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Sample records for activated peritoneal macrophages

  1. Peritonitis-induced antitumor activity of peritoneal macrophages from uremic patients.

    PubMed

    Turyna, Bohdan; Jurek, Aleksandra; Gotfryd, Kamil; Siaśkiewicz, Agnieszka; Kubit, Piotr; Klein, Andrzej

    2004-01-01

    The macrophages belong to the effector cells of both nonspecific and specific immune response. These cells generally express little cytotoxicity unless activated. The present work was intended to determine if peritoneal macrophages collected from patients on Continuous Ambulatory Peritoneal Dialysis (CAPD) during episodes of peritonitis were active against human tumor cell lines without further in vitro stimulation. We also compared macrophage antitumor potential with effectiveness of drugs used in cancer therapy (taxol and suramin). Conditioned medium (CM) of macrophages collected during inflammation-free periods did not exhibit cytostatic and cytotoxic activity against both tumor (A549 and HTB44) and non-transformed (BEAS-2B and CRL2190) cells. Exposure of tumor cells to CM of macrophages harvested during peritonitis resulted in significant suppression of proliferation, impairment of viability and induction of apoptosis, in contrast to non-transformed cells, which remained unaffected. The efficacy of CM of inflammatory macrophages as an antitumor agent appeared to be comparable to cytostatic and cytotoxic potency of taxol and suramin or, in the case of HTB44 cells, even higher. The results obtained suggest that activated human macrophages might represent a useful tool for cancer immunotherapy.

  2. Immunomodulation by Blastomyces dermatitidis: functional activity of murine peritoneal macrophages.

    PubMed Central

    McDaniel, L S; Cozad, G C

    1983-01-01

    Cell-mediated immunity plays the dominant role in the immune response of mice to Blastomyces dermatitidis infections. Since macrophages play an important role in cell-mediated immunity, the interactions between sensitized murine peritoneal macrophages and the yeast phase of B. dermatitidis were investigated. Scanning electron microscopy showed that the sensitized macrophages readily phagocytized B. dermatitidis yeast cells. In addition, there appeared to be activation of metabolic pathways within the sensitized macrophages, as indicated by increased chemiluminescence activity during phagocytosis. Sensitized macrophages were significantly better at controlling intracellular proliferation of the yeast cells when compared to nonsensitized cells. This was determined by disruption of macrophages and plating for viable yeasts. Scanning electron microscope observations offered further substantiation. Experiments with Candida albicans indicated that B. dermatitidis non-specifically activated macrophages. At 2 h postphagocytosis, 30% fewer C. albicans in B. dermatitidis-activated macrophages were able to form germ tubes. These studies demonstrated the multiple potential of activated macrophages with regard to their functional activity. Images PMID:6840859

  3. Effect of lipopolysaccharide on protein accumulation by murine peritoneal macrophages: the correlation to activation for macrophage tumoricidal function

    SciTech Connect

    Tannenbaum, C.S.

    1987-01-01

    The protein synthetic patterns of tumoricidal murine peritoneal macrophage populations have been compared to those of non-tumoricidal populations utilizing two dimensional polyacrylamide gel electrophoresis (2D PAGE) of (/sup 35/S)-methionine-labeled proteins. While the protein synthetic patterns exhibited by resident, inflammatory and activated macrophages had numerous common features which distinguished them from the other normal non-macrophage cell types examined, unique proteins also distinguished each macrophage population from the others. Peritoneal macrophages elicited by treatment with heat killed Propionibacterium acnes, the live, attenuated Mycobacterium bovis strain BCG, Listeria monocytogenes and the protozoan flagellate Trypanosoma rhodesiense, all exhibited tumoricidal activity in 16h or 72h functional assays, and shared a common protein synthetic profile which differentiated them from the synthetic patterns characteristic of the non-tumoricidal resident and inflammatory macrophages.

  4. The Immunomodulatory Activity of Jacaric Acid, a Conjugated Linolenic Acid Isomer, on Murine Peritoneal Macrophages

    PubMed Central

    Liu, Wai Nam; Leung, Kwok Nam

    2015-01-01

    This study aims at demonstrating the immunomodulatory property of jacaric acid, a conjugated linolenic acid (CLNA) isomer that is present in jacaranda seed oil, on murine peritoneal macrophages. Our results showed that jacaric acid exhibited no significant cytotoxicity on the thioglycollate-elicited murine peritoneal macrophages as revealed by the neutral red uptake assay, but markedly increased their cytostatic activity on the T-cell lymphoma MBL-2 cells as measured by the fluorometric CyQuant® NF Cell Proliferation Assay Kit. Flow cytometric analysis indicated that jacaric acid could enhance the endocytic activity of macrophages and elevated their intracellular production of superoxide anion. Moreover, jacaric acid-treated macrophages showed an increase in the production of nitric oxide which was accompanied by an increase in the expression level of inducible nitric oxide synthase protein. In addition, the secretion of several pro-inflammatory cytokines, including interferon-γ, interleukin-1β and tumor necrosis factor-α, was up-regulated. Collectively, our results indicated that the naturally-occurring CLNA isomer, jacaric acid, could exhibit immunomodulating activity on the murine peritoneal macrophages in vitro, suggesting that this CLNA isomer may act as an immunopotentiator which can be exploited for the treatment of some immunological disorders with minimal toxicity and fewer side effects. PMID:26629697

  5. The Immunomodulatory Activity of Jacaric Acid, a Conjugated Linolenic Acid Isomer, on Murine Peritoneal Macrophages.

    PubMed

    Liu, Wai Nam; Leung, Kwok Nam

    2015-01-01

    This study aims at demonstrating the immunomodulatory property of jacaric acid, a conjugated linolenic acid (CLNA) isomer that is present in jacaranda seed oil, on murine peritoneal macrophages. Our results showed that jacaric acid exhibited no significant cytotoxicity on the thioglycollate-elicited murine peritoneal macrophages as revealed by the neutral red uptake assay, but markedly increased their cytostatic activity on the T-cell lymphoma MBL-2 cells as measured by the fluorometric CyQuant® NF Cell Proliferation Assay Kit. Flow cytometric analysis indicated that jacaric acid could enhance the endocytic activity of macrophages and elevated their intracellular production of superoxide anion. Moreover, jacaric acid-treated macrophages showed an increase in the production of nitric oxide which was accompanied by an increase in the expression level of inducible nitric oxide synthase protein. In addition, the secretion of several pro-inflammatory cytokines, including interferon-γ, interleukin-1β and tumor necrosis factor-α, was up-regulated. Collectively, our results indicated that the naturally-occurring CLNA isomer, jacaric acid, could exhibit immunomodulating activity on the murine peritoneal macrophages in vitro, suggesting that this CLNA isomer may act as an immunopotentiator which can be exploited for the treatment of some immunological disorders with minimal toxicity and fewer side effects.

  6. Selective induction of metabolic activation programs in peritoneal macrophages by lipopolysaccharide substructures.

    PubMed Central

    Lehmann, V; Benninghoff, B; Dröge, W

    1991-01-01

    The structural elements of Salmonella typhimurium lipopolysaccharides (LPS) that are able to stimulate peritoneal macrophages to produce increased amounts of prostaglandin E2, ornithine, and citrulline, agents known to modulate immune responses, are described. Two different incomplete lipid A structures which lack the carbohydrate portion, the nonhydroxylated fatty acids lauric acid and myristic acid (lipid A precursor IB), and additional palmitic acid (lipid A precursor IA) stimulated increased prostaglandin E2 synthesis but were unable to augment ornithine and citrulline production at concentrations of up to 0.5 microgram/ml. Acyl-deficient smooth LPS containing lipid A precursors IA and IB substituted by the complete carbohydrate region were able to augment prostaglandin E2 and ornithine production but failed, even at a high concentration (0.5 microgram/ml), to stimulate citrulline production. Moreover, Re glycolipids and smooth intact LPS containing the lipid A region with 3-acyloxyacyl residues possessed all of the structural requirements to induce increased prostaglandin E2, ornithine, and citrulline synthesis. Finally, all of the LPS structures, including lipid A precursors IA and IB stimulated, in combination with gamma interferon, production of citrulline with similar efficiencies. These results demonstrate that LPS contains various substructures including regions of the carbohydrate and lipid A structure that can deliver signals for the activation of peritoneal macrophages. Signals for partial activation of macrophages to produce prostaglandins and ornithine can be delivered by acyl-deficient LPS structures. In contrast, full activation of macrophages to produce citrulline requires an additional signal that is delivered by 3-acyloxyacyl residues of the lipid A region or gamma interferon. PMID:1906843

  7. Aging Enhances the Production of Reactive Oxygen Species and Bactericidal Activity in Peritoneal Macrophages by Upregulating Classical Activation Pathways

    SciTech Connect

    Smallwood, Heather S.; López-Ferrer, Daniel; Squier, Thomas C.

    2011-10-07

    Maintenance of macrophages in their basal state and their rapid activation in response to pathogen detection are central to the innate immune system, acting to limit nonspecific oxidative damage and promote pathogen killing following infection. To identify possible age-related alterations in macrophage function, we have assayed the function of peritoneal macrophages from young (3–4 months) and aged (14–15 months) Balb/c mice. In agreement with prior suggestions, we observe age-dependent increases in the extent of recruitment of macrophages into the peritoneum, as well as ex vivo functional changes involving enhanced nitric oxide production under resting conditions that contribute to a reduction in the time needed for full activation of senescent macrophages following exposure to lipopolysaccharides (LPS). Further, we observe enhanced bactericidal activity following Salmonella uptake by macrophages isolated from aged Balb/c mice in comparison with those isolated from young animals. Pathways responsible for observed phenotypic changes were interrogated using tandem mass spectrometry, which identified age-dependent increases in levels of proteins linked to immune cell pathways under basal conditions and following LPS activation. Immune pathways upregulated in macrophages isolated from aged mice include proteins critical to the formation of the immunoproteasome. Detection of these latter proteins is dramatically enhanced following LPS exposure for macrophages isolated from aged animals; in comparison, the identification of immunoproteasome subunits is insensitive to LPS exposure for macrophages isolated from young animals. Consistent with observed global changes in the proteome, quantitative proteomic measurements indicate that there are age-dependent abundance changes involving specific proteins linked to immune cell function under basal conditions. LPS exposure selectively increases the levels of many proteins involved in immune cell function in aged Balb/c mice

  8. Aging enhances the production of reactive oxygen species and bactericidal activity in peritoneal macrophages by upregulating classical activation pathways.

    PubMed

    Smallwood, Heather S; López-Ferrer, Daniel; Squier, Thomas C

    2011-11-15

    Maintenance of macrophages in their basal state and their rapid activation in response to pathogen detection are central to the innate immune system, acting to limit nonspecific oxidative damage and promote pathogen killing following infection. To identify possible age-related alterations in macrophage function, we have assayed the function of peritoneal macrophages from young (3-4 months) and aged (14-15 months) Balb/c mice. In agreement with prior suggestions, we observe age-dependent increases in the extent of recruitment of macrophages into the peritoneum, as well as ex vivo functional changes involving enhanced nitric oxide production under resting conditions that contribute to a reduction in the time needed for full activation of senescent macrophages following exposure to lipopolysaccharides (LPS). Further, we observe enhanced bactericidal activity following Salmonella uptake by macrophages isolated from aged Balb/c mice in comparison with those isolated from young animals. Pathways responsible for observed phenotypic changes were interrogated using tandem mass spectrometry, which identified age-dependent increases in levels of proteins linked to immune cell pathways under basal conditions and following LPS activation. Immune pathways upregulated in macrophages isolated from aged mice include proteins critical to the formation of the immunoproteasome. Detection of these latter proteins is dramatically enhanced following LPS exposure for macrophages isolated from aged animals; in comparison, the identification of immunoproteasome subunits is insensitive to LPS exposure for macrophages isolated from young animals. Consistent with observed global changes in the proteome, quantitative proteomic measurements indicate that there are age-dependent abundance changes involving specific proteins linked to immune cell function under basal conditions. LPS exposure selectively increases the levels of many proteins involved in immune cell function in aged Balb/c mice

  9. Asbestos-activated peritoneal macrophages release a factors(s) which inhibits lymphocyte mitogenesis

    SciTech Connect

    Donaldson, K.; Davis, J.M.G.; James, K.

    1984-10-01

    Intraperitoneal asbestos injection in mice has previously been reported to elicit an activated macrophage population. In the present study supernatants from such macrophages were tested for their effect on thymocyte mitogenesis in response to concanavalin A; control supernantants were obtained from saline- and latex-elicited macrophages. Supernatants from asbestos-elicited macrophages were significantly inhibitory to thymocyte mitogenesis while saline- and latex-elicited macrophages did not release significant amounts of such activity. Asbestos-activated macrophage supernatants were inhibitory in a dose-dependent way and the activity was not secreted by macrophages from mice which had received asbestos in the long term. The inhibitory activity was partially dialysable. Supernatants prepared by treating macrophages in vitro with a lethal dose of asbestos were not inhibitory suggesting that the inhibitory activity in the supernatants of asbestos-activated macrophages did not leak from dead or dying cells. The asbestos macrophage supernatant was also significantly inhibitory to mature T-cell-enriched spleen cells but had no effect on fibroblasts, suggesting that the inhibitory effect could be lymphoid cell specific.

  10. Subcellular localization of the PGE2 synthesis activity in mouse resident peritoneal macrophages

    PubMed Central

    1984-01-01

    The aim of this work was to establish, on a quantitative basis, the subcellular distribution of the enzyme system that converts arachidonic acid into prostaglandin (PG) E2 in mouse resident peritoneal (MRP) macrophages. Kinetic studies were conducted on cell-free extracts derived from cells cultivated for 1 d, using [1-14C]arachidonic acid as substrate and measuring the label in PGE2 after extraction and thin layer chromatography. The activity was synergistically enhanced by L- adrenaline and reduced glutathione, inhibited by indomethacin, and linearly related to the concentration of the cell-free extract. It was labile at 0 degrees C in the medium used for homogenization and fractionation of the cells (half-life less than 2 h). Addition of catalase (0.15 mg/ml) to the suspension medium increased the initial activity (by congruent to 70%) and the stability (half-life congruent to 6 h) of the enzyme in cytoplasmic extracts. It enabled us to establish the density distribution after isopycnic centrifugation in a linear gradient of sucrose. The sample centrifuged consisted of untreated cytoplasmic extracts, or cytoplasmic extracts treated with digitonin and Na pyrophosphate. Comparison of the centrifugation behavior of PGE2 synthesis activity with that of various enzymes used as reference for the major subcellular entities has revealed that PGE2 synthesis fairly fits the density profile of sulfatase C in each case. The conclusion is that at least the rate-limiting reaction in the conversion of arachidonic acid into PGE2 is catalyzed by an enzyme associated with the endoplasmic reticulum. PMID:6420497

  11. Hepatic cells' mitotic and peritoneal macrophage phagocytic activities during Trypanosoma musculi infection in zinc-deficient mice.

    PubMed Central

    Humphrey, P. A.; Ashraf, M.; Lee, C. M.

    1997-01-01

    The effects of zinc deficiency on hepatic cell mitotic and peritoneal macrophage phagocytic activities were examined in mice infected with Trypanosoma musculi or immunized with parasitic products. On a full-complement or pair-fed diet, infected and homogenate-inoculated mice showed mitotic activity gains of 7.9% to 80.3% and 6.5% to 99.0%, respectively. Infected and homogenate-inoculated mice on a zinc-deficient diet showed 21.8% to 95.7% and 17.2% to 65.2%, respectively, more dividing liver cells compared with controls. In comparison to controls, macrophages isolated from infected and homogenate-immunized mice on full-complement or pair-fed diets had phagocytized 13.4% to 31.4% more latex particles from day 50 to 80. In the zinc-deficient group, macrophages isolated from infected mice had significant numbers of phagocytized latex particles (1.8% to 38.5%) from day 20 to day 80 compared with controls. The homogenate-immunized mice also had increased numbers (18.6 to 30.8%) of phagocytized latex particles. PMID:9145631

  12. Escherichia coli maltose-binding protein activates mouse peritoneal macrophages and induces M1 polarization via TLR2/4 in vivo and in vitro.

    PubMed

    Ni, Weihua; Zhang, Qingyong; Liu, Guomu; Wang, Fang; Yuan, Hongyan; Guo, Yingying; Zhang, Xu; Xie, Fei; Li, Qiongshu; Tai, Guixiang

    2014-07-01

    Maltose-binding protein (MBP) is a component of the maltose transport system of Escherichia coli. Our previous study found that MBP combined with Bacillus Calmette-Guerin (BCG) increases the percentage of activated macrophages in the spleen and the pinocytic activity of peritoneal macrophages in vivo. However, the effect of MBP alone on macrophages remains unclear. In the present study, the results showed that MBP enhanced LPS-stimulated macrophage activity in vivo. Subsequently, we investigated the regulatory effect of MBP on mouse peritoneal macrophages in vitro and the possible underlying mechanism. The results showed that MBP directly promoted macrophage phagocytic activity and increased the production of NO, IL-1β and IL-6. Notably, macrophage phenotypic analysis showed that MBP significantly increased iNOS, IL-12p70 and CD16/32. In contrast, MBP decreased the secretion of IL-10 and slightly decreased Arg-1 mRNA and CD206 protein expression. These results suggested that MBP activated macrophages and polarized them into M1 macrophages. Further study found that MBP directly bound to macrophages and upregulated TLR2 mRNA expression. This process was accompanied by a clear increase in MyD88 expression and phosphorylation of p38 MAPK and IκB-α, but these effects were largely abrogated by pretreatment with anti-TLR2 or anti-TLR4 antibodies. The effects of MBP on macrophage NO production were also partially inhibited by anti-TLR2 and/or anti-TLR4 antibodies. Furthermore, the effect of MBP on IL-12 and IL-10 secretion was largely influenced by the NF-κB inhibitor PDTC and the p38 MAPK inhibitor SB203580. These results suggest that MBP directly activates macrophages and induces M1 polarization through a process that may involve TLR2 and TLR4.

  13. Relationship between membrane potential changes and superoxide-releasing capacity in resident and activated mouse peritoneal macrophages

    SciTech Connect

    Kitagawa, S.; Johnston, R.B. Jr.

    1985-11-01

    To understand better the molecular basis for the enhanced respiratory burst of activated macrophages (M phi), the relationship between the stimulus-induced changes in membrane potential and release of superoxide anion (O/sub 2//sup -/) in mouse peritoneal M phi was investigated. Resident M phi and M phi elicited by injection of lipopolysaccharide (LPS-M phi) or obtained from animals infected with bacille Calmette-Guerin (BCG-M phi) were used. LPS-M phi and BCG-M phi showed more pronounced changes in membrane potential (depolarization) and greater release of O/sub 2//sup -/ on contact with phorbol myristate acetate (PMA) than did resident macrophages. The lag time between addition of stimulus and onset of release of O/sub 2//sup -/ was reduced in activated compared with resident cells. Membrane potential changes began 60 to 90 sec before release of O/sub 2//sup -/ could be detected in each cell type. The dose-response curves for triggering of membrane potential changes and O/sub 2//sup -/ release by PMA were identical. The magnitude of membrane potential changes and of O/sub 2//sup -/ release in LPS-M phi and BCG-M phi declined progressively during in vitro culture, and values on day 3 approached those in resident macrophages (deactivation). Extracellular glucose was required for effective stimulated change in membrane potential and O/sub 2//sup -/ release. These findings indicate that membrane potential changes are closely associated with O/sub 2//sup -/-releasing capacity in macrophages, and that the systems that mediate membrane potential changes and production of O/sub 2//sup -/ develop or decline concomitantly during activation or deactivation of the cells.

  14. Effect of the native polysaccharide of cashew-nut tree gum exudate on murine peritoneal macrophage modulatory activities.

    PubMed

    Yamassaki, F T; Lenzi, R M; Campestrini, L H; Bovo, F; Seyfried, M; Soldera-Silva, A; Stevan-Hancke, F R; Zawadzki-Baggio, S F; Pettolino, F A; Bacic, A; Maurer, J B B

    2015-07-10

    The native polysaccharide of cashew-nut tree gum exudate (CNTG) and its arabinogalactan-protein component (CNTG-AGP) were tested by using immuno-stimulant and anti-inflammatory in vitro assays of murine peritoneal macrophage activities. In the assay for immuno-stimulant activity (without previous treatment with lipopolysaccharide; LPS), CNTG increased the production of interleukin (IL)-10 and both CNTG and CNTG-AGP decreased the concentrations of IL6. When the macrophages were incubated in the presence of LPS and CNTG a decrease in the levels of nitric oxide (NO(·)) and IFN-γ was observed. The results could explain the popular use of CNTG as an anti-inflammatory. In addition, CNTG is the main component of the cashew-nut tree gum exudate, which has been considered a versatile polymer with potential pharmaceutical and food industry applications. These data may contribute to the study of the immunomodulation activity of plant polysaccharides, as well as encourage future experiments in the field of cashew-nut tree gum exudate applications.

  15. Interleukin-12 synthesis is a required step in trehalose dimycolate-induced activation of mouse peritoneal macrophages.

    PubMed Central

    Oswald, I P; Dozois, C M; Petit, J F; Lemaire, G

    1997-01-01

    Trehalose dimycolate (TDM), a glycolipid present in the cell wall of Mycobacterium spp., is a powerful immunostimulant. TDM primes murine macrophages (Mphi) to produce nitric oxide (NO) and to develop antitumoral activity upon activation with low doses of lipopolysaccharide (LPS). In this study, we investigated the ability of TDM to induce interleukin 12 (IL-12) and the role of this cytokine in TDM-induced activation of murine Mphi. RNA isolated from peritoneal exudate cells (PEC) collected at different times after TDM injection was used to determine IL-12 (p35 and p40 subunits) and gamma interferon (IFN-gamma) mRNA levels by semiquantitative reverse transcriptase-PCR. Constitutive expression of IL-12p35 was observed in PEC from untreated as well as from TDM-injected mice. In contrast, expression of the IL-12p40 subunit was almost undetectable in control PEC but was dramatically upregulated in PEC from TDM-injected mice. IL-12p40 expression peaked at 8 h and subsided to baseline levels at 39 h postinjection. TDM was also able to induce IFN-gamma expression; however, kinetics of induction of IFN-gamma was different from that of IL-12p40. Maximal levels of IFN-gamma mRNA were reached by 24 h and did not return to baseline by 4 days. In addition, pretreatment of mice with neutralizing monoclonal antibodies directed against IL-12 (C15.6.7 and C15.1.2) blocked IFN-gamma mRNA induction in PEC from TDM-treated mice. We further determined if the induction of IL-12 and/or IFN-gamma contributes to the in vivo priming effect of TDM on peritoneal Mphi. TDM-injected mice were treated in vivo with anti-IL-12 or anti-IFN-gamma (XMG.1.6) monoclonal antibodies. TDM-primed Mphi were then activated in vitro with LPS and tested for their ability to produce NO and to develop cytostatic activity toward cocultivated L1210 tumor cells. Priming of Mphi by TDM was completely blocked by in vivo neutralization of either IL-12 or IFN-gamma as demonstrated by an absence of tumoricidal activity

  16. Immunological impact of magnetic nanoparticles (Ferucarbotran) on murine peritoneal macrophages

    NASA Astrophysics Data System (ADS)

    Yeh, Chen-Hao; Hsiao, Jong-Kai; Wang, Jaw-Lin; Sheu, Fuu

    2010-01-01

    Ferucarbotran, a clinically used superparamagnetic iron oxide, is widely developed as a magnetic resonance imaging (MRI) contrast agent and has the potential to improve the monitoring of macrophage recirculation in vivo. However, the biological effect of Ferucarbotran or magnetic nanoparticles (MNPs) on macrophage is not clearly understood yet. This study is aimed to examine the immunological impact of Ferucarbotran toward murine peritoneal macrophages. Cells treated with Ferucarbotran demonstrated a dose-responsive increase of granularity in the cytoplasm. After 24 h of incubation, viability and cytotoxicity in macrophages treated with 200 μg Fe/mL of Ferucarbotran were not affected. Macrophages loaded with Ferucarbotran above 100 μg Fe/mL showed a significant ( p < 0.01) increase in cytokine (TNF-α, IL-1β, IL-6) secretion and mRNA expression, followed by nitric oxide (NO) secretion and iNOS mRNA expression. Chemotactic responses of Ferucarbotran-preloaded macrophages toward CX3CL1 were significantly ( p < 0.05) lower than those of untreated macrophages. Taking together, Ferucarbotran at high dose (100 μg Fe/mL) could induce murine peritoneal macrophages activation in pro-inflammatory cytokine secretion and NO production.

  17. Evaluation of the Leishmanicidal Activity of Rutaceae and Lauraceae Ethanol Extracts on Golden Syrian Hamster (Mesocricetus auratus) Peritoneal Macrophages.

    PubMed

    Chávez Enciso, N A; Coy-Barrera, E D; Patiño, O J; Cuca, L E; Delgado, Gabriela

    2014-05-01

    Traditional medicine has provided a number of therapeutic solutions for the control of infectious agents, cancers, and other diseases. After screening a wide variety of Colombian plant extracts, we have identified promising antileishmanial activity in ethanol extracts from Ocotea macrophylla (Lauraceae) and Zanthoxyllum monophyllum (Rutaceae). In this study, we evaluated the in vitro activity of two ethanol extracts, one from Ocotea macrophylla and the other from Zanthoxyllum monophyllum and one alkaloid fraction of ethanol extract of Zanthoxyllum monophyllum, on peritoneal macrophages isolated from golden Syrian hamsters (Mesocricetus auratus) infected with Leishmania panamensis and Leishmania major promastigotes. All of the extracts studied displayed promising (≥2) selectivity indices (S/I), the most significant of which were for ethanol extract of Zanthoxyllum monophyllum against Leishmania panamensis (S/I=12) and alkaloid fraction of ethanol extract of Zanthoxyllum monophyllum against Leishmania major (S/I=11). These results support the use of ethanol extracts and alkaloid fractions isolated from Ocotea macrophylla and Zanthoxyllum monophyllum, respectively; as therapeutic options for cutaneous leishmaniasis.

