Owens, Trevor

2008-01-01

We have addressed the role of macrophages in glial response and T cell entry to the CNS after axonal injury, by using intravenous injection of clodronate-loaded mannosylated liposomes, in C57BL6 mice. As expected, clodronate-liposome treatment resulted in depletion of peripheral macrophages which...... delay in the expansion of CD45(dim) CD11b(+) microglia in clodronate-liposome treated mice, but macrophage depletion had no effect on the percentage of infiltrating T cells in the lesion-reactive hippocampus. Lesion-induced TNFalpha mRNA expression was not affected by macrophage depletion, suggesting...... that activated glial cells are the primary source of this cytokine in the axonal injury-reactive brain. This identifies a potentially important distinction from inflammatory autoimmune infiltration in EAE, where macrophages are a prominent source of TNFalpha and their depletion prevents parenchymal T cell...

The Effect of Interferon-γ and Lipopolysaccharide on the Growth of Francisella tularensis LVS in Murine Macrophage-like Cell Line J774

Directory of Open Access Journals (Sweden)

Monika Holická

2009-01-01

Full Text Available Background: Francisella tularensis, a causative agent of human tularemia, displaying the ability to proliferate inside the human cells. Aims: To evaluate the growth potential of F. tularensis LVS strain in macrophage-like cell line J774 modulated by recombinant interferon γ and E. coli derived lipopolysaccharide. Results: Stimulation of J774 cells either by interferon-γ or lipopolysaccharide alone, or especially in combination before infection F. tularensis, revealed protective effects. Higher concentrations of stimulating agents were needed to inhibit ongoing F. tularensis infection. Conclusions: Stimulation of J774 cell line by combination of interferon-γ with lipopolysaccharide inhibits the intracellular growth of F. tularensis.

Streptococcus sanguinis induces foam cell formation and cell death of macrophages in association with production of reactive oxygen species.

Science.gov (United States)

Okahashi, Nobuo; Okinaga, Toshinori; Sakurai, Atsuo; Terao, Yutaka; Nakata, Masanobu; Nakashima, Keisuke; Shintani, Seikou; Kawabata, Shigetada; Ooshima, Takashi; Nishihara, Tatsuji

2011-10-01

Streptococcus sanguinis, a normal inhabitant of the human oral cavity, is a common streptococcal species implicated in infective endocarditis. Herein, we investigated the effects of infection with S. sanguinis on foam cell formation and cell death of macrophages. Infection with S. sanguinis stimulated foam cell formation of THP-1, a human macrophage cell line. At a multiplicity of infection >100, S. sanguinis-induced cell death of the macrophages. Viable bacterial infection was required to trigger cell death because heat-inactivated S. sanguinis did not induce cell death. The production of cytokines interleukin-1β and tumor necrosis factor-α from macrophages was also stimulated during bacterial infection. Inhibition of the production of reactive oxygen species (ROS) resulted in reduced cell death, suggesting an association of ROS with cell death. Furthermore, S. sanguinis-induced cell death appeared to be independent of activation of inflammasomes, because cleavage of procaspase-1 was not evident in infected macrophages. © 2011 Federation of European Microbiological Societies. Published by Blackwell Publishing Ltd. All rights reserved.

Phagocytosis and immune response studies of Macrophage-Nanodiamond Interactions in vitro and in vivo.

Science.gov (United States)

Huang, K-J; Lee, C-Y; Lin, Y-C; Lin, C-Y; Perevedentseva, E; Hung, S-F; Cheng, C-L

2017-10-01

The applications of nanodiamond as drug delivery and bio-imaging can require the relinquishing ND-drug conjugate via blood flow, where interaction with immune cells may occur. In this work, we investigated the ND penetration in macrophage and the immune response using the tissue-resident murine macrophages (RAW 264.7). Confocal fluorescence imaging, immunofluorescence analysis of nuclear translocation of interferon regulatory factor IRF-3 and transcriptional factor NF-κΒ, analysis of pro-inflammatory cytokines production IL-1β, IL-6 IL-10 with a reverse transcription-polymerase chain reaction technique were applied. The TNF-α factor production has been studied both in vitro at ND interaction with the macrophage and in vivo after ND injection in the mice blood system using immunoassay. The macrophage antibacterial function was estimated through E. coli bacterial colony formation. ND didn't stimulate the immune response and functionality of the macrophage was not altered. Using MTT test, ND was found negligibly cytotoxic to macrophages. Thus, ND can serve as a biocompatible platform for bio-medical applications. Left: Graphic representation of Nanodiamond internalization in macrophage. Right: (a) Fluorescence images of lysosomes, (b) nanodiamond and (c) merged image of nanodiamond internalization in macrophage. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

T cell-macrophage interaction in arginase-mediated resistance to herpes simplex virus.

Science.gov (United States)

Bonina, L; Nash, A A; Arena, A; Leung, K N; Wildy, P

1984-09-01

Peritoneal macrophages activated by-products derived from a herpes simplex virus-specific helper T cell clone were used to investigate intrinsic and extrinsic resistance mechanisms to herpes simplex virus type 1 infection in vitro. T cell-activated macrophages produced fewer infective centres, indicating enhanced intrinsic resistance, and markedly reduced the growth of virus in a permissive cell line. The reduction in virus growth correlated with the depletion of arginine in the support medium, presumably resulting from increased arginase production by activated macrophages. The significance of these findings for antiviral immunity in vivo is discussed.

Selective Inhibitors of Kv11.1 Regulate IL-6 Expression by Macrophages in Response to TLR/IL-1R Ligands

Directory of Open Access Journals (Sweden)

Cheryl Hunter

2010-01-01

Full Text Available The mechanism by which the platelet-endothelial cell adhesion molecule PECAM-1 regulates leukodiapedesis, vascular endothelial integrity, and proinflammatory cytokine expression in vivo is not known. We recently identified PECAM-1 as a negative regulator of Kv11.1, a specific voltage-gated potassium channel that functioned in human macrophages to reset a resting membrane potential following depolarization. We demonstrate here that dofetilide (DOF, a selective inhibitor of the Kv11.1 current, had a profound inhibitory effect on neutrophil recruitment in mice following TLR/IL-1R–elicited peritonitis or intrascrotal injection of IL-1β, but had no effect on responses seen with TNFα. Furthermore, inhibitors of Kv11.1 (DOF, E4031, and astemizole, but not Kv1.3 (margatoxin, suppressed the expression of IL-6 and MCP-1 cytokines by murine resident peritoneal macrophages, while again having no effect on TNFα. In contrast, IL-6 expression by peritoneal mesothelial cells was unaffected. Using murine P388 cells, which lack endogenous C/EBPβexpression and are unresponsive to LPS for the expression of both IL-6 and MCP-1, we observed that DOF inhibited LPS-induced expression of IL-6 mRNA following ectopic expression of wild-type C/EBPβ, but not a serine-64 point mutant. Finally, DOF inhibited the constitutive activation of cdk2 in murine peritoneal macrophages; cdk2 is known to phosphorylate C/EBPβ at serine-64. Taken together, our results implicate a potential role for Kv11.1 in regulating cdk2 and C/EBPβ activity, where robust transactivation of both IL-6 and MCP-1 transcription is known to be dependent on serine-64 of C/EBPβ. Our data might also explain the altered phenotypes displayed by PECAM-1 knockout mice in several disease models.

Exocytosis of macrophage lysosomes leads to digestion of apoptotic adipocytes and foam cell formation[S

Science.gov (United States)

Haka, Abigail S.; Barbosa-Lorenzi, Valéria C.; Lee, Hyuek Jong; Falcone, Domenick J.; Hudis, Clifford A.; Dannenberg, Andrew J.

2016-01-01

Many types of apoptotic cells are phagocytosed and digested by macrophages. Adipocytes can be hundreds of times larger than macrophages, so they are too large to be digested by conventional phagocytic processes. The nature of the interaction between macrophages and apoptotic adipocytes has not been studied in detail. We describe a cellular process, termed exophagy, that is important for macrophage clearance of dead adipocytes and adipose tissue homeostasis. Using mouse models of obesity, human tissue, and a cell culture model, we show that macrophages form hydrolytic extracellular compartments at points of contact with dead adipocytes using local actin polymerization. These compartments are acidic and contain lysosomal enzymes delivered by exocytosis. Uptake and complete degradation of adipocyte fragments, which are released by extracellular hydrolysis, leads to macrophage foam cell formation. Exophagy-mediated foam cell formation is a highly efficient means by which macrophages internalize large amounts of lipid, which may ultimately overwhelm the metabolic capacity of the macrophage. This process provides a mechanism for degradation of objects, such as dead adipocytes, that are too large to be phagocytosed by macrophages. PMID:27044658

Of macrophages and red blood cells; a complex love story

NARCIS (Netherlands)

de Back, Djuna Z.; Kostova, Elena B.; van Kraaij, Marian; van den Berg, Timo K.; van Bruggen, Robin

2014-01-01

Macrophages tightly control the production and clearance of red blood cells (RBC). During steady state hematopoiesis, approximately 10(10) RBC are produced per hour within erythroblastic islands in humans. In these erythroblastic islands, resident bone marrow macrophages provide erythroblasts with

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

Directory of Open Access Journals (Sweden)

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.

Dynamic activation of basilar membrane macrophages in response to chronic sensory cell degeneration in aging mouse cochleae.

Science.gov (United States)

Frye, Mitchell D; Yang, Weiping; Zhang, Celia; Xiong, Binbin; Hu, Bo Hua

2017-02-01

In the sensory epithelium, macrophages have been identified on the scala tympani side of the basilar membrane. These basilar membrane macrophages are the spatially closest immune cells to sensory cells and are able to directly respond to and influence sensory cell pathogenesis. While basilar membrane macrophages have been studied in acute cochlear stresses, their behavior in response to chronic sensory cell degeneration is largely unknown. Here we report a systematic observation of the variance in phenotypes, the changes in morphology and distribution of basilar membrane tissue macrophages in different age groups of C57BL/6J mice, a mouse model of age-related sensory cell degeneration. This study reveals that mature, fully differentiated tissue macrophages, not recently infiltrated monocytes, are the major macrophage population for immune responses to chronic sensory cell death. These macrophages display dynamic changes in their numbers and morphologies as age increases, and the changes are related to the phases of sensory cell degeneration. Notably, macrophage activation precedes sensory cell pathogenesis, and strong macrophage activity is maintained until sensory cell degradation is complete. Collectively, these findings suggest that mature tissue macrophages on the basilar membrane are a dynamic group of cells that are capable of vigorous adaptation to changes in the local sensory epithelium environment influenced by sensory cell status. Copyright © 2016 Elsevier B.V. All rights reserved.

Adrenomedullin Regulates IL-1β Gene Expression in F4/80+ Macrophages during Synovial Inflammation

Science.gov (United States)

Takano, Shotaro; Miyagi, Masayuki; Inoue, Gen; Aikawa, Jun; Iwabuchi, Kazuya; Takaso, Masashi

2017-01-01

Adrenomedullin (AM) plays an important role in the regulation of inflammatory processes; however, the role and expression of AM in synovial inflammation have not been determined. To investigate the expression and role of AM in inflamed synovial tissue (ST), the gene expression profiles of AM in the ST, including synovial macrophages and fibroblasts, of a murine patellar surgical dislocation model were characterized. In addition, the effects of interleukin- (IL-) 1β and AM in cultured synovial cells were also examined. CD11c+ macrophages were found to be elevated in ST of the surgically dislocated patella. Higher gene expression of CD11c, IL-1β, AM, receptor activity-modifying proteins 2 (RAMP2), and 3 (RAMP3) was also observed in ST obtained from the dislocated side. AM expression was also significantly increased in synovial fibroblasts and macrophages in response to IL-1β treatment. Synovial macrophages also highly expressed RAMP3 compared to fibroblasts and this expression was further stimulated by exogenously added IL-1β. Further, the treatment of the F4/80-positive cell fraction obtained from ST with AM inhibited IL-1β expression. Taken together, these findings demonstrated that AM was produced by synovial fibroblasts and macrophages in inflamed ST and that increased levels of AM may exert anti-inflammatory effects on synovial macrophages. PMID:28299347

Protective and recuperative effects of 3-bromopyruvate on immunological, hepatic and renal homeostasis in a murine host bearing ascitic lymphoma: Implication of niche dependent differential roles of macrophages.