  18. Evaluation of the Leishmanicidal Activity of Rutaceae and Lauraceae Ethanol Extracts on Golden Syrian Hamster (Mesocricetus auratus) Peritoneal Macrophages

    PubMed Central

    Chávez Enciso, N. A.; Coy-barrera, E. D.; Patiño, O. J.; Cuca, L. E.; Delgado, Gabriela

    2014-01-01

    Traditional medicine has provided a number of therapeutic solutions for the control of infectious agents, cancers, and other diseases. After screening a wide variety of Colombian plant extracts, we have identified promising antileishmanial activity in ethanol extracts from Ocotea macrophylla (Lauraceae) and Zanthoxyllum monophyllum (Rutaceae). In this study, we evaluated the in vitro activity of two ethanol extracts, one from Ocotea macrophylla and the other from Zanthoxyllum monophyllum and one alkaloid fraction of ethanol extract of Zanthoxyllum monophyllum, on peritoneal macrophages isolated from golden Syrian hamsters (Mesocricetus auratus) infected with Leishmania panamensis and Leishmania major promastigotes. All of the extracts studied displayed promising (≥2) selectivity indices (S/I), the most significant of which were for ethanol extract of Zanthoxyllum monophyllum against Leishmania panamensis (S/I=12) and alkaloid fraction of ethanol extract of Zanthoxyllum monophyllum against Leishmania major (S/I=11). These results support the use of ethanol extracts and alkaloid fractions isolated from Ocotea macrophylla and Zanthoxyllum monophyllum, respectively; as therapeutic options for cutaneous leishmaniasis. PMID:25035529

  19. CRIg-expressing peritoneal macrophages are associated with disease severity in patients with cirrhosis and ascites

    PubMed Central

    Irvine, Katharine M.; Banh, Xuan; Gadd, Victoria L.; Wojcik, Kyle K.; Ariffin, Juliana K.; Jose, Sara; Lukowski, Samuel; Baillie, Gregory J.; Sweet, Matthew J.; Powell, Elizabeth E.

    2016-01-01

    Infections are an important cause of morbidity and mortality in patients with decompensated cirrhosis and ascites. Hypothesizing that innate immune dysfunction contributes to susceptibility to infection, we assessed ascitic fluid macrophage phenotype and function. The expression of complement receptor of the immunoglobulin superfamily (CRIg) and CCR2 defined two phenotypically and functionally distinct peritoneal macrophage subpopulations. The proportion of CRIghi macrophages differed between patients and in the same patient over time, and a high proportion of CRIghi macrophages was associated with reduced disease severity (model for end-stage liver disease) score. As compared with CRIglo macrophages, CRIghi macrophages were highly phagocytic and displayed enhanced antimicrobial effector activity. Transcriptional profiling by RNA sequencing and comparison with human macrophage and murine peritoneal macrophage expression signatures highlighted similarities among CRIghi cells, human macrophages, and mouse F4/80hi resident peritoneal macrophages and among CRIglo macrophages, human monocytes, and mouse F4/80lo monocyte-derived peritoneal macrophages. These data suggest that CRIghi and CRIglo macrophages may represent a tissue-resident population and a monocyte-derived population, respectively. In conclusion, ascites fluid macrophage subset distribution and phagocytic capacity is highly variable among patients with chronic liver disease. Regulating the numbers and/or functions of these macrophage populations could provide therapeutic opportunities in cirrhotic patients. PMID:27699269

  20. Lipopolysaccharide (LPS) alters phosphatidylcholine metabolism in elicited peritoneal macrophages

    SciTech Connect

    Grove, R.I.; Allegretto, N.J.; Kiener, P.A.; Warr, G.A. )

    1990-07-01

    We investigated the effects of LPS on mouse peritoneal macrophage phospholipids using radiolabeled precursors. LPS (200 ng/ml) stimulated incorporation of ({sup 32}P) into all classes of phospholipids within 0.5 hr, and after 2 hr the increase was 60% greater than controls. Separation of the phospholipid classes by thin-layer chromatography revealed a selective increase in incorporation of label into phosphatidylcholine (PC) (90% increase compared to approximately 50% in the other phospholipids). In macrophages labeled with ({sup 3}H)-choline, LPS stimulated both the incorporation of label into PC and the release of incorporated label into the medium. The time dependencies of stimulated ({sup 3}H) release and ({sup 32}P) incorporation were similar. These data are consistent with the hypothesis that LPS activates macrophages via a PC-specific phospholipase-dependent mechanism.

  1. Large-conductance channel formation mediated by P2X7 receptor activation is regulated through distinct intracellular signaling pathways in peritoneal macrophages and 2BH4 cells.

    PubMed

    Faria, R X; Cascabulho, C M; Reis, R A M; Alves, Luiz Anastácio

    2010-07-01

    The P2X(7) receptor (P2X7R) is a ligand-gated ATP receptor that acts as a low- and large-conductance channel (pore) and is known to be coupled to several downstream effectors. Recently, we demonstrated that the formation of a large-conductance channel associated with the P2X(7) receptor is induced by increasing the intracellular Ca(2+) concentration (Faria et al., Am J Physiol Cell Physiol 297:C28-C42, 2005). Here, we investigated the intracellular signaling pathways associated with P2X(7) large-conductance channel formation using the patch clamp technique in conjunction with fluorescent imaging and flow cytometry assays in 2BH4 cells and peritoneal macrophages. Different antagonists were applied to investigate the following pathways: Ca(2+)-calmodulin, phospholipase A, phospholipase D, phospholipase C, protein kinase C (PKC), mitogen-activated protein kinase (MAPK), MAPK/extracellular signal-regulated kinase, phosphoinositide 3-kinase (PI3K), and cytoskeletal proteins. Macroscopic ionic currents induced by 1 mM ATP were reduced by 85% in the presence of PKC antagonists. The addition of antagonists for MAPK, PI3K, and the cytoskeleton (actin, intermediary filament, and microtubule) blocked 92%, 83%, and 95% of the ionic currents induced by 1 mM ATP, respectively. Our results show that PKC, MAPK, PI3K, and cytoskeletal components are involved in P2X(7) receptor large-channel formation in 2BH4 cells and peritoneal macrophages.

  2. Immunoregulation by macrophages II. Separation of mouse peritoneal macrophages having tumoricidal and bactericidal activities and those secreting PGE and interleukin I

    SciTech Connect

    Hopper, K.E.; Cahill, J.M.

    1983-06-01

    Macrophage subpopulations having bactericidal or tumoricidal activities and secreting interleukin I (IL1) or prostaglandin E (PGE) were identified through primary or secondary infection with Salmonella enteritidis and separated by sedimentation velocity. Bactericidal activity was measured by (3H)-thymidine release from Listeria monocytogenes and tumoricidal activity by 51Cr-release from C-4 fibrosarcoma or P815 mastocytoma cells. Macrophages with bactericidal activity were distinguished from those with tumoricidal activity a) during secondary infection when cytolytic activity occurred only at days 1-4 post injection and bactericidal activity remained high throughout and b) after sedimentation velocity separation. Cytolysis was consistently greatest among adherent cells of low sedimentation velocity, whereas cells with bactericidal activity increased in size during the infection. Tumour cytostasis (inhibition and promotion of (3H)-thymidine uptake) differed from cytolysis in that the former was more prolonged during infection and was also detected among large cells. Secretion of immunoregulatory molecules PGE and IL1 occurred maximally among different macrophage subpopulations separated by sedimentation velocity and depending on the type of stimulus used in vitro. There was an inverse correlation between IL1 production and PGE production after stimulation with C3-zymosan or lipopolysaccharide (LPS). The development of immunity during infection may therefore be dependent upon the relative proportions of effector and regulatory macrophage subpopulations and the selective effects of environmental stimuli on these functions.

  3. Aging impairs peritoneal but not bone marrow-derived macrophage phagocytosis.

    PubMed

    Linehan, Eimear; Dombrowski, Yvonne; Snoddy, Rachel; Fallon, Padraic G; Kissenpfennig, Adrien; Fitzgerald, Denise C

    2014-08-01

    Aging results in deterioration of the immune system, which is associated with increased susceptibility to infection and impaired wound healing in the elderly. Phagocytosis is an essential process in both wound healing and immune defence. As such, age-related impairments in phagocytosis impact on the health of the elderly population. Phagocytic efficiency in peritoneal macrophages, bone marrow-derived macrophages and bone marrow monocytes from young and old mice was investigated. Aging significantly impaired phagocytosis by peritoneal macrophages, both in vitro and in vivo. However, bone marrow-derived macrophages and bone marrow monocytes did not exhibit age-related impairments in phagocytosis, suggesting no intrinsic defect in these cells. We sought to investigate underlying mechanisms in age-related impairments in phagocytosis by peritoneal macrophages. We hypothesized that microenvironmental factors in the peritoneum of old mice impaired macrophage phagocytosis. Indeed, macrophages from young mice injected into the peritoneum of old mice exhibited impaired phagocytosis. Proportions of peritoneal immune cells were characterized, and striking increases in numbers of T cells, B1 and B2 cells were observed in the peritoneum of old mice compared with young mice. In addition, B cell-derived IL-10 was increased in resting and LPS-activated peritoneal cell cultures from old mice. These data demonstrate that aging impairs phagocytosis by tissue-resident peritoneal macrophages, but not by bone marrow-derived macrophages/monocytes, and suggest that age-related defects in macrophage phagocytosis may be due to extrinsic factors in the tissue microenvironment. As such, defects may be reversible and macrophages could be targeted therapeutically in order to boost immune function in the elderly.

  4. Immunostimulatory effect of spinach aqueous extract on mouse macrophage-like J774.1 cells and mouse primary peritoneal macrophages.

    PubMed

    Ishida, Momoko; Ose, Saya; Nishi, Kosuke; Sugahara, Takuya

    2016-07-01

    We herein report the immunostimulatory effect of spinach aqueous extract (SAE) on mouse macrophage-like J774.1 cells and mouse primary peritoneal macrophages. SAE significantly enhanced the production of interleukin (IL)-6 and tumor necrosis factor-α by both J774.1 cells and peritoneal macrophages by enhancing the expression levels of these cytokine genes. In addition, the phagocytosis activity of J774.1 cells was facilitated by SAE. Immunoblot analysis revealed that SAE activates mitogen-activated protein kinase and nuclear factor-κB cascades. It was found that SAE activates macrophages through not only TLR4, but also other receptors. The production of IL-6 was significantly enhanced by peritoneal macrophages from SAE-administered BALB/c mice, suggesting that SAE has a potential to stimulate macrophage activity in vivo. Taken together, these data indicate that SAE would be a beneficial functional food with immunostimulatory effects on macrophages.

  5. The equine alveolar macrophage: functional and phenotypic comparisons with peritoneal macrophages.

    PubMed

    Karagianni, Anna E; Kapetanovic, Ronan; McGorum, Bruce C; Hume, David A; Pirie, Scott R

    2013-10-01

    Alveolar macrophages (AMs) constitute the first line of defence in the lung of all species, playing a crucial role in the regulation of immune responses to inhaled pathogens. A detailed understanding of the function and phenotype of AMs is a necessary pre-requisite to both elucidating their role in preventing opportunistic bacterial colonisation of the lower respiratory tract and developing appropriate preventative strategies. The purpose of the study was to characterise this important innate immune cell at the tissue level by making functional and phenotypic comparisons with peritoneal macrophages (PMs). We hypothesised that the tissue of origin determines a unique phenotype of AMs, which may constitute an appropriate therapeutic target for certain equine respiratory diseases. Macrophages isolated from the lung and the peritoneal cavity of 9 horses were stimulated with various toll like receptor (TLR) ligands and the production of nitrite, tumour necrosis factor alpha (TNFα), interleukin (IL) 10 and indoleamine 2,3-dioxygenase (IDO) were measured by the Griess reaction and enzyme linked immunosorbent assay (ELISA) and/or quantitative polymerase chain reaction, respectively. Cells were also compared on the basis of phagocytic-capacity and the expression of several cell surface markers. AMs, but not PMs, demonstrated increased TNFα release following stimulation with LPS, polyinosinic polycytidylic acid (Poly IC) and heat-killed Salmonella typhinurium and increased TNFα and IDO mRNA expression when stimulated with LPS. AMs showed high expression of the specific macrophage markers cluster of differentiation (CD) 14, CD163 and TLR4, whereas PMs showed high expression of TLR4 only. AMs, but not PMs, demonstrated efficient phagocytic activity. Our results demonstrate that AMs are more active than PMs when stimulated with various pro-inflammatory ligands, thus supporting the importance of the local microenvironment in the activation status of the macrophage. This

  6. Growth of Mycobacterium lepraemurium in nonstimulated and stimulated mouse peritoneal-derived and bone marrrow-derived macrophages in vitro.

    PubMed Central

    Alexander, J; Smith, C C

    1978-01-01

    Mycobacterium lepraemurium cells were found to multiply in normal mouse peritoneal-derived and bone marrow-derived macrophages in vitro. Whereas activated peritoneal-derived macrophages demonstrated marked bacteriostasis for M. lepraemurium, significant bactericidal activity was exhibited by activated bone marrow-derived macrophages. However, only a small proportion of the bacterial were killed by activated bone marrow-derived macrophages with subsequent and enhanced bacteria growth. It is suggested that a rapid turnover of monocytes in active lesions is required to control mycobacterial infections in vivo. These results would suggest that careful consideration be given to the choice of the host cell in studies involving obligate intracellular parasites. PMID:365762

  7. Single-cell analysis reveals new subset markers of murine peritoneal macrophages and highlights macrophage dynamics upon Staphylococcus aureus peritonitis.

    PubMed

    Accarias, Solène; Genthon, Clémence; Rengel, David; Boullier, Séverine; Foucras, Gilles; Tabouret, Guillaume

    2016-07-01

    Resident macrophages play a central role in maintaining tissue homeostasis and immune surveillance. Here, we used single cell-based qPCR coupled with flow cytometry analysis to further define the phenotypes of large and small resident peritoneal macrophages (LPMs and SPMs, respectively) in mice. We demonstrated that the expression of Cxcl13, IfngR1, Fizz-1 and Mrc-1 clearly distinguished between LPMs and SPMs subsets. Using these markers, the dynamics of peritoneal macrophages in a Staphylococcus aureus-induced peritonitis model were analyzed. We found that S. aureus infection triggers a massive macrophage disappearance reaction in both subsets. Thereafter, inflammatory monocytes rapidly infiltrated the cavity and differentiated to replenish the SPMs. Although phenotypically indistinguishable from resident SPMs by flow cytometry, newly recruited SPMs had a different pattern of gene expression dominated by M2 markers combined with M1 associated features (inos expression). Interestingly, S. aureus elicited SPMs showed a robust expression of Cxcl13, suggesting that these cells may endorse the role of depleted LPMs and contribute to restoring peritoneal homeostasis. These data provide information on both resident and recruited macrophages dynamics upon S. aureus infection and demonstrate that single-cell phenotyping is a promising and highly valuable approach to unraveling macrophage diversity and plasticity.

  8. Antigen presentation by peritoneal macrophages from young adult and old mice

    SciTech Connect

    Perkins, E.H.; Massucci, J.M.; Glover, P.L.

    1982-01-01

    Macrophages perform vital inductive and regulatory functions in immune processes and host defense mechanisms. However, macrophage function during senescence has not been extensively studied. Although antibody response is dramatically reduced in old animals, antigen presentation has never been directly assessed. Therefore, the antigen-presenting capabilities of purified peritoneal macrophages from young adult and old mice were studied by quantitatively measuring their ability to induce antigen specific proliferation of lymph node T lymphocytes. Increasing numbers (10/sup 2/ to 10/sup 5/) of macrophages from nonimmunized young adult (3 to 6 months) or aged (27 to 36 months) animals were cultured in the presence of antigen with a constant number (2 x 10/sup 5/) of column-separated popliteal lymph node cells from young adult mice. The latter had been immunized with the dinitrophenyl conjugate of bovine ..gamma..-globulin in complete Freund's adjuvant by footpad injection. Macrophages from old animals were equal to macrophages from young adult in stimulating T-lymphocyte proliferation, and the kinetics of incorporation was identical with increasing numbers of macrophages from either young adult or old animals. However, greater numbers of resident or induced peritoneal macrophages were always harvested from old animals. Differences in macrophage activity as assessed by different functional parameters may be reconciled by implicating subpopulations of macrophages that perform separate functions, e.g. Ia-positive antigen presenter and Ia-negative scavenger macrophages.

  9. Vascular endothelial growth factor is produced by peritoneal fluid macrophages in endometriosis and is regulated by ovarian steroids.

    PubMed Central

    McLaren, J; Prentice, A; Charnock-Jones, D S; Millican, S A; Müller, K H; Sharkey, A M; Smith, S K

    1996-01-01

    Angiogenesis is important in the pathophysiology of endometriosis, a condition characterized by implantation of ectopic endometrium in the peritoneal cavity. Vascular endothelial growth factor (VEGF) is a potent angiogenic factor involved in physiological and pathological angiogenesis, and elevated levels of VEGF are found in peritoneal fluid of patients with endometriosis. Our aim was to investigate the site of expression and regulation of VEGF in endometriosis. VEGF immunoreactivity was found in tissue macrophages present in ectopic endometrium and in activated peritoneal fluid macrophages. Macrophage activation was highest in women with endometriosis, and media conditioned by peritoneal fluid macrophages from these women caused a VEGF-dependent increase in endothelial cell proliferation above that seen from normal women. Peritoneal fluid macrophages secreted VEGF in response to ovarian steroids, and this secretion was enhanced after activation with lipopolysaccharide. Peritoneal fluid macrophages expressed receptors for steroid hormones. VEGF receptors flt and KDR (kinase domain receptor) were also detected, suggesting autocrine regulation. During the menstrual cycle, expression of flt was constant but that of KDR was increased in the luteal phase, at which time the cells migrated in response to VEGF. KDR expression and the migratory response were significantly higher in patients with endometriosis. This study demonstrates that activated macrophages are a major source of VEGF in endometriosis and that this expression is regulated directly by ovarian steroids. PMID:8755660

  10. Survival and replication of Escherichia coli O157:H7 inside the mice peritoneal macrophages

    PubMed Central

    Al-Mariri, Ayman

    2008-01-01

    The replication of Escherichia coli O157:H7 on the resident peritoneal macrophages of four mice strains (BALB/c, CD1, C57BL, and Swiss) has been investigated. Macrophagial bactericidal killing activity was estimated via studying their ability to internalize (gentamicin-protected) E. coli during 2, 4, 24, and 48 h assays. Host genetic background has been found to show no significant effect on the ability of resident peritoneal macrophages to kill E. coli O157:H7. PMID:24031167

  11. Nitric oxide is overproduced by peritoneal macrophages in rat taurocholate pancreatitis: the mechanism of inducible nitric oxide synthase expression.

    PubMed

    Satoh, A; Shimosegawa, T; Kimura, K; Moriizumi, S; Masamune, A; Koizumi, M; Toyota, T

    1998-11-01

    To investigate the pathobiology of severe acute pancreatitis, we studied the expression of inducible nitric oxide synthase (iNOS) in peritoneal macrophages of experimental pancreatitis. Taurocholate (TCA) pancreatitis and cerulein (CE) pancreatitis were used as models of lethal and self-limited pancreatitis, respectively, and the mechanism of iNOS expression in peritoneal macrophages was studied. Serum nitrate and nitrite (NOx) concentrations increased during the course of TCA pancreatitis, and iNOS-immunoreactivity was detected in the peritoneal macrophages 12 h after the induction of TCA pancreatitis, but these phenomena were not observed in CE pancreatitis. Despite the difference in the iNOS expression, the iNOS messenger RNA (mRNA) and the activation of nuclear factor-kappa B (NF-kappa B) were detected in the peritoneal macrophages of both pancreatitis models. The supernatant of TCA pancreatitis ascites could induce iNOS in the peritoneal macrophages of normal rats in vitro, but the peritoneal lavage fluid of CE pancreatitis rats could not. The results indicated that there may be qualitative or quantitative differences in the macrophage activation between the two types of experimental pancreatitis and suggested that the ascites of rats with lethal acute pancreatitis contains some soluble factors that activate the macrophage/monocyte system and cause an overproduction of NO by the iNOS expression.

  12. In vitro Staphylococcus aureus-induced oxidative stress in mice murine peritoneal macrophages: a duration-dependent approach

    PubMed Central

    Chakraborty, Subhankari Prasad; Roy, Somenath

    2014-01-01

    Objective To evaluate the free radical generation and status of the antioxidant enzymes in murine peritoneal macrophage during in vitro vancomycin sensitive Staphylococcus aureus (VSSA) treatment with different time interval. Methods Peritoneal macrophages were treated with 5×106 CFU/mL VSSA cell suspension in vitro for different time interval (1, 2, 3, 6, 12, and 24 h) and superoxide anion generation, NADPH oxidase activity, myeloperoxidase activity, nitric oxide generation, antioxidant enzyme status and components of glutathione cycle were analyzed. Results Superoxide anion generation, NADPH oxidase activity, myeloperoxidase activity and nitric oxide generation got peak at 3 h, indicating maximum free radical generation through activation of NADPH oxidase in murine peritoneal macrophages during VSSA infection. Reduced glutathione level, glutathione peroxidase, glutathione reductase, and glutathione-s-transferase activity were decreased significantly (P<0.05) with increasing time of VSSA infection. But the oxidized glutathione level was time dependently increased significantly (P<0.05) in murine peritoneal macrophages. All the changes in peritoneal macrophages after 3 h in vitro VSSA treatment had no significant difference. Conclusions From this study, it may be summarized that in vitro VSSA infection not only generates excess free radical but also affects the antioxidant status and glutathione cycle in murine peritoneal macrophages. PMID:25183101

  13. Protective effects of Mangifera indica L. extract, mangiferin and selected antioxidants against TPA-induced biomolecules oxidation and peritoneal macrophage activation in mice.

    PubMed

    Sánchez, G M; Re, L; Giuliani, A; Núñez-Sellés, A J; Davison, G P; León-Fernández, O S

    2000-12-01

    We compared the protective abilities of Mangifera indica L. stem bark extract (Vimang) 50-250 mgkg(-1), mangiferin 50 mgkg(-1), vitamin C 100 mgkg(-1), vitamin E 100 mgkg(-1)and beta -carotene 50 mgkg(-1)against the 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced oxidative damage in serum, liver, brain as well as in the hyper-production of reactive oxygen species (ROS) by peritoneal macrophages. The treatment of mice with Vimang, vitamin E and mangiferin reduced the TPA-induced production of ROS by the peritoneal macrophages by 70, 17 and 44%, respectively. Similarly, the H(2)O(2)levels were reduced by 55-73, 37 and 40%, respectively, when compared to the control group. The TPA-induced sulfhydryl group loss in liver homogenates was attenuated by all the tested antioxidants. Vimang, mangiferin, vitamin C plus E and beta -carotene decreased TPA-induced DNA fragmentation by 46-52, 35, 42 and 17%, respectively, in hepatic tissues, and by 29-34, 22, 41 and 17%, in brain tissues. Similar results were observed in respect to lipid peroxidation in serum, in hepatic mitochondria and microsomes, and in brain homogenate supernatants. Vimang exhibited a dose-dependent inhibition of TPA-induced biomolecule oxidation and of H(2)O(2)production by peritoneal macrophages. Even if Vimang, as well as other antioxidants, provided significant protection against TPA-induced oxidative damage, the former lead to better protection when compared with the other antioxidants at the used doses. Furthermore, the results indicated that Vimang is bioavailable for some vital target organs, including liver and brain tissues, peritoneal exudate cells and serum. Therefore, we conclude that Vimang could be useful to prevent the production of ROS and the oxidative tissue damages in vivo.

  14. Protective effect of natural flavonoids on rat peritoneal macrophages injury caused by asbestos fibers.

    PubMed

    Kostyuk, V A; Potapovich, A I; Speransky, S D; Maslova, G T

    1996-01-01

    Exposure of macrophages to asbestos fibers resulted in enhancement of the production of oxygen radicals, determined by a lucigenin enhanced chemiluminescence (LEC) assay, a formation of thiobarbituric acid reactive substances (TBARS), a LDH release into the incubation mixture, and a rapid lysis of the cells. Rutin (Rut) and quercetin (Qr) were effective in inhibiting LEC, TBARS formation, and reducing peritoneal macrophages injury caused by asbestos. The concentrations pre-treatment of antioxidants that were required to prevent the injury of peritoneal macrophages caused by asbestos by 50% (IC50) were 90 microM and 290 microM for Qr and Rut, respectively. Both flavonoids were found to be oxidized during exposure of peritoneal macrophages to asbestos and the oxidation was SOD sensitive. The efficacy of flavonoids as antioxidant agents as well as superoxide ion scavengers was also evaluated using appropriate model systems, and both quercetin and rutin were found to be effective in scavenging O2.-. These findings indicate that flavonoids are able to prevent the respiratory burst in rat peritoneal macrophages exposed to asbestos at the stage of activated oxygen species generation, mainly as superoxide scavengers. On the basis of this study it was concluded that natural flavonoids quercetin and rutin would be promising drug candidates for a prophylactic asbestos-induced disease.

  15. Effects of microwave exposure on the hamster immune system. II. Peritoneal macrophage function

    SciTech Connect

    Rama Rao, G.; Cain, C.A.; Lockwood, J.; Tompkins, W.A.

    1983-01-01

    Acute exposure to hamsters to microwave energy (2.45 GHz; 25 mW/cm2 for 60 min) resulted in activation of peritoneal macrophages that were significantly more viricidal to vaccinia virus as compared to sham-exposed or normal (minimum-handling) controls. Macrophages from microwave-exposed hamsters became activated as early as 6 h after exposure and remained activated for up to 12 days. The activation of macrophages by microwave exposure paralleled the macrophage activation after vaccinia virus immunization. Activated macrophages from vaccinia-immunized hamsters did not differ in their viricidal activity when the hamsters were microwave- or sham-exposed. Exposure for 60 min at 15 mW/cm2 did not activate the macrophages while 40 mW/cm2 exposure was harmful to some hamsters. Average maximum core temperatures in the exposed (25 mW/cm2) and sham groups were 40.5 degrees C (+/- 0.35 SD) and 38.4 degrees C (+/- 0.5 SD), respectively. In vitro heating of macrophages to 40.5 degrees C was not as effective as in vivo microwave exposure in activating macrophages to the viricidal state. Macrophages from normal, sham-exposed, and microwave-exposed hamsters were not morphologically different, and they all phagocytosed India ink particles. Moreover, immune macrophage cytotoxicity for virus-infected or noninfected target cells was not suppressed in the microwave-irradiated group (25 mW/cm2, 1 h) as compared to sham-exposed controls, indicating that peritoneal macrophages were not functionally suppressed or injured by microwave hyperthermia.

  16. Macrophage Biochemistry, Activation and Function

    DTIC Science & Technology

    1981-01-01

    glucoeidase +8 . . Sulfatase c +8 Modified from Morahan, 1980. b(+)Exhibit@ activity; (-) lacks activity; (+) weak or marginal activity. ’References: (1...endoplasmic reticulum enzymes, sulfatase c and alkaline a-glucosidase. Dissociation of the lysosomal enzyme patterns from sulfatase c and alkaline r...1974; Beaufay et al., 1974). Peritoneal macrophages are deficient or contain inauf- • -𔃼 :’- 41 ficient quantities of the classical constituents to be

  17. Elicitation of macrophages from the peritoneal cavity of channel catfish

    USGS Publications Warehouse

    Jenkins, J.A.; Klesius, P.H.