Science.gov (United States)

Yadav, Saveg; Pandey, Shrish Kumar; Goel, Yugal; Kujur, Praveen Kumar; Maurya, Babu Nandan; Verma, Ashish; Kumar, Ajay; Singh, Rana Pratap; Singh, Sukh Mahendra

2018-03-01

3-bromopyruvate (3-BP) possesses promising antineoplastic potential, however, its effects on immunological homeostasis vis a vis hepatic and renal functions in a tumor bearing host remain unclear. Therefore, the effect of 3-BP administration to a murine host bearing a progressively growing tumor of thymoma origin, designated as Dalton's lymphoma (DL), on immunological, renal and hepatic homeostasis was investigated. Administration of 3-BP (4 mg/kg) to the tumor bearing host reversed tumor growth associated thymic atrophy and splenomegaly, accompanied by altered cell survival and repertoire of splenic, bone marrow and tumor associated macrophages (TAM). TAM displayed augmented phagocytic, tumoricidal activities and production of IL-1 and TNF-α. 3-BP-induced activation of TAM was of indirect nature, mediated by IFN-γ. Blood count of T lymphocytes (CD4 + & CD8 + ) and NK cells showed a rise in 3-BP administered tumor bearing mice. Moreover, 3-BP administration triggered modulation of immunomodulatory cytokines in serum along with refurbished hepatic and renal functions. The study indicates the role of altered cytokines balance, site specific differential macrophage functions and myelopoiesis in restoration of lymphoid organ homeostasis in 3-BP administered tumor bearing host. These observations will have long lasting impact in understanding of alternate mechanisms underlying the antitumor action of 3-BP accompanying appraisal of safety issues for optimizing its antineoplastic actions. Copyright © 2018 Elsevier Masson SAS. All rights reserved.

Tracking bacterial infection into macrophages by a novel red-emission pH sensor

OpenAIRE

Jin, Yuguang; Tian, Yanqing; Zhang, Weiwen; Jang, Sei-Hum; Jen, Alex K.-Y.; Meldrum, Deirdre R.

2010-01-01

The relationship between bacteria and host phagocytic cells is a key to the induction of immunity. To visualize and monitor bacterial infection, we developed a novel bacterial membrane permeable pH sensor for noninvasive monitoring of bacterial entry into murine macrophages. The pH sensor was constructed using 2-dicyanomethylene-3-cyano-4,5,5-trimethyl-2,5-dihydrofuran (TCF) as an electron-withdrawing group and aniline as an electron donating group. A piperazine moiety was u...

Response of Mammalian Macrophages to Challenge with the Chlorovirus Acanthocystis turfacea Chlorella Virus 1.

Science.gov (United States)

Petro, Thomas M; Agarkova, Irina V; Zhou, You; Yolken, Robert H; Van Etten, James L; Dunigan, David D

2015-12-01

It was recently reported that 44% of the oropharyngeal samples from the healthy humans in a study cohort had DNA sequences similar to that of the chlorovirus ATCV-1 (Acanthocystis turfacea chlorella virus 1, family Phycodnaviridae) and that these study subjects had decreases in visual processing and visual motor speed compared with individuals in whom no virus was detected. Moreover, mice inoculated orally with ATCV-1 developed immune responses to ATCV-1 proteins and had decreases in certain cognitive domains. Because heightened interleukin-6 (IL-6), nitric oxide (NO), and ERK mitogen-activated protein (MAP) kinase activation from macrophages are linked to cognitive impairments, we evaluated cellular responses and viral PFU counts in murine RAW264.7 cells and primary macrophages after exposure to ATCV-1 in vitro for up to 72 h after a virus challenge. Approximately 8% of the ATCV-1 inoculum was associated with macrophages after 1 h, and the percentage increased 2- to 3-fold over 72 h. Immunoblot assays with rabbit anti-ATCV-1 antibody detected a 55-kDa protein consistent with the viral capsid protein from 1 to 72 h and increasing de novo synthesis of a previously unidentified 17-kDa protein beginning at 24 h. Emergence of the 17-kDa protein did not occur and persistence of the 55-kDa protein declined over time when cells were exposed to heat-inactivated ATCV-1. Moreover, starting at 24 h, RAW264.7 cells exhibited cytopathic effects, annexin V staining, and cleaved caspase 3. Activation of ERK MAP kinases occurred in these cells by 30 min postchallenge, which preceded the expression of IL-6 and NO. Therefore, ATCV-1 persistence in and induction of inflammatory factors by these macrophages may contribute to declines in the cognitive abilities of mice and humans. Virus infections that persist in and stimulate inflammatory factors in macrophages contribute to pathologies in humans. A previous study showed that DNA sequences homologous to the chlorovirus ATCV-1 were

Characterization of the binding of radioiodinated hybrid recombinant IFN-alpha A/D to murine and human lymphoid cell lines

International Nuclear Information System (INIS)

Faltynek, C.R.; Princler, G.L.; Schwabe, M.; Shata, M.T.; Lewis, G.K.; Kamin-Lewis, R.M.

1990-01-01

The hybrid recombinant human interferon (IFN) rIFN-alpha A/D was radioiodinated. Specific binding of [125I]rIFN-alpha A/D was observed with both human and murine cell lines. The binding of [125I]rIFN-alpha A/D to human Daudi cells had similar characteristics to the previously described binding of [125I]rIFN-alpha A or -alpha 2. The following lines of evidence demonstrated that [125I]rIFN-alpha A/D bound with high affinity to the same receptor on murine cells as murine IFN-alpha and -beta: (i) the binding of [125I]rIFN-alpha A/D to murine LBRM cells was inhibited to a similar extent by natural murine IFN-alpha, natural murine IFN-beta, and rIFN-A/D; (ii) the Kd (approximately 2 X 10(-10) M) obtained from both competition experiments and saturation binding experiments with [125I]rIFN-alpha A/D was comparable to the previously reported Kd for the binding of natural murine IFN-alpha and -beta to other murine cell lines; (iii) the size of the cross-linked [125I]rIFN-alpha A/D receptor complex formed on murine LBRM cells was similar to the previously reported cross-linked complex formed after binding radioiodinated natural murine IFN-beta to other murine cell lines. Due to the current lack of readily available recombinant murine IFN-alpha or -beta for radiolabeling and the previously demonstrated biological activity of rIFN-alpha A/D on murine cells, [125I]rIFN-alpha A/D should prove to be a useful reagent for further studies of murine IFN receptors

microRNA-150 inhibits the formation of macrophage foam cells through targeting adiponectin receptor 2

Energy Technology Data Exchange (ETDEWEB)

Li, Jing [Department of Geratory, Linzi District People’s Hospital of Zibo City, Zibo, Shandong (China); Zhang, Suhua, E-mail: drsuhuangzhang@qq.com [Department of HealthCare, Qilu Hospital of Shandong University (Qingdao), Qingdao City, Qingdao (China)

2016-08-05

Transformation of macrophages into foam cells plays a critical role in the pathogenesis of atherosclerosis. The aim of this study was to determine the expression and biological roles of microRNA (miR)-150 in the formation of macrophage foam cells and to identify its functional target(s). Exposure to 50 μg/ml oxidized low-density lipoprotein (oxLDL) led to a significant upregulation of miR-150 in THP-1 macrophages. Overexpression of miR-150 inhibited oxLDL-induced lipid accumulation in THP-1 macrophages, while knockdown of miR-150 enhanced lipid accumulation. apoA-I- and HDL-mediated cholesterol efflux was increased by 66% and 43%, respectively, in miR-150-overexpressing macrophages relative to control cells. In contrast, downregulation of miR-150 significantly reduced cholesterol efflux from oxLDL-laden macrophages. Bioinformatic analysis and luciferase reporter assay revealed adiponectin receptor 2 (AdipoR2) as a direct target of miR-150. Small interfering RNA-mediated downregulation of AdipoR2 phenocopied the effects of miR-150 overexpression, reducing lipid accumulation and facilitating cholesterol efflux in oxLDL-treated THP-1 macrophages. Knockdown of AdipoR2 induced the expression of proliferator-activated receptor gamma (PPARγ), liver X receptor alpha (LXRα), ABCA1, and ABCG1. Moreover, pharmacological inhibition of PPARγ or LXRα impaired AdipoR2 silencing-induced upregulation of ABCA1 and ABCG1. Taken together, our results indicate that miR-150 can attenuate oxLDL-induced lipid accumulation in macrophages via promotion of cholesterol efflux. The suppressive effects of miR-150 on macrophage foam cell formation are mediated through targeting of AdipoR2. Delivery of miR-150 may represent a potential approach to prevent macrophage foam cell formation in atherosclerosis. -- Highlights: •miR-150 inhibits macrophage foam cell formation. •miR-150 accelerates cholesterol efflux from oxLDL-laden macrophages. •miR-150 suppresses macrophage foam cell

WNT7b mediates macrophage-induced programmed cell death in patterning of the vasculature

OpenAIRE

Lobov, Ivan B.; Rao, Sujata; Carroll, Thomas J.; Vallance, Jefferson E.; Ito, Masataka; Ondr, Jennifer K.; Kurup, Savita; Glass, Donald A.; Patel, Millan S.; Shu, Weiguo; Morrisey, Edward E.; McMahon, Andrew P.; Karsenty, Gerard; Lang, Richard A.

2005-01-01

Macrophages have a critical role in inflammatory and immune responses through their ability to recognize and engulf apoptotic cells1. Here we show that macrophages initiate a cell-death programme in target cells by activating the canonical WNT pathway. We show in mice that macrophage WNT7b is a short-range paracrine signal required for WNT-pathway responses and programmed cell death in the vascular endothelial cells of the temporary hyaloid vessels of the developing eye. These findings indica...

Macrophages inhibit human osteosarcoma cell growth after activation with the bacterial cell wall derivative liposomal muramyl tripeptide in combination with interferon-γ.

Science.gov (United States)

Pahl, Jens H W; Kwappenberg, Kitty M C; Varypataki, Eleni M; Santos, Susy J; Kuijjer, Marieke L; Mohamed, Susan; Wijnen, Juul T; van Tol, Maarten J D; Cleton-Jansen, Anne-Marie; Egeler, R Maarten; Jiskoot, Wim; Lankester, Arjan C; Schilham, Marco W

2014-03-10

In osteosarcoma, the presence of tumor-infiltrating macrophages positively correlates with patient survival in contrast to the negative effect of tumor-associated macrophages in patients with other tumors. Liposome-encapsulated muramyl tripeptide (L-MTP-PE) has been introduced in the treatment of osteosarcoma patients, which may enhance the potential anti-tumor activity of macrophages. Direct anti-tumor activity of human macrophages against human osteosarcoma cells has not been described so far. Hence, we assessed osteosarcoma cell growth after co-culture with human macrophages. Monocyte-derived M1-like and M2-like macrophages were polarized with LPS + IFN-γ, L-MTP-PE +/- IFN-γ or IL-10 and incubated with osteosarcoma cells. Two days later, viable tumor cell numbers were analyzed. Antibody-dependent effects were investigated using the therapeutic anti-EGFR antibody cetuximab. M1-like macrophages inhibited osteosarcoma cell growth when activated with LPS + IFN-γ. Likewise, stimulation of M1-like macrophages with liposomal muramyl tripeptide (L-MTP-PE) inhibited tumor growth, but only when combined with IFN-γ. Addition of the tumor-reactive anti-EGFR antibody cetuximab did not further improve the anti-tumor activity of activated M1-like macrophages. The inhibition was mediated by supernatants of activated M1-like macrophages, containing TNF-α and IL-1β. However, specific blockage of these cytokines, nitric oxide or reactive oxygen species did not inhibit the anti-tumor effect, suggesting the involvement of other soluble factors released upon macrophage activation. While LPS + IFN-γ-activated M2-like macrophages had low anti-tumor activity, IL-10-polarized M2-like macrophages were able to reduce osteosarcoma cell growth in the presence of the anti-EGFR cetuximab involving antibody-dependent tumor cell phagocytosis. This study demonstrates that human macrophages can be induced to exert direct anti-tumor activity against osteosarcoma cells. Our

Tumor associated macrophages protect colon cancer cells from TRAIL-induced apoptosis through IL-1beta-dependent stabilization of Snail in tumor cells.

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Pawan Kaler

2010-07-01

Full Text Available We recently reported that colon tumor cells stimulate macrophages to release IL-1beta, which in turn inactivates GSK3beta and enhances Wnt signaling in colon cancer cells, generating a self-amplifying loop that promotes the growth of tumor cells.Here we describe that macrophages protect HCT116 and Hke-3 colon cancer cells from TRAIL-induced apoptosis. Inactivation of IL-1beta by neutralizing IL-1beta antibody, or silencing of IL-1beta in macrophages inhibited their ability to counter TRAIL-induced apoptosis. Accordingly, IL-1beta was sufficient to inhibit TRAIL-induced apoptosis. TRAIL-induced collapse of the mitochondrial membrane potential (Delta psi and activation of caspases were prevented by macrophages or by recombinant IL-1beta. Pharmacological inhibition of IL-1beta release from macrophages by vitamin D(3, a potent chemopreventive agent for colorectal cancer, restored the ability of TRAIL to induce apoptosis of tumor cells cultured with macrophages. Macrophages and IL-1beta failed to inhibit TRAIL-induced apoptosis in HCT116 cells expressing dnIkappaB, dnAKT or dnTCF4, confirming that they oppose TRAIL-induced cell death through induction of Wnt signaling in tumor cells. We showed that macrophages and IL-1beta stabilized Snail in tumor cells in an NF-kappaB/Wnt dependent manner and that Snail deficient tumor cells were not protected from TRAIL-induced apoptosis by macrophages or by IL-1beta, demonstrating a crucial role of Snail in the resistance of tumor cells to TRAIL.We have identified a positive feedback loop between tumor cells and macrophages that propagates the growth and promotes the survival of colon cancer cells: tumor cells stimulate macrophages to secrete IL-1beta, which in turn, promotes Wnt signaling and stabilizes Snail in tumor cells, conferring resistance to TRAIL. Vitamin D(3 halts this amplifying loop by interfering with the release of IL-1beta from macrophages. Accordingly, vitamin D(3 sensitizes tumor cells to TRAIL

Ceramic modifications of porous titanium: effects on macrophage activation.

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Scislowska-Czarnecka, A; Menaszek, E; Szaraniec, B; Kolaczkowska, E

2012-12-01

Porous titanium is one of the most widely used implant materials because of its mechanical properties, however, it is also characterised by low bioactivity. To improve the above parameter we prepared three modifications of the porous (30 wt%) titanium (Ti) surface by covering it with bioactive hydroxyapatite (HA), bioglass (BG) and calcium silicate (CS). Subsequently we tested the impact of the modifications on macrophages directing the inflammatory response that might compromise the implant bioactivity. In the study we investigated the in vitro effects of the materials on murine cell line RAW 264.7 macrophage adherence, morphology and activation (production/release of metalloproteinase MMP-9 and pro- and anti-inflammatory cytokines). CS Ti decreased the macrophage adherence and up-regulated the release of several pro-inflammatory mediators, including TNF-α, IL-6, IL-12. Also HA Ti reduced the cell adherence but other parameters were generally not increased, except of TNF-α. In contrast, BG Ti improved macrophage adherence and either decreased production of multiple mediators (MMP-9, TNF-α, IFN-γ, MCP-1) or did not change it in comparison to the porous titanium. We can conclude that analyzing the effects on the inflammatory response initiated by macrophages in vitro, calcium silicate did not improve the biological properties of the porous titanium. The improved bioactivity of titanium was, however, achieved by the application of the hydroxyapatite and bioglass layers. The present in vitro results suggest that these materials, HA Ti and especially BG Ti, may be suitable for in vivo application and thus justify their further investigation. Copyright © 2012 Elsevier Ltd. All rights reserved.

Pure Δ9-tetrahydrocannabivarin and a Cannabis sativa extract with high content in Δ9-tetrahydrocannabivarin inhibit nitrite production in murine peritoneal macrophages.

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Romano, Barbara; Pagano, Ester; Orlando, Pierangelo; Capasso, Raffaele; Cascio, Maria Grazia; Pertwee, Roger; Marzo, Vincenzo Di; Izzo, Angelo A; Borrelli, Francesca

2016-11-01

Historical and scientific evidence suggests that Cannabis use has immunomodulatory and anti-inflammatory effects. We have here investigated the effect of the non-psychotropic phytocannabinoid Δ 9 -tetrahydrocannabivarin (THCV) and of a Cannabis sativa extract with high (64.8%) content in THCV (THCV-BDS) on nitric oxide (NO) production, and on cannabinoid and transient receptor potential (TRP) channel expression in lipopolysaccharide (LPS)-stimulated murine peritoneal macrophages. THCV-BDS and THCV exhibited similar affinity in radioligand binding assays for CB 1 and CB 2 receptors, and inhibited, via CB 2 but not CB 1 cannabinoid receptors, nitrite production evoked by LPS in peritoneal macrophages. THCV down-regulated the over-expression of inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2) and interleukin 1β (IL-1β) proteins induced by LPS. Furthermore, THCV counteracted LPS-induced up-regulation of CB 1 receptors, without affecting the changes in CB 2 , TRPV2 or TRPV4 mRNA expression caused by LPS. Other TRP channels, namely, TRPA1, TRPV1, TRPV3 and TRPM8 were poorly expressed or undetectable in both unstimulated and LPS-challenged macrophages. It is concluded that THCV - via CB 2 receptor activation - inhibits nitrite production in macrophages. The effect of this phytocannabinoid was associated with a down-regulation of CB 1 , but not CB 2 or TRP channel mRNA expression. Copyright © 2016 Elsevier Ltd. All rights reserved.

Human glioblastoma-associated microglia/monocytes express a distinct RNA profile compared to human control and murine samples.

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Szulzewsky, Frank; Arora, Sonali; de Witte, Lot; Ulas, Thomas; Markovic, Darko; Schultze, Joachim L; Holland, Eric C; Synowitz, Michael; Wolf, Susanne A; Kettenmann, Helmut

2016-08-01

Glioblastoma (GBM) is the most aggressive brain tumor in adults. It is strongly infiltrated by microglia and peripheral monocytes that support tumor growth. In the present study we used RNA sequencing to compare the expression profile of CD11b(+) human glioblastoma-associated microglia/monocytes (hGAMs) to CD11b(+) microglia isolated from non-tumor samples. Hierarchical clustering and principal component analysis showed a clear separation of the two sample groups and we identified 334 significantly regulated genes in hGAMs. In comparison to human control microglia hGAMs upregulated genes associated with mitotic cell cycle, cell migration, cell adhesion, and extracellular matrix organization. We validated the expression of several genes associated with extracellular matrix organization in samples of human control microglia, hGAMs, and the hGAMs-depleted fraction via qPCR. The comparison to murine GAMs (mGAMs) showed that both cell populations share a significant fraction of upregulated transcripts compared with their respective controls. These genes were mostly related to mitotic cell cycle. However, in contrast to murine cells, human GAMs did not upregulate genes associated to immune activation. Comparison of human and murine GAMs expression data to several data sets of in vitro-activated human macrophages and murine microglia showed that, in contrast to mGAMs, hGAMs share a smaller overlap to these data sets in general and in particular to cells activated by proinflammatory stimulation with LPS + INFγ or TNFα. Our findings provide new insights into the biology of human glioblastoma-associated microglia/monocytes and give detailed information about the validity of murine experimental models. GLIA 2016 GLIA 2016;64:1416-1436. © 2016 Wiley Periodicals, Inc.

Mitochondrial function is involved in regulation of cholesterol efflux to apolipoprotein (apoA-I from murine RAW 264.7 macrophages

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Allen Anne Marie

2012-12-01

Full Text Available Abstract Background Mitochondrial DNA damage, increased production of reactive oxygen species and progressive respiratory chain dysfunction, together with increased deposition of cholesterol and cholesteryl esters, are hallmarks of atherosclerosis. This study investigated the role of mitochondrial function in regulation of macrophage cholesterol efflux to apolipoprotein A-I, by the addition of established pharmacological modulators of mitochondrial function. Methods Murine RAW 264.7 macrophages were treated with a range of concentrations of resveratrol, antimycin, dinitrophenol, nigericin and oligomycin, and changes in viability, cytotoxicity, membrane potential and ATP, compared with efflux of [3H]cholesterol to apolipoprotein (apo A-I. The effect of oligomycin treatment on expression of genes implicated in macrophage cholesterol homeostasis were determined by quantitative polymerase chain reaction, and immunoblotting, relative to the housekeeping enzyme, Gapdh, and combined with studies of this molecule on cholesterol esterification, de novo lipid biosynthesis, and induction of apoptosis. Significant differences were determined using analysis of variance, and Dunnett’s or Bonferroni post t-tests, as appropriate. Results The positive control, resveratrol (24 h, significantly enhanced cholesterol efflux to apoA-I at concentrations ≥30 μM. By contrast, cholesterol efflux to apoA-I was significantly inhibited by nigericin (45%; ppAbca1 mRNA. Oligomycin treatment did not affect cholesterol biosynthesis, but significantly inhibited cholesterol esterification following exposure to acetylated LDL, and induced apoptosis at ≥30 μM. Finally, oligomycin induced the expression of genes implicated in both cholesterol efflux (Abca1, Abcg4, Stard1 and cholesterol biosynthesis (Hmgr, Mvk, Scap, Srebf2, indicating profound dysregulation of cholesterol homeostasis. Conclusions Acute loss of mitochondrial function, and in particular Δψm, reduces

Streptococcus gordonii induces nitric oxide production through its lipoproteins stimulating Toll-like receptor 2 in murine macrophages.

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Kim, Hyun Young; Baik, Jung Eun; Ahn, Ki Bum; Seo, Ho Seong; Yun, Cheol-Heui; Han, Seung Hyun

2017-02-01

Streptococcus gordonii, a Gram-positive commensal in the oral cavity, is an opportunistic pathogen that can cause endodontic and systemic infections resulting in infective endocarditis. Lipoteichoic acid (LTA) and lipoprotein are major virulence factors of Gram-positive bacteria that are preferentially recognized by Toll-like receptor 2 (TLR2) on immune cells. In the present study, we investigated the effect of S. gordonii LTA and lipoprotein on the production of the representative inflammatory mediator nitric oxide (NO) by the mouse macrophages. Heat-killed S. gordonii wild-type and an LTA-deficient mutant (ΔltaS) but not a lipoprotein-deficient mutant (Δlgt) induced NO production in mouse primary macrophages and the cell line, RAW 264.7. S. gordonii wild-type and ΔltaS also induced the expression of inducible NO synthase (iNOS) at the mRNA and protein levels. In contrast, the Δlgt mutant showed little effect under the same condition. Furthermore, S. gordonii wild-type and ΔltaS induced NF-κB activation, STAT1 phosphorylation, and IFN-β expression, which are important for the induction of iNOS gene expression, with little activation by Δlgt. S. gordonii wild-type and ΔltaS showed an increased adherence and internalization to RAW 264.7 cells compared to Δlgt. In addition, S. gordonii wild-type and ΔltaS, but not Δlgt, substantially increased TLR2 activation while none of these induced NO production in TLR2-deficient macrophages. Triton X-114-extracted lipoproteins from S. gordonii were sufficient to induce NO production. Collectively, we suggest that lipoprotein is an essential cell wall component of S. gordonii to induce NO production in macrophages through TLR2 triggering NF-κB and STAT1 activation. Copyright © 2016 Elsevier Ltd. All rights reserved.

Splenic red pulp macrophages are intrinsically superparamagnetic and contaminate magnetic cell isolates.

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Franken, Lars; Klein, Marika; Spasova, Marina; Elsukova, Anna; Wiedwald, Ulf; Welz, Meike; Knolle, Percy; Farle, Michael; Limmer, Andreas; Kurts, Christian

2015-08-11

A main function of splenic red pulp macrophages is the degradation of damaged or aged erythrocytes. Here we show that these macrophages accumulate ferrimagnetic iron oxides that render them intrinsically superparamagnetic. Consequently, these cells routinely contaminate splenic cell isolates obtained with the use of MCS, a technique that has been widely used in immunological research for decades. These contaminations can profoundly alter experimental results. In mice deficient for the transcription factor SpiC, which lack red pulp macrophages, liver Kupffer cells take over the task of erythrocyte degradation and become superparamagnetic. We describe a simple additional magnetic separation step that avoids this problem and substantially improves purity of magnetic cell isolates from the spleen.

Macrophages, Foreign Body Giant Cells and Their Response to Implantable Biomaterials

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Zeeshan Sheikh

2015-08-01

Full Text Available All biomaterials, when implanted in vivo, elicit cellular and tissue responses. These responses include the inflammatory and wound healing responses, foreign body reactions, and fibrous encapsulation of the implanted materials. Macrophages are myeloid immune cells that are tactically situated throughout the tissues, where they ingest and degrade dead cells and foreign materials in addition to orchestrating inflammatory processes. Macrophages and their fused morphologic variants, the multinucleated giant cells, which include the foreign body giant cells (FBGCs are the dominant early responders to biomaterial implantation and remain at biomaterial-tissue interfaces for the lifetime of the device. An essential aspect of macrophage function in the body is to mediate degradation of bio-resorbable materials including bone through extracellular degradation and phagocytosis. Biomaterial surface properties play a crucial role in modulating the foreign body reaction in the first couple of weeks following implantation. The foreign body reaction may impact biocompatibility of implantation devices and may considerably impact short- and long-term success in tissue engineering and regenerative medicine, necessitating a clear understanding of the foreign body reaction to different implantation materials. The focus of this review article is on the interactions of macrophages and foreign body giant cells with biomaterial surfaces, and the physical, chemical and morphological characteristics of biomaterial surfaces that play a role in regulating the foreign body response. Events in the foreign body response include protein adsorption, adhesion of monocytes/macrophages, fusion to form FBGCs, and the consequent modification of the biomaterial surface. The effect of physico-chemical cues on macrophages is not well known and there is a complex interplay between biomaterial properties and those that result from interactions with the local environment. By having a

Sperm-macrophage interaction in the mouse: a quantitative assay in vitro using 111indium oxine-labeled sperm

International Nuclear Information System (INIS)

Olive, D.L.; Weinberg, J.B.; Haney, A.F.