    1998-01-01

    Four chemicals were evaluated for elicitation of macrophages in peritoneal cavities of 250-300g healthy channel catfish Ictalurus punctatus. Cellular exudates were collected at 3, 5, 7, 10, 14, and 20 d following intraperitoneal injections with squalene, Freund's incomplete adjuvant (FIA), goat serum, thioglycollate, or as a control, phosphate-buffered saline. Injection with either squalene or FIA induced significantly greater (P ??? 0.0001) macrophage recruitment than the other chemicals. The effectiveness of squalene and FIA was compared further by macrophage collection daily for 7 d. Squalene and FIA elicited similarly high macrophage responses (P ??? 0.0450), the highest being 3.43 x 106 macrophages/mL (SE, 2.4 x l06) at 99% purity at day 2 and 2.1 X 106 macrophages/mL (SE, 0.7 x 106) at day 14 at 80% purity, respectively. In both experiments, the time after injection was not statistically significant, nor was there an interaction between time and chemicals. The occurrence of cells other than macrophages decreased with time to yield macrophage recoveries of 47-99% for squalene and 30-80% for FIA. Two subsets of macrophages were observed by means of flow cytometry. As demonstrated by chemiluminescence, the squalene-elicited cells produced high-energy oxygen compounds important to the phagocytic process.

  18. Bacteroides fragilis induce necrosis on mice peritoneal macrophages: In vitro and in vivo assays

    SciTech Connect

    Vieira, J.M.B.D.; Seabra, S.H.; Vallim, D.C.; Americo, M.A.; Fracallanza, S.E.L.; Vommaro, R.C.; Domingues, R.M.C.P.

    2009-10-02

    Bacteroides fragilis is an anaerobic bacteria component of human intestinal microbiota and agent of infections. In the host B. fragilis interacts with macrophages, which produces toxic radicals like NO. The interaction of activated mice peritoneal macrophages with four strains of B. fragilis was evaluated on this study. Previously was shown that such strains could cause metabolic and morphologic alterations related to macrophage death. In this work propidium iodide staining showed the strains inducing macrophage necrosis in that the labeling was evident. Besides nitroblue tetrazolium test showed that B. fragilis stimulates macrophage to produce oxygen radicals. In vivo assays performed in BalbC mice have results similar to those for in vitro tests as well as scanning electron microscopy, which showed the same surface pore-like structures observed in vitro before. The results revealed that B. fragilis strains studied lead to macrophage death by a process similar to necrosis.

  19. [Effects of alkaloids from Coptidis Rhizoma on mouse peritoneal macrophages in vitro].

    PubMed

    Zhou, Xia; Peng, Yao-zong; Huang, Tao; Li, Ling; Mou, Shao-xia; Kou, Shu-ming; Li, Xue-gang

    2015-12-01

    This work was mainly studied the effects of the four alkaloids from Coptidis Rhizoma on the mouse peritoneal macrophages in vitro and preliminarily discussed the regulating mechanisms. The effect of alkaloids from Coptidis Rhizoma on the vitality of macrophages was measured by the MTT assay. The effect of alkaloids on the phagocytosis of macrophages was determined by neutral red trial and respiratory burst activity was tested by NBT. The expressions of respiratory-burst-associated genes influenced by alkaloids were detected by qRT-PCR. The conformation change of membrane protein in macrophages by the impact of alkaloids was studied by fluorospectro-photometer. Results showed that the four alkaloids from Coptidis Rhizoma could increase the phagocytosis of macrophages in different level and berberine had the best effect. Berberine, coptisine and palmatine had up-regulation effects on respiratory burst activity of mouse peritoneal macrophages stimulated by PMA and regulatory activity on the mRNA expression of PKC, p40phox or p47phox, whereas the epiberberine had no significant influence on respiratory burst. Moreover, alkaloids from Coptidis Rhizoma could change the conformation of membrane protein and the berberine showed the strongest activity. The results suggested that the four alkaloids from Coptidis Rhizoma might activate macrophages through changing the conformation of membrane protein of macrophages and then enhanced the phagocytosis and respiratory burst activity of macrophages. Furthermore, the regulatory mechanism of alkaloids on the respiratory burst activity of macrophages may be also related to the expression level of PKC, p40phox and p47phox.

  20. Morphological effects of autologous hsp70 on peritoneal macrophages in a murine T cell lymphoma.

    PubMed

    Gautam, P K; Kumar, S; Deepak, P; Acharya, A

    2013-12-01

    Heat shock protein 70 is highly conserved cytosolic protein which have important role in growth, development, and apoptosis. Hsp70 is well-known activator of macrophages and enhances the release of specific and non-specific effector molecules that have major role in tumor destruction and immunopotentiation of host. However, morphological effects of hsp 70 has not been carried out, therefore, morphological effects of hsp 70 on murine peritoneal macrophages were examined by light microscopy and scanning electron microscopy. Thioglycolate-induced peritoneal macrophages were prepared from BALB/c mice and cultured for 24 h in the presence of the hsp70. Tumor-associated macrophages treated with 10 μg/ml were varied in shape, mostly spindle shaped, i.e., stretched bidirectionally; surface ruffles were increased and their lamellipodia was prominent which suggest that hsp 70 treatment not only enhances the functional state of the peritoneal macrophages but also initiate immense morphological changes leading to increased endothelium adherence, increased antigen uptake, and increased migration to the inflammatory site.

  1. A thrombin receptor in resident rat peritoneal macrophages

    SciTech Connect

    Kudahl, K.; Fisker, S.; Sonne, O. )

    1991-03-01

    Resident rat peritoneal macrophages possess 6 x 10(2) high-affinity binding sites per cell for bovine thrombin with a Kd of 11 pM, and 7.5 x 10(4) low-affinity sites with a Kd of 5.8 nM. These binding sites are highly specific for thrombin. Half-maximal binding of {sup 125}I-labeled bovine thrombin is achieved after 1 min at 37{degrees}C, and after 12 min at 4 degrees C. The reversibly bound fraction of the ligand dissociates according to a biexponential time course with the rate constants 0.27 and 0.06 min-1 at 4 degrees C. Part of the tracer remains cell-associated even after prolonged incubation, but all cell-associated radio-activity migrates as intact thrombin upon sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The bound thrombin is minimally endocytosed as judged by the resistance to pH 3 treatment, and the receptor does not mediate a quantitatively important degradation of the ligand. The binding is not dependent on the catalytic site of thrombin, since irreversibly inactivated thrombin also binds to the receptor. {sup 125}I-labeled thrombin covalently cross-linked to its receptor migrates in sodium dodecyl sulfate-polyacrylamide gel electrophoresis with a Mr 160,000, corresponding to an approximate receptor size of Mr 120,000.

  2. Suppression of Mcl-1 induces apoptosis in mouse peritoneal macrophages infected with Mycobacterium tuberculosis.

    PubMed

    Wang, Fei-Yu; Wang, Xin-Min; Wang, Chan; Wang, Xiao-Fang; Zhang, Yu-Qing; Wu, Jiang-Dong; Wu, Fang; Zhang, Wan-Jiang; Zhang, Le

    2016-04-01

    The effect of myeloid cell leukemia-1 (Mcl-1) inhibition on apoptosis of peritoneal macrophages in mice infected with Mycobacterium tuberculosis was investigated and the primary signaling pathway associated with the transcriptional regulation of Mcl-1 was identified. Real-time PCR and western blotting indicated that Mcl-1 transcript and protein expression are upregulated during infection with virulent M. tuberculosis H37Rv and Xinjiang strains but not with attenuated M. tuberculosis strain H37Ra or Bacillus Calmette-Guérin. Mcl-1 transcript and protein expression were downregulated by specific inhibitors of the Janus kinase/signal transducer and activator of transcription (JAK/STAT), mitogen-activated protein kinase (MAPK) and phosphoinositol 3-kinase (PI3K) pathways (AG490, PD98059 and LY294002, respectively). The strongest inhibitor of Mcl-1 expression was PD98059, the MAPK inhibitor. Flow cytometry demonstrated that the rate of apoptosis in peritoneal macrophages is significantly higher in mice infected with M. tuberculosis and the rate of apoptosis is correlated with the virulence of the strain of M. tuberculosis. Apoptosis was found to be upregulated by AG490, PD98059 and LY294002, whereas inhibition of the MAPK pathway sensitized the infected macrophages to apoptosis. Taken together, these results suggest that specific downregulation of Mcl-1 significantly increases apoptosis of peritoneal macrophages and that the MAPK signaling pathway is the primary mediator of Mcl-1 expression.

  3. Esculin exhibited anti-inflammatory activities in vivo and regulated TNF-α and IL-6 production in LPS-stimulated mouse peritoneal macrophages in vitro through MAPK pathway.

    PubMed

    Niu, Xiaofeng; Wang, Yu; Li, Weifeng; Zhang, Hailin; Wang, Xiumei; Mu, Qingli; He, Zehong; Yao, Huan

    2015-12-01

    Esculin, a coumarinic derivative found in Aesculus hippocastanum L. (Horse-chestnut), has been reported to have potent anti-inflammatory properties. The present study is designed to investigate the protective effects of esculin on various inflammation models in vivo and in vitro and to clarify the possible mechanism. Induced-animal models of inflammation and lipopolysaccharide (LPS)-challenged mouse peritoneal macrophages were used to examine the anti-inflammatory activity of esculin. In present study, xylene-induced mouse ear edema, carrageenan-induced rat paw edema, and carrageenan-induced mouse pleurisy were attenuated by esculin. In vitro, the pro-inflammatory cytokine levels of tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) in supernatant were reduced by esculin. Meanwhile, we found that esculin significantly inhibited LPS-induced activation of mitogen-activated protein kinase (MAPK) pathway in peritoneal macrophages. These results suggest that esculin has potent anti-inflammatory activities in vivo and in vitro, which may involve the inhibition of the MAPK pathway. Esculin may be a promising preventive agent for inflammatory diseases in human.

  4. Effect of Kramecyne on the Inflammatory Response in Lipopolysaccharide-Stimulated Peritoneal Macrophages

    PubMed Central

    Sánchez-Miranda, E.; Lemus-Bautista, J.; Pérez, S.; Pérez-Ramos, J.

    2013-01-01

    Kramecyne is a new peroxide, it was isolated from Krameria cytisoides, methanol extract, and this plant was mostly found in North and South America. This compound showed potent anti-inflammatory activity; however, the mechanisms by which this compound exerts its anti-inflammatory effect are not well understood. In this study, we examined the effects of kramecyne on inflammatory responses in mouse lipopolysaccharide- (LPS-) induced peritoneal macrophages. Our findings indicate that kramecyne inhibits LPS-induced production of tumor necrosis factor (TNF-α) and interleukin- (IL-) 6. During the inflammatory process, levels of cyclooxygenase- (COX-) 2, nitric oxide synthase (iNOS), and nitric oxide (NO) increased in mouse peritoneal macrophages; however, kramecyne suppressed them significantly. These results provide novel insights into the anti-inflammatory actions and support its potential use in the treatment of inflammatory diseases. PMID:23573152

  5. Regulation of LPS-induced mRNA expression of pro-inflammatory cytokines via alteration of NF-κB activity in mouse peritoneal macrophages exposed to fluoride.

    PubMed

    Tian, Yuhu; Huo, Meijun; Li, Guangsheng; Li, Yanyan; Wang, Jundong

    2016-10-01

    F toxicity to immune system, especially to macrophage, has been studied a lot recently. Nuclear factor-kappa B (NF-κB), as a transcription factor, plays a central role in immune and inflammatory responses via the regulation of downstream gene expression. Recent studies indicated that fluoride effect on inflammatory cytokine secretion, however, the molecular mechanism was less understood. In our study, peritoneal macrophages (PMs) were divided several groups and were administrated sodium fluoride (NaF, 50, 100, 200, 400, 800 μM) and/or lipopolysaccharide (LPS, 30 ng/mg). The mRNA expression of p65, inducible nitric oxide synthase (iNOS), tumor necrosis factor alpha (TNF-α) and interleukin-1 beta (IL-1β) in macrophages exposed to fluoride was determined by quantitative real-time RT-PCR respectively. The translocation of NF-κB from cytoplasm to nucleus, which in a way reflects NF-κB activity, was demonstrated by Immunofluorescence and ELISA. Our results showed that fluoride had a dose-dependent effect on NF-κB activity, which coincided with LPS-induced mRNA expression of its downstream genes, iNOS and IL-1β. Fluoride alone causes no effect on gene expression. However, the mRNA expression of TNF-α showed non-NF-κB-dependent manner. Therefore, we come to the conclusion that fluoride can regulate LPS-induced mRNA expression of iNOS and IL-1β via NF-κB pathway in mouse peritoneal macrophages.

  6. Metabolism Supports Macrophage Activation

    PubMed Central

    Langston, P. Kent; Shibata, Munehiko; Horng, Tiffany

    2017-01-01

    Macrophages are found in most tissues of the body, where they have tissue- and context-dependent roles in maintaining homeostasis as well as coordinating adaptive responses to various stresses. Their capacity for specialized functions is controlled by polarizing signals, which activate macrophages by upregulating transcriptional programs that encode distinct effector functions. An important conceptual advance in the field of macrophage biology, emerging from recent studies, is that macrophage activation is critically supported by metabolic shifts. Metabolic shifts fuel multiple aspects of macrophage activation, and preventing these shifts impairs appropriate activation. These findings raise the exciting possibility that macrophage functions in various contexts could be regulated by manipulating their metabolism. Here, we review the rapidly evolving field of macrophage metabolism, discussing how polarizing signals trigger metabolic shifts and how these shifts enable appropriate activation and sustain effector activities. We also discuss recent studies indicating that the mitochondria are central hubs in inflammatory macrophage activation. PMID:28197151

  7. Endomorphin-suppressed nitric oxide release from mice peritoneal macrophages.

    PubMed

    Balog, Tihomir; Sarić, Ana; Sobocanec, Sandra; Kusić, Borka; Marotti, Tatjana

    2010-02-01

    Endomorphins are newly discovered mu-opioid receptor selective immunocompetent opioid peptides. Endomorphin 1 is predominantly distributed in brain, while endomorphin 2 is widely allocated in the spinal cord. Lately, endomorphins have been investigated as modulators of reactive oxygen and nitrogen species. Nitric oxide is short lived radical involved in various biological processes such as regulation of blood vessel contraction, inflammation, neurotransmission and apoptosis. The aim of this work was to investigate the in vivo effects of endomorphins on nitric oxide release and NOS 2 isoenzyme upregulation in mice peritoneal macrophages additionally challenged ex vivo with lipopolysaccharide. The results showed that endomorphin 1 or endomorphin 2 in vitro did not change NO release from peritoneal mouse macrophages during a 48 h incubation period. On the other hand in vivo endomorphins had suppressive effect on NO release as well as on NOS 2 and IL-1 protein concentration. The most of suppressive effect in vivo of both endomorphins was blocked with 30 min pretreatment with mu-receptor selective antagonist beta-FNA, which proved involvement of opioid receptor pathway in suppressive effects of endomorphins.

  8. The galactose-recognizing system of rat peritoneal macrophages; identification and characterization of the receptor molecule.

    PubMed

    Kelm, S; Schauer, R

    1988-08-01

    Resident rat peritoneal macrophages express a galactose-recognizing system, which mediates binding and uptake of cells and glycoproteins exposing terminal galactose residues. Here we describe the identification, isolation, and characterization of the corresponding receptor molecule. Using photoaffinity labelling of adherent peritoneal macrophages with the 4-azido-6-125I-salicylic acid derivative of anti-freeze glycoprotein 8 followed by SDS-PAGE and autoradiography, we identified the receptor of these cells as a protein with an apparent molecular mass of 42 kDa. Furthermore, cell surface receptors were radioiodinated by an affinity-supported labelling technique using the conjugate of asialoorosomucoid and lactoperoxidase, followed by extraction and isolation by affinity chromatography. Finally, the native receptor was isolated and analysed. To estimate its binding activity in solutions, a suitable binding assay was developed, using the precipitation of receptor-ligand complex with polyethylene glycol to separate bound from unbound 125I-asialoorosomucoid, which was used as ligand. It is shown that the isolated receptor binds to galactose-exposing particles and distinguishes between sialidase-treated and -untreated erythrocytes, similar to peritoneal macrophages. The binding characteristics of the membrane-bound and the solubilized receptor are described in the following paper of Lee et al.

  9. Effects of selenizing angelica polysaccharide and selenizing garlic polysaccharide on immune function of murine peritoneal macrophage.

    PubMed

    Gao, Zhenzhen; Liu, Kuanhui; Tian, Weijun; Wang, Hongchao; Liu, Zhenguang; Li, Youying; Li, Entao; Liu, Cui; Li, Xiuping; Hou, Ranran; Yue, Chanjuan; Wang, Deyun; Hu, Yuanliang

    2015-07-01

    The effects of two selenizing polysaccharides (sCAP2 and sGPS6) on immune function of murine peritoneal macrophages taking two non-selenizing polysaccharides (CAP and GPS) and modifier Na2SeO3 as control. In vitro test, the changes of selenizing polysaccharides, non-selenizing polysaccharides and Na2SeO3 on murine macrophages function were evaluated by phagocytosis and nitric oxide (NO) secretion tests. In vivo test, the mice were injected respectively with 0.2, 0.4 and 0.6 mg of sCAP2, sGPS6, CAP and GPS, or Na2SeO3 80 μg or normal saline 0.4 mL. The peritoneal macrophages were collected and cultured to determine the contents of TNF-α, IL-6 and IL-10 in supernatants by enzyme-linked immunosorbent assay. The results showed that sCAP2 and sGPS6 could significantly promote the phagocytosis and secretion of NO and three cytokines of macrophages in comparison with CAP and GPS. sCAP2 possessed the strongest activity. This indicates that selenylation modification can further improve the immune-enhancing activity of polysaccharide, and sCAP2 could be as a new immunopotentiator.

  10. The equine alveolar macrophage: Functional and phenotypic comparisons with peritoneal macrophages☆

    PubMed Central

    Karagianni, Anna E.; Kapetanovic, Ronan; McGorum, Bruce C.; Hume, David A.; Pirie, Scott R.

    2013-01-01

    Alveolar macrophages (AMs) constitute the first line of defence in the lung of all species, playing a crucial role in the regulation of immune responses to inhaled pathogens. A detailed understanding of the function and phenotype of AMs is a necessary pre-requisite to both elucidating their role in preventing opportunistic bacterial colonisation of the lower respiratory tract and developing appropriate preventative strategies. The purpose of the study was to characterise this important innate immune cell at the tissue level by making functional and phenotypic comparisons with peritoneal macrophages (PMs). We hypothesised that the tissue of origin determines a unique phenotype of AMs, which may constitute an appropriate therapeutic target for certain equine respiratory diseases. Macrophages isolated from the lung and the peritoneal cavity of 9 horses were stimulated with various toll like receptor (TLR) ligands and the production of nitrite, tumour necrosis factor alpha (TNFα), interleukin (IL) 10 and indoleamine 2,3-dioxygenase (IDO) were measured by the Griess reaction and enzyme linked immunosorbent assay (ELISA) and/or quantitative polymerase chain reaction, respectively. Cells were also compared on the basis of phagocytic-capacity and the expression of several cell surface markers. AMs, but not PMs, demonstrated increased TNFα release following stimulation with LPS, polyinosinic polycytidylic acid (Poly IC) and heat-killed Salmonella typhinurium and increased TNFα and IDO mRNA expression when stimulated with LPS. AMs showed high expression of the specific macrophage markers cluster of differentiation (CD) 14, CD163 and TLR4, whereas PMs showed high expression of TLR4 only. AMs, but not PMs, demonstrated efficient phagocytic activity. Our results demonstrate that AMs are more active than PMs when stimulated with various pro-inflammatory ligands, thus supporting the importance of the local microenvironment in the activation status of the macrophage. This

  11. Intracellular multiplication of Paracoccidioides brasiliensis in macrophages: killing and restriction of multiplication by activated macrophages.

    PubMed Central

    Brummer, E; Hanson, L H; Restrepo, A; Stevens, D A

    1989-01-01

    The effect of coculturing yeast-form Paracoccidioides brasiliensis with murine cells was studied. Coculture of resident peritoneal or pulmonary macrophages with P. brasiliensis for 72 h dramatically enhanced fungal multiplication 19.3 +/- 2.4- and 4.7 +/- 0.8-fold, respectively, compared with cocultures with lymph node cells or complete tissue culture medium alone. Support of P. brasiliensis multiplication by resident peritoneal macrophages was macrophage dose dependent. Lysates of macrophages, supernatants from macrophage cultures, or McVeigh-Morton broth, like complete tissue culture medium, did not support multiplication of P. brasiliensis in 72-h cultures. Time course microscopic studies of cocultures in slide wells showed that macrophages ingested P. brasiliensis cells and that the ingested cells multiplied intracellularly. In sharp contrast to resident macrophages, lymphokine-activated peritoneal and pulmonary macrophages not only prevented multiplication but reduced inoculum CFU by 96 and 100%, respectively, in 72 h. Microscopic studies confirmed killing and digestion of P. brasiliensis ingested by activated macrophages in 48 h. These findings indicate that resident macrophages are permissive for intracellular multiplication of P. brasiliensis and that this could be a factor in pathogenicity. By contrast, activated macrophages are fungicidal for P. brasiliensis. Images PMID:2744848

  12. Anti-inflammatory action of γ-irradiated genistein in murine peritoneal macrophage

    NASA Astrophysics Data System (ADS)

    Sung, Nak-Yun; Byun, Eui-Baek; Song, Du-Sup; Jin, Yeung-Bae; Park, Jae-Nam; Kim, Jae-Kyung; Park, Jong-Heum; Song, Beom-Seok; Park, Sang-Hyun; Lee, Ju-Woon; Kim, Jae-Hun

    2014-12-01

    This present study was to examine the cytotoxicity and anti-inflammatory activity of gamma (γ)-irradiated genistein in murine peritoneal macrophage. Inflammation to macrophage was induced by adding the lipopolysaccharide (LPS). γ-Irradiated genistein significantly decreased the cytotoxicity to murine peritoneal macrophage in dose ranges from 5 to 10 μM than that of non-irradiated genistein. Anti-inflammatory activity within the doses less than 2 μM showed that γ-irradiated genistein treatment remarkably reduced the lipopolysaccharide-induced inflammation by decreasing the nitric oxide (NO) and cytokines (TNF-α, IL-6) production. In a structural analysis through the high pressure liquid chromatography (HPLC), γ-irradiated genistein showed a new peak production distinguished from main peak of genistein (non-irradiated). Therefore, increase of anti-inflammatory activity may closely mediate with structural changes induced by γ irradiation exposure. Based on the above result, γ-irradiation could be an effective tool for reduction of toxicity and increase of physiological activity of biomolecules.

  13. Killing of Pseudomonas pseudomallei by polymorphonuclear leukocytes and peritoneal macrophages from chicken, sheep, swine and rabbits.

    PubMed

    Markova, N; Kussovski, V; Radoucheva, T

    1998-07-01

    Differences in the kinetics of Pseudomonas pseudomallei killing by peritoneal macrophages (PM) and polymorphonuclear leucocytes (PMNL) from chickens, sheep, swine and rabbits were found. P. pseudomallei was rapidly killed by porcine PM and PMNL. However the bacterial killing by ovine and lapine PM and PMNL proceeded at a slower rate. In contrast, chicken PM and PMNL ingested and killed the lowest number of P. pseudomallei bacteria. The differences in the bactericidal activity of PM and PMNL from different animal species correlated with the level of their acid phosphatase and glycolytic activity.

  14. Chemotherapeutic agent CPT-11 eliminates peritoneal resident macrophages by inducing apoptosis.

    PubMed

    Huang, Mei-Yun; Pan, Hao; Liang, Yi-Dan; Wei, Hong-Xia; Xu, Li-Hui; Zha, Qing-Bing; He, Xian-Hui; Ouyang, Dong-Yun

    2016-02-01

    CPT-11 (Irinotecan) is a first-line chemotherapeutic agent in clinic, but it may induce side effects including diarrhea and enteritis in patients. The underlying mechanism of CPT-11's intestinal toxicity is unclear. Peritoneal resident macrophages have been reported to be important for the maintenance of intestinal homeostasis. In this study, we evaluated the cytotoxic effects of CPT-11 on mouse peritoneal resident macrophages. CPT-11 was administered intraperitoneally to mice and their peritoneal exudate cells were isolated for evaluation. CPT-11 treatment strikingly decreased the ratio of F4/80(hi)MHCII(low) large peritoneal macrophages (LPMs), which are regarded as prenatally-originated peritoneal resident macrophages. Consistent with this, the transcription factor GATA6 specifically expressed in LPMs was barely detectable in the macrophages from CPT-11-treated mice, indicative of elimination of LPMs. Such elimination of LPMs was at least partly due to CPT-induced apoptosis in macrophages, because inhibition of apoptosis by caspase-3 inhibitor z-DEVD-fmk significantly diminished the loss of GATA6(+) LPMs. As GATA6 is a transcription factor that controls expression of multiple genes regulating peritoneal B-1 cell development and translocation, elimination of GATA6(+) LPMs led to a great reduction in B-1 cells in the peritoneal cavity after CPT-11 treatment. These results indicated that CPT-11-induced apoptosis contributed to the elimination of peritoneal resident macrophages, which might in turn impair the function of peritoneal B-1 cells in maintaining intestinal homeostasis. Our findings may at least partly explain why CPT-11 treatment in cancer patients induces diarrhea and enteritis, which may provide a novel avenue to prevent such side effects.

  15. TNF-alpha, produced by feline infectious peritonitis virus (FIPV)-infected macrophages, upregulates expression of type II FIPV receptor feline aminopeptidase N in feline macrophages.

    PubMed

    Takano, Tomomi; Hohdatsu, Tsutomu; Toda, Ayako; Tanabe, Maki; Koyama, Hiroyuki

    2007-07-20

    The pathogenicity of feline infectious peritonitis virus (FIPV) is known to depend on macrophage tropism, and this macrophage infection is enhanced by mediation via anti-S antibody (antibody-dependent enhancement, ADE). In this study, we found that TNF-alpha production was increased with viral replication in macrophages inoculated with a mixture of FIPV and anti-S antibody, and demonstrated that this culture supernatant had feline PBMC apoptosis-inducing activity. We also demonstrated that the expression level of the FIPV virus receptor, feline aminopeptidase N (fAPN), was increased in macrophages of FIP cats. For upregulation of TNF-alpha and fAPN in macrophages, viral replication in macrophages is necessary, and their expressions were increased by ADE of FIPV infection. It was demonstrated that a heat-resistant fAPN-inducing factor was present in the culture supernatant of FIPV-infected macrophages, and this factor was TNF-alpha: fAPN expression was upregulated in recombinant feline TNF-alpha-treated macrophages, and FIPV infectivity was increased in these macrophages. These findings suggested that FIPV replication in macrophages increases TNF-alpha production in macrophages, and the produced TNF-alpha acts and upregulates fAPN expression, increasing FIPV sensitivity.

  16. Salvianolic Acid A Attenuates Cell Apoptosis, Oxidative Stress, Akt and NF-κB Activation in Angiotensin-II Induced Murine Peritoneal Macrophages.

    PubMed

    Li, Ling; Xu, Tongda; Du, Yinping; Pan, Defeng; Wu, Wanling; Zhu, Hong; Zhang, Yanbin; Li, Dongye

    2016-01-01

    We discuss the role of Salvianolic acid A(SAA), one of the main effective components in Salvia Miltiorrhiza (known as 'Danshen' in traditional Chinese medicine), in apoptotic factors, the production of oxidative products, and the expression of Akt and NF-κB in angiotensin II (Ang II)-mediated murine macrophages. In the present study, Ang II was added to mice abdominal macrophages with or without addition of SAA. After cell identification, apoptosis was measured by DNA strand break level with TdT-mediated dUTP nick-end labeling (TUNEL) staining, and the expression of Bcl-2 and Bax. Intracellular concentrations of superoxide dismutase (SOD) and malondialdehyde (MDA) were also measured. Western blotting determined the expression of Akt, p-Akt, NF-κB and p-NF-κB. Ly294002 (the inhibitor of PI3K) was used to determine the mechanism of SAA. Ang II (1 µM) significantly increased the number of TUNEL-positive cells and Bax expression, but reduced Bcl-2 expression. These effects were antagonized when the cells were pretreated with SAA. SAA decreased MDA, but increased SOD in the cell lysis solution treated with Ang II. It markedly reduced the level of p-NF-κB, as also p-Akt, which was partly blocked by Ly294002. SAA prevents Ang IIinduced apoptosis, oxidative stress and related protein expression in the macrophages. It also inhibits the activation of Akt.

  17. Immunocytochemical demonstration of feline infectious peritonitis virus within cerebrospinal fluid macrophages.

    PubMed

    Ives, Edward J; Vanhaesebrouck, An E; Cian, Francesco

    2013-12-01

    A 4-month-old female entire domestic shorthair cat presented with an acute onset of blindness, tetraparesis and subsequent generalised seizure activity. Haematology and serum biochemistry demonstrated a moderate, poorly regenerative anaemia, hypoalbuminaemia and hyperglobulinaemia with a low albumin:globulin ratio. Serology for feline coronavirus antibody was positive with an elevated alpha-1 acid glycoprotein. Analysis of cisternal cerebrospinal fluid (CSF) demonstrated markedly elevated protein and a mixed, predominately neutrophilic pleocytosis. Immunocytochemistry for feline coronavirus was performed on the CSF, with positive staining observed inside macrophages. The cat was subsequently euthanased, and both histopathology and immunohistochemistry were consistent with a diagnosis of feline infectious peritonitis. This is the first reported use of immunocytochemistry for detection of feline coronavirus within CSF macrophages. If this test proves highly specific, as for identification of feline coronavirus within tissue or effusion macrophages, it would be strongly supportive of an ante-mortem diagnosis of feline infectious peritonitis in cats with central nervous system involvement without the need for biopsy.

  18. A role for connexin43 in macrophage phagocytosis and host survival after bacterial peritoneal infection.

    PubMed

    Anand, Rahul J; Dai, Shipan; Gribar, Steven C; Richardson, Ward; Kohler, Jeff W; Hoffman, Rosemary A; Branca, Maria F; Li, Jun; Shi, Xiao-Hua; Sodhi, Chhinder P; Hackam, David J

    2008-12-15

    The pathways that lead to the internalization of pathogens via phagocytosis remain incompletely understood. We now demonstrate a previously unrecognized role for the gap junction protein connexin43 (Cx43) in the regulation of phagocytosis by macrophages and in the host response to bacterial infection of the peritoneal cavity. Primary and cultured macrophages were found to express Cx43, which localized to the phagosome upon the internalization of IgG-opsonized particles. The inhibition of Cx43 using small interfering RNA or by obtaining macrophages from Cx43 heterozygous or knockout mice resulted in significantly impaired phagocytosis, while transfection of Cx43 into Fc-receptor expressing HeLa cells, which do not express endogenous Cx43, conferred the ability of these cells to undergo phagocytosis. Infection of macrophages with adenoviruses expressing wild-type Cx43 restored phagocytic ability in macrophages from Cx43 heterozygous or deficient mice, while infection with viruses that expressed mutant Cx43 had no effect. In understanding the mechanisms involved, Cx43 was required for RhoA-dependent actin cup formation under adherent particles, and transfection with constitutively active RhoA restored a phagocytic phenotype after Cx43 inactivation. Remarkably, mortality was significantly increased in a mouse model of bacterial peritonitis after Cx43 inhibition and in Cx43 heterozygous mice compared with untreated and wild-type counterparts. These findings reveal a novel role for Cx43 in the regulation of phagocytosis and rearrangement of the F-actin cytoskeleton, and they implicate Cx43 in the regulation of the host response to microbial infection.

  19. Differential turnover of phospholipid acyl groups in mouse peritoneal macrophages

    SciTech Connect

    Kuwae, T.; Schmid, P.C.; Johnson, S.B.; Schmid, H.H. )

    1990-03-25

    Phospholipid acyl turnover was assessed in mouse peritoneal exudate cells which consisted primarily of macrophages. The cells were incubated for up to 5 h in media containing 40% H218O, and uptake of 18O into ester carbonyls of phospholipids was determined by gas chromatography-mass spectrometry of hydrogenated methyl esters. The uptake was highest in choline phospholipids and phosphatidylinositol, less in ethanolamine phospholipids, and much less in phosphatidylserine. Acyl groups at the sn-1 and sn-2 positions of diacyl glycerophospholipids, including arachidonic and other long-chain polyunsaturated fatty acids, acquired 18O at about the same rate. Acyl groups of alkylacyl glycerophosphocholine exhibited lower rates of 18O uptake, and acyl groups of ethanolamine plasmalogens (alkenylacyl glycerophosphoethanolamines) acquired only minimal amounts of 18O within 5 h, indicating a low average acyl turnover via free fatty acids. Pulse experiments with exogenous 3H-labeled arachidonic acid supported the concept that acylation of alkenyl glycerophosphoethanolamine occurs by acyl transfer from other phospholipids rather than via free fatty acids and acyl-CoA. The 18O content of intracellular free fatty acids increased gradually over a 5-h period, whereas in extracellular free fatty acids it reached maximal 18O levels within the first hour. Arachidonate and other long-chain polyunsaturated fatty acids were found to participate readily in deacylation-reacylation reactions but were present only in trace amounts in the free fatty acid pools inside and outside the cells. We conclude that acyl turnover of macrophage phospholipids through hydrolysis and reacylation is rapid but tightly controlled so that appreciable concentrations of free arachidonic acid do not occur.

  20. Resident peritoneal leukocytes are important sources of MMP-9 during zymosan peritonitis: superior contribution of macrophages over mast cells.

    PubMed

    Kolaczkowska, Elzbieta; Lelito, Monika; Kozakiewicz, Elzbieta; van Rooijen, Nico; Plytycz, Barbara; Arnold, Bernd

    2007-11-15

    Metalloproteinase 9 (MMP-9) is crucial for normal neutrophil infiltration into zymosan-inflamed peritoneum. During the course of zymosan peritonitis MMP-9 is produced in a biphasic-manner as its presence is detectable as early as 30 min post zymosan and then between 2 and 8 h of inflammation. As inflammatory leukocytes were shown to produce MMP-9 we asked if also resident leukocytes, mast cells and macrophages, contribute to its production. And furthermore, if their contribution is limited only to the early phase of inflammation or extends to the later stages. For this purpose some mice were depleted of either resident macrophages or functional mast cells and expression of MMP-9 in peritoneal leukocytes and its release to the exudate were monitored. It turned out that depletion of peritoneal macrophages decreased both MMP-9 content in the leukocytes and its release to the inflammatory exudate at 30 min and 6h of peritonitis. The functional depletion of mast cells also caused a significant decrease in the production/release of MMP-9 that was especially apparent at the early time point (30 min). Moreover, the study shows concomitant kinetics of MMP-9 expression in leukocytes and its release to the exudatory fluid. The findings indicate that resident tissue leukocytes, and among them especially macrophages, constitute an important source of MMP-9 during acute peritoneal inflammation. Overall, the study shows that resident tissue leukocytes, mostly macrophages, constitute an important cellular source(s) of inflammation-related factors and should be regarded as possible targets of anti-inflammatory treatment.

  1. The immunomodulatory effects of 3-monochloro-1,2-propanediol on murine splenocyte and peritoneal macrophage function in vitro.

    PubMed

    Byun, Jung A; Ryu, Mi Hyun; Lee, Jong Kwon

    2006-04-01

    3-Monochloro-1,2-propanediol (MCPD) is a well-known by-product of acid-hydrolyzed soy sauce during its manufacturing process. MCPD has been reported genotoxic in vitro, and reproductive toxicity and carcinogenicity in rats. To evaluate the immunomodulatory effect of MCPD on murine splenocyte and macrophage in vitro, we investigated splenocyte blastogenesis by concanavalin A (Con A), anti-CD3, and lipopolyssacharide (LPS), the production of cytokines from splenocyte, and the activity of mouse peritoneal macrophages. There was a significant decrease in lymphocyte blastogenesis to Con A or anti-CD3 at subtoxic dose of MCPD. A significant decrease in splenocyte blastogenesis to LPS was also observed. The production level of interferon (IFN)-gamma on splenocyte culture with Con A was significantly reduced at the higher concentration than 1.0mM of MCPD. The levels of interleukin (IL)-4 and IL-10 were also decreased at high concentrations of MCPD. There was a significant decrease in production of nitric oxide (NO) by peritoneal macrophages treated with MCPD. MCPD also inhibits tumor necrosis factor (TNF)-alpha production of stimulated macrophages. These results indicate that MCPD might be able to reduce the functionality of lymphocytes and peritoneal macrophages in vitro.

  2. Macrophage activation and polarization.

    PubMed

    Martinez, Fernando Oneissi; Sica, Antonio; Mantovani, Alberto; Locati, Massimo

    2008-01-01

    Macrophages are widely distributed immune system cells that play an indispensable role in homeostasis and defense. They can be phenotypically polarized by the microenvironment to mount specific functional programs. Polarized macrophages can be broadly classified in two main groups: classically activated macrophages (or M1), whose prototypical activating stimuli are IFNgamma and LPS, and alternatively activated macrophages (or M2), further subdivided in M2a (after exposure to IL-4 or IL-13), M2b (immune complexes in combination with IL-1beta or LPS) and M2c (IL-10, TGFbeta or glucocorticoids). M1 exhibit potent microbicidal properties and promote strong IL-12-mediated Th1 responses, whilst M2 support Th2-associated effector functions. Beyond infection M2 polarized macrophages play a role in resolution of inflammation through high endocytic clearance capacities and trophic factor synthesis, accompanied by reduced pro-inflammatory cytokine secretion. Similar functions are also exerted by tumor-associated macrophages (TAM), which also display an alternative-like activation phenotype and play a detrimental pro-tumoral role. Here we review the main functions of polarized macrophages and discuss the perspectives of this field.

  3. Differential responses of rat alveolar and peritoneal macrophages to man-made vitreous fibers in vitro.

    PubMed

    Dörger, M; Münzing, S; Allmeling, A M; Messmer, K; Krombach, F

    2001-03-01

    Different approaches, including inhalation and intraperitoneal injection assays, have been used to assess the potential health effects of man-made vitreous fibers (MMVF). The purpose of this study was to compare the phagocytic activity and the formation of reactive oxygen species by rat alveolar macrophages (AM) and peritoneal macrophages (PM) upon exposure to MMVF10 glass wool and MMVF21 rock wool fibers. Macrophage (Mphi) phagocytosis of mineral fibers was assessed by optical videomicroscopy and computer-aided image analysis. Mphi were classified as cells not associated with fibers, cells with attached fibers, cells with incompletely phagocytized fibers (an appearance known as "frustrated phagocytosis"), and cells with completely phagocytized fibers. The production of superoxide anions by AM and PM upon incubation with MMVF10 and MMVF21 fibers was determined by the superoxide dismutase-inhibitable reduction of ferricytochrome C. PM were found to have a lower phagocytic activity than AM. A significantly higher percentage of AM than of PM underwent frustrated phagocytosis of MMVF10 and MMVF21 fibers. In line with these findings, AM generated higher levels of oxygen radicals than PM upon exposure to MMVF21 fibers. In contrast, MMVF10 fibers failed to induce the generation of reactive oxygen species by both AM and PM. Our in vitro results show that the phagocytic activity, in particular the frustrated phagocytosis of mineral fibers, was significantly lower in PM than in AM. The data support the idea that the durability and biopersistence of mineral fibers are higher in the peritoneal cavity than in the lung.

  4. Peritonitis

    MedlinePlus

    Acute abdomen; Spontaneous bacterial peritonitis; SBP; Cirrhosis - spontaneous peritonitis ... blood, body fluids, or pus in the belly ( abdomen ). One type is called spontaneous bacterial peritonitis (SPP). ...

  5. Aqueous extract of Gracilaria tenuistipitata suppresses LPS-induced NF-κB and MAPK activation in RAW 264.7 and rat peritoneal macrophages and exerts hepatoprotective effects on carbon tetrachloride-treated rat.

    PubMed

    Tseng, Chin-Kai; Lin, Chun-Kuang; Chang, Hsueh-Wei; Wu, Yu-Hsuan; Yen, Feng-Lin; Chang, Fang-Rong; Chen, Wei-Chun; Yeh, Chi-Chen; Lee, Jin-Ching

    2014-01-01

    In addition to the previous investigations of bioactivity of aqueous extract of the edible Gracilaria tenuistipitata (AEGT) against H2O2-induced DNA damage and hepatitis C virus replication, the purpose of this study is to evaluate the potential therapeutic properties of AEGT against inflammation and hepatotoxicity using lipopolysaccharide (LPS)-stimulated mouse RAW 264.7 cells, primary rat peritoneal macrophages and carbon tetrachloride (CCl4)-induced acute hepatitis model in rats. AEGT concentration-dependently inhibited the elevated RNA and protein levels of inducible nitric oxide synthase and cyclooxygenase-2, thereby reducing nitric oxide and prostaglandin E2 levels, respectively. Moreover, AEGT significantly suppressed the production of LPS-induced proinflammatory cytokines, including interleukin (IL)-1β, IL-6 and tumor necrosis factor-α. These inhibitory effects were associated with the suppression of nuclear factor-kappa B activation and mitogen-activated protein kinase phosphorylation by AEGT in LPS-stimulated cells. In addition, we highlighted the hepatoprotective and curative effects of AEGT in a rat model of CCl4-intoxicated acute liver injury, which was evident from reduction in the elevated serum aspartate aminotransferase and alanine aminotransferase levels as well as amelioration of histological damage by pre-treatment or post-treatment of AEGT. In conclusion, the results demonstrate that AEGT may serve as a potential supplement in the prevention or amelioration of inflammatory diseases.

  6. Aqueous Extract of Gracilaria tenuistipitata Suppresses LPS-Induced NF-κB and MAPK Activation in RAW 264.7 and Rat Peritoneal Macrophages and Exerts Hepatoprotective Effects on Carbon Tetrachloride-Treated Rat

    PubMed Central

    Tseng, Chin-Kai; Lin, Chun-Kuang; Chang, Hsueh-Wei; Wu, Yu-Hsuan; Yen, Feng-Lin; Chang, Fang-Rong; Chen, Wei-Chun; Yeh, Chi-Chen; Lee, Jin-Ching

    2014-01-01

    In addition to the previous investigations of bioactivity of aqueous extract of the edible Gracilaria tenuistipitata (AEGT) against H2O2-induced DNA damage and hepatitis C virus replication, the purpose of this study is to evaluate the potential therapeutic properties of AEGT against inflammation and hepatotoxicity using lipopolysaccharide (LPS)-stimulated mouse RAW 264.7 cells, primary rat peritoneal macrophages and carbon tetrachloride (CCl4)-induced acute hepatitis model in rats. AEGT concentration-dependently inhibited the elevated RNA and protein levels of inducible nitric oxide synthase and cyclooxygenase-2, thereby reducing nitric oxide and prostaglandin E2 levels, respectively. Moreover, AEGT significantly suppressed the production of LPS-induced proinflammatory cytokines, including interleukin (IL)-1β, IL-6 and tumor necrosis factor-α. These inhibitory effects were associated with the suppression of nuclear factor-kappa B activation and mitogen-activated protein kinase phosphorylation by AEGT in LPS-stimulated cells. In addition, we highlighted the hepatoprotective and curative effects of AEGT in a rat model of CCl4-intoxicated acute liver injury, which was evident from reduction in the elevated serum aspartate aminotransferase and alanine aminotransferase levels as well as amelioration of histological damage by pre-treatment or post-treatment of AEGT. In conclusion, the results demonstrate that AEGT may serve as a potential supplement in the prevention or amelioration of inflammatory diseases. PMID:24475143

  7. In vitro time-dependent vancomycin-resistant Staphylococcus aureus-induced free radical generation and status of antioxidant enzymes in murine peritoneal macrophage.

    PubMed

    Chakraborty, Subhankari Prasad; Mahapatra, Santanu Kar; Roy, Somenath

    2012-01-01

    Staphylococcus aureus is most frequently isolated pathogen causing bloodstream infections, skin and soft tissue infections, and pneumonia. The immune cells use reactive oxygen species (ROS) for carrying out their normal functions, while an excess amount of ROS can attack cellular components that lead to cell damage. The aim of the present study was to evaluate the free radical generation and status of the antioxidant enzymes in murine peritoneal macrophage during in vitro vancomycin-resistant S. aureus (VRSA) treatment with different time intervals. Peritoneal macrophages were treated with 5 × 10(6) colony-forming units (CFU)/mL VRSA cell suspension in vitro for different time intervals (1, 2, 3, 6, 12, and 24 h), and superoxide anion generation, nicotinamide adenine dinucleotide phosphate (NADPH) oxidase activity, myeloperoxidase (MPO) activity, nitric oxide (NO) generation, antioxidant enzyme status, and components of glutathione cycle were analyzed. Superoxide anion generation, NADPH oxidase activity, MPO activity, and NO generation got peak at 3 h indicates maximum free radical generation through activation of NADPH oxidase in murine peritoneal macrophages during VRSA infection. Reduced glutathione level, glutathione peroxidase, glutathione reductase, and glutathione S-transferase activity were decreased significantly (P < 0.05) with increasing time of VRSA infection. But the oxidized glutathione level was time-dependently increased significantly (P < 0.05) in murine peritoneal macrophages. All the changes in peritoneal macrophages after 3 h in vitro VRSA treatment had no significant difference. From this study, it may be summarized that in vitro VRSA infection not only generates excess free radical but also affects the antioxidant status and glutathione cycle in murine peritoneal macrophages.

  8. Anti-Inflammatory Effects of Hyptis albida Chloroform Extract on Lipopolysaccharide-Stimulated Peritoneal Macrophages

    PubMed Central

    Sánchez Miranda, Elizabeth; Pérez Ramos, Julia; Fresán Orozco, Cristina; Zavala Sánchez, Miguel Angel; Pérez Gutiérrez, Salud

    2013-01-01

    We examined the effects of a chloroform extract of Hyptis albida (CHA) on inflammatory responses in mouse lipopolysaccharide (LPS) induced peritoneal macrophages. Our findings indicate that CHA inhibits LPS-induced production of tumor necrosis factor (TNF-α) and interleukin-6 (IL-6). During the process, levels of cyclooxygenase-2 (COX-2), nitric oxide synthase (iNOS), and nitric oxide (NO) increased in the mouse peritoneal macrophages; however, the extract suppressed them significantly. These results provide novel insights into the anti-inflammatory actions of CHA and support its potential use in the treatment of inflammatory diseases. PMID:23970974

  9. Functional modifications of macrophage activity after sublethal irradiation. [Toxoplasma gondii

    SciTech Connect

    Swartz, R.P.

    1982-01-01

    The modifications of macrophage activity following sublethal irradiation, both in vivo and in vitro, were studied using spreading and C3b-receptor-mediated ingestion assays. Nonelicited peritoneal washout cells were examined for changes in activity and selected population characteristics. The cells from irradiated mice were from a resident peritoneal population and not immigrating cells. The macrophage population showed enhanced activity early with a refractory period (24-48) when the macrophages were unresponsive to stimulation by irradiated lymphocytes. The enhanced activity was inversely dose dependent on macrophage. The lymphocytes showed a regulatory function(s) on the time post irradiation at which they were examined. Early lymphocytes exhibited the ability to enhance the activity of normal macrophages while lymphocytes removed 24 hours post irradiation could suppress the activity of already activated macrophages. The effect(s) of the various lymphocyte populations were reproduced with cell-free supernatants which was indicative of the production of lymphokines. Separation on nylon wool columns indicated that the activity resided primarily in the T-cell population of lymphocytes. In vitro irradiation indicated that stimulation of the lymphocytes is macrophage dependent. Additional work indicated that sublethally irradiated macrophages did not inhibit replication of the coccidian protozoon Toxoplasma gondii although they did show increased phagocytosis. Examination of the serum from whole body irradiated mice showed the presence of a postirradiation substance which enhanced the phagocytosis of normal macrophages. It was not present in the serum of normal mice and was not endotoxin.

  10. Evidence that Resorption of Bone by Rat Peritoneal Macrophages Occurs in an Acidic Environment

    NASA Technical Reports Server (NTRS)

    Blair, H. C.

    1985-01-01

    Skeletal loss in space, like any form of osteoporosis, reflects a relative imbalance of the activities of cells resorbing (degrading) or forming bone. Consequently, prevention of weightlessness induced bone loss may theoretically be accomplished by (1) stimulating bone formation or (2) inhibiting bone resorption. This approach, however, requires fundamental understanding of the mechanisms by which cells form or degrade bone, information not yet at hand. An issue central to bone resorption is the pH at which resorption takes place. The pH dependent spectral shift of a fluorescent dye (fluorescein isothiocyanate) conjugated to bone matrix was used to determine the pH at the resorptive cell bone matrix interface. Devitalized rat bone was used as the substrate, and rat peritoneal macrophages were used as the bone resorbing cells. The results suggest that bone resorption is the result of generation of an acidic microenvironment at the cell matrix junction.

  11. CD4-Positive T Cells and M2 Macrophages Dominate the Peritoneal Infiltrate of Patients with Encapsulating Peritoneal Sclerosis

    PubMed Central

    Habib, Sayed M.; Abrahams, Alferso C.; Korte, Mario R.; Zietse, Robert; de Vogel, Lisette L.; Boer, Walther H.; Dendooven, Amélie; Clahsen-van Groningen, Marian C.; Betjes, Michiel G. H.

    2015-01-01

    Background Encapsulating peritoneal sclerosis (EPS) is a severe complication of peritoneal dialysis (PD). Previously, it has been shown that infiltrating CD4-positive T cells and M2 macrophages are associated with several fibrotic conditions. Therefore, the characteristics of the peritoneal cell infiltrate in EPS may be of interest to understand EPS pathogenesis. In this study, we aim to elucidate the composition of the peritoneal cell infiltrate in EPS patients and relate the findings to clinical outcome. Study Design, Setting, and Participants We studied peritoneal membrane biopsies of 23 EPS patients and compared them to biopsies of 15 PD patients without EPS. The cellular infiltrate was characterized by immunohistochemistry to detect T cells(CD3-positive), CD4-positive (CD4+) and CD8-positive T cell subsets, B cells(CD20-positive), granulocytes(CD15-positive), macrophages(CD68-positive), M1(CD80-positive), and M2(CD163-positive) macrophages. Tissues were analysed using digital image analysis. Kaplan-Meier survival analysis was performed to investigate the survival in the different staining groups. Results The cellular infiltrate in EPS biopsies was dominated by mononuclear cells. For both CD3 and CD68, the median percentage of area stained was higher in biopsies of EPS as opposed to non-EPS patients (p<0.001). EPS biopsies showed a higher percentage of area stained for CD4 (1.29%(0.61-3.20)) compared to CD8 (0.71%(0.46-1.01), p = 0.04), while in the non-EPS group these cells were almost equally represented (respectively 0.28%(0.05-0.83) versus 0.22%(0.17-0.43), p = 0.97). The percentage of area stained for both CD80 and CD163 was higher in EPS than in non-EPS biopsies (p<0.001), with CD163+ cells being the most abundant phenotype. Virtually no CD20-positive and CD15-positive cells were present in biopsies of a subgroup of EPS patients. No relation was found between the composition of the mononuclear cell infiltrate and clinical outcome. Conclusions A

  12. Anti-inflammatory effect of tetrahydrocoptisine from Corydalis impatiens is a function of possible inhibition of TNF-α, IL-6 and NO production in lipopolysaccharide-stimulated peritoneal macrophages through inhibiting NF-κB activation and MAPK pathway.

    PubMed

    Li, Weifeng; Huang, Huimin; Zhang, Yanmin; Fan, Ting; Liu, Xia; Xing, Wei; Niu, Xiaofeng

    2013-09-05

    The extracts or constituents from Corydalis impatiens are known to have many pharmacological activities. Tetrahydrocoptisine (THC), a protoberberine compound from Corydalis impatiens, was found to possess a potent anti-inflammatory effect in different acute or chronic inflammation model animals. Pretreatment with THC (i.p.) inhibited the paw and ear edema in the carrageenan-induced paw edema assay and xylene-induced ear edema assay, respectively. In the lipopolysaccharide (LPS)-induced systemic inflammation model, THC significantly inhibited serum tumor necrosis factor-alpha (TNF-α) release in mice. To clarify its possible molecular mechanisms underlying this anti-inflammatory effect, we investigated the effect of THC on LPS-induced responses in peritoneal macrophages. Our data demonstrated that THC significantly inhibited LPS-induced TNF-α, interleukin-6(IL-6) and nitric oxide (NO) production. THC inhibited the production of TNF-α and IL-6 by down-regulating LPS-induced IL-6 and TNF-α mRNA expression. Furthermore, it attenuated the phosphorylation of p38 mitogen-activated protein kinase (p38MAPK) and phosphorylation of extracellular signal-regulated kinase1/2 (ERK1/2) as well as the expression of nuclear factor kappa B(NF-κB), in a concentration-dependent manner. Taken together, our data suggest that THC is an active anti-inflammatory constituent by inhibition of TNF-α, IL-6 and NO production possibly via down-regulation of NF-κB activation, phospho-ERK1/2 and phospho-p38MAPK signal pathways.

  13. Cl-IB-MECA enhances TNF-α release in peritoneal macrophages stimulated with LPS.

    PubMed

    Forte, Giovanni; Sorrentino, Rosalinda; Montinaro, Antonella; Pinto, Aldo; Morello, Silvana

    2011-05-01

    Adenosine receptor A3 (A3R) belongs to the Gi/Gq-coupled receptor family, that leads to the intracellular cAMP reduction and intracellular calcium increase, respectively. A3R is widely expressed and it can play a crucial role in many patho-physiological conditions, including inflammation. Here we investigate the effect of Cl-IB-MECA, A3R agonist, on the production of TNF-α. We found that Cl-IB-MECA enhances LPS-induced TNF-α release in peritoneal macrophages. This effect is reduced by MRS1191, A3R antagonist and by forskolin, activator of adenylyl cyclase. pIκBα increased in LPS+Cl-IB-MECA-treated macrophages, while total IκB kinase-β (IKKβ) reduced. Indeed, p65NF-κB nuclear translocation increased in cells treated with LPS+Cl-IB-MECA. Moreover, IMD 0354, IKKβ inhibitor, significantly abrogated the effect of Cl-IB-MECA on TNF-α release. Inhibition of protein kinase C (PKC) significantly reduced Cl-IB-MECA-induced TNF-α release in LPS-stimulated macrophages. Furthermore, LY-294002, PI3K inhibitor, reduced the TNF-α production enhanced by Cl-IB-MECA, although the phosphorylation status of Akt did not change in cells treated with LPS+Cl-IB-MECA than LPS alone. In summary, these data show that Cl-IB-MECA is able to enhance TNF-α production in LPS-treated macrophages in an NF-κB- dependent manner.