1987-01-01

The role of reproductive tract macrophages in contraception and reproductive failure has become widely recognized. However, in vitro analysis of sperm phagocytosis by macrophages has relied upon a semi-quantitative method of sperm counting that is of limited accuracy and reproducibility. We have developed an assay using murine sperm labeled with 111 indium oxine, and results indicate the labeling to be rapid and efficient. Incorporation of 111 indium into sperm increased the dose and sperm concentration and reached 90% maximal uptake after 15 min incubation, with maximal uptake occurring at 30 min. No decrease in sperm motility was noted with levels of oxine in excess of those required for significant labeling. Maximal labeling efficiency occurred in phosphate-buffered saline (PBS), with Dulbecco's modified Eagle's medium (DMEM) + 10% adult bovine serum (ABS) producing significantly less uptake. Label dissociation was detectable in PBS at room temperature, but at 37 degrees C in DMEM + 10% ABS, loss of label occurred at a rate of 23.5%/h. Addition of labeled sperm to murine macrophage monolayers under optimal conditions resulted in uptake of 111 indium by macrophages, while free label was unincorporated. Results indicated assay specificity for macrophage-limited uptake, with insignificant label uptake by nonphagocytic murine fibroblasts and better sensitivity than sperm counting. Macrophages from Bacillus Calmette-Guerin (BCG)-infected mice resulted in a decrease in sperm uptake. Female macrophages showed greater capacity for sperm uptake than those of the male mouse. These initial studies demonstrated the utility of this model system in enhancing the understanding of sperm-macrophage interaction in the female reproductive tract

stg fimbrial operon from S. Typhi STH2370 contributes to association and cell disruption of epithelial and macrophage-like cells.

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Berrocal, Liliana; Fuentes, Juan A; Trombert, A Nicole; Jofré, Matías R; Villagra, Nicolás A; Valenzuela, Luis M; Mora, Guido C

2015-07-07

Salmonella enterica serovar Typhi (S. Typhi) stg operon, encoding a chaperone/usher fimbria (CU), contributes to an increased adherence to human epithelial cells. However, one report suggests that the presence of the Stg fimbria impairs the monocyte--bacteria association, as deduced by the lower level of invasion to macrophage-like cells observed when the stg fimbrial cluster was overexpressed. Nevertheless, since other CU fimbrial structures increase the entry of S. Typhi into macrophages, and considering that transcriptomic analyses revealed that stg operon is indeed expressed in macrophages, we reassessed the role of the stg operon in the interaction between S. Typhi strain STH2370 and human cells, including macrophage-like cells and mononuclear cells directly taken from human peripheral blood. We compared S. Typhi STH2370 WT, a Chilean clinical strain, and the S. Typhi STH2370 Δstg mutant with respect to association and invasion using epithelial and macrophage-like cells. We observed that deletion of stg operon reduced the association and invasion of S. Typhi, in both cellular types. The presence of the cloned stg operon restored the WT phenotype in all the cases. Moreover, we compared Salmonella enterica sv. Typhimurium 14028s (S. Typhimurium, a serovar lacking stg operon) and S. Typhimurium heterologously expressing S. Typhi stg. We found that the latter presents an increased cell disruption of polarized epithelial cells and an increased association in both epithelial and macrophage-like cells. S. Typhi stg operon encodes a functional adhesin that participates in the interaction bacteria-eukaryotic cells, including epithelial cells and macrophages-like cells. The phenotypes associated to stg operon include increased association and consequent invasion in bacteria-eukaryotic cells, and cell disruption.

Apoptosis induction and attenuation of inflammatory gene expression in murine macrophages via multitherapeutic nanomembranes

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Pierstorff, Erik; Krucoff, Max; Ho, Dean

2008-01-01

The realization of optimized therapeutic delivery is impaired by the challenge of localized drug activity and by the dangers of systemic cytotoxicity which often contribute to patient treatment complications. Here we demonstrate the block copolymer-mediated deposition and release of multiple therapeutics which include an LXRα/β agonist 3-((4-methoxyphenyl)amino)-4-phenyl-1-(phenylmethyl)-1H-pyrrole-2,5-dione (LXRa) and doxorubicin hydrochloride (Dox) at the air-water interface via Langmuir-Blodgett deposition, as well as copolymer-mediated potent drug elution toward the Raw 264.7 murine macrophage cell line. The resultant copolymer-therapeutic hybrid serves as a localized platform that can be functionalized with virtually any drug due to the integrated hydrophilic and hydrophobic components of the polymer structure. In addition, the sequestering function of the copolymer to anchor the drugs to implant surfaces can enhance delivery specificity when compared to systemic drug administration. Confirmation of drug functionality was confirmed via suppression of the interleukin 6 (Il-6) and tumor necrosis factor alpha (TNFα) inflammatory cytokines (LXRa), as well as DNA fragmentation analysis (Dox). Furthermore, the fragmentation assays and gene expression analysis demonstrated the innate biocompatibility of the copolymeric material at the gene expression level via the confirmed absence of material-induced apoptosis and a lack of inflammatory gene expression. This modality enables layer-by-layer control of agonist and chemotherapeutic functionalization at the nanoscale for the localization of drug dosage, while simultaneously utilizing the copolymer platform as an anchoring mechanism for drug sequestering, all with an innate material thickness of 4 nm per layer, which is orders of magnitude thinner than existing commercial technologies. Furthermore, these studies comprehensively confirmed the potential translational applicability of copolymeric nanomaterials as

Clearance and binding of radiolabeled glycoproteins by cells of the murine mononuclear phagocyte system

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Imber, M.J.

1982-01-01

The clearance and binding of radiolabeled lactoferrin and fast α 2 -macroglobulin were studied. Both glycoproteins cleared rapidly following intravenous injection in mice, and both bound specifically to discrete receptors on murine peritoneal macrophages. The simultaneous presence of excess, unlabeled ligands specific for receptors recognizing terminal fucose, mannose, N-acetylglucosamine or galactose residues did not inhibit the clearance or binding of either lactoferrin or fast-α 2 M. The clearance and binding of enzymatically defucosylated lactoferrin was indistinguishable from native lactoferrin, indicating that terminal α(1-3)-linked fucose on lactoferrin is not necessary for receptor recognition. The clearance and binding of two fast -α 2 M forms, α 2 M-trypsin and α 2 M-MeNH 2 cross compete with each other. Saturation binding studies indicated that the total binding of mannosyl -BSA, fusocyl-BSA, and N-acetylglucosaminyl-BSA to macrophages activated by BCG was approximately 15% of the levels observed with inflammatory macrophages elicited by thioglycollate broth. Cross-competition binding studies demonstrated a common surface receptor mediated binding of all three neoglycoprotein ligands and was identical to the receptor on mononuclear phagocytes that binds mannosyl- and N-acetylglucosaminyl-terminated glycoproteins. These results suggest that difference between discrete states of macrophage function may be correlated with selective changes in levels of the surface receptor for mannose-containing glycoproteins

Inflammation induced mTORC2-Akt-mTORC1 signaling promotes macrophage foam cell formation.

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Banerjee, Dipanjan; Sinha, Archana; Saikia, Sudeshna; Gogoi, Bhaskarjyoti; Rathore, Arvind K; Das, Anindhya Sundar; Pal, Durba; Buragohain, Alak K; Dasgupta, Suman

2018-06-05

The transformation of macrophages into lipid loaded foam cells is a critical and early event in the pathogenesis of atherosclerosis. Several recent reports highlighted that induction of TLR4 signaling promotes macrophage foam cell formation; however, the underlying molecular mechanisms have not been clearly elucidated. Here, we found that the TLR4 mediated inflammatory signaling communicated with mTORC2-Akt-mTORC1 metabolic cascade in macrophage and thereby promoting lipid uptake and foam cell formation. Mechanistically, LPS treatment markedly upregulates TLR4 mediated inflammatory pathway which by activating mTORC2 induces Akt phosphorylation at serine 473 and that aggravate mTORC1 dependent scavenger receptors expression and consequent lipid accumulation in THP-1 macrophages. Inhibition of mTORC2 either by silencing Rictor expression or inhibiting its association with mTOR notably prevents LPS induced Akt activation, scavenger receptors expression and macrophage lipid accumulation. Although suppression of mTORC1 expression by genetic knockdown of Raptor did not produce any significant change in Akt S473 phosphorylation, however, incubation with Akt activator in Rictor silenced cells failed to promote scavenger receptors expression and macrophage foam cell formation. Thus, present research explored the signaling pathway involved in inflammation induced macrophage foam cells formation and therefore, targeting this pathway might be useful for preventing macrophage foam cell formation. Copyright © 2018 Elsevier B.V. and Société Française de Biochimie et Biologie Moléculaire (SFBBM). All rights reserved.

Enhanced detection and study of murine norovirus-1 using a more efficient microglial cell line

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Lu Yuanan

2009-11-01

Full Text Available Abstract Background Human Noroviruses are the predominant cause of non-bacterial gastroenteritis worldwide. To facilitate prevention and control, a norovirus isolated from mice can provide a model to understand human noroviruses. To establish optimal viral infectivity conditions for murine noroviruses, several cell lines of hematopoietic lineage, including murine BV-2, RAW 264.7, and TIB, as well as human CHME-5, were tested comparatively for their sensitivity to murine norovirus-1. Results Except for CHME-5, all three murine-derived cell lines were susceptible to MNV infection. Viral infection of these cells was confirmed by RT-PCR. Using both viral plaque and replication assays, BV-2 and RAW 264.7 cells were determined to have comparable sensitivities to MNV-1 infection. Comparisons of cell growth characteristics, general laboratory handling and potential in-field applications suggest the use of BV-2 to be more advantageous. Conclusion Results obtained from these studies demonstrate that an immortalized microglial cell line can support MNV-1 replication and provides a more efficient method to detect and study murine noroviruses, facilitating future investigations using MNV-1 as a model to study, detect, and control Human Norovirus.

BIGH3 protein and macrophages in retinal endothelial cell apoptosis.

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Mondragon, Albert A; Betts-Obregon, Brandi S; Moritz, Robert J; Parvathaneni, Kalpana; Navarro, Mary M; Kim, Hong Seok; Lee, Chi Fung; LeBaron, Richard G; Asmis, Reto; Tsin, Andrew T

2015-01-01

Diabetes is a pandemic disease with a higher occurrence in minority populations. The molecular mechanism to initiate diabetes-associated retinal angiogenesis remains largely unknown. We propose an inflammatory pathway of diabetic retinopathy in which macrophages in the diabetic eye provide TGFβ to retinal endothelial cells (REC) in the retinal microvasculature. In response to TGFβ, REC synthesize and secrete a pro-apoptotic BIGH3 (TGFβ-Induced Gene Human Clone 3) protein, which acts in an autocrine loop to induce REC apoptosis. Rhesus monkey retinal endothelial cells (RhREC) were treated with dMCM (cell media of macrophages treated with high glucose and LDL) and assayed for apoptosis (TUNEL), BIGH3 mRNA (qPCR), and protein (Western blots) expressions. Cells were also treated with ΤGFβ1 and 2 for BIGH3 mRNA and protein expression. Inhibition assays were carried out using antibodies for TGFβ1 and for BIGH3 to block apoptosis and mRNA expression. BIGH3 in cultured RhREC cells were identified by immunohistochemistry (IHC). Distribution of BIGH3 and macrophages in the diabetic mouse retina was examined with IHC. RhRECs treated with dMCM or TGFβ showed a significant increase in apoptosis and BIGH3 protein expression. Recombinant BIGH3 added to RhREC culture medium led to a dose-dependent increase in apoptosis. Antibodies (Ab) directed against BIGH3 and TGFβ, as well as TGFβ receptor blocker resulted in a significant reduction in apoptosis induced by either dMCM, TGFβ or BIGH3. IHC showed that cultured RhREC constitutively expressed BIGH3. Macrophage and BIGH3 protein were co-localized to the inner retina of the diabetic mouse eye. Our results support a novel inflammatory pathway for diabetic retinopathy. This pathway is initiated by TGFβ released from macrophages, which promotes synthesis and release of BIGH3 protein by REC and REC apoptosis.

Novel keto-phospholipids are generated by monocytes and macrophages, detected in cystic fibrosis, and activate peroxisome proliferator-activated receptor-γ.