  14. Dynamics of lung macrophage activation in response to helminth infection

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Most of our understanding of the development and phenotype of alternatively activated macrophages (AAM) has been obtained from studies investigating the response of bone marrow- and peritoneal-derived cells to IL-4 or IL-13 stimulation. Comparatively little is known about the development of the AAM...

  15. Isoalantolactone inhibits LPS-induced inflammation via NF-κB inactivation in peritoneal macrophages and improves survival in sepsis.

    PubMed

    He, Guodong; Zhang, Xu; Chen, Yanhua; Chen, Jing; Li, Li; Xie, Yubo

    2017-04-10

    Sepsis, a clinical syndrome occurring in patients following infection or injury, is a leading cause of mortality worldwide. It involves uncontrolled inflammatory response resulting in multi-organ failure and even death. Isoalantolactone (IAL), a sesquiterpene lactone, is known for its anti-cancer effects. Nevertheless, little is known about the anti-inflammatory effects of IAL, and the role of IAL in sepsis is unclear. In this study, we demonstrated that IAL decreased lipopolysaccharide (LPS)-mediated production of nitric oxide, PEG2 and cytokines (IL-6, TNF-α) in peritoneal macrophages and RAW 264.7 macrophages. Moreover, molecular mechanism studies indicated that IAL plays an anti-inflammatory role by inhibiting LPS-induced activation of NF-κB pathway in peritoneal macrophages. In vivo, IAL reduced the secretion of IL-6 and TNF-α in serum, and increased the survival rate of mice with LPS-induced sepsis. In addition, IAL attenuated the activation of NF-κB pathway in liver. Taken together, our data suggest that IAL may represent a potentially new drug candidate for the treatment of sepsis.

  16. Anti-inflammatory effects of miR-21 in the macrophage response to peritonitis.

    PubMed

    Barnett, Rebecca Elise; Conklin, Daniel J; Ryan, Lindsey; Keskey, Robert C; Ramjee, Vikram; Sepulveda, Ernesto A; Srivastava, Sanjay; Bhatnagar, Aruni; Cheadle, William G

    2016-02-01

    We investigated the role of microRNA-21 in the macrophage response to peritonitis; microRNA-21 expression increases in peritoneal macrophages after lipopolysaccharide stimulation but is delayed until 48 hours after cecal ligation and puncture. MicroRNA-21-null mice and bone marrow-derived cell lines were exposed to cecal ligation and puncture or lipopolysaccharide, and survival, microRNA-21 levels, target messenger RNAs and proteins, and cytokines were assayed. Macrophages were also transfected with microRNA-21 mimics and antagomirs, and similar endpoints were measured. Survival in microRNA-21-null mice was significantly decreased after lipopolysaccharide-induced peritonitis but unchanged after cecal ligation and puncture compared with similarly treated wild-type mice. MicroRNA-21 expression, tumor necrosis factor-α, interleukin 6, and programmed cell death protein 4 levels were increased after lipopolysaccharide addition in peritoneal cells. Pelino1 and sprouty (SPRY) messenger RNAs were similarly increased early, whereas programmed cell death protein 4 messenger RNA was decreased after lipopolysaccharide, and all microR-21 target messenger RNAs were subsequently decreased by 24 hours after lipopolysaccharide. Transfection with mimics and antagomirs led to appropriate responses in microRNA-21 and tumor necrosis factor-α. Knockdown of microRNA-21 in bone marrow-derived cells showed increased tumor necrosis factor-α and decreased interleukin 10 in response to lipopolysaccharide. Target proteins were unaffected by knockdown as was extracellular signal-regulated kinase; however, the nuclear factor κB p65 subunit was increased after lipopolysaccharide in the microRNA-21 knockout cells. In contrast, there was little change in these parameters after cecal ligation and puncture induction between null and wild-type mice. MicroRNA-21 is beneficial to survival in mice following lipopolysaccharide peritonitis. Overexpression of microRNA-21 decreased tumor necrosis factor

  17. Modulation of phagocytic function in murine peritoneal macrophages by bombesin, gastrin-releasing peptide and neuromedin C.

    PubMed Central

    De la Fuente, M; Del Rio, M; Ferrandez, M D; Hernanz, A

    1991-01-01

    Bombesin, as well as the two mammalian bombesin-like peptides gastrin-releasing peptide and neuromedin C, have been shown in this study to stimulate in vitro all steps of the phagocytic process in murine peritoneal macrophages: adherence to substrate, chemotaxis, ingestion of cells (Candida albicans) and inert particles (latex beads), and production of superoxide anion as measured by nitroblue tetrazolium reduction. A dose-response relationship was observed, with maximal stimulation of phagocytic process between 10(-12)M and 10(-9)M. Gastrin-releasing peptide (GRP) and neuromedin C caused a higher activation of adherence, chemotaxis and ingestion of C. albicans than bombesin. The three neuropeptides induced in murine macrophages a significant, but transient, increase of inositol 1,4,5-trisphosphate (IP3) levels at 60 seconds. On the contrary, these neuropeptides produced a rapid, transient and significant decrease of cAMP at 30 seconds. These results suggest that there are close relations between IP3 and cAMP messenger systems and the phagocytic process in murine peritoneal macrophages when these cells are incubated in the presence of bombesin, GRP or neuromedin C. PMID:1649124

  18. Citral and eugenol modulate DNA damage and pro-inflammatory mediator genes in murine peritoneal macrophages.

    PubMed

    Porto, Marilia de Paula; da Silva, Glenda Nicioli; Luperini, Bruno Cesar Ottoboni; Bachiega, Tatiana Fernanda; de Castro Marcondes, João Paulo; Sforcin, José Maurício; Salvadori, Daisy Maria Fávero

    2014-11-01

    Citral and eugenol have been broadly studied because of their anti-inflammatory, antioxidant and antiparasitic potentials. In this study, the effects of citral (25, 50 and 100 µg/mL) and eugenol (0.31, 0.62, 1.24 and 2.48 µg/mL) on the expression (RT-PCR) of the pro-inflammatory mediator genes NF-κB1, COX-2 and TNF-α were evaluated in mouse peritoneal macrophages with or without activation by a bacterial lipopolysaccharide (LPS). Additionally, the genotoxic potentials of two compounds and their capacities to modulate the DNA damage induced by doxorubicin (DXR) were investigated using the comet assay. The data revealed that neither citral nor eugenol changed COX-2, NF-κB1 or TNF-α expression in resting macrophages. However, in LPS-activated cells, citral induced the hypoexpression of COX-2 (100 µg/mL) and TNF-α (50 and 100 µg/mL). Hypoexpression of TNF-α was also detected after cellular exposure to eugenol at the highest concentration (2.48 µg/mL). Both compounds exhibited genotoxic potential (citral at 50 and 100 µg/mL and eugenol at all concentrations) but also showed chemopreventive effects, in various treatment protocols. Both citral and eugenol might modulate inflammatory processes and DXR-induced DNA damage, but the use of these compounds must be viewed with caution because they are also able to induce primary DNA lesions.

  19. Inhibitory effects of coumarin and acetylene constituents from the roots of Angelica furcijuga on D-galactosamine/lipopolysaccharide-induced liver injury in mice and on nitric oxide production in lipopolysaccharide-activated mouse peritoneal macrophages.

    PubMed

    Yoshikawa, Masayuki; Nishida, Norihisa; Ninomiya, Kiyofumi; Ohgushi, Teruki; Kubo, Mizuho; Morikawa, Toshio; Matsuda, Hisashi

    2006-01-15

    The methanolic extract (200 mg/kg, p.o. and i.p.), principal coumarin constituents (isoepoxypteryxin, anomalin, and praeroside IV), and a polyacetylene constituent (falcarindiol) (25 mg/kg, i.p.) from the roots of Angelica furcijuga protected the liver injury induced by D-galactosamine (D-GalN)/lipopolysaccharide (LPS) in mice. In in vitro experiments, coumarin constituents (hyuganins A-D, anomalin, pteryxin, isopteryxin, and suksdorfin) and polyacetylene constituents [(-)-falcarinol and falcarindiol] substantially inhibited LPS-induced NO and/or TNF-alpha production in mouse peritoneal macrophages, and isoepoxypteryxin inhibited D-GalN-induced cytotoxicity in primary cultured rat hepatocytes. Furthermore, hyuganin A, anomalin, and isopteryxin inhibited the decrease in cell viability by TNF-alpha in L929 cells.

  20. Peritonitis

    MedlinePlus

    Diseases and Conditions Peritonitis By Mayo Clinic Staff Peritonitis is inflammation of the peritoneum — a silk-like membrane that lines your inner abdominal ... usually due to a bacterial or fungal infection. Peritonitis can result from any rupture (perforation) in your ...

  1. Mycobacterium tuberculosis Prolyl Oligopeptidase Induces In vitro Secretion of Proinflammatory Cytokines by Peritoneal Macrophages

    PubMed Central

    Portugal, Brina; Motta, Flávia N.; Correa, Andre F.; Nolasco, Diego O.; de Almeida, Hugo; Magalhães, Kelly G.; Atta, Ana L. V.; Vieira, Francisco D.; Bastos, Izabela M. D.; Santana, Jaime M.

    2017-01-01

    Tuberculosis (TB) is a disease that leads to death over 1 million people per year worldwide and the biological mediators of this pathology are poorly established, preventing the implementation of effective therapies to improve outcomes in TB. Host–bacterium interaction is a key step to TB establishment and the proteases produced by these microorganisms seem to facilitate bacteria invasion, migration and host immune response evasion. We presented, for the first time, the identification, biochemical characterization, molecular dynamics (MDs) and immunomodulatory properties of a prolyl oligopeptidase (POP) from Mycobacterium tuberculosis (POPMt). POP is a serine protease that hydrolyzes substrates with high specificity for proline residues and has already been characterized as virulence factor in infectious diseases. POPMt reveals catalytic activity upon N-Suc-Gly-Pro-Leu-Gly-Pro-AMC, a recognized POP substrate, with optimal activity at pH 7.5 and 37°C. The enzyme presents KM and Kcat/KM values of 108 μM and 21.838 mM-1 s-1, respectively. MDs showed that POPMt structure is similar to that of others POPs, which consists of a cylindrical architecture divided into an α/β hydrolase catalytic domain and a β-propeller domain. Finally, POPMt was capable of triggering in vitro secretion of proinflammatory cytokines by peritoneal macrophages, an event dependent on POPMt intact structure. Our data suggests that POPMt may contribute to an inflammatory response during M. tuberculosis infection. PMID:28223969

  2. Modulation of functional characteristics of resident and thioglycollate-elicited peritoneal murine macrophages by a recombinant banana lectin.

    PubMed

    Marinkovic, Emilija; Djokic, Radmila; Lukic, Ivana; Filipovic, Ana; Inic-Kanada, Aleksandra; Kosanovic, Dejana; Gavrovic-Jankulovic, Marija; Stojanovic, Marijana

    2017-01-01

    We demonstrated that a recombinant banana lectin (rBanLec), which structural characteristics and physiological impacts highly resemble those reported for its natural counterparts, binds murine peritoneal macrophages and specifically modulates their functional characteristics. By using rBanLec in concentrations ranging from 1 μg to 10 μg to stimulate resident (RMs) and thioglycollate-elicited (TGMs) peritoneal macrophages from BALB/c and C57BL/6 mice, we have shown that effects of rBanLec stimulation depend on its concentration but also on the functional status of macrophages and their genetic background. rBanLec, in a positive dose-dependent manner, promotes the proliferation of TGMs from both BALB/c and C57BL/6 mice, while its mitogenic influence on RMs is significantly lower (BALB/c mice) or not detectable (C57BL/6 mice). In all peritoneal macrophages, irrespective of their type and genetic background, rBanLec, in a positive dose dependent manner, enhances the secretion of IL-10. rBanLec stimulation of RMs from both BALB/c and C57BL/6 resulted in a positive dose-dependent promotion of proinflammatory phenotype (enhancement of NO production and IL-12 and TNFα secretion, reduction of arginase activity). Positive dose-dependent skewing toward proinflammatory phenotype was also observed in TGMs from C57BL/6 mice. However, the enhancement of rBanLec stimulation promotes skewing of TGMs from BALB/c mice towards anti-inflammatory profile (reduction of NO production and IL-12 secretion, enhancement of arginase activity and TGFβ and IL-4 secretion). Moreover, we established that rBanLec binds oligosaccharide structures of TLR2 and CD14 and that blocking of signaling via these receptors significantly impairs the production of TNFα and NO in BALB/c macrophages. Since the outcome of rBanLec stimulation depends on rBanLec concentration as well as on the functional characteristics of its target cells and their genetic background, further studies are needed to investigate

  3. Modulation of functional characteristics of resident and thioglycollate-elicited peritoneal murine macrophages by a recombinant banana lectin

    PubMed Central

    Marinkovic, Emilija; Djokic, Radmila; Lukic, Ivana; Filipovic, Ana; Inic-Kanada, Aleksandra; Kosanovic, Dejana; Gavrovic-Jankulovic, Marija; Stojanovic, Marijana

    2017-01-01

    We demonstrated that a recombinant banana lectin (rBanLec), which structural characteristics and physiological impacts highly resemble those reported for its natural counterparts, binds murine peritoneal macrophages and specifically modulates their functional characteristics. By using rBanLec in concentrations ranging from 1 μg to 10 μg to stimulate resident (RMs) and thioglycollate-elicited (TGMs) peritoneal macrophages from BALB/c and C57BL/6 mice, we have shown that effects of rBanLec stimulation depend on its concentration but also on the functional status of macrophages and their genetic background. rBanLec, in a positive dose-dependent manner, promotes the proliferation of TGMs from both BALB/c and C57BL/6 mice, while its mitogenic influence on RMs is significantly lower (BALB/c mice) or not detectable (C57BL/6 mice). In all peritoneal macrophages, irrespective of their type and genetic background, rBanLec, in a positive dose dependent manner, enhances the secretion of IL-10. rBanLec stimulation of RMs from both BALB/c and C57BL/6 resulted in a positive dose-dependent promotion of proinflammatory phenotype (enhancement of NO production and IL-12 and TNFα secretion, reduction of arginase activity). Positive dose-dependent skewing toward proinflammatory phenotype was also observed in TGMs from C57BL/6 mice. However, the enhancement of rBanLec stimulation promotes skewing of TGMs from BALB/c mice towards anti-inflammatory profile (reduction of NO production and IL-12 secretion, enhancement of arginase activity and TGFβ and IL-4 secretion). Moreover, we established that rBanLec binds oligosaccharide structures of TLR2 and CD14 and that blocking of signaling via these receptors significantly impairs the production of TNFα and NO in BALB/c macrophages. Since the outcome of rBanLec stimulation depends on rBanLec concentration as well as on the functional characteristics of its target cells and their genetic background, further studies are needed to investigate

  4. Inhibition of mouse peritoneal macrophage DNA synthesis by infection with the Arenavirus Pichinde. Interim report

    SciTech Connect

    Friedlander, A.M.; Jahrling, P.B.; Merrill, P.; Tobery, S.

    1983-01-19

    Macrophage DNA synthesis and proliferation occur during the development of cell-mediated immunity and in the early non-specific reaction to infection. Arenaviruses have a predilection for infection of cells of the reticuloendothelial system and in this study we have examined the effect of the arenavirus Pichinde on macrophage DNA synthesis. We have found that infection of mouse peritoneal macrophages with Pichinde caused a profound dose dependent inhibition of the DNA synthesis induced by macrophage growth factor/colony stimulating factor. At a multiplicity of inoculum of five there is a 75-95% inhibition of DNA synthesis. Viable virus is necessary for inhibition since Pichinde inactivated by heat or cobalt irradiation had no effect. Similarly, virus pre-treated with an antiserum to Pichinde was without inhibitory effect. Inhibition was demonstrated by measuring DNA synthesis spectrofluorometrically as well as by 3H-thymidine incorporation. The inhibition of DNA synthesis was not associated with any cytopathology. There was no evidence that the inhibition was due to soluble factors, such as prostaglandins or interferon, released by infected cells. These studies demonstrate, for the first time in vitro, a significant alteration in macrophage function caused by infection with an arenavirus. It is possible that inhibition of macrophage proliferation represents a mechanism by which some microorganisms interfere with host resistance.

  5. In vivo killing and degradation of Mycobacterium aurum within mouse peritoneal macrophages.

    PubMed Central

    Silva, M T; Appelberg, R; Silva, M N; Macedo, P M

    1987-01-01

    We studied the in vivo killing and degradation of Mycobacterium aurum, a nonpathogenic, acid-fast bacillus, within macrophages after inoculation into the peritoneal cavity of CD-1 mice. The degradative process could be divided in five successive steps that were characterized on ultrastructural and cytochemical grounds and the relative contributions of which were determined by quantitative electron microscopy of samples taken at different times. The main ultrastructural alterations observed during the degradative process were ribosome disaggregation, coagulation of the cytoplasmic matrix, and change in the membrane profile from asymmetric to symmetric, with loss of the polysaccharide components from the outer layer, followed by membrane solubilization and intracellular clearing, followed by digestion of the innermost (peptidoglycan) layer of the cell wall, and at the end of the process, disorganization and collapse of the remaining layers of the cell wall. The correlation between viability and morphology indicated that the first ultrastructural signs of viability loss are cytoplasmic coagulation, change in the membrane geometry, and disappearance of ribosomes. The labeling of lysosomes of peritoneal macrophages with ferritin or by the cytochemical demonstration of inorganic trimetaphosphatase showed that fusion of lysosomes with phagosomes containing mycobacteria occurs in the phagocytes in the mouse peritoneal cavity and is already extensive as soon as 1 h after the inoculation of the bacilli. Images PMID:3623691

  6. Amphiregulin may be a new biomarker of classically activated macrophages.

    PubMed

    Meng, Chen; Liu, Guilin; Mu, Honglan; Zhou, Miaomiao; Zhang, Shihai; Xu, Younian

    2015-10-23

    Amphiregulin (Areg) participates in tissue repair and inflammation regulation. As important effector cells in inflammation, macrophages can be polarized to classically (M1) or alternatively (M2) activated phenotype with diverse functions in immunity. However, the relationship between Areg expression and macrophage activation is poorly understood. Here we report that Areg was significantly expressed in M1 but not in M2 macrophages. This was confirmed by analyses of RT-PCR and ELISA in peritoneal macrophages, and by evaluating protein expression in alveolar macrophages and RAW264.7 cells. Selective inhibitors of TLR4 (CLI-095) and MAP kinase, including Erk1/2 (PD98059), JNK (SP600125) and p38 (SB203580), significantly reduced Areg expression in M1 macrophages, suggesting that M1 macrophages produce Areg mainly through the TLR4-MAPK pathway, which is involved in the mechanism of M1 activation. When compared with productions of classical biomarkers of M1 macrophages, Areg expression was highly consistent in time series. Taken together, Areg may be an effective new biomarker of M1 macrophages.

  7. Capsaicin exhibits anti-inflammatory property by inhibiting IkB-a degradation in LPS-stimulated peritoneal macrophages.

    PubMed

    Kim, Chu-Sook; Kawada, Teruo; Kim, Byung-Sam; Han, In-Seob; Choe, Suck-Young; Kurata, Tadao; Yu, Rina

    2003-03-01

    Capsaicin, a major ingredient of hot pepper, was considered to exhibit an anti-inflammatory property. In order to clarify the signalling mechanism underlying the anti-inflammatory action of capsaicin, we investigated the effect of capsaicin on the production of inflammatory molecules in lipopolysaccharide (LPS)-stimulated murine peritoneal macrophages. The level of PGE2 was measured by EIA. The expression levels of COX-2, iNOS, IkB-a, and vanilloid receptor-1 (VR-1) were determined at the protein and mRNA levels. Significant inhibition of the production of LPS-induced PGE2 by capsaicin was observed in a dose-dependent manner. Capsaicin did not affect the COX-2 expression at either the protein or mRNA level, but inhibited the enzyme activity of COX-2 and the expression of the iNOS protein. Capsaicin completely blocked LPS-induced disappearance of IkB-a and therefore inactivated NF-kB. The inhibitory action of capsaicin on PGE2 production was not abolished by capsazepine, a specific antagonist to VR-1. A high expression level of the VR-1 like protein (VRL-1) was observed in peritoneal macrophages, while the expression of VR-1 was not detected. These findings suggest that the anti-inflammatory action of capsaicin may occur through a novel mechanism, not by a VR-1 receptor-mediated one. Both capsaicin and capsazepine may be a promising drug candidates for ameliorating inflammatory diseases and cancer.

  8. A defect in the inflammation-primed macrophage-activation cascade in osteopetrotic rats.

    PubMed

    Yamamoto, N; Lindsay, D D; Naraparaju, V R; Ireland, R A; Popoff, S N

    1994-05-15

    Macrophages were activated by administration of lysophosphatidylcholine (lyso-Pc) or dodecylglycerol (DDG) to wild-type rats but not in osteopetrotic (op) mutant rats. In vitro treatment of wild-type rat peritoneal cells with lyso-Pc or DDG efficiently activated macrophages whereas treatment of op mutant rat peritoneal cells with lyso-Pc or DDG did not activate macrophages. The inflammation-primed macrophage activation cascade in rats requires participation of B lymphocytes and vitamin D binding protein (DBP). Lyso-Pc-inducible beta-galactosidase of wild-type rat B lymphocytes can convert DBP to the macrophage-activating factor (MAF), whereas B lymphocytes of the op mutant rats were shown to be deficient in lyso-Pc-inducible beta-galactosidase. DBP is conserved among mammalian species. Treatment of human DBP (Gc1 protein) with commercial glycosidases yields an extremely high titrated MAF as assayed on mouse and rat macrophages. Because the enzymatically generated MAF (GcMAF) bypasses the role of lymphocytes in macrophage activation, the op mutant rat macrophages were efficiently activated by administration of a small quantity (100 pg/rat) of GcMAF. Likewise, in vitro treatment of op rat peritoneal cells with as little as 40 pg GcMAF/ml activated macrophages.

  9. Collagenase Production by Endotoxin-Activated Macrophages

    PubMed Central

    Wahl, Larry M.; Wahl, Sharon M.; Mergenhagen, Stephan E.; Martin, George R.

    1974-01-01

    Peritoneal exudate macrophages, when exposed to bacterial lipopolysaccharide in culture, were found to produce collagenase (EC 3.4.24.3). This enzyme was not detected in extracts of the macrophages or in media from nonstimulated macrophage cultures. Lipidcontaining fractions of the lipopolysaccharide, including a glycolipid from the rough mutant of Salmonella minnesota (R595) and lipid A, were potent stimulators of collagenase production. The lipid-free polysaccharide fraction had no effect. Cycloheximide prevented the production of collagenase by endotoxin-treated macrophages, suggesting that it was newly synthesized. Images PMID:4372628

  10. Methylglyoxal induced activation of murine peritoneal macrophages and surface markers of T lymphocytes in sarcoma-180 bearing mice: involvement of MAP kinase, NF-kappa beta signal transduction pathway.

    PubMed

    Pal, Aparajita; Bhattacharya, Iman; Bhattacharya, Kaushik; Mandal, Chitra; Ray, Manju

    2009-06-01

    Methylglyoxal profoundly stimulates host's immune response against tumor cell by producing reactive oxygen intermediates (ROI's) and reactive nitrogen intermediates (RNI's) [Bhattacharyya, N., Pal, A., Patra, S., Haldar, A.K., Roy, S., Ray, M., 2008. Activation of macrophages and lymphocytes by methylglyoxal against tumor cells in the host. Int. Immunophar. 8 (11), 1503-1512]. Present study indicated that methylglyoxal stimulates iNOS activation by p38 MAPK-NF-kappa beta dependent pathway and ROS production by ERK and JNK activation in sarcoma-180 tumor bearing mice. Proinflammatory cytokines, for macrophage activation, IL-6 and IL-1 beta were also increased. Production of TLR 4 and TLR 9, which acts through the same signaling pathway, were also upregulated. Hence, concluded that methylglyoxal augmented the IL-6 and IL-1 beta, expression of TLR 4 and TLR 9 and produced MAPKs, important regulators of ROIs and RNIs. Methylglyoxal treatment also increased M-CSF, an upregulator of macrophage production. CD8 and CD4 molecules, associated with T(C) and T(H) cells respectively, were also increased. Overall methylglyoxal treatment is important for enhancement of macrophages and lymphocyte activation or immunomodulation against sarcoma-180 tumor.

  11. In Vitro Response of Guinea Pig Peritoneal Macrophages to Legionella pneumophila

    DTIC Science & Technology

    1981-03-01

    causative agent of I strains. were cultured onl Mueller-Hinton agar supt)I- Legionnaires disease , have niot heeni well defined. niented with 2...In Vitro Responlse of Guinea Pig Peritoneal Macrophages to Legionella pneumophila It. A. KISIIIMi~O~’ .1. Ii.,W11ITE, F. G. SIREY, V. (U.1 Mc(GANN, R...obtained from the Centers for two washes of Hlanks balanced salt solution. Bacteria. Disease Control. Atlanta, Ga. The virulent P1hiladel- suspended in Earle

  12. Estradiol Is a Critical Mediator of Macrophage-Nerve Cross Talk in Peritoneal Endometriosis

    PubMed Central

    Greaves, Erin; Temp, Julia; Esnal-Zufiurre, Arantza; Mechsner, Sylvia; Horne, Andrew W.; Saunders, Philippa T.K.

    2016-01-01

    Endometriosis occurs in approximately 10% of women and is associated with persistent pelvic pain. It is defined by the presence of endometrial tissue (lesions) outside the uterus, most commonly on the peritoneum. Peripheral neuroinflammation, a process characterized by the infiltration of nerve fibers and macrophages into lesions, plays a pivotal role in endometriosis-associated pain. Our objective was to determine the role of estradiol (E2) in regulating the interaction between macrophages and nerves in peritoneal endometriosis. By using human tissues and a mouse model of endometriosis, we demonstrate that macrophages in lesions recovered from women and mice are immunopositive for estrogen receptor β, with up to 20% being estrogen receptor α positive. In mice, treatment with E2 increased the number of macrophages in lesions as well as concentrations of mRNAs encoded by Csf1, Nt3, and the tyrosine kinase neurotrophin receptor, TrkB. By using in vitro models, we determined that the treatment of rat dorsal root ganglia neurons with E2 increased mRNA concentrations of the chemokine C-C motif ligand 2 that stimulated migration of colony-stimulating factor 1–differentiated macrophages. Conversely, incubation of colony-stimulating factor 1 macrophages with E2 increased concentrations of brain-derived neurotrophic factor and neurotrophin 3, which stimulated neurite outgrowth from ganglia explants. In summary, we demonstrate a key role for E2 in stimulating macrophage-nerve interactions, providing novel evidence that endometriosis is an estrogen-dependent neuroinflammatory disorder. PMID:26073038

  13. Pulmonary Chlamydia muridarum challenge activates lung interstitial macrophages which correlate with IFN-γ production and infection control in mice.

    PubMed

    Gracey, Eric; Baglaenko, Yuriy; Prayitno, Nadia; Van Rooijen, Nico; Akram, Ali; Lin, Aifeng; Chiu, Basil; Inman, Robert D

    2015-12-01

    Protective immunity to the pathogen Chlamydia is dependent on a robust IFN-γ response generated by innate and adaptive lymphocytes. Here we assess the role of the macrophage in orchestrating a protective response in vivo to the murine pathogen, Chlamydia muridarum. During acute pulmonary and peritoneal infection, resident macrophages in both sites are infected with C. muridarum and adopt an inflammatory phenotype. In the lung, this activation is restricted to interstitial macrophages, which harbor higher levels of C. muridarum 16sRNA than alveolar macrophages. We examined innate and adaptive lymphocyte activation in the peritoneal cavity with macrophage depletion and with adoptive transfer of infected macrophages. These experiments demonstrate macrophage activation correlates with a protective IFN-γ response and effective control of C. muridarum. These studies suggest that a quantitative or qualitative alteration in macrophages may play a key role in the development of Chlamydia-associated diseases.

  14. Effects of lipopolysaccharide on the catabolic activity of macrophages

    SciTech Connect

    Cluff, C.; Ziegler, H.K.

    1986-03-05

    The ability of macrophages to degrade and catabolize antigens is of relevance both as a means to process complex antigens prior to presentation to T cells, as well as a way to down regulate immune responses by destroying the antigenicity of polypeptides. With these considerations, the authors have investigated the regulation of macrophage catabolic activity by lipopolysaccharide (LPS). Catabolic activity was quantitated by following the distribution and molecular form of /sup 125/-I labelled surface components of heat-killed Listeria monocytogenes (HKLM) subsequent to their uptake by macrophages. They have compared the catabolic activity of macrophages from peritoneal exudates of mice injected i.p. with saline or LPS and have found that LPS-elicited macrophages display a greatly enhanced (3 fold) rate of catabolism. This increase in catabolic activity peaks 3 days after LPS injection and steadily declines thereafter, approaching a baseline level after 3 weeks. The enhancement of catabolic activity is under LPS gene control. LPS-elicited macrophages rapidly destroy the antigenicity of bacterial antigens and function poorly as antigen presenting cells in vitro. These results suggest that LPS elicits a macrophage population specialized for antigen degradation functions with negative regulatory effects on the induction of specific immune responses.

  15. Low-dose cisplatin administration to septic mice improves bacterial clearance and programs peritoneal macrophage polarization to M1 phenotype.

    PubMed

    Li, Yanyan; Wang, Zhenling; Ma, Xuelei; Shao, Bin; Gao, Xiang; Zhang, Binglan; Xu, Guangchao; Wei, Yuquan

    2014-11-01

    Sepsis is a systemic inflammatory response to infection, and early responses of macrophages are vital in controlling the infected microorganisms. We used a cecal ligation and puncture (CLP) model of sepsis to determine the role of cisplatin (0.1, 0.5 and 1 mg kg(-1)) with respect to peritoneal macrophages, controlling peritoneal/blood bacterial infection, and systemic inflammation. We found that mice which received low-dose (0.1 and 0.5 mg kg(-1)) i.p. cisplatin had lower mortality rate and improved clinical scores compared with mice in normal saline-treated group, and the level of IL-6 and TNF-α was significantly reduced after cisplatin administration in peritoneal fluid of mice underwent CLP. Although cisplatin had no directly bactericidal ability, the numbers of bacteria in peritoneal and blood were significantly reduced at 24 and 72 h after the onset of CLP. Besides, in vivo phagocytosis and killing assay showed that the ability of macrophage derived from peritoneum was significantly increased with cisplatin treatment (5, 10, and 15 μM) for both gram-positive (Enterococcus faecalis) and gram-negative (Escherichia coli) bacteria. This was associated with the macrophage phenotype polarization from CD11b(+) F4/80(high) CD206(-) to CD11b(+) F4/80(low) CD206(-) M1 group. These findings underscore the importance of low-dose cisplatin in the treatment of sepsis.

  16. Culture of mouse peritoneal macrophages with mouse serum induces lipid bodies that associate with the parasitophorous vacuole and decrease their microbicidal capacity against Toxoplasma gondii

    PubMed Central

    Mota, Laura Azeredo Miranda; Roberto, João; Monteiro, Verônica Gomes; Lobato, Caroliny Samary Silva; de Oliveira, Marco Antonio; da Cunha, Maura; D’Ávila, Heloisa; Seabra, Sérgio Henrique; Bozza, Patrícia Torres; DaMatta, Renato Augusto

    2014-01-01

    Lipid bodies [lipid droplets (LBs)] are lipid-rich organelles involved in lipid metabolism, signalling and inflammation. Recent findings suggest a role for LBs in host response to infection; however, the potential functions of this organelle in Toxoplasma gondii infection and how it alters macrophage microbicidal capacity during infection are not well understood. Here, we investigated the role of host LBs in T. gondii infection in mouse peritoneal macrophages in vitro. Macrophages cultured with mouse serum (MS) had higher numbers of LBs than those cultured in foetal bovine serum and can function as a model to study the role of LBs during intracellular pathogen infection. LBs were found in association with the parasitophorous vacuole, suggesting that T. gondii may benefit from this lipid source. Moreover, increased numbers of macrophage LBs correlated with high prostaglandin E2 (PGE2) production and decreased nitric oxide (NO) synthesis. Accordingly, LB-enriched macrophages cultured with MS were less efficient at controlling T. gondii growth. Treatment of macrophages cultured with MS with indomethacin, an inhibitor of PGE2 production, increased the microbicidal capacity against T. gondii. Collectively, these results suggest that culture with MS caused a decrease in microbicidal activity of macrophages against T. gondii by increasing PGE2 while lowering NO production. PMID:25317704

  17. Expression of Nocardia brasiliensis superoxide dismutase during the early infection of murine peritoneal macrophages.

    PubMed

    Revol, Agnès; Espinoza-Ruiz, Marisol; Medina-Villanueva, Igor; Salinas-Carmona, Mario Cesar

    2006-12-01

    Nocardia brasiliensis is the main agent of actinomycetoma in Mexico, but little is known about its virulence and molecular pathogenic pathways. These facultative intracellular bacteria are able to survive and divide within the host phagocytic cells, in part by neutralizing the reactive oxygen intermediates. Superoxide dismutase (SOD) participates in the intracellular survival of several bacterial species and, in particular, constitutes one of Nocardia asteroides virulence factors. To clarify SOD participation in the N. brasiliensis early infective process, we report its isolation and the consequent comparison of its transcript level. A 630 bp polymerase chain reaction fragment that included most of the coding sequence of N. brasiliensis sodA was cloned. A competitive assay was developed, allowing comparison of bacterial sod expression in exponential culture and 1 h after infecting peritoneal macrophages from BALB/c mice. At that time, there were viable bacteria in the macrophages. The intracellular bacteria presented a clear decrease in their sod transcript amount, although their 16S rRNA (used as an internal control) and hsp levels were maintained or slightly increased, respectively. These results indicate that sodA transcription is not maintained within the SOS bacterial response induced by phagosomal conditions. Further kinetics will be necessary to precisely define sod transcriptional regulation during N. brasiliensis intra-macrophage growth.

  18. In vitro immune toxicity of polybrominated diphenyl ethers on murine peritoneal macrophages: apoptosis and immune cell dysfunction.

    PubMed

    Lv, Qi-Yan; Wan, Bin; Guo, Liang-Hong; Zhao, Lixia; Yang, Yu

    2015-02-01

    Polybrominated diphenyl ethers (PBDEs) are widely used as flame retardants and are often detected in the environment, wildlife, and humans, presenting potential threats to ecosystem and human health. PBDEs can cause neurotoxicity, hepatotoxicity, and endocrine disruption. However, data on PBDE immunotoxicity are limited, and the toxicity mechanisms remain largely unknown. Both immune cell death and dysfunction can modulate the responses of the immune system. This study examined the toxic effects of 2,2',4,4'-tetrabromodiphenyl ether (BDE-47) and decabromodiphenyl ether (BDE-209) on the immune system by using peritoneal macrophages as the model. The macrophages were exposed to PBDEs, and cell death was determined through flow cytometry and immunochemical blot. The results showed that after 24h of exposure, BDE-47 (>5 μM) and BDE-209 (>20 μM) induced cell apoptosis, increased intracellular reactive oxygen species (ROS) formation and depleted glutathione. BDE-47 was more potent than BDE-209; the cytotoxic concentrations for BDE-47 and BDE-209 were determined to be 5 μM and 20 μM, respectively, during 24h of exposure. However, pretreatment with n-acetyl-l-cysteine (ROS scavenger) partially reversed the cytotoxic effects. Further gene expression analyses on Caspase-3,-8,-9, TNFR1, and Bax revealed that both intrinsic and extrinsic apoptotic pathways were activated. More importantly, non-cytotoxic concentrations BDE-47 (<2 μM) and BDE-209 (<10 μM) could impair macrophage accessory cell function in a concentration-dependent manner, but no effects were observed on phagocytic responses. These revealed effects of PBDEs on macrophages may shed light on the toxicity mechanisms of PBDEs and suggest the necessity of evaluating cellular functionality during the risk assessment of PBDE immunotoxicity.

  19. Overload training inhibits phagocytosis and ROS generation of peritoneal macrophages: role of IGF-1 and MGF.

    PubMed

    Xiao, Weihua; Chen, Peijie; Wang, Ru; Dong, Jingmei

    2013-01-01

    We tested the hypothesis that overload training inhibits the phagocytosis and the reactive oxygen species (ROS) generation of peritoneal macrophages (Mϕs), and that insulin-like growth factor-1(IGF-1) and mechano-growth factor (MGF) produced by macrophages may contribute to this process. Rats were randomized to two groups, sedentary control group (n = 10) and overload training group (n = 10). The rats of overload training group were subjected to 11 weeks of experimental training protocol. Blood sample was used to determine the content of hemoglobin, testosterone, and corticosterone. The phagocytosis and the ROS generation of Mϕs were measured by the uptake of neutral red and the flow cytometry, respectively. IGF-1 and MGF mRNA levels in Mϕs were determined by real-time PCR. In addition, we evaluated the effects of IGF-1 and MGF peptide on phagocytosis and ROS generation of Mϕs in vitro. The data showed that overload training significantly decreased the body weight (19.3 %, P < 0.01), the hemoglobin (13.5 %, P < 0.01), the testosterone (55.3 %, P < 0.01) and the corticosterone (40.6 %, P < 0.01) in blood. Moreover, overload training significantly decreased the phagocytosis (27 %, P < 0.05) and the ROS generation (35 %, P < 0.01) of Mϕs. IGF-1 and MGF mRNA levels in Mϕs from overload training group increased significantly compared with the control group (21-fold and 92-fold, respectively; P < 0.01). In vitro experiments showed that IGF-1 had no significant effect on the phagocytosis and the ROS generation of Mϕs. Unlike IGF-1, MGF peptide impaired the phagocytosis of Mϕs in dose-independent manner. In addition, MGF peptide of some concentrations (i.e., 1, 10, 50, 100 ng/ml) significantly inhibited the ROS generation of Mϕs. These results suggest that overload training inhibits the phagocytosis and the ROS generation of peritoneal macrophages, and that MGF produced by macrophages may play a key role in this process. This may represent a novel mechanism of

  20. Peritoneal macrophages from patients with cirrhotic ascites show impaired phagocytosis and vigorous respiratory burst

    PubMed Central

    Ahmed, Abdel Motaal M.; Bomford, Adrian; Nouri-Aria, Kayhan T.; Davies, Ted; Smith, Roger; Williams, Roger

    2011-01-01

    Cirrhotic patients (CPs) are susceptible to spontaneous bacterial peritonitis (SBP). Aim of this study was to examine if this susceptibility was related to peritoneal macrophages' (PMs) altered host defence. Absorbance of phagocytosed particles by PMs from CPs was lower than that of control (31.88% vs. 77.2%). Particle opsonisation increased the absorbance to 41% in CPs' PMs, and this value remains lower than the control; 77.2%. Respiratory burst (RB) was expressed as fluorescence index values, and these were higher in PMs from CPs than in controls (82 vs. 41, 73 vs. 26 and 71 vs. 26). IFN-γ made no further increase of RB values in PMs from CPs. CD14 expression was also higher in CPs' PMs. IFN-γ significantly downregulated CD14 expression in both CPs' PMs and control. Reduced phagocytosis by predominantly CD14-positive PMs from CPs could be related to intense RB. Findings suggest altered host defence that could contribute to susceptibility to SBP. PMID:24371553

  1. Mitogen-activated protein kinase phosphatase-1 expression in macrophages is controlled by lymphocytes during macrophage activation.

    PubMed

    Luo, Chong; Yang, Xiqiang; Yao, Lan; Jiang, Liping; Liu, Wei; Li, Xin; Wang, Lijia

    2012-01-01

    The viewpoints on the control of innate immune cells by the adaptive immune system during sepsis remain controversial. Mitogen-activated protein kinase phosphatase-1 (MKP-1) is essential to the negative control of innate immunity and suppresses the activation of macrophages by inhibiting activated mitogen-activated protein kinase (MAPK). The purpose of the current study was to observe inflammatory response and macrophage activation in mice with severe combined immunodeficiency (SCID) with endotoxemia and to determine the role of MKP-1 in the control of macrophage activation by the adaptive immune system. Endotoxemia was induced in wild-type and SCID mice by an intraperitoneal injection of lipopolysaccharide (LPS), and all of the SCID mice died. SCID mice produced more inflammatory cytokines than BALB/c mice systemically and locally. TNF-α mRNA expression was higher and MKP-1 mRNA expression was lower in peritoneal macrophages (PMa) from SCID mice compared to PMa from wild-type mice after and even before LPS injection. Thioglycollate-stimulated PMa from wild-type mice were stimulated with LPS in vitro in the presence or absence of pan-T cells. The levels of TNF-α and IL-6 were higher in the supernatants from PMa cultured alone compared to PMa co-cultured with pan-T cells, and PMa MKP-1 mRNA and protein expression were higher when PMa were co-cultured with pan-T cells. Therefore, pan-T cells can up-regulate MKP-1 expression in macrophages and inhibit the secretion of inflammatory cytokines secretion by macrophages. In SCID mice, lymphocyte deficiency, especially T cell deficiency, causes insufficient MKP-1 expression in macrophages, which can be responsible for the severe inflammation and bad prognosis of septic SCID mice. MKP-1 plays an important role in the control of macrophage activation by the adaptive immune system.

  2. Isofraxidin exhibited anti-inflammatory effects in vivo and inhibited TNF-α production in LPS-induced mouse peritoneal macrophages in vitro via the MAPK pathway.

    PubMed

    Niu, Xiaofeng; Xing, Wei; Li, Weifeng; Fan, Ting; Hu, Hua; Li, Yongmei

    2012-10-01

    Isofraxidin (IF) is a Coumarin compound that can be isolated from medicinal plants, such as Sarcandra glabra (Thunb.). Nakai is widely used in Asian countries for the treatment of anti-bacterial, anti-inflammatory and anti-tumour action. The present investigation was designed to evaluate the effect of IF on inflammation and nociception. In addition, we investigated a potential novel mechanism to explain the anti-inflammatory properties of IF. In vivo, xylene-induced mouse ear edema, carrageenan-induced rat paw edema, LPS-induced mouse endotoxic shock, acetic acid-induced mice writhing and formalin-induced mouse pain models were used to evaluate the anti-inflammatory activity of IF. In vitro, we examined the effects of IF inhibition on TNF-α production and the regulation of ERK1/2 and p38 phosphorylation activity in LPS-induced mouse peritoneal macrophages. Our results demonstrated that IF can significantly decrease xylene-induced ear edema, carrageenan-induced paw edema, acetic acid-induced writhing and formalin-induced pain. Moreover, IF greatly inhibited the production of TNF-α in the serum of LPS-stimulated mice and peritoneal macrophages, and it decreased phospho-p38 and ERK1/2 protein expression in LPS-stimulated mouse peritoneal macrophages. Overall, our data suggest that IF possesses significant analgesic and anti-inflammatory activities that may be mediated through the regulation of pro-inflammatory cytokines, TNF-α and the phosphorylation of p38 and ERK1/2.

  3. Morinda citrifolia Linn. fruit (Noni) juice induces an increase in NO production and death of Leishmania amazonensis amastigotes in peritoneal macrophages from BALB/c.

    PubMed

    Almeida-Souza, Fernando; de Souza, Celeste da Silva Freitas; Taniwaki, Noemi Nosomi; Silva, João José Mendes; de Oliveira, Renata Mondêgo; Abreu-Silva, Ana Lúcia; Calabrese, Kátia da Silva

    2016-08-31

    Leishmaniasis is a complex disease that is considered a serious public health problem. Due to the absence of an effective vaccine and debilitating chemotherapy better therapies are urgently needed. This situation has stimulated the search for alternative treatments such as the use of herbal medicines. Several studies conducted with Morinda citrifolia Linn. have shown various biological activities such as antitumor, immunomodulation and antileishmanial activity, however its mechanisms of action are still unknown. This study aimed to analyze the activity of M. citrifolia fruit juice against Leishmania amazonensis and its action on peritoneal macrophages from BALB/c infected with L. amazonensis. Activity against the promastigote forms showed IC50 at 275.3 μg/mL. Transmission electron microscopy was used to evaluate the ultrastructural alterations in the promastigotes treated with the juice and the results showed cytoplasmic vacuolization, lipid inclusion and increased activity of exocytosis. The juice treatment presented an IC50 at 208.4 μg/mL against intracellular amastigotes and led to an increased nitrite production in infected and non-infected macrophages. When macrophages were pre-treated with iNOS inhibitors, aminoguanidine or 1400W, the intracellular amastigotes increased, demonstrating the important role of NO production in M. citrifolia fruit activity. In conclusion, our results reveal that treatment with M. citrifolia fruit juice can increase NO production in peritoneal macrophages and this ability has an important role in the killing of L. amazonensis intracellular amastigotes.

  4. Trypanosoma cruzi: the immunological induction of macrophage plasminogen activator requires thymus-derived lymphocytes

    PubMed Central

    1977-01-01

    In this article we describe methods in which unstimulated mouse peritoneal macrophages were induced to secrete high livels of plasminogen activator under in vitro conditions. The exposure of sensitized peritoneal or spleen cell populations from Trypanosoma cruzi- infected animals to either viable or heat-killed trypanosomes lead to the release of an inducing factor(s). Maximal levels of plasminogen activator secretion are achieved by the incubation of such factors (s) with unstimulated macrophages for 48 h. A significant increase in enzyme secretion was already observed after a 24 h incubation. The production of the inducing factor(s) by sensitized cells was immunologically specific and unrelated antigens did not stimulate the production of the factor(s) by sensitized peritoneal or spleen cell populations. The inducing factor(s) was produced by nylon-wool- fractionated spleen and peritoneal cells which had been depleted of marcrophages. Pretreatment of sensitized spleen cells with anti-theta serum and C abolished the production of the activating factor(s). The active supernatant fluids were able to induce secretion of macrophage plasminogen activator across H-2 barriers. Attempts to induce trypanocidal activity in unstimulated macrophages have not been successful. PMID:327013

  5. Phosphatidylserine receptor Tim-4 is essential for the maintenance of the homeostatic state of resident peritoneal macrophages.

    PubMed

    Wong, Kit; Valdez, Patricia A; Tan, Christine; Yeh, Sherry; Hongo, Jo-Anne; Ouyang, Wenjun

    2010-05-11

    Tim-4 is a phosphatidylserine (PS) receptor that is expressed on various macrophage subsets. It mediates phagocytosis of apoptotic cells by peritoneal macrophages. The in vivo functions of Tim-4 in phagocytosis and immune responses, however, are still unclear. In this study, we show that Tim-4 quickly forms punctate caps on contact with apoptotic cells, in contrast to its normal diffused expression on the surface of phagocytes. Despite its expression in marginal zone and tingible body macrophages, Tim-4 deficiency only minimally affects outcomes of several acute immune challenges, including the trapping of apoptotic cells in the marginal zone, the clearance apoptotic cells by tingible body macrophages, and the formation of germinal centers and elicitation of antibody responses against sheep red blood cells (SRBCs). In addition, Tim-4(-/-) resident peritoneal macrophages (rPMs) phagocytose necrotic cells and other opsonized targets normally. However, their ability to bind and engulf apoptotic cells is significantly compromised both in vitro and in vivo. Most importantly, Tim-4 deficiency results in increased cellularity in the peritoneum. Resting rPMs produce higher TNF-alpha in culture. Their response to LPS, on the contrary, is dampened. Our data support an indispensible role of Tim-4 in maintaining the homeostasis of rPMs.

  6. In vivo effect of fly ash on surface receptors of mice peritoneal macrophages

    SciTech Connect

    Dogra, S.; Khanna, A.K.; Kaw, J.L.

    1987-01-01

    Functional activity of macrophages was studied in mice up to 15 days after intraperitoneal injection of 2.5 and 5.0 mg of fly ash using in vitro parameters. Fly ash did not cause any variation in the type of cellular response. The total cell number decreased significantly by 4 days after fly ash treatment but recovered subsequently. The decrease was dose dependent. Fly ash also caused a 50% depression in the FC receptor mediated phagocytosis of IgG coated sheep erythrocytes (SRBC) by macrophages at 2 days of dust treatment. However, the recovery began earlier with 2.5 mg fly ash than with 5.0 mg fly ash. These changes were not associated with any marked changes in esterase activity of macrophages following phagocytosis of fly ash.

  7. Production of nitric oxide in mouse peritoneal macrophages after priming with interferon-gamma by the stem of Sinomenium acutum.

    PubMed

    Kim, H M; Oh, D I; Chung, C K

    1999-09-01

    The present study demonstrates that the aqueous extract of Sinomenium acutum stem (SSAE) produces nitric oxide (NO) upon treatment with recombinant interferon gamma (rIFN-gamma) in mouse peritoneal macrophages. Apparently SSAE has no effect on NO production by itself. This production is dependent on L-arginine and can be inhibited by the L-arginine analogue N(G)-monomethyl-L-arginine. The increased production of NO from rIFN-gamma plus SSAE-stimulated cells was decreased by the treatment of protein kinase C inhibitor. Tumor necrosis factor-alpha (TNF-alpha) has been shown to stimulate the oxidative metabolism of L-arginine to produce NO. Mouse peritoneal macrophages secrete high levels of TNF-alpha after incubation with rIFN-gamma plus SSAE. In addition, SSAE-induced NO production is progressively inhibited by anti-murine TNF-alpha neutralizing antibody. These results show that the capacity of SSAE to increase NO production from rIFN-gamma-primed mouse peritoneal macrophages is the result of SSAE-induced TNF-alpha secretion.

  8. Amelioration of oxidative DNA damage in mouse peritoneal macrophages by Hippophae salicifolia due to its proton (H+) donation capability: Ex vivo and in vivo studies

    PubMed Central

    Chakraborty, Mainak; Karmakar, Indrajit; Haldar, Sagnik; Das, Avratanu; Bala, Asis; Haldar, Pallab Kanti

    2016-01-01

    Introduction: The present study evaluates the antioxidant effect of methanol extract of Hippophae salicifolia (MEHS) bark with special emphasis on its role on oxidative DNA damage in mouse peritoneal macrophages. Material and Methods: In vitro antioxidant activity was estimated by standard antioxidant assays whereas the antioxidant activity concluded the H+ donating capacity. Mouse erythrocytes’ hemolysis and peritoneal macrophages’ DNA damage were determined spectrophotometrically. In vivo antioxidant activity of MEHS was determined in carbon tetrachloride-induced mice by studying its effect on superoxide anion production in macrophages cells, superoxide dismutase in the cell lysate, DNA damage, lipid peroxidation, and reduces glutathione. Results: The extract showed good in vitro antioxidant activities whereas the inhibitory concentrations values ranged from 5.80 to 106.5 μg/ml. MEHS significantly (P < 0.05) attenuated the oxidative DNA damage. It also attenuated the oxidative conversion of hemoglobin to methemoglobin and elevation of enzymatic and nonenzymatic antioxidant in cells. Conclusion: The result indicates MEHS has good in vitro-in vivo antioxidant property as well as the protective effect on DNA and red blood cell may be due to its H+ donating property. PMID:27413349

  9. TWEAK Promotes Peritoneal Inflammation

    PubMed Central

    Sanz, Ana Belen; Aroeira, Luiz Stark; Bellon, Teresa; del Peso, Gloria; Jimenez-Heffernan, Jose; Santamaria, Beatriz; Sanchez-Niño, Maria Dolores; Blanco-Colio, Luis Miguel; Lopez-Cabrera, Manuel; Ruiz-Ortega, Marta; Egido, Jesus; Selgas, Rafael; Ortiz, Alberto

    2014-01-01

    Peritoneal dialysis (PD) is complicated by peritonitis episodes that cause loss of mesothelium and eventually sclerosing peritonitis. An improved understanding of the molecular contributors to peritoneal injury and defense may increase the therapeutic armamentarium to optimize peritoneal defenses while minimizing peritoneal injury. There is no information on the expression and function of the cytokine TWEAK and its receptor Fn14 during peritoneal injury. Fn14 expression and soluble TWEAK levels were measured in human PD peritoneal effluent cells or fluids with or without peritonitis. Fn14 expression was also analyzed in peritoneal biopsies from PD patients. Actions of intraperitoneal TWEAK were studied in mice in vivo. sTWEAK levels were increased in peritoneal effluent in PD peritonitis. Effluent sTWEAK levels correlated with the number of peritoneal macrophages (r = 0.491, p = 0.002). Potential TWEAK targets that express the receptor Fn14 include mesothelial cells and macrophages, as demonstrated by flow cytometry of peritoneal effluents and by analysis of peritoneal biopsies. Peritoneal biopsy Fn14 correlated with mesothelial injury, fibrosis and inflammation, suggesting a potential deleterious effect of TWEAK/Fn14. In this regard, intraperitoneal TWEAK administration to mice promoted peritoneal inflammation characterized by increased peritoneal effluent MCP-1, Fn14 and Gr1+ macrophages, increased mesothelial Fn14, MCP-1 and CCL21 expression and submesothelial tissue macrophage recruitment. Taken together these data suggest that the TWEAK/Fn14 system may promote inflammation and tissue injury during peritonitis and PD. PMID:24599047

  10. LPS-inducible factor(s) from activated macrophages mediates cytolysis of Naegleria fowleri amoebae

    SciTech Connect

    Cleary, S.F.; Marciano-Cabral, F.