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Hammond, Victoria J; Morgan, Alwena H; Lauder, Sarah; Thomas, Christopher P; Brown, Sarah; Freeman, Bruce A; Lloyd, Clare M; Davies, Jane; Bush, Andrew; Levonen, Anna-Liisa; Kansanen, Emilia; Villacorta, Luis; Chen, Y Eugene; Porter, Ned; Garcia-Diaz, Yoel M; Schopfer, Francisco J; O'Donnell, Valerie B

2012-12-07

12/15-Lipoxygenases (LOXs) in monocytes and macrophages generate novel phospholipid-esterified eicosanoids. Here, we report the generation of two additional families of related lipids comprising 15-ketoeicosatetraenoic acid (KETE) attached to four phosphatidylethanolamines (PEs). The lipids are generated basally by 15-LOX in IL-4-stimulated monocytes, are elevated on calcium mobilization, and are detected at increased levels in bronchoalveolar lavage fluid from cystic fibrosis patients (3.6 ng/ml of lavage). Murine peritoneal macrophages generate 12-KETE-PEs, which are absent in 12/15-LOX-deficient mice. Inhibition of 15-prostaglandin dehydrogenase prevents their formation from exogenous 15-hydroxyeicosatetraenoic acid-PE in human monocytes. Both human and murine cells also generated analogous hydroperoxyeicosatetraenoic acid-PEs. The electrophilic reactivity of KETE-PEs is shown by their Michael addition to glutathione and cysteine. Lastly, both 15-hydroxyeicosatetraenoic acid-PE and 15-KETE-PE activated peroxisome proliferator-activated receptor-γ reporter activity in macrophages in a dose-dependent manner. In summary, we demonstrate novel peroxisome proliferator-activated receptor-γ-activating oxidized phospholipids generated enzymatically by LOX and 15-prostaglandin dehydrogenase in primary monocytic cells and in a human Th2-related lung disease. The lipids are a new family of bioactive mediators from the 12/15-LOX pathway that may contribute to its known anti-inflammatory actions in vivo.

Osteoclasts Are Required for Hematopoietic Stem and Progenitor Cell Mobilization but Not for Stress Erythropoiesis in Plasmodium chabaudi adami Murine Malaria

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Hugo Roméro

2016-01-01

Full Text Available The anemia and inflammation concurrent with blood stage malaria trigger stress haematopoiesis and erythropoiesis. The activity of osteoclasts seems required for the mobilization of hematopoietic stem and progenitor cells (HSPC from the bone marrow to the periphery. Knowing that BALB/c mice with acute Plasmodium chabaudi adami malaria have profound alterations in bone remodelling cells, we evaluated the extent to which osteoclasts influence their hematopoietic response to infection. For this, mice were treated with osteoclast inhibiting hormone calcitonin prior to parasite inoculation, and infection as well as hematological parameters was studied. In agreement with osteoclast-dependent HSPC mobilization, administration of calcitonin led to milder splenomegaly, reduced numbers of HSPC in the spleen, and their retention in the bone marrow. Although C-terminal telopeptide (CTX levels, indicative of bone resorption, were lower in calcitonin-treated infected mice, they remained comparable in naive and control infected mice. Calcitonin-treated infected mice conveniently responded to anemia but generated less numbers of splenic macrophages and suffered from exacerbated infection; interestingly, calcitonin also decreased the number of macrophages generated in vitro. Globally, our results indicate that although osteoclast-dependent HSC mobilization from bone marrow to spleen is triggered in murine blood stage malaria, this activity is not essential for stress erythropoiesis.

Activation of murine macrophages by lipoprotein and lipooligosaccharide of Treponema denticola.

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Rosen, G; Sela, M N; Naor, R; Halabi, A; Barak, V; Shapira, L

1999-03-01

We have recently demonstrated that the periodontopathogenic oral spirochete Treponema denticola possesses membrane-associated lipoproteins in addition to lipooligosaccharide (LOS). The aim of the present study was to test the potential of these oral spirochetal components to induce the production of inflammatory mediators by human macrophages, which in turn may stimulate tissue breakdown as observed in periodontal diseases. An enriched lipoprotein fraction (dLPP) from T. denticola ATCC 35404 obtained upon extraction of the treponemes with Triton X-114 was found to stimulate the production of nitric oxide (NO), tumor necrosis factor alpha (TNF-alpha), and interleukin-1 (IL-1) by mouse macrophages in a dose-dependent manner. Induction of NO by dLPP was at 25% of the levels obtained by Salmonella typhosa lipopolysaccharide (LPS) at similar concentrations, while IL-1 was produced at similar levels by both inducers. dLPP-mediated macrophage activation was unaffected by amounts of polymyxin B that neutralized the induction produced by S. typhosa LPS. dLPP also induced NO and TNF-alpha secretion from macrophages isolated from endotoxin-unresponsive C3H/HeJ mice to an extent similar to the stimulation produced in endotoxin-responsive mice. Purified T. denticola LOS also produced a concentration-dependent activation of NO and TNF-alpha in LPS-responsive and -nonresponsive mouse macrophages. However, macrophage activation by LOS was inhibited by polymyxin B. These results suggest that T. denticola lipoproteins and LOS may play a role in the inflammatory processes that characterize periodontal diseases.

Strain specific transcriptional response in Mycobacterium tuberculosis infected macrophages

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Koo Mi-Sun

2012-01-01

Full Text Available Abstract Background Tuberculosis (TB, a bacterial infection caused by Mycobacterium tuberculosis (Mtb remains a significant health problem worldwide with a third of the world population infected and nearly nine million new cases claiming 1.1 million deaths every year. The outcome following infection by Mtb is determined by a complex and dynamic host-pathogen interaction in which the phenotype of the pathogen and the immune status of the host play a role. However, the molecular mechanism by which Mtb strains induce different responses during intracellular infection of the host macrophage is not fully understood. To explore the early molecular events triggered upon Mtb infection of macrophages, we studied the transcriptional responses of murine bone marrow-derived macrophages (BMM to infection with two clinical Mtb strains, CDC1551 and HN878. These strains have previously been shown to differ in their virulence/immunogenicity in the mouse and rabbit models of pulmonary TB. Results In spite of similar intracellular growth rates, we observed that compared to HN878, infection by CDC1551 of BMM was associated with an increased global transcriptome, up-regulation of a specific early (6 hours immune response network and significantly elevated nitric oxide production. In contrast, at 24 hours post-infection of BMM by HN878, more host genes involved in lipid metabolism, including cholesterol metabolism and prostaglandin synthesis were up-regulated, compared to infection with CDC1551. In association with the differences in the macrophage responses to infection with the 2 Mtb strains, intracellular CDC1551 expressed higher levels of stress response genes than did HN878. Conclusions In association with the early and more robust macrophage activation, intracellular CDC1551 cells were exposed to a higher level of stress leading to increased up-regulation of the bacterial stress response genes. In contrast, sub-optimal activation of macrophages and induction of

Exosomes derived from gastric cancer cells activate NF-κB pathway in macrophages to promote cancer progression.

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Wu, Lijun; Zhang, Xu; Zhang, Bin; Shi, Hui; Yuan, Xiao; Sun, Yaoxiang; Pan, Zhaoji; Qian, Hui; Xu, Wenrong

2016-09-01

Exosomes are nano-sized membrane vesicles secreted by both normal and cancer cells. Emerging evidence indicates that cancer cells derived exosomes contribute to cancer progression through the modulation of tumor microenvironment. However, the effects of exosomes derived from gastric cancer cells on macrophages are not well understood. In this study, we investigated the biological role of gastric cancer cells derived exosomes in the activation of macrophages. We demonstrated that gastric cancer cells derived exosomes activated macrophages to express increased levels of proinflammatory factors, which in turn promoted tumor cell proliferation and migration. In addition, gastric cancer cells derived exosomes remarkably upregulated the phosphorylation of NF-κB in macrophages. Inhibiting the activation of NF-κB reversed the upregulation of proinflammatory factors in macrophages and blocked their promoting effects on gastric cancer cells. Moreover, we found that gastric cancer cells derived exosomes could also activate macrophages from human peripheral blood monocytes through the activation of NF-κB. In conclusion, our results suggest that gastric cancer cells derived exosomes stimulate the activation of NF-κB pathway in macrophages to promote cancer progression, which provides a potential therapeutic approach for gastric cancer by interfering with the interaction between exosomes and macrophages in tumor microenvironment.

Macrophage Liver Kinase B1 Inhibits Foam Cell Formation and Atherosclerosis.

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Liu, Zhaoyu; Zhu, Huaiping; Dai, Xiaoyan; Wang, Cheng; Ding, Ye; Song, Ping; Zou, Ming-Hui

2017-10-13

LKB1 (liver kinase B1) is a serine/threonine kinase and tumor suppressor, which regulates the homeostasis of hematopoietic cells and immune responses. Macrophages transform into foam cells upon taking-in lipids. No role for LKB1 in foam cell formation has previously been reported. We sought to establish the role of LKB1 in atherosclerotic foam cell formation. LKB1 expression was examined in human carotid atherosclerotic plaques and in western diet-fed atherosclerosis-prone Ldlr -/- and ApoE -/- mice. LKB1 expression was markedly reduced in human plaques when compared with nonatherosclerotic vessels. Consistently, time-dependent reduction of LKB1 levels occurred in atherosclerotic lesions in western diet-fed Ldlr -/- and ApoE -/- mice. Exposure of macrophages to oxidized low-density lipoprotein downregulated LKB1 in vitro. Furthermore, LKB1 deficiency in macrophages significantly increased the expression of SRA (scavenger receptor A), modified low-density lipoprotein uptake and foam cell formation, all of which were abolished by blocking SRA. Further, we found LKB1 phosphorylates SRA resulting in its lysosome degradation. To further investigate the role of macrophage LKB1 in vivo, ApoE -/- LKB1 fl/fl LysM cre and ApoE -/- LKB1 fl/fl mice were fed with western diet for 16 weeks. Compared with ApoE -/- LKB1 fl/fl wild-type control, ApoE -/- LKB1 fl/fl LysM cre mice developed more atherosclerotic lesions in whole aorta and aortic root area, with markedly increased SRA expression in aortic root lesions. We conclude that macrophage LKB1 reduction caused by oxidized low-density lipoprotein promotes foam cell formation and the progression of atherosclerosis. © 2017 American Heart Association, Inc.

Extracellular Purine Metabolism Is the Switchboard of Immunosuppressive Macrophages and a Novel Target to Treat Diseases With Macrophage Imbalances

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Anna Ohradanova-Repic

2018-04-01

Full Text Available If misregulated, macrophage (Mϕ–T cell interactions can drive chronic inflammation thereby causing diseases, such as rheumatoid arthritis (RA. We report that in a proinflammatory environment, granulocyte-Mϕ (GM-CSF- and Mϕ colony-stimulating factor (M-CSF-dependent Mϕs have dichotomous effects on T cell activity. While GM-CSF-dependent Mϕs show a highly stimulatory activity typical for M1 Mϕs, M-CSF-dependent Mϕs, marked by folate receptor β (FRβ, adopt an immunosuppressive M2 phenotype. We find the latter to be caused by the purinergic pathway that directs release of extracellular ATP and its conversion to immunosuppressive adenosine by co-expressed CD39 and CD73. Since we observed a misbalance between immunosuppressive and immunostimulatory Mϕs in human and murine arthritic joints, we devised a new strategy for RA treatment based on targeted delivery of a novel methotrexate (MTX formulation to the immunosuppressive FRβ+CD39+CD73+ Mϕs, which boosts adenosine production and curtails the dominance of proinflammatory Mϕs. In contrast to untargeted MTX, this approach leads to potent alleviation of inflammation in the murine arthritis model. In conclusion, we define the Mϕ extracellular purine metabolism as a novel checkpoint in Mϕ cell fate decision-making and an attractive target to control pathological Mϕs in immune-mediated diseases.

Macrophage/epithelium cross-talk regulates cell cycle progression and migration in pancreatic progenitors.

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Kristin Mussar

Full Text Available Macrophages populate the mesenchymal compartment of all organs during embryogenesis and have been shown to support tissue organogenesis and regeneration by regulating remodeling of the extracellular microenvironment. Whether this mesenchymal component can also dictate select developmental decisions in epithelia is unknown. Here, using the embryonic pancreatic epithelium as model system, we show that macrophages drive the epithelium to execute two developmentally important choices, i.e. the exit from cell cycle and the acquisition of a migratory phenotype. We demonstrate that these developmental decisions are effectively imparted by macrophages activated toward an M2 fetal-like functional state, and involve modulation of the adhesion receptor NCAM and an uncommon "paired-less" isoform of the transcription factor PAX6 in the epithelium. Over-expression of this PAX6 variant in pancreatic epithelia controls both cell motility and cell cycle progression in a gene-dosage dependent fashion. Importantly, induction of these phenotypes in embryonic pancreatic transplants by M2 macrophages in vivo is associated with an increased frequency of endocrine-committed cells emerging from ductal progenitor pools. These results identify M2 macrophages as key effectors capable of coordinating epithelial cell cycle withdrawal and cell migration, two events critical to pancreatic progenitors' delamination and progression toward their differentiated fates.

Macrophage/epithelium cross-talk regulates cell cycle progression and migration in pancreatic progenitors.