    1986-03-01

    Soluble cytolytic factors of macrophage origin have previously been described with respect to their tumoricidal activity. The purpose of this study was to investigate the mechanism and possible factor(s) responsible for cytolysis of the amoeba Naegleria fowleri by activated peritoneal macrophages from B6C3F1 mice. Macrophages or conditioned medium (CM) from macrophage cultures were incubated with /sup 3/H-Uridine labeled amoebae. Percent specific release of label served as an index of cytolysis. Bacille Calmette-Guerin (BCG) and Corynebacterium parvum macrophages demonstrated significant cytolysis of amoebae at 24 h with an effector to target ratio of 10:1. Treatment of macrophages with inhibitors of RNA or protein synthesis blocked amoebicidal activity. Interposition of a 1 ..mu..m pore membrane between macrophages and amoebae inhibited killing. Inhibition in the presence of the membrane was overcome by stimulating the macrophages with LPS. CM from SPS-stimulated, but not unstimulated, cultures of activated macrophages was cytotoxic for amoebae. The activity was heat sensitive and was recovered from ammonium sulfate precipitation of the CM. Results indicate that amoebicidal activity is mediated by a protein(s) of macrophage origin induced by target cell contact or stimulation with LPS.

  11. Modulatory effect of plumbagin (5-hydroxy-2-methyl-1,4-naphthoquinone) on macrophage functions in BALB/c mice. I. Potentiation of macrophage bactericidal activity.

    PubMed

    Abdul, K M; Ramchender, R P

    1995-09-01

    The modulatory ability of plumbagin, a natural product from Plumbago zeylanica, was studied on peritoneal macrophages of BALB/c mice. The macrophage functions evaluated were bactericidal activity, hydrogen peroxide and superoxide anion release. The bactericidal capacity of in vivo plumbagin-treated mouse macrophages was estimated against Staphylococcus aureus. In low doses plumbagin exerted a constant increase in bactericidal activity throughout the study period whereas with a high dose a higher response was observed up to six weeks. But in the next two weeks a considerable decline in the bactericidal activity was noticed compared to low dose. Plumbagin was also seen to exert a similar response on oxygen radical release by macrophages in vivo showing a clear correlation between oxygen radical release and the bactericidal activity. The data indicate that plumbagin augments the macrophage bactericidal activity by potentiating the oxyradical release at low concentration whereas at the higher concentration it has inhibitory activity.

  12. Role of prostaglandin E2 in peptidoglycan mediated iNOS expression in mouse peritoneal macrophages in vitro.

    PubMed

    Dahiya, Yogesh; Pandey, Rajeev Kumar; Bhatt, Kunal H; Sodhi, Ajit

    2010-10-08

    Many extracellular stimuli, e.g. microbial products, cytokines etc., result in the expression of inducible nitric oxide synthase (iNOS) in macrophages. However, it is not known whether expression of the iNOS gene in response to microbial products is a primary response of macrophages, or is the result of paracrine/autocrine signalling induced by endogenous biomolecules that are synthesised as a result of host cell-microbe interaction. In this paper we demonstrate that iNOS expression in mouse peritoneal macrophages in response to bacterial peptidoglycan (PGN) is a secondary effect requiring autocrine signalling of endogenously produced prostaglandin E2, and that PGN stimulation is mandatory, but not sufficient in itself, for induction of iNOS expression.

  13. MicroRNA-223 Induced Repolarization of Peritoneal Macrophages Using CD44 Targeting Hyaluronic Acid Nanoparticles for Anti-Inflammatory Effects

    PubMed Central

    Tran, Thanh-Huyen; Krishnan, Swathi; Amiji, Mansoor M.

    2016-01-01

    The aim of this study was to evaluate macrophages repolarization from pro-inflammatory M1 to anti-inflammatory M2 phenotype upon transfection with microRNA-223 (miR-223) duplexes and miR-223 expressing plasmid DNA encapsulated in CD44-targeting hyaluronic acid-poly(ethyleneimine) (HA-PEI) nanoparticles (NPs). The HA-PEI/miR-223 NPs with spherical shape and an average diameter of 200 nm were efficiently internalized by J774A.1 alveolar and primary peritoneal macrophages and non-cytotoxic at HA-PEI concentration less than 200 μg/mL. Transfection of HA-PEI/miR-223 NPs in J774A.1 macrophages showed significantly higher miR-223 expression than that with HA-PEI/plasmid DNA expressing miR-223 (pDNA-miR-223). HA-PEI/miR-223 NPs mediated transfection increased miR-223 expression to 90 fold in primary peritoneal macrophages compared to untreated cells. The overexpression of miR-223 in both J774A.1 and peritoneal macrophages induced a phenotypic change from M1 to M2 state as indicated by a decrease in iNOS-2 (M1 marker) and an increase in Arg-1 (M2 marker) levels compared to those in lipopolysaccharide (LPS) and interferon-gamma (IFN-γ)-stimulated macrophages (M1). The change in macrophage phenotype by HA-PEI/miR-223 NPs could suppress the inflammation in peritoneal macrophages induced by LPS as evidenced by a significant decrease in pro-inflammatory cytokine levels TNF-α, IL-1β and IL-6, compared to LPS-stimulated peritoneal macrophages without treatment. The results demonstrated that miR-223-encapsulated HA-PEI NPs modulated macrophage polarity toward an anti-inflammatory M2 phenotype, which has potential for the treatment of inflammatory diseases. PMID:27148749

  14. Reduced secretion of the inflammatory cytokine IL-1β by stimulated peritoneal macrophages of radiosensitive Balb/c mice after exposure to 0.5 or 0.7 Gy of ionizing radiation.

    PubMed

    Frischholz, Birgit; Wunderlich, Roland; Rühle, Paul-Friedrich; Schorn, Christine; Rödel, Franz; Keilholz, Ludwig; Fietkau, Rainer; Gaipl, Udo S; Frey, Benjamin

    2013-08-01

    Since the beginning of the 20th century, low dose radiotherapy (LD-RT) has been practiced and established as therapy of inflammatory diseases. Several clinical studies already have proven the anti-inflammatory effect of low doses of ionizing irradiation (LDR). However, further research is inevitable to reveal the underlying immune-biological mechanisms. Focus has been set on the modulation of activated macrophages by LDR, since they participate in both, initiation and resolution of inflammation. Here we examined with an ex vivo peritoneal mouse macrophage model how LDR modulates the secretion of the inflammatory cytokines IL-1β and TNF-α by activated macrophages and whether the basal radiosensitivity of the immune cells has influence on it. Peritoneal macrophages of Balb/c mice responded to exposure of 0.5 or 0.7 Gy of ionizing irradiation (X-ray) with significant decreased release of IL-1β and slightly, but not significantly, reduced release of TNF-α. Macrophages of the less radiosensitive C57BL/6 mice did not show this anti-inflammatory reaction. This was observed in both wild type and human TNF-α transgenic animals with C57BL/6 background. We conclude that only the inflammatory phenotype of more radiosensitive macrophages is reduced by LDR and that ex vivo and in vivo models with primary cells should be applied to examine how the immune system is modulated by LDR.

  15. Piroxicam, indomethacin and aspirin action on a murine fibrosarcoma. Effects on tumour-associated and peritoneal macrophages.

    PubMed Central

    Valdéz, J C; Perdigón, G

    1991-01-01

    Growth of a methylcholanthrene-induced fibrosarcoma in BALB/c mice was accompanied by an increase in the activation state of tumour-associated macrophages (TAM), as measured by their FcIgG receptor expression, phagocytic index and beta-glucuronidase levels. All of these parameters were markedly higher in TAM than in peritoneal macrophages (PM) derived from the same animal. On the other hand, PM from tumour-bearing mice showed lower activation parameters than PM from normal animals. We also studied the effect on tumour development of three inhibitors of prostaglandin synthesis: indomethacin, piroxicam and aspirin. Intraperitoneal administration of these drugs during 8 d was followed by the regression of palpable tumours. Indomethacin (90 mg/d) induced 45% regression, while with piroxicam (two 400 mg/d doses and six 200 mg/d doses) and aspirin (1 mg/d) 32% and 30% regressions, respectively, were observed. The growth rate of nonregressing tumours, which had reached different volumes by the end of the treatment, was delayed to a similar extent by the three anti-inflammatory non-steroidal drugs (NSAID). With respect to TAM, the treatment did not induce any significant change in their activation state, though both piroxicam and indomethacin increased slightly the TAM number. In contrast, NSAID administration was followed by a remarkable increase in the activation parameters of PM when compared with PM from tumour-bearing mice receiving no treatment. Indeed, these parameters were in some cases higher than those of PM from normal mice. The leukocytosis (60,000/microliters) with neutrophilia (80%) induced by tumour growth on peripheral blood leukocytes (PBL) was reversed by the treatment to values close to normal, in parallel with the reduction of tumour size. A drop in haematocrit was also noted which was most probably a consequence of tumour growth rather than of the treatment. This study reveals that the three NSAID tested have a remarkable antitumour activity, which

  16. Berberine augments ATP-induced inflammasome activation in macrophages by enhancing AMPK signaling

    PubMed Central

    Xu, Li-Hui; Liang, Yi-Dan; Wei, Hong-Xia; Hu, Bo; Pan, Hao; Zha, Qing-Bing; Ouyang, Dong-Yun; He, Xian-Hui

    2017-01-01

    The isoquinoline alkaloid berberine possesses many pharmacological activities including antibacterial infection. Although the direct bactericidal effect of berberine has been documented, its influence on the antibacterial functions of macrophages is largely unknown. As inflammasome activation in macrophages is important for the defense against bacterial infection, we aimed to investigate the influence of berberine on inflammasome activation in murine macrophages. Our results showed that berberine significantly increased ATP-induced inflammasome activation as reflected by enhanced pyroptosis as well as increased release of caspase-1p10 and mature interleukin-1β (IL-1β) in macrophages. Such effects of berberine could be suppressed by AMP-activated protein kinase (AMPK) inhibitor compound C or by knockdown of AMPKα expression, indicating the involvement of AMPK signaling in this process. In line with increased IL-1β release, the ability of macrophages to kill engulfed bacteria was also intensified by berberine. This was corroborated by the in vivo finding that the peritoneal live bacterial load was decreased by berberine treatment. Moreover, berberine administration significantly improved survival of bacterial infected mice, concomitant with increased IL-1β levels and elevated neutrophil recruitment in the peritoneal cavity. Collectively, these data suggested that berberine could enhance bacterial killing by augmenting inflammasome activation in macrophages through AMPK signaling. PMID:27980220

  17. Non-specific recognition in phagocytosis: ingestion of aldehyde-treated erythrocytes by rat peritoneal macrophages.

    PubMed Central

    Capo, C; Bongrand, P; Benoliel, A M; Depieds, R

    1979-01-01

    Particles were chemically modified with aldehydes and incubated with rat peritoneal cells for phagocytosis. All dialdehydes and lower monaldehydes tested (methanal, ethanal and propanal) made sheep erythrocytes phagocytosable. Failure of higher monaldehydes to induce phagocytosis of treated erythrocytes was not due to lack of reactivity with red cell membranes. All erythrocytes tested (bird and mammal red cells were used) and rat thymocytes were phagocytosed by rat macrophages after incubation with aldehyde. Treatment of Candida albicans did not induce phagocytosis: this failure was not due to lack of aldehyde binding (as demonstrated with [14C]-methanal) nor to anti-phagocytic properties of the parasite membrane. Sheep erythrocytes were submitted to enzymatic treatment (pronase, trypsin, neuraminidase) or incubated with succinic anhydride (to block free NH2 groups) or iodacetamide (to block free SH groups) before aldehyde treatment: phagocytosis was not decreased, which suggested that aldehydes did not act by altering some definite surface structure of the treated particles. Treatment of erythrocytes with cross-linking compounds such as tetraazotized o-dianisidine (coupling occurs mainly on tyrosine and histidine residues) or l-ethyl(3-dimethyl aminopropyl) carbodiimide (a bivalent reagent binding free COOH groups) did not induce any substantial phagocytosis of erythrocytes. Phagocytosis of aldehyde treated erythrocytes was partly correlated with hydrophobicity of these cells, as measured with a two-phase partition system. It is concluded that aldehyde-mediated phagocytosis of erythrocytes is mainly due to cross-linking of red cell membrane structures, probably involving free OH groups, which must increase local rigidity and thereby modify hydrophobicity of the red cell surface. Images Figure 1 PMID:437841

  18. Non-specific recognition in phagocytosis: ingestion of aldehyde-treated erythrocytes by rat peritoneal macrophages.

    PubMed

    Capo, C; Bongrand, P; Benoliel, A M; Depieds, R

    1979-03-01

    Particles were chemically modified with aldehydes and incubated with rat peritoneal cells for phagocytosis. All dialdehydes and lower monaldehydes tested (methanal, ethanal and propanal) made sheep erythrocytes phagocytosable. Failure of higher monaldehydes to induce phagocytosis of treated erythrocytes was not due to lack of reactivity with red cell membranes. All erythrocytes tested (bird and mammal red cells were used) and rat thymocytes were phagocytosed by rat macrophages after incubation with aldehyde. Treatment of Candida albicans did not induce phagocytosis: this failure was not due to lack of aldehyde binding (as demonstrated with [14C]-methanal) nor to anti-phagocytic properties of the parasite membrane. Sheep erythrocytes were submitted to enzymatic treatment (pronase, trypsin, neuraminidase) or incubated with succinic anhydride (to block free NH2 groups) or iodacetamide (to block free SH groups) before aldehyde treatment: phagocytosis was not decreased, which suggested that aldehydes did not act by altering some definite surface structure of the treated particles. Treatment of erythrocytes with cross-linking compounds such as tetraazotized o-dianisidine (coupling occurs mainly on tyrosine and histidine residues) or l-ethyl(3-dimethyl aminopropyl) carbodiimide (a bivalent reagent binding free COOH groups) did not induce any substantial phagocytosis of erythrocytes. Phagocytosis of aldehyde treated erythrocytes was partly correlated with hydrophobicity of these cells, as measured with a two-phase partition system. It is concluded that aldehyde-mediated phagocytosis of erythrocytes is mainly due to cross-linking of red cell membrane structures, probably involving free OH groups, which must increase local rigidity and thereby modify hydrophobicity of the red cell surface.

  19. Targeting colon cancer cell NF-κB promotes an anti-tumour M1-like macrophage phenotype and inhibits peritoneal metastasis.

    PubMed

    Ryan, A E; Colleran, A; O'Gorman, A; O'Flynn, L; Pindjacova, J; Lohan, P; O'Malley, G; Nosov, M; Mureau, C; Egan, L J

    2015-03-19

    In a model of peritoneal metastasis in immune-competent mice, we show that nuclear factor (NF)-κB inhibition in CT26 colon cancer cells prevents metastasis. NF-κB inhibition, by stable overexpression of IκB-α super-repressor, induced differential polarization of co-cultured macrophages to an M1-like anti-tumour phenotype in vitro. NF-κB-deficient cancer cell-conditioned media (CT26/IκB-α SR) induced interleukin (IL)-12 and nitric oxide (NO) synthase (inducible NO synthase (iNOS)) expression in macrophages. Control cell (CT26/EV) conditioned media induced high levels of IL-10 and arginase in macrophages. In vivo, this effect translated to reduction in metastasis in mice injected with CT26/ IκB-α SR cells and was positively associated with increased CD8(+)CD44(+)CD62L(-) and CD4(+)CD44(+)CD62L(-) effector T cells. Furthermore, inhibition of NF-κB activity induced high levels of NO in infiltrating immune cells and decreases in matrix metalloproteinase-9 expression, simultaneous with increases in tissue inhibitor of metalloproteinases 1 and 2 within tumours. CT26/IκB-α SR tumours displayed increased pro-inflammatory gene expression, low levels of angiogenesis and extensive intratumoral apoptosis, consistent with the presence of an anti-tumour macrophage phenotype. Macrophage depletion reduced tumour size in CT26/EV-injected animals and increased tumour size in CT26/IκB-α SR cells compared with untreated tumours. Our data demonstrate, for the first time, that an important implication of targeting tumour cell NF-κB is skewing of macrophage polarization to an anti-tumour phenotype. This knowledge offers novel therapeutic opportunities for anticancer treatment.

  20. Effects of Omega-3-Rich Harp Seal Oil on the Production of Pro-Inflammatory Cytokines in Mouse Peritoneal Macrophages.

    PubMed

    Choi, Myungwon; Ju, Jaehyun; Suh, Jae Soo; Park, Kun-Young; Kim, Kwang Hyuk

    2015-06-01

    Omega-3, a polyunsaturated fatty acid, is an essential fatty acid necessary for human health, and it protects against cardiovascular disease, inflammation, autoimmune diseases, and cancer. In the present study, we investigated the effects of omega-3-rich harp seal oil (HSO) on the production of nitric oxide (NO) and cytokines, such as tumor necrosis factor (TNF)-α, interleukin-(IL)-1β, IL-6, and IL-12/IL-23 (p40) in peritoneal macrophages of mice. The culture supernatants of murine macrophages exposed to lipopolysaccharide (LPS), HSO, or HSO+LPS were harvested to assay IL-1β, TNF-α, IL-6, and IL-12/IL-23 (p40) cytokines and NO. TNF-α, IL-1 β, and IL-12/IL-23 (p40) levels, except IL-6, were lower in the culture supernatants of mouse peritoneal macrophages exposed to LPS plus HSO than those of the groups exposed to LPS alone. These observations demonstrate that omega-3-rich harp seal oil downregulates the production of the pro-inflammatory cytokines such as IL-1β, TNF-α, and IL-12/IL-23 (p40). These results suggest that HSO could be potentially used as a preventive agent or as an adjunct in anti-inflammatory therapy, if more research results were accumulated.

  1. Effects of Omega-3-Rich Harp Seal Oil on the Production of Pro-Inflammatory Cytokines in Mouse Peritoneal Macrophages

    PubMed Central

    Choi, Myungwon; Ju, Jaehyun; Suh, Jae Soo; Park, Kun-Young; Kim, Kwang Hyuk

    2015-01-01

    Omega-3, a polyunsaturated fatty acid, is an essential fatty acid necessary for human health, and it protects against cardiovascular disease, inflammation, autoimmune diseases, and cancer. In the present study, we investigated the effects of omega-3-rich harp seal oil (HSO) on the production of nitric oxide (NO) and cytokines, such as tumor necrosis factor (TNF)-α, interleukin-(IL)-1β, IL-6, and IL-12/IL-23 (p40) in peritoneal macrophages of mice. The culture supernatants of murine macrophages exposed to lipopolysaccharide (LPS), HSO, or HSO+LPS were harvested to assay IL-1β, TNF-α, IL-6, and IL-12/IL-23 (p40) cytokines and NO. TNF-α, IL-1 β, and IL-12/IL-23 (p40) levels, except IL-6, were lower in the culture supernatants of mouse peritoneal macrophages exposed to LPS plus HSO than those of the groups exposed to LPS alone. These observations demonstrate that omega-3-rich harp seal oil downregulates the production of the pro-inflammatory cytokines such as IL-1β, TNF-α, and IL-12/IL-23 (p40). These results suggest that HSO could be potentially used as a preventive agent or as an adjunct in anti-inflammatory therapy, if more research results were accumulated. PMID:26175994

  2. Receptor-recognized alpha 2-macroglobulin-methylamine elevates intracellular calcium, inositol phosphates and cyclic AMP in murine peritoneal macrophages.

    PubMed Central

    Misra, U K; Chu, C T; Rubenstein, D S; Gawdi, G; Pizzo, S V

    1993-01-01

    Human plasma alpha 2-macroglobulin (alpha 2M) is a tetrameric proteinase inhibitor, which undergoes a conformational change upon reaction with either a proteinase or methylamine. As a result, a receptor recognition site is exposed on each subunit of the molecule enabling it to bind to its receptors on macrophages. We have used Fura-2-loaded murine peritoneal macrophages and digital video fluorescence microscopy to examine the effects of receptor binding on second messenger levels. alpha 2M-methylamine caused a rapid 2-4-fold increase in intracellular Ca2+ concentration ([Ca2+]i) within 5 s of binding to receptors. The agonists induced a focal increase in [Ca2+]i that spread out to other areas of the cell. The increase in [Ca2+]i was dependent on the alpha 2M-methylamine concentration and on the extracellular [Ca2+]. Both sinusoidal and transitory oscillations were observed, which varied from cell to cell. Neither alpha 2M nor boiled alpha 2M-methylamine, forms that are not recognized by the receptor, affected [Ca2+]i in peritoneal macrophages under identical conditions of incubation. The alpha 2M-methylamine-induced rise in [Ca2+]i was accompanied by a rapid and transient increase in macrophage inositol phosphates, including inositol tris- and tetrakis-phosphates. Native alpha 2M did not stimulate a rise in inositol phosphates. Finally, binding of alpha 2M-methylamine to macrophages increased cyclic AMP transiently. Thus receptor-recognized alpha-macroglobulins behave as agonists whose receptor binding causes stimulation of signal transduction pathways. Images Figure 2 PMID:7681282

  3. Transplantable Subcutaneous Hepatoma 22a Affects Functional Activity of Resident Tissue Macrophages in Periphery

    PubMed Central

    Kisseleva, Ekaterina P.; Krylov, Andrei V.; Stepanova, Olga I.; Lioudyno, Victoria I.

    2011-01-01

    Tumors spontaneously develop central necroses due to inadequate blood supply. Recent data indicate that dead cells and their products are immunogenic to the host. We hypothesized that macrophage tumor-dependent reactions can be mediated differentially by factors released from live or dead tumor cells. In this study, functional activity of resident peritoneal macrophages was investigated in parallel with tumor morphology during the growth of syngeneic nonimmunogenic hepatoma 22a. Morphometrical analysis of tumor necroses, mitoses and leukocyte infiltration was performed in histological sections. We found that inflammatory potential of peritoneal macrophages in tumor-bearing mice significantly varied depending on the stage of tumor growth and exhibited two peaks of activation as assessed by nitroxide and superoxide anion production, 5′-nucleotidase activity and pinocytosis. Increased inflammatory reactions were not followed by the enhancement of angiogenic potential as assessed by Vascular Endothelial Growth Factor mRNA expression. Phases of macrophage activity corresponded to the stages of tumor growth characterized by high proliferative potential. The appearance and further development of necrotic tissue inside the tumor did not coincide with changes in macrophage behavior and therefore indirectly indicated that activation of macrophages was a reaction mostly to the signals produced by live tumor cells. PMID:21760797

  4. The insect peptide CopA3 inhibits lipopolysaccharide-induced macrophage activation.

    PubMed

    Nam, Hyo Jung; Oh, Ah Reum; Nam, Seung Taek; Kang, Jin Ku; Chang, Jong Soo; Kim, Dae Hong; Lee, Ji Hye; Hwang, Jae Sam; Shong, Ko Eun; Park, Mi Jung; Seok, Heon; Kim, Ho

    2012-10-01

    We recently demonstrated that the insect peptide CopA3 (LLCIALRKK), a disulfide-linked dimeric peptide, exerts antimicrobial and anti-inflammatory activities in a mouse colitis model. Here, we examined whether CopA3 inhibited activation of macrophages by LPS. Exposure of an unseparated mouse peritoneal cell population or isolated peritoneal macrophages to LPS markedly increased secretion of IL-6 and TNF-α; these effects were significantly inhibited by CopA3 treatment. The inhibitory effect of CopA3 was also evident in murine macrophage cell line, RAW 264.7. Western blotting revealed that LPS-induced activation of STAT1 and STAT5 in macrophages was significantly inhibited by CopA3. Inhibition of JAK (STAT1/STAT5 kinase) with AG490 markedly reduced the production of IL-6 and TNF-α in macrophages. Collectively, these observations suggest that CopA3 inhibits macrophage activation by inhibiting activating phosphorylations of the transcription factors, STAT1 and STAT5, and blocking subsequent production of IL-6 and TNF-α and indicate that CopA3 may be useful as an immune-modulating agent.

  5. Comparative study of peritoneal macrophage functions in mice receiving lethal and non-lethal doses of LPS.

    PubMed

    Víctor, V M; De la Fuente, M

    2000-01-01

    In previous studies, we have observed changes in several functions of peritoneal macrophages from female BALB/c mice with lethal endotoxic shock caused by intraperitoneal injection of Escherichia coli O55:B5 lipopolysaccharide (LPS; 100 mg/kg), which were associated with a high production of superoxide anion and tumor necrosis factor alpha (TNF-alpha). In the present work, both a lethal dose (250 mg/kg) and a non-lethal dose (100 mg/kg) of LPS were used in female Swiss mice. In peritoneal macrophages, the following functions were studied at 2, 4, 12 and 24 h after LPS injection: adherence to substrate, chemotaxis, ingestion of particles, and superoxide anion and TNF-alpha production. In both groups, the results showed a stimulation of adherence, ingestion and superoxide production as well as a decrease of chemotaxis, whereas TNF-alpha could not be detected in either of the two groups. These effects were more evident with the 250 mg/kg dose, especially as regards superoxide anion production, which was higher in the animals treated with a lethal dose of LPS.

  6. Th1 CD4+ lymphocytes delete activated macrophages through the Fas/APO-1 antigen pathway.

    PubMed Central

    Ashany, D; Song, X; Lacy, E; Nikolic-Zugic, J; Friedman, S M; Elkon, K B

    1995-01-01

    The Fas/APO-1 cytotoxic pathway plays an important role in the regulation of peripheral immunity. Recent evidence indicates that this regulatory function operates through deletion of activated T and B lymphocytes by CD4+ T cells expressing the Fas ligand. Because macrophages play a key role in peripheral immunity, we asked whether Fas was involved in T-cell-macrophage interactions. Two-color flow cytometry revealed that Fas receptor (FasR) was expressed on resting murine peritoneal macrophages. FasR expression was upregulated after activation of macrophages with cytokines or lipopolysaccharide, although only tumor necrosis factor-alpha rendered macrophages sensitive to anti-FasR antibody-mediated death. To determine the consequence of antigen presentation by macrophages to CD4+ T cells, macrophages were pulsed with antigen and then incubated with either Th1 or Th2 cell lines or clones. Th1, but not Th2, T cells induced lysis of 60-80% of normal macrophages, whereas macrophages obtained from mice with mutations in the FasR were totally resistant to Th1-mediated cytotoxicity. Macrophage cytotoxicity depended upon specific antigen recognition by T cells and was major histocompatibility complex restricted. These findings indicate that, in addition to deletion of activated lymphocytes, Fas plays an important role in deletion of activated macrophages after antigen presentation to Th1 CD4+ T cells. Failure to delete macrophages that constitutively present self-antigens may contribute to the expression of autoimmunity in mice deficient in FasR (lpr) or Fas ligand (gld). PMID:7479970

  7. High mobility group box 1 protein synergizes with lipopolysaccharide and peptidoglycan for nitric oxide production in mouse peritoneal macrophages in vitro.