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Mussar, Kristin; Tucker, Andrew; McLennan, Linsey; Gearhart, Addie; Jimenez-Caliani, Antonio J; Cirulli, Vincenzo; Crisa, Laura

2014-01-01

Macrophages populate the mesenchymal compartment of all organs during embryogenesis and have been shown to support tissue organogenesis and regeneration by regulating remodeling of the extracellular microenvironment. Whether this mesenchymal component can also dictate select developmental decisions in epithelia is unknown. Here, using the embryonic pancreatic epithelium as model system, we show that macrophages drive the epithelium to execute two developmentally important choices, i.e. the exit from cell cycle and the acquisition of a migratory phenotype. We demonstrate that these developmental decisions are effectively imparted by macrophages activated toward an M2 fetal-like functional state, and involve modulation of the adhesion receptor NCAM and an uncommon "paired-less" isoform of the transcription factor PAX6 in the epithelium. Over-expression of this PAX6 variant in pancreatic epithelia controls both cell motility and cell cycle progression in a gene-dosage dependent fashion. Importantly, induction of these phenotypes in embryonic pancreatic transplants by M2 macrophages in vivo is associated with an increased frequency of endocrine-committed cells emerging from ductal progenitor pools. These results identify M2 macrophages as key effectors capable of coordinating epithelial cell cycle withdrawal and cell migration, two events critical to pancreatic progenitors' delamination and progression toward their differentiated fates.

β-Glucan from Lentinus edodes inhibits nitric oxide and tumor necrosis factor-α production and phosphorylation of mitogen-activated protein kinases in lipopolysaccharide-stimulated murine RAW 264.7 macrophages.

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Xu, Xiaojuan; Yasuda, Michiko; Nakamura-Tsuruta, Sachiko; Mizuno, Masashi; Ashida, Hitoshi

2012-01-06

Lentinan (LNT), a β-glucan from the fruiting bodies of Lentinus edodes, is well known to have immunomodulatory activity. NO and TNF-α are associated with many inflammatory diseases. In this study, we investigated the effects of LNT extracted by sonication (LNT-S) on the NO and TNF-α production in LPS-stimulated murine RAW 264.7 macrophages. The results suggested that treatment with LNT-S not only resulted in the striking inhibition of TNF-α and NO production in LPS-activated macrophage RAW 264.7 cells, but also the protein expression of inducible NOS (iNOS) and the gene expression of iNOS mRNA and TNF-α mRNA. It is surprising that LNT-S enhanced LPS-induced NF-κB p65 nuclear translocation and NF-κB luciferase activity, but severely inhibited the phosphorylation of JNK1/2 and ERK1/2. The neutralizing antibodies of anti-Dectin-1 and anti-TLR2 hardly affected the inhibition of NO production. All of these results suggested that the suppression of LPS-induced NO and TNF-α production was at least partially attributable to the inhibition of JNK1/2 and ERK1/2 activation. This work discovered a promising molecule to control the diseases associated with overproduction of NO and TNF-α.

Angiopoietin-like protein 2 induces proinflammatory responses in peritoneal cells

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Umikawa, Masato, E-mail: umikawa@med.u-ryukyu.ac.jp [Department of Medical Biochemistry, Graduate School of Medicine, University of the Ryukyus, Okinawa (Japan); Umikawa, Asako; Asato, Tsuyoshi; Takei, Kimiko [Department of Medical Biochemistry, Graduate School of Medicine, University of the Ryukyus, Okinawa (Japan); Matsuzaki, Goro [Department of Tropical Infectious Diseases, COMB, Tropical Biosphere Research Center, University of the Ryukyus, Okinawa (Japan); Kariya, Ken-ichi [Department of Medical Biochemistry, Graduate School of Medicine, University of the Ryukyus, Okinawa (Japan); Zhang, Cheng Cheng, E-mail: alec.zhang@utsouthwestern.edu [Department of Physiology, University of Texas Southwestern Medical Center, Dallas, TX (United States)

2015-11-13

Monocytes and macrophages are important effectors and regulators of inflammation, and both their differentiation and activation are regulated strictly in response to environmental cues. Angiopoietin-like protein 2 (Angptl2) is a multifaceted protein, displaying many physiological and pathological functions in inflammation, angiogenesis, hematopoiesis, and tumor development. Although recent studies implicate Angptl2 in chronic inflammation, the mechanisms of inflammation caused by Angptl2 remain unclear. The purpose of the present study was to elucidate the role of Angptl2 in inflammation by understanding the effects of Angptl2 on monocytes/macrophages. We showed that Angptl2 directly activates resident murine peritoneal monocytes and macrophages and induces a drastic upregulation of the transcription of several inflammatory genes including nitric oxide synthase 2 and prostaglandin-endoperoxide synthase 2, and several proinflammatory cytokine genes such as interleukin (IL)-1β, IL-6, TNFα, and CSF2, along with activation of ERK, JNK, p38, and nuclear factor kappa B signaling pathways. Concordantly, proinflammatory cytokines IL-1β, IL-6, TNFα, and GM-CSF, were rapidly elevated from murine peritoneal monocytes and macrophages. These results demonstrate a novel role for Angptl2 in inflammation via the direct activation of peritoneal monocytes and macrophages. - Highlights: • Angptl2 directly activates resident murine peritoneal monocytes and macrophages. • Angptl2 induces a drastic upregulation of expression of inflammatory genes. • Angptl2 induces activation of ERK, JNK, p38, and nuclear factor kappa B signaling pathways. • Angptl2 does not activate bone marrow derived macrophages or macrophage cell lines.

M2 macrophages activate WNT signaling pathway in epithelial cells: relevance in ulcerative colitis.

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Jesús Cosín-Roger

Full Text Available Macrophages, which exhibit great plasticity, are important components of the inflamed tissue and constitute an essential element of regenerative responses. Epithelial Wnt signalling is involved in mechanisms of proliferation and differentiation and expression of Wnt ligands by macrophages has been reported. We aim to determine whether the macrophage phenotype determines the expression of Wnt ligands, the influence of the macrophage phenotype in epithelial activation of Wnt signalling and the relevance of this pathway in ulcerative colitis. Human monocyte-derived macrophages and U937-derived macrophages were polarized towards M1 or M2 phenotypes and the expression of Wnt1 and Wnt3a was analyzed by qPCR. The effects of macrophages and the role of Wnt1 were analyzed on the expression of β-catenin, Tcf-4, c-Myc and markers of cell differentiation in a co-culture system with Caco-2 cells. Immunohistochemical staining of CD68, CD206, CD86, Wnt1, β-catenin and c-Myc were evaluated in the damaged and non-damaged mucosa of patients with UC. We also determined the mRNA expression of Lgr5 and c-Myc by qPCR and protein levels of β-catenin by western blot. Results show that M2, and no M1, activated the Wnt signaling pathway in co-culture epithelial cells through Wnt1 which impaired enterocyte differentiation. A significant increase in the number of CD206+ macrophages was observed in the damaged mucosa of chronic vs newly diagnosed patients. CD206 immunostaining co-localized with Wnt1 in the mucosa and these cells were associated with activation of canonical Wnt signalling pathway in epithelial cells and diminution of alkaline phosphatase activity. Our results show that M2 macrophages, and not M1, activate Wnt signalling pathways and decrease enterocyte differentiation in co-cultured epithelial cells. In the mucosa of UC patients, M2 macrophages increase with chronicity and are associated with activation of epithelial Wnt signalling and diminution in

Highly efficient gene transfer using a retroviral vector into murine T cells for preclinical chimeric antigen receptor-expressing T cell therapy

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Kusabuka, Hotaka; Fujiwara, Kento; Tokunaga, Yusuke; Hirobe, Sachiko; Nakagawa, Shinsaku; Okada, Naoki

2016-01-01

Adoptive immunotherapy using chimeric antigen receptor-expressing T (CAR-T) cells has attracted attention as an efficacious strategy for cancer treatment. To prove the efficacy and safety of CAR-T cell therapy, the elucidation of immunological mechanisms underlying it in mice is required. Although a retroviral vector (Rv) is mainly used for the introduction of CAR to murine T cells, gene transduction efficiency is generally less than 50%. The low transduction efficiency causes poor precision in the functional analysis of CAR-T cells. We attempted to improve the Rv gene transduction protocol to more efficiently generate functional CAR-T cells by optimizing the period of pre-cultivation and antibody stimulation. In the improved protocol, gene transduction efficiency to murine T cells was more than 90%. In addition, almost all of the prepared murine T cells expressed CAR after puromycin selection. These CAR-T cells had antigen-specific cytotoxic activity and secreted multiple cytokines by antigen stimulation. We believe that our optimized gene transduction protocol for murine T cells contributes to the advancement of T cell biology and development of immunotherapy using genetically engineered T cells. - Highlights: • We established highly efficient gene transduction protocols for murine T cells. • CD8"+ CAR-T cells had antigen-specific cytotoxic activity. • CD4"+ CAR-T cells secreted multiple cytokines by antigen stimulation. • This finding can contribute to the development of T-cell biology and immunotherapy.

Highly efficient gene transfer using a retroviral vector into murine T cells for preclinical chimeric antigen receptor-expressing T cell therapy

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Kusabuka, Hotaka; Fujiwara, Kento; Tokunaga, Yusuke; Hirobe, Sachiko; Nakagawa, Shinsaku, E-mail: nakagawa@phs.osaka-u.ac.jp; Okada, Naoki, E-mail: okada@phs.osaka-u.ac.jp

2016-04-22

Adoptive immunotherapy using chimeric antigen receptor-expressing T (CAR-T) cells has attracted attention as an efficacious strategy for cancer treatment. To prove the efficacy and safety of CAR-T cell therapy, the elucidation of immunological mechanisms underlying it in mice is required. Although a retroviral vector (Rv) is mainly used for the introduction of CAR to murine T cells, gene transduction efficiency is generally less than 50%. The low transduction efficiency causes poor precision in the functional analysis of CAR-T cells. We attempted to improve the Rv gene transduction protocol to more efficiently generate functional CAR-T cells by optimizing the period of pre-cultivation and antibody stimulation. In the improved protocol, gene transduction efficiency to murine T cells was more than 90%. In addition, almost all of the prepared murine T cells expressed CAR after puromycin selection. These CAR-T cells had antigen-specific cytotoxic activity and secreted multiple cytokines by antigen stimulation. We believe that our optimized gene transduction protocol for murine T cells contributes to the advancement of T cell biology and development of immunotherapy using genetically engineered T cells. - Highlights: • We established highly efficient gene transduction protocols for murine T cells. • CD8{sup +} CAR-T cells had antigen-specific cytotoxic activity. • CD4{sup +} CAR-T cells secreted multiple cytokines by antigen stimulation. • This finding can contribute to the development of T-cell biology and immunotherapy.

Quantitative GPCR and ion channel transcriptomics in primary alveolar macrophages and macrophage surrogates

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Groot-Kormelink Paul J

2012-10-01

Full Text Available Abstract Background Alveolar macrophages are one of the first lines of defence against invading pathogens and play a central role in modulating both the innate and acquired immune systems. By responding to endogenous stimuli within the lung, alveolar macrophages contribute towards the regulation of the local inflammatory microenvironment, the initiation of wound healing and the pathogenesis of viral and bacterial infections. Despite the availability of protocols for isolating primary alveolar macrophages from the lung these cells remain recalcitrant to expansion in-vitro and therefore surrogate cell types, such as monocyte derived macrophages and phorbol ester-differentiated cell lines (e.g. U937, THP-1, HL60 are frequently used to model macrophage function. Methods The availability of high throughput gene expression technologies for accurate quantification of transcript levels enables the re-evaluation of these surrogate cell types for use as cellular models of the alveolar macrophage. Utilising high-throughput TaqMan arrays and focussing on dynamically regulated families of integral membrane proteins, we explore the similarities and differences in G-protein coupled receptor (GPCR and ion channel expression in alveolar macrophages and their widely used surrogates. Results The complete non-sensory GPCR and ion channel transcriptome is described for primary alveolar macrophages and macrophage surrogates. The expression of numerous GPCRs and ion channels whose expression were hitherto not described in human alveolar macrophages are compared across primary macrophages and commonly used macrophage cell models. Several membrane proteins known to have critical roles in regulating macrophage function, including CXCR6, CCR8 and TRPV4, were found to be highly expressed in macrophages but not expressed in PMA-differentiated surrogates. Conclusions The data described in this report provides insight into the appropriate choice of cell models for

Activation of Murine Macrophages by Lipoprotein and Lipooligosaccharide of Treponema denticola

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Rosen, Graciela; Sela, Michael N.; Naor, Ronit; Halabi, Amal; Barak, Vivian; Shapira, Lior

1999-01-01

We have recently demonstrated that the periodontopathogenic oral spirochete Treponema denticola possesses membrane-associated lipoproteins in addition to lipooligosaccharide (LOS). The aim of the present study was to test the potential of these oral spirochetal components to induce the production of inflammatory mediators by human macrophages, which in turn may stimulate tissue breakdown as observed in periodontal diseases. An enriched lipoprotein fraction (dLPP) from T. denticola ATCC 35404 obtained upon extraction of the treponemes with Triton X-114 was found to stimulate the production of nitric oxide (NO), tumor necrosis factor alpha (TNF-α), and interleukin-1 (IL-1) by mouse macrophages in a dose-dependent manner. Induction of NO by dLPP was at 25% of the levels obtained by Salmonella typhosa lipopolysaccharide (LPS) at similar concentrations, while IL-1 was produced at similar levels by both inducers. dLPP-mediated macrophage activation was unaffected by amounts of polymyxin B that neutralized the induction produced by S. typhosa LPS. dLPP also induced NO and TNF-α secretion from macrophages isolated from endotoxin-unresponsive C3H/HeJ mice to an extent similar to the stimulation produced in endotoxin-responsive mice. Purified T. denticola LOS also produced a concentration-dependent activation of NO and TNF-α in LPS-responsive and -nonresponsive mouse macrophages. However, macrophage activation by LOS was inhibited by polymyxin B. These results suggest that T. denticola lipoproteins and LOS may play a role in the inflammatory processes that characterize periodontal diseases. PMID:10024558

Inhibition of P-glycoprotein by HIV protease inhibitors increases intracellular accumulation of berberine in murine and human macrophages.

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Weibin Zha

Full Text Available HIV protease inhibitor (PI-induced inflammatory response in macrophages is a major risk factor for cardiovascular diseases. We have previously reported that berberine (BBR, a traditional herbal medicine, prevents HIV PI-induced inflammatory response through inhibiting endoplasmic reticulum (ER stress in macrophages. We also found that HIV PIs significantly increased the intracellular concentrations of BBR in macrophages. However, the underlying mechanisms of HIV PI-induced BBR accumulation are unknown. This study examined the role of P-glycoprotein (P-gp in HIV PI-mediated accumulation of BBR in macrophages.Cultured mouse RAW264.7 macrophages, human THP-1-derived macrophages, Wild type MDCK (MDCK/WT and human P-gp transfected (MDCK/P-gp cells were used in this study. The intracellular concentration of BBR was determined by HPLC. The activity of P-gp was assessed by measuring digoxin and rhodamine 123 (Rh123 efflux. The interaction between P-gp and BBR or HIV PIs was predicated by Glide docking using Schrodinger program. The results indicate that P-gp contributed to the efflux of BBR in macrophages. HIV PIs significantly increased BBR concentrations in macrophages; however, BBR did not alter cellular HIV PI concentrations. Although HIV PIs did not affect P-gp expression, P-gp transport activities were significantly inhibited in HIV PI-treated macrophages. Furthermore, the molecular docking study suggests that both HIV PIs and BBR fit the binding pocket of P-gp, and HIV PIs may compete with BBR to bind P-gp.HIV PIs increase the concentration of BBR by modulating the transport activity of P-gp in macrophages. Understanding the cellular mechanisms of potential drug-drug interactions is critical prior to applying successful combinational therapy in the clinic.

Interaction with Epithelial Cells Modifies Airway Macrophage Response to Ozone

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The initial innate immune response to ozone (03) in the lung is orchestrated by structural cells, such as epithelial cells, and resident immune cells, such as airway macrophages (Macs). We developed an epithelial cell-Mac coculture model to investigate how epithelial cell-derived...

Role of tumor necrosis factor in macrophage leishmanicidal activity in vitro and resistance to cutaneous leishmaniasis in vivo.

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Theodos, C M; Povinelli, L; Molina, R; Sherry, B; Titus, R G

1991-01-01

Recombinant human tumor necrosis factor (TNF) and purified murine TNF were both able to activate macrophages to destroy intracellular Leishmania major in vitro. In addition, parasitizing macrophages with L. major markedly increased the ability of the cells to produce TNF. Finally, when mice were vaccinated with an avirulent form of L. major, the animals produced large amounts of TNF but no gamma interferon in response to infection with virulent L. major. Treating these mice with a neutralizing anti-TNF antibody led to partial but not complete inhibition of the resistant state, which suggests that factors other than TNF and gamma interferon contribute to resistance to L. major. PMID:1906844

Comparison of the suppressor cells found in the spleens of 89Sr-treated mice and in normal murine bone marrow

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Levy, E.M.; Corvese, J.S.; Bennett, M.

1981-01-01

Normal murine bone marrow cells and spleen cells of mice treated with 89 Sr both have suppressive activity. These nonspecific suppressor cells inhibit the ability of normal spleen cells to undergo antibody responses in vitro. After being precultured for 24 hr, these cells will also suppress antibody responses in vivo and the responses of normal spleen cells to T and B cell mitogens in vitro. These cells have previously been shown not to be mature T or B lymphocytes or macrophages. Velocity sedimentation and cell-size analysis indicated that both suppressor cells are large (approx. =206 μ 3 ). Mitomycin C treatment eliminated the ability of both suppressor cells to inhibit an in vitro antibody response. In contrast, this treatment did not reduce the ability of the cells to inhibit an in vitro antibody response. In contrast, this treatment did not reduce the ability of the cells to suppress a mitogenic response. Irradiation (1000 R) was also ineffective in eliminating the ability of either cell to suppress a mitogenic response. We conclude that the 2 suppressor cells are closely related if not identical, and we speculate that these cells may function in vivo to suppress immune reactivity in areas of intense hematopoiesis

Acquisition of repertoires of suppressor T cells under the influence of macrophages

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Soejima, T.; Nagayama, A.; Sado, T.; Taniguchi, M.

1988-01-01

Acquisition of repertoires and genetic restriction specificities of suppressor T cells (Ts) and their factors were studied by using full allogeneic radiation bone marrow chimera and H-2 congenic pairs, B10.A(3R) and B10.A(5R), which received conventional or cloned macrophages by cell transfer. Suppressor T-cell factor (TsF) from C3H----C57BL/6 or C57BL/6----C3H chimera suppressed only donor but not host-type responses of either C3H or C57BL/6, in an antigen-specific fashion. However, if chimera mice were given conventional or cloned macrophages of the host type, the chimera TsF in turn suppressed both the responses of C3H and C57BL/6 mice but not those of the third party, BALB/c, indicating that macrophages are responsible for the acquisition of host restriction specificity. Similarly, B10.A(5R) mice developed I-Jb restricted Ts or TsF when the B10.A(3R) macrophage cell line was injected at the time of antigen priming. The reverse was also true. B10.A(3R) mice did generate I-Jk restricted Ts when they received the B10.A(5R) macrophage cell line. Thus, the results clearly demonstrated that B10.A(3R) or B10.A(5R) mice potentially possessed their ability to express both I-Jk and I-Jb determinants and that repertoires and genetic restriction specificity of Ts and their TsF were acquired at a macrophage level at the time of antigen-priming

Carbon black nanoparticles induce type II epithelial cells to release chemotaxins for alveolar macrophages

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Donaldson Ken

2005-12-01

Full Text Available Abstract Background Alveolar macrophages are a key cell in dealing with particles deposited in the lungs and in determining the subsequent response to that particle exposure. Nanoparticles are considered a potential threat to the lungs and the mechanism of pulmonary response to nanoparticles is currently under intense scrutiny. The type II alveolar epithelial cell has previously been shown to release chemoattractants which can recruit alveolar macrophages to sites of particle deposition. The aim of this study was to assess the responses of a type II epithelial cell line (L-2 to both fine and nanoparticle exposure in terms of secretion of chemotactic substances capable of inducing macrophage migration. Results Exposure of type II cells to carbon black nanoparticles resulted in significant release of macrophage chemoattractant compared to the negative control and to other dusts tested (fine carbon black and TiO2 and nanoparticle TiO2 as measured by macrophage migration towards type II cell conditioned medium. SDS-PAGE analysis of the conditioned medium from particle treated type II cells revealed that a higher number of protein bands were present in the conditioned medium obtained from type II cells treated with nanoparticle carbon black compared to other dusts tested. Size-fractionation of the chemotaxin-rich supernatant determined that the chemoattractants released from the epithelial cells were between 5 and 30 kDa in size. Conclusion The highly toxic nature and reactive surface chemistry of the carbon black nanoparticles has very likely induced the type II cell line to release pro-inflammatory mediators that can potentially induce migration of macrophages. This could aid in the rapid recruitment of inflammatory cells to sites of particle deposition and the subsequent removal of the particles by phagocytic cells such as macrophages and neutrophils. Future studies in this area could focus on the exact identity of the substance(s released by the

Metabolic Plasticity of Stem Cells and Macrophages in Cancer

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Jelena Krstic

2017-08-01

Full Text Available In addition to providing essential molecules for the overall function of cells, metabolism plays an important role in cell fate and can be affected by microenvironmental stimuli as well as cellular interactions. As a specific niche, tumor microenvironment (TME, consisting of different cell types including stromal/stem cells and immune cells, is characterized by distinct metabolic properties. This review will be focused on the metabolic plasticity of mesenchymal stromal/stem cells (MSC and macrophages in TME, as well as on how the metabolic state of cancer stem cells (CSC, as key drivers of oncogenesis, affects their generation and persistence. Namely, heterogenic metabolic phenotypes of these cell populations, which include various levels of dependence on glycolysis or oxidative phosphorylation are closely linked to their complex roles in cancer progression. Besides well-known extrinsic factors, such as cytokines and growth factors, the differentiation and activation states of CSC, MSC, and macrophages are coordinated by metabolic reprogramming in TME. The significance of mutual metabolic interaction between tumor stroma and cancer cells in the immune evasion and persistence of CSC is currently under investigation.

Mycobacterium leprae-Infected Macrophages Preferentially Primed Regulatory T Cell Responses and Was Associated with Lepromatous Leprosy.

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Degang Yang

2016-01-01

Full Text Available The persistence of Mycobacterium leprae (M. leprae infection is largely dependent on the types of host immune responses being induced. Macrophage, a crucial modulator of innate and adaptive immune responses, could be directly infected by M. leprae. We therefore postulated that M. leprae-infected macrophages might have altered immune functions.Here, we treated monocyte-derived macrophages with live or killed M. leprae, and examined their activation status and antigen presentation. We found that macrophages treated with live M. leprae showed committed M2-like function, with decreased interleukin 1 beta (IL-1beta, IL-6, tumor necrosis factor alpha (TNF-alpha and MHC class II molecule expression and elevated IL-10 and CD163 expression. When incubating with naive T cells, macrophages treated with live M. leprae preferentially primed regulatory T (Treg cell responses with elevated FoxP3 and IL-10 expression, while interferon gamma (IFN-gamma expression and CD8+ T cell cytotoxicity were reduced. Chromium release assay also found that live M. leprae-treated macrophages were more resistant to CD8+ T cell-mediated cytotoxicity than sonicated M. leprae-treated monocytes. Ex vivo studies showed that the phenotype and function of monocytes and macrophages had clear differences between L-lep and T-lep patients, consistent with the in vitro findings.Together, our data demonstrate that M. leprae could utilize infected macrophages by two mechanisms: firstly, M. leprae-infected macrophages preferentially primed Treg but not Th1 or cytotoxic T cell responses; secondly, M. leprae-infected macrophages were more effective at evading CD8+ T cell-mediated cytotoxicity.

Mycobacterium leprae-Infected Macrophages Preferentially Primed Regulatory T Cell Responses and Was Associated with Lepromatous Leprosy.

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Yang, Degang; Shui, Tiejun; Miranda, Jake W; Gilson, Danny J; Song, Zhengyu; Chen, Jia; Shi, Chao; Zhu, Jianyu; Yang, Jun; Jing, Zhichun

2016-01-01

The persistence of Mycobacterium leprae (M. leprae) infection is largely dependent on the types of host immune responses being induced. Macrophage, a crucial modulator of innate and adaptive immune responses, could be directly infected by M. leprae. We therefore postulated that M. leprae-infected macrophages might have altered immune functions. Here, we treated monocyte-derived macrophages with live or killed M. leprae, and examined their activation status and antigen presentation. We found that macrophages treated with live M. leprae showed committed M2-like function, with decreased interleukin 1 beta (IL-1beta), IL-6, tumor necrosis factor alpha (TNF-alpha) and MHC class II molecule expression and elevated IL-10 and CD163 expression. When incubating with naive T cells, macrophages treated with live M. leprae preferentially primed regulatory T (Treg) cell responses with elevated FoxP3 and IL-10 expression, while interferon gamma (IFN-gamma) expression and CD8+ T cell cytotoxicity were reduced. Chromium release assay also found that live M. leprae-treated macrophages were more resistant to CD8+ T cell-mediated cytotoxicity than sonicated M. leprae-treated monocytes. Ex vivo studies showed that the phenotype and function of monocytes and macrophages had clear differences between L-lep and T-lep patients, consistent with the in vitro findings. Together, our data demonstrate that M. leprae could utilize infected macrophages by two mechanisms: firstly, M. leprae-infected macrophages preferentially primed Treg but not Th1 or cytotoxic T cell responses; secondly, M. leprae-infected macrophages were more effective at evading CD8+ T cell-mediated cytotoxicity.

Proteoglycan biosynthesis in murine monocytic leukemic (M1) cells before and after differentiation

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McQuillan, D.J.; Yanagishita, M.; Hascall, V.C.; Bickel, M.

1989-01-01

Murine monocytic leukemic (M1) cells were cultured in the presence of [ 3 H]glucosamine and [ 35 S]sulfate. Labeled proteoglycans were purified by anion exchange chromatography and characterized by gel filtration and sodium dodecyl sulfate-polyacrylamide gel electrophoresis in combination with chemical and enzymatic degradation. M1 cells synthesize a single predominant species of proteoglycan which distributes almost equally between the cell and medium after 17 h labeling. The cell-associated proteoglycan has an overall size of about 135 kDa and contains three to five chondroitin sulfate chains (28-31 kDa each) attached to a chondroitinase-generated core protein of 28 kDa. The synthesis and subsequent secretion of this proteoglycan was enhanced 4-5-fold in cells induced to differentiate into macrophages. This was not a phenomenon of arrest in the G0/G1 stage of the cell cycle, since density inhibited undifferentiated cells arrested at this stage did not increase proteoglycan synthesis. The chondroitin sulfate chains contained exclusively chondroitin 4- and 6-sulfate; however, the ratio of these two disaccharides differed between the medium- and cell-associated proteoglycans, and changed during progression of the cells into a fully differentiated phenotype. Pulse-chase kinetics indicate the presence of two distinct pools of proteoglycan; one that is secreted very rapidly from the cell after a approximately 1-h lag, and a second pool that is turned over in the cell with a half-time of approximately 3.5 h. Subtle differences in the glycosylation patterns of the medium- and cell-associated species are consistent with synthesis of two pools. Papain digestion suggests that the chondroitin sulfate chains are clustered on a small protease resistant peptide. The data suggest that this proteoglycan is similar to the serglycin proteoglycan family

Cord blood-derived macrophage-lineage cells rapidly stimulate osteoblastic maturation in mesenchymal stem cells in a glycoprotein-130 dependent manner.

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Tania J Fernandes

Full Text Available In bone, depletion of osteoclasts reduces bone formation in vivo, as does osteal macrophage depletion. How osteoclasts and macrophages promote the action of bone forming osteoblasts is, however, unclear. Since recruitment and differentiation of multi-potential stromal cells/mesenchymal stem cells (MSC generates new active osteoblasts, we investigated whether human osteoclasts and macrophages (generated from cord blood-derived hematopoietic progenitors induce osteoblastic maturation in adipose tissue-derived MSC. When treated with an osteogenic stimulus (ascorbate, dexamethasone and β-glycerophosphate these MSC form matrix-mineralising, alkaline phosphatase-expressing osteoblastic cells. Cord blood-derived progenitors were treated with macrophage colony stimulating factor (M-CSF to form immature proliferating macrophages, or with M-CSF plus receptor activator of NFκB ligand (RANKL to form osteoclasts; culture medium was conditioned for 3 days by these cells to study their production of osteoblastic factors. Both osteoclast- and macrophage-conditioned medium (CM greatly enhanced MSC osteoblastic differentiation in both the presence and absence of osteogenic medium, evident by increased alkaline phosphatase levels within 4 days and increased mineralisation within 14 days. These CM effects were completely ablated by antibodies blocking gp130 or oncostatin M (OSM, and OSM was detectable in both CM. Recombinant OSM very potently stimulated osteoblastic maturation of these MSC and enhanced bone morphogenetic protein-2 (BMP-2 actions on MSC. To determine the influence of macrophage activation on this OSM-dependent activity, CM was collected from macrophage populations treated with M-CSF plus IL-4 (to induce alternative activation or with GM-CSF, IFNγ and LPS to cause classical activation. CM from IL-4 treated macrophages stimulated osteoblastic maturation in MSC, while CM from classically-activated macrophages did not. Thus, macrophage-lineage cells

The role of PTEN in regulation of hepatic macrophages activation and function in progression and reversal of liver fibrosis

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Cheng, Yahui; Tian, Yuanyao; Xia, Jialu; Wu, Xiaoqin; Yang, Yang; Li, Xiaofeng; Huang, Cheng; Meng, Xiaoming; Ma, Taotao; Li, Jun, E-mail: lj@ahmu.edu.cn

2017-02-15

Activation of Kupffer cells (KCs) plays a pivotal role in the pathogenesis of liver fibrosis. The progression and reversal of CCl{sub 4}-induced mouse liver fibrosis showed a mixed induction of hepatic classical (M1) and alternative (M2) macrophage markers. Although the role of phosphatase and tensin homolog deleted on chromosome 10 (PTEN) in modulating myeloid cell activation has recently been identified, its function in macrophage activation during hepatic fibrosis remains to be fully appreciated. In our study, PTEN expression of KCs was remarkably decreased in CCl{sub 4}-induced mice but increased to a near-normal level in reversed mice. Moreover, PTEN was significantly decreased in IL4-induced RAW 264.7 cells in vitro and lower expression of PTEN was observed in M2 macrophages in vivo. In addition, loss- and gain-of-function studies suggested that PTEN regulates M2 macrophages polarization via activation of PI3K/Akt/STAT6 signaling, but had a limited effect on M1 macrophages polarization in vitro. Additionally, Ly294002, a chemical inhibitor of PI3K/Akt, could dramatically down-regulate the hallmarks of M2 macrophages. In conclusion, PTEN mediates macrophages activation by PI3K/Akt/STAT6 signaling pathway, which provides novel compelling evidences on the potential of PTEN in liver injury and opens new cellular target for the pharmacological therapy of liver fibrosis. - Highlights: • CCl{sub 4} treatment triggered a mixed M1/M2 macrophage phenotype in fibrosis. • Lower expression of PTEN in murine M2 macrophages in vivo and vitro. • PTEN modulates M2 macrophages activation via PI3K/Akt/STAT6 signaling. • Provide a new cellular target modulate macrophage mediated hepatic fibrosis.

Human cytochrome c enters murine J774 cells and causes G1 and G2/M cell cycle arrest and induction of apoptosis

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Hiraoka, Yoshinori; Granja, Ana Teresa; Fialho, Arsenio M.; Schlarb-Ridley, Beatrix G.; Das Gupta, Tapas K.; Chakrabarty, Ananda M.; Yamada, Tohru

2005-01-01

Cytochrome c is well known as a carrier of electrons during respiration. Current evidence indicates that cytochrome c also functions as a major component of apoptosomes to induce apoptosis in eukaryotic cells as well as an antioxidant. More recently, a prokaryotic cytochrome c, cytochrome c 551 from Pseudomonas aeruginosa, has been shown to enter in mammalian cells such as the murine macrophage-like J774 cells and causes inhibition of cell cycle progression. Much less is known about such functions by mammalian cytochromes c, particularly the human cytochrome c. We now report that similar to P. aeruginosa cytochrome c 551 , the purified human cytochrome c protein can enter J774 cells and induce cell cycle arrest at the G 1 to S phase, as well as at the G 2 /M phase at higher concentrations. Unlike P. aeruginosa cytochrome c 551 which had no effect on the induction of apoptosis, human cytochrome c induces significant apoptosis and cell death in J774 cells, presumably through inhibition of the cell cycle at the G 2 /M phase. When incubated with human breast cancer MCF-7 and normal mammary epithelial cell line MCF-10A1 cells, human cytochrome c entered in both types of cells but induced cell death only in the normal MCF-10A1 cells. The ability of human cytochrome c to enter J774 cells was greatly reduced at 4 deg. C, suggesting energy requirement in the entry process

Nanopatterned bulk metallic glass-based biomaterials modulate macrophage polarization.

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Shayan, Mahdis; Padmanabhan, Jagannath; Morris, Aaron H; Cheung, Bettina; Smith, Ryan; Schroers, Jan; Kyriakides, Themis R

2018-06-01

Polarization of macrophages by chemical, topographical and mechanical cues presents a robust strategy for designing immunomodulatory biomaterials. Here, we studied the ability of nanopatterned bulk metallic glasses (BMGs), a new class of metallic biomaterials, to modulate murine macrophage polarization. Cytokine/chemokine analysis of IL-4 or IFNγ/LPS-stimulated macrophages showed that the secretion of TNF-α, IL-1α, IL-12, CCL-2 and CXCL1 was significantly reduced after 24-hour culture on BMGs with 55 nm nanorod arrays (BMG-55). Additionally, under these conditions, macrophages increased phagocytic potential and exhibited decreased cell area with multiple actin protrusions. These in vitro findings suggest that nanopatterning can modulate biochemical cues such as IFNγ/LPS. In vivo evaluation of the subcutaneous host response at 2 weeks demonstrated that the ratio of Arg-1 to iNOS increased in macrophages adjacent to BMG-55 implants, suggesting modulation of polarization. In addition, macrophage fusion and fibrous capsule thickness decreased and the number and size of blood vessels increased, which is consistent with changes in macrophage responses. Our study demonstrates that nanopatterning of BMG implants is a promising technique to selectively polarize macrophages to modulate the immune response, and also presents an effective tool to study mechanisms of macrophage polarization and function. Implanted biomaterials elicit a complex series of tissue and cellular responses, termed the foreign body response (FBR), that can be influenced by the polarization state of macrophages. Surface topography can influence polarization, which is broadly characterized as either inflammatory or repair-like. The latter has been linked to improved outcomes of the FBR. However, the impact of topography on macrophage polarization is not fully understood, in part, due to a lack of high moduli biomaterials that can be reproducibly processed at the nanoscale. Here, we studied

The cellular prion protein negatively regulates phagocytosis and cytokine expression in murine bone marrow-derived macrophages.

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Min Wang

Full Text Available The cellular prion protein (PrP(C is a glycosylphosphatidylinositol (GPI-anchored glycoprotein on the cell surface. Previous studies have demonstrated contradictory roles for PrP(C in connection with the phagocytic ability of macrophages. In the present work, we investigated the function of PrP(C in phagocytosis and cytokine expression in bone marrow-derived macrophages infected with Escherichia coli. E. coli infection induced an increase in the PRNP mRNA level. Knockout of PrP(C promoted bacterial uptake; upregulated Rab5, Rab7, and Eea1 mRNA expression; and increased the recruitment of lysosomal-associated membrane protein-2 to phagosomes, suggesting enhanced microbicidal activity. Remarkably, knockout of PrP(C suppressed the proliferation of internalized bacteria and increased the expression of cytokines such as interleukin-1β. Collectively, our data reveal an important role of PrP(C as a negative regulator for phagocytosis, phagosome maturation, cytokine expression, and macrophage microbicidal activity.

Anthocyanins from black rice (Oryza sativa) promote immune responses in leukemia through enhancing phagocytosis of macrophages in vivo.

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Fan, Ming-Jen; Yeh, Ping-Hsuan; Lin, Jing-Pin; Huang, An-Cheng; Lien, Jin-Cherng; Lin, Hui-Yi; Chung, Jing-Gung

2017-07-01

Rice is a staple food in numerous countries around the world. Anthocyanins found in black rice have been reported to reduce the risk of certain diseases, but the effects of crude extract of anthocyanins from Asia University-selected purple glutinous indica rice (AUPGA) on immune responses have not yet been demonstrated. The current study aimed to investigate whether AUPGA treatment could affect immune responses in murine leukemia cells in vivo . Murine acute myelomonocytic leukemia WEHI-3 cells were intraperitoneally injected into normal BALB/c mice to generate leukemia mice. A total of 50 mice were randomly divided into five groups (n=10 in each group) and were fed a diet supplemented with AUPGA at 0, 20, 50 or 100 mg/kg for three weeks. All mice were weighed and the blood, liver and spleen were collected for further experiments. The results indicated that AUPGA did not significantly affect animal body weight, but significantly increased spleen weight (P<0.05) and decreased liver weight (P<0.05) when compared with the control group. AUPGA significantly increased the T cell (CD3) population at treatments of 20 and 100 mg/kg (P<0.05). However, it only significantly increased the B cell (CD19) population at a treatment of 20 mg/kg (P<0.05). Furthermore, AUPGA at 50 and 100 mg/kg significantly increased the monocyte (CD11b) population and the level of macrophages (Mac-3; P<0.05 for both). AUPGA at 50 and 100 mg/kg significantly promoted macrophage phagocytosis in peripheral blood mononuclear cells (P<0.05), and all doses of AUPGA treatment significantly promoted macrophage phagocytotic activity in the peritoneum (P<0.05). AUPGA treatment significantly decreased natural killer cell activity from splenocytes (P<0.05). Finally, AUPGA treatment at 20 mg/kg treatment significantly promoted T cell proliferation (P<0.05), and treatment at 50 and 100 mg/kg significantly decreased B cell proliferation compared with the control group (P<0.05).