    PubMed

    Chakraborty, Rituparna; Bhatt, Kunal H; Sodhi, Ajit

    2013-05-01

    Extracellular high mobility group box 1 (HMGB1) protein and nitric oxide (NO) has been credited with multiple inflammatory functions using in vivo and in vitro systems. Therefore, delineating their regulation may be an important therapeutic strategy for the treatment of sepsis. In the present study, it is demonstrated that recombinant HMGB1 (rHMGB1) synergizes with sub threshold concentration of TLR2 agonist (PGN; 1 μg/ml) as well as with TLR4 agonist (LPS; 1 ng/ml) to induce NO release in mouse peritoneal macrophages. The enhanced iNOS expression was also observed at the transcription and translational level. Co-incubation of macrophages with rHMGB1 with either PGN or LPS showed enhanced expression of TLR2, TLR4 and RAGE. TLR2, TLR4 or RAGE knockdown macrophages effectively inhibited the rHMGB1+PGN or LPS induced NO synergy. It was further observed that the JNK MAPK inhibitor SP600125 attenuated the PGN+rHMGB1 induced iNOS/NO synergy whereas p38 MAPK inhibitor SB908912 inhibited iNOS/NO synergy induced by LPS+rHMGB1. It was also observed that the activation of NF-κB is essential for the synergy as the pharmacological inhibition or siRNA knockdown of NF-κB (cRel) significantly reduced the rHMGB1+PGN or rHMGB1+LPS induced enhanced iNOS/NO expression. Altogether, the data suggests that the co-incubation of macrophages with rHMGB1 with either LPS or PGN induces the synergistic effect on iNOS expression and NO release by the upregulation of surface receptors (TLR2, TLR4 and RAGE) which in turn amplifies the MAPKs (p38 and JNK) and NF-κB activation and results in enhanced iNOS expression and NO production.

  8. Physical Activity in Patients Treated With Peritoneal Dialysis

    PubMed Central

    Thangarasa, Tharshika; Imtiaz, Rameez; Hiremath, Swapnil; Zimmerman, Deborah

    2017-01-01

    Background: Patients with chronic diseases are known to benefit from exercise. Despite a lack of compelling evidence, patients with end-stage kidney disease treated with peritoneal dialysis are often discouraged from participating in exercise programs that include resistance training due to concerns about the development of hernias and leaks. The actual effects of physical activity with or without structured exercise programs for these patients remain unclear. The purpose of this study is to more completely define the risks and benefits of physical activity in the end-stage kidney disease population treated with peritoneal dialysis. Methods/design: We will conduct a systematic review examining the effects of physical activity on end-stage kidney disease patients treated with peritoneal dialysis. For the purposes of this review, exercise will be considered a purposive subcategory of physical activity. The primary objective is to determine if physical activity in this patient population is associated with improvements in mental health, physical functioning, fatigue and quality of life and if there is an increase in adverse outcomes. With the help of a skilled librarian, we will search MEDLINE, EMBASE, CINAHL, and Cochrane Central Register of Controlled Trials for randomized trials and observational studies. We will include adult end-stage kidney disease patients treated with peritoneal dialysis that have participated in an exercise training program or had their level of physical activity assessed directly or by self-report. The study must include an assessment of the association between physical activity and one of our primary or secondary outcomes measures. We will report study quality using the Cochrane Risk of Bias Assessment Tool for randomized controlled trials and the Newcastle–Ottawa Scale for observational studies. Quality across studies will be assessed using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach. The

  9. The Many Alternative Faces of Macrophage Activation.

    PubMed

    Hume, David A

    2015-01-01

    Monocytes and macrophages provide the first line of defense against pathogens. They also initiate acquired immunity by processing and presenting antigens and provide the downstream effector functions. Analysis of large gene expression datasets from multiple cells and tissues reveals sets of genes that are co-regulated with the transcription factors that regulate them. In macrophages, the gene clusters include lineage-specific genes, interferon-responsive genes, early inflammatory genes, and genes required for endocytosis and lysosome function. Macrophages enter tissues and alter their function to deal with a wide range of challenges related to development and organogenesis, tissue injury, malignancy, sterile, or pathogenic inflammatory stimuli. These stimuli alter the gene expression to produce "activated macrophages" that are better equipped to eliminate the cause of their influx and to restore homeostasis. Activation or polarization states of macrophages have been classified as "classical" and "alternative" or M1 and M2. These proposed states of cells are not supported by large-scale transcriptomic data, including macrophage-associated signatures from large cancer tissue datasets, where the supposed markers do not correlate with other. Individual macrophage cells differ markedly from each other, and change their functions in response to doses and combinations of agonists and time. The most studied macrophage activation response is the transcriptional cascade initiated by the TLR4 agonist lipopolysaccharide. This response is reviewed herein. The network topology is conserved across species, but genes within the transcriptional network evolve rapidly and differ between mouse and human. There is also considerable divergence in the sets of target genes between mouse strains, between individuals, and in other species such as pigs. The deluge of complex information related to macrophage activation can be accessed with new analytical tools and new databases that provide

  10. Depolymerization of macrophage microfilaments prevents induction and inhibits activity of nitric oxide synthase.

    PubMed

    Fernandes, P D; Araujo, H M; Riveros-Moreno, V; Assreuy, J

    1996-12-01

    We have investigated the relationship between peritoneal murine macrophage cytoskeleton and nitric oxide (NO) synthase (NOS). Activation of the cells with lipopolysaccharide plus interferon-gamma (LI) induced iNOS, detected by nitrite or by labeled L-citrulline production and by a specific antibody against macrophage iNOS. Addition of cytochalasin B (a microfilament-depolymerizing agent) caused a dose-dependent inhibition in NO production by macrophages, whereas colchicine (a microtubule depolymerizing agent) inhibited it only by 20% and not dose-dependently. Addition of cytochalasin B together with LI abolished nitrite and L-citrulline accumulation as well as the amount of iNOS antigen in activated macrophage. Moreover, addition of cytochalasin B 6 or 12 h after stimulus, also decreased the nitrite and L-citrulline production by macrophages although iNOS antigen content by Western blot was the same in the presence or in the absence of cytochalasin B added 12 h after activation. Since cytochalasin B failed to inhibit iNOS activity directly, its inhibitory effects on NO production by macrophages is likely to be indirect, through microfilament network in central regions of cells, but not in filaments seen at pseudopodia or edging processes. Our findings demonstrate that disruption of microfilaments but not of microtubules prevents the iNOS induction process and inhibits its enzymatic activity in activated macrophages.

  11. Injection of mice with antibody to mouse interferon alpha/beta decreases the level of 2'-5' oligoadenylate synthetase in peritoneal macrophages.

    PubMed Central

    Gresser, I; Vignaux, F; Belardelli, F; Tovey, M G; Maunoury, M T

    1985-01-01

    Injection of conventional or axenic weanling mice with potent sheep or goat antibody to mouse interferon alpha/beta resulted in a decrease in the basal level of 2-5A synthetase in resting peritoneal macrophages and rendered these cells permissive for vesicular stomatitis virus. There was a good inverse correlation between the level of 2-5A synthetase in peritoneal macrophages and the permissivity of these cells for vesicular stomatitis virus. The peritoneal macrophages of 1- and 2-week-old mice had low levels of 2-5A synthetase and were permissive for vesicular stomatitis virus, whereas at 3 weeks (and after) there was a marked increase in the level of 2-5A synthetase in peritoneal macrophages, and these cells were no longer permissive for vesicular stomatitis virus. We suggest that low levels of interferon alpha or beta or both are produced in normal mice, and that this interferon contributes to host defense by inducing and maintaining an antiviral state in some cells. PMID:2981340

  12. Morphological and biochemical changes during formocresol induced cell death in murine peritoneal macrophages: apoptotic and necrotic features.

    PubMed

    Cardoso, María Lorena; Todaro, Juan Santiago; Aguirre, María Victoria; Juaristi, Julián Antonio; Brandan, Nora Cristina

    2010-10-01

    The present study was conducted to investigate the role of Formocresol (FC)-induced apoptosis and necrotic cell death in murine peritoneal macrophages (pMø). Macrophages were cultured with 1:100 FC for 2 to 24 h. The viability (trypan blue assay), cell morphology (scanning electronic microscope), and apoptotic and necrotic indexes (light and fluorescent microscopy) were determined at different scheduled times. Simultaneously, the expressions of proteins related to stress, survival, and cell death were measured by western blotting. FC-exposed macrophages exhibited maximal apoptosis from 2 to 6 h, coincident with Bax overexpression (P < 0.001). Additionally, Bcl-x(L) showed maximal expression between 12 and 24 h suggesting its survival effect in pMø. The lowest pMø viability and the increment of the necrotic rate from 4 to 12 h were observed in accordance to Fas and Hsp60 overexpressions. In summary, all the experimental data suggest that two different pathways emerge in pMø exposed to FC, one leading Bax-dependent apoptosis (2-6 h) and the other one favoring necrosis (4-18 h), related to Fas-receptor and Hsp60 stress signal.

  13. The Many Alternative Faces of Macrophage Activation

    PubMed Central

    Hume, David A.

    2015-01-01

    Monocytes and macrophages provide the first line of defense against pathogens. They also initiate acquired immunity by processing and presenting antigens and provide the downstream effector functions. Analysis of large gene expression datasets from multiple cells and tissues reveals sets of genes that are co-regulated with the transcription factors that regulate them. In macrophages, the gene clusters include lineage-specific genes, interferon-responsive genes, early inflammatory genes, and genes required for endocytosis and lysosome function. Macrophages enter tissues and alter their function to deal with a wide range of challenges related to development and organogenesis, tissue injury, malignancy, sterile, or pathogenic inflammatory stimuli. These stimuli alter the gene expression to produce “activated macrophages” that are better equipped to eliminate the cause of their influx and to restore homeostasis. Activation or polarization states of macrophages have been classified as “classical” and “alternative” or M1 and M2. These proposed states of cells are not supported by large-scale transcriptomic data, including macrophage-associated signatures from large cancer tissue datasets, where the supposed markers do not correlate with other. Individual macrophage cells differ markedly from each other, and change their functions in response to doses and combinations of agonists and time. The most studied macrophage activation response is the transcriptional cascade initiated by the TLR4 agonist lipopolysaccharide. This response is reviewed herein. The network topology is conserved across species, but genes within the transcriptional network evolve rapidly and differ between mouse and human. There is also considerable divergence in the sets of target genes between mouse strains, between individuals, and in other species such as pigs. The deluge of complex information related to macrophage activation can be accessed with new analytical tools and new databases

  14. Peroxisome proliferator-activated receptor-gamma agonist rosiglitazone attenuates postincisional pain by regulating macrophage polarization

    SciTech Connect

    Hasegawa-Moriyama, Maiko; Ohnou, Tetsuya; Godai, Kohei; Kurimoto, Tae; Nakama, Mayo; Kanmura, Yuichi

    2012-09-14

    Highlights: Black-Right-Pointing-Pointer Rosiglitazone attenuated postincisional pain. Black-Right-Pointing-Pointer Rosiglitazone alters macrophage polarization to F4/80{sup +}CD206{sup +} M2 macrophages at the incisional sites. Black-Right-Pointing-Pointer Transplantation of rosiglitazone-treated macrophages produced analgesic effects. -- Abstract: Acute inflammation triggered by macrophage infiltration to injured tissue promotes wound repair and may induce pain hypersensitivity. Peroxisome proliferator-activated receptor {gamma} (PPAR){gamma} signaling is known to regulate heterogeneity of macrophages, which are often referred to as classically activated (M1) and alternatively activated (M2) macrophages. M1 macrophages have considerable antimicrobial activity and produce a wide variety of proinflammatory cytokines. In contrast, M2 macrophages are involved in anti-inflammatory and homeostatic functions linked to wound healing and tissue repair. Although it has been suggested that PPAR{gamma} agonists attenuate pain hypersensitivity, the molecular mechanism of macrophage-mediated effects of PPAR{gamma} signaling on pain development has not been explored. In this study, we investigated the link between the phenotype switching of macrophage polarization induced by PPAR{gamma} signaling and the development of acute pain hypersensitivity. Local administration of rosiglitazone significantly ameliorated hypersensitivity to heat and mechanical stimuli, and paw swelling. Consistent with the down-regulation of nuclear factor {kappa}B (NF{kappa}B) phosphorylation by rosiglitazone at the incisional sites, the number of F4/80{sup +}iNOS{sup +} M1 macrophages was decreased whereas numbers of F4/80{sup +}CD206{sup +} M2 macrophages were increased in rosiglitazone-treated incisional sites 24 h after the procedure. In addition, gene induction of anti-inflammatory M2-macrophage-associated markers such as arginase1, FIZZ1 and interleukin (IL)-10 were significantly increased, whereas

  15. Effect of lipopolysaccharide on thymidine salvage as related to macrophage activation.

    PubMed Central

    Harada, Y; Nagao, S; Nakamura, M; Okada, F; Tanigawa, Y

    1995-01-01

    Lipopolysaccharide (LPS), known as one of the potent activators of macrophages, has inhibitory effects on the proliferation of normal macrophages and macrophage-like cell lines. We report here that LPS dose- and time-dependently suppressed the tritiated thymidine ([3H]TdR) incorporation into the acid-insoluble fraction with a significant inverse correlation to the tumour necrosis factor-alpha (TNF) production in the J774.1 macrophage cell line. Among the three tested enzymes involved in DNA synthesis, only thymidine kinase (TK) activity decreased progressively in parallel with the decline in [3H]TdR incorporation, reaching 97% inhibition within 12 hr of LPS treatment, while changes in the activities of other two enzymes, DNA polymerase alpha and thymidylate synthase (TS), were less significant. On the other hand, LPS inhibited the cell proliferation only incompletely, as judged by 62% inhibition of cell growth at 36 hr. Even in the experiments done in a TdR-free medium, cell growth was inhibited by LPS to the same extent, suggesting that TK was not directly involved in the proliferation of J774 cells. LPS also inhibited the conversion of TdR to thymidine monophosphate (TMP) in murine peritoneal exudate macrophages (PEM). Thus LPS-induced suppression of TdR salvage related to TNF production is common in both normal and neoplastic macrophages, and therefore may be of potential importance in the process of macrophage activation. PMID:7751001

  16. Different effects of the immunomodulatory drug GMDP immobilized onto aminopropyl modified and unmodified mesoporous silica nanoparticles upon peritoneal macrophages of women with endometriosis.

    PubMed

    Antsiferova, Yuliya; Sotnikova, Nataliya; Parfenyuk, Elena

    2013-01-01

    The aim of the present work was to compare in vitro the possibility of application of unmodified silica nanoparticles (UMNPs) and modified by aminopropyl groups silica nanoparticles (AMNPs) for topical delivery of immunomodulatory drug GMDP to the peritoneal macrophages of women with endometriosis. The absence of cytotoxic effect and high cellular uptake was demonstrated for both types of silica nanoparticles. The immobilization of GMDP on the UMNPs led to the suppression of the stimulatory effect of GMDP on the membrane expression of scavenger receptors SR-AI and SR-B, mRNAs expression of NOD2 and RAGE, and synthesis of proteolytic enzyme MMP-9 and its inhibitor TIMP-1. GMDP, immobilized onto AMNPs, enhanced the initially reduced membrane expression of SRs and increased NOD2, RAGE, and MMP-9 mRNAs expression by macrophages. Simultaneously high level of mRNAs expression of factors, preventing undesirable hyperactivation of peritoneal macrophages (SOCS1 and TIMP-1), was observed in macrophages incubated in the presence of GMDP, immobilized onto AMNPs. The effect of AMNPs immobilized GMDP in some cases exceeded the effect of free GMDP. Thus, among the studied types of silica nanoparticles, AMNPs are the most suitable nanoparticles for topical delivery of GMDP to the peritoneal macrophages.

  17. The macrophage chemotactic activity of Edwardsiella tarda extracellular products

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The chemoattractant capabilities of Edwardsiella tarda extracellular products (ECP) were investigated from two isolates, the virulent FL6-60 parent and less virulent RET-04 mutant. Chemotaxis and chemokinesis were assayed in vitro using blind well chambers with peritoneal macrophages obtained from ...

  18. Involvement of proton-sensing receptor TDAG8 in the anti-inflammatory actions of dexamethasone in peritoneal macrophages

    SciTech Connect

    He, Xiao-dong; Tobo, Masayuki; Mogi, Chihiro; Nakakura, Takashi; Komachi, Mayumi; Murata, Naoya; Takano, Mutsumi; Tomura, Hideaki; Sato, Koichi; Okajima, Fumikazu

    2011-12-02

    Highlights: Black-Right-Pointing-Pointer Glucocorticoid (GC) induced the expression of proton-sensing TDAG8 in macrophages. Black-Right-Pointing-Pointer GC enhanced acidic pH-induced cAMP accumulation and inhibition of TNF-{alpha} production. Black-Right-Pointing-Pointer The enhancement of the GC-induced actions was lost by TDAG8 deficiency. Black-Right-Pointing-Pointer GC-induced anti-inflammatory actions are partly mediated by TDAG8 expression. -- Abstract: Dexamethasone (DEX), a potent glucocorticoid, increased the expression of T-cell death associated gene 8 (TDAG8), a proton-sensing G protein-coupled receptor, which is associated with the enhancement of acidic pH-induced cAMP accumulation, in peritoneal macrophages. We explored the role of increased TDAG8 expression in the anti-inflammatory actions of DEX. The treatment of macrophages with either DEX or acidic pH induced the cell death of macrophages; however, the cell death was not affected by TDAG8 deficiency. While DEX inhibited lipopolysaccharide-induced production of tumor necrosis factor-{alpha}, an inflammatory cytokine, which was independent of TDAG8, at neutral pH, the glucocorticoid enhanced the acidic pH-induced inhibition of tumor necrosis factor-{alpha} production in a manner dependent on TDAG8. In conclusion, the DEX-induced increase in TDAG8 expression is in part involved in the glucocorticoid-induced anti-inflammatory actions through the inhibition of inflammatory cytokine production under the acidic pH environment. On the other hand, the role of TDAG8 in the DEX-induced cell death is questionable.

  19. Active Negative Pressure Peritoneal Therapy After Abbreviated Laparotomy

    PubMed Central

    Roberts, Derek J.; Faris, Peter D.; Ball, Chad G.; Kubes, Paul; Tiruta, Corina; Xiao, Zhengwen; Holodinsky, Jessalyn K.; McBeth, Paul B.; Doig, Christopher J.; Jenne, Craig N.

    2015-01-01

    Objective: To determine whether active negative pressure peritoneal therapy with the ABThera temporary abdominal closure device reduces systemic inflammation after abbreviated laparotomy. Background: Excessive systemic inflammation after abdominal injury or intra-abdominal sepsis is associated with poor outcomes. Methods: We conducted a single-center, randomized controlled trial. Forty-five adults with abdominal injury (46.7%) or intra-abdominal sepsis (52.3%) were randomly allocated to the ABThera (n = 23) or Barker's vacuum pack (n = 22). On study days 1, 2, 3, 7, and 28, blood and peritoneal fluid were collected. The primary endpoint was the difference in the plasma concentration of interleukin-6 (IL-6) 24 and 48 hours after temporary abdominal closure application. Results: There was a significantly lower peritoneal fluid drainage from the ABThera at 48 hours after randomization. Despite this, there was no difference in plasma concentration of IL-6 at baseline versus 24 (P = 0.52) or 48 hours (P = 0.82) between the groups. There was also no significant intergroup difference in the plasma concentrations of IL-1β, −8, −10, or −12 p70 or tumor necrosis factor α between these time points. The cumulative incidence of primary fascial closure at 90 days was similar between groups (hazard ratio, 1.6; 95% confidence interval, 0.82–3.0; P = 0.17). However, 90-day mortality was improved in the ABThera group (hazard ratio, 0.32; 95% confidence interval, 0.11–0.93; P = 0.04). Conclusions: This trial observed a survival difference between patients randomized to the ABThera versus Barker's vacuum pack that did not seem to be mediated by an improvement in peritoneal fluid drainage, fascial closure rates, or markers of systemic inflammation. Trial Registration: ClinicalTrials.gov identifier NCT01355094. PMID:25536308

  20. Development of multiple necrotizing enteritis induced by a tumor necrosis factor-like cytokine from lipopolysaccharide-stimulated peritoneal macrophages in rats.

    PubMed Central

    Torimoto, K.; Sato, N.; Okubo, M.; Yagihashi, A.; Wada, Y.; Hara, I.; Hayasaka, H.; Kikuchi, K.

    1990-01-01

    We report the development of an animal model of multiple necrotizing enteritis (MNE) in rats. When rats were injected directly with a culture supernatant of lipopolysaccharide (LPS)-stimulated rat peritoneal macrophages into the abdominal aorta, the overt pathologic lesions of MNE developed within 30 minutes after injection. The rats showed an elevated level of blood fibrinogen degradation product content even 30 minutes after injection. Furthermore the rats that were pretreated intravenously with heparin sulfate did not develop MNE, indicating the acute disturbances of blood microcirculation in the intestine. Multiple necrotizing enteritis was developed also by the injection with recombinant tumor necrosis factor (rTNF) but rarely was observed with even a high dose of recombinant interleukin-1 (rIL-1) or platelet-activating factor (PAF). The supernatant was cytotoxic in vitro to TNF-susceptible LM and many other cells but was less cytotoxic to the TNF-resistant LR line. Partial purification of the supernatant suggested that the supernatant contained a cytokine that has biochemical features of TNF. Furthermore polyclonal anti-TNF antibody could inhibit not only the cytotoxicity in vitro but also MNE development in vivo by this factor. These data strongly indicate that MNE possibly could be caused by a TNF-like cytokine produced by macrophages that are stimulated by the endotoxin. Images Figure 1 PMID:2240161

  1. Pyrimidinergic Receptor Activation Controls Toxoplasma gondii Infection in Macrophages

    PubMed Central

    Moreira-Souza, Aline Cristina Abreu; Marinho, Ygor; Correa, Gladys; Santoro, Giani França; Coutinho, Claudia Mara Lara Melo; Vommaro, Rossiane Claudia; Coutinho-Silva, Robson

    2015-01-01

    Infection by the protozoan parasite Toxoplasma gondii is highly prevalent worldwide and may have serious clinical manifestations in immunocompromised patients. T. gondii is an obligate intracellular parasite that infects almost any cell type in mammalian hosts, including immune cells. The immune cells express purinergic P2 receptors in their membrane – subdivided into P2Y and P2X subfamilies - whose activation is important for infection control. Here, we examined the effect of treatment with UTP and UDP in mouse peritoneal macrophages infected with T. gondii tachyzoites. Treatment with these nucleotides reduced parasitic load by 90%, but did not increase the levels of the inflammatory mediators NO and ROS, nor did it modulate host cell death by apoptosis or necrosis. On the other hand, UTP and UDP treatments induced early egress of tachyzoites from infected macrophages, in a Ca2+-dependent manner, as shown by scanning electron microscopy analysis, and videomicroscopy. In subsequent infections, prematurely egressed parasites had reduced infectivity, and could neither replicate nor inhibit the fusion of lysosomes to the parasitophorous vacuole. The use of selective agonists and antagonists of the receptor subtypes P2Y2 and P2Y4 and P2Y6 showed that premature parasite egress may be mediated by the activation of these receptor subtypes. Our results suggest that the activity of P2Y host cell receptors controls T. gondii infection in macrophages, highlighting the importance of pyrimidinergic signaling for innate immune system response against infection. Finally the P2Y receptors should be considered as new target for the development of drugs against T. gondii infection. PMID:26192447

  2. Effects of arginine supplementation on antioxidant enzyme activity and macrophage response in burned mice.

    PubMed

    Tsai, Hui-Ju; Shang, Huey-Fang; Yeh, Chiu-Li; Yeh, Sung-Ling

    2002-05-01

    This study investigated the effect of arginine (Arg) supplementation on antioxidant enzyme activities and macrophage response in burned mice. Experiment 1: 60 male BALB/c mice were assigned to two groups. One group was fed a control diet with casein as the protein source, the other group was supplemented with 2% Arg in addition to casein. The two groups were isonitrogenous. After 4 weeks, all mice received a 30% body surface area burn injury. The antioxidant enzyme activities and lipid peroxides in the tissues were analyzed. Experiment 2: 20 mice were divided into two groups and burn injury was induced after feeding for 4 weeks as described in experiment 1. Twenty-four hours after the burn, tumor necrosis factor-alpha (TNF-alpha) secreted by cultured peritoneal macrophages was measured. The results show that antioxidant enzyme activities and lipid peroxides in tissues tended to be lower in the Arg group than in the control group after the burn. Production of TNF-alpha by peritoneal macrophages after stimulation with lipopolysacchride (LPS) was significantly elevated in the Arg group, whereas no response was observed in the control group. These results suggest that dietary Arg supplementation attenuates the oxidative stress induced by burn injury, and a better macrophage response was observed when Arg was administered.

  3. Role of resident macrophages, peripheral neutrophils, and translymphatic absorption in bacterial clearance from the peritoneal cavity

    SciTech Connect

    Dunn, D.L.; Barke, R.A.; Knight, N.B.; Humphrey, E.W.; Simmons, R.L.

    1985-08-01

    Microbial pathogens within the peritoneal cavity are thought to encounter three categories of host defense mechanisms: (i) removal mechanisms, which occur via diaphragmatic lymphatic absorption; (ii) killing mechanisms, in which host phagocytes act as effector cells; and (iii) sequestration mechanisms due to fibrin trapping and the formation of adhesions between visceral surfaces. The authors sought to define and quantitate the relative role of the first two components in an experimental rat model of Escherichia coli peritonitis in which fibrinous adhesions do not form. Intraperitoneal challenge with greater than or equal to 2 X 10(8) CFU of viable E. coli led to an initial decline in bacterial numbers followed by ongoing proliferation and greater than 50% mortality. With inocula of less than or equal to 5 X 10(7) CFU, elimination of bacteria occurred after moderate initial proliferation, and no mortality ensued. Nonviable, radiolabeled E. coli organisms were utilized to examine bacterial clearance via translymphatic absorption and phagocytosis. Both processes were extremely rapid, serving to eliminate free bacteria rapidly within the peritoneal cavity.

  4. Killing of virulent Mycobacterium tuberculosis by reactive nitrogen intermediates produced by activated murine macrophages

    PubMed Central

    1992-01-01

    Tuberculosis remains one of the major infectious causes of morbidity and mortality in the world, yet the mechanisms by which macrophages defend against Mycobacterium tuberculosis have remained obscure. Results from this study show that murine macrophages, activated by interferon gamma, and lipopolysaccharide or tumor necrosis factor alpha, both growth inhibit and kill M. tuberculosis. This antimycobacterial effect, demonstrable both in murine macrophage cell lines and in peritoneal macrophages of BALB/c mice, is independent of the macrophage capacity to generate reactive oxygen intermediates (ROI). Both the ROI-deficient murine macrophage cell line D9, and its ROI-generating, parental line J774.16, expressed comparable antimycobacterial activity upon activation. In addition, the oxygen radical scavengers superoxide dismutase (SOD), catalase, mannitol, and diazabicyclooctane had no effect on the antimycobacterial activity of macrophages. These findings, together with the results showing the relative resistance of M. tuberculosis to enzymatically generated H2O2, suggest that ROI are unlikely to be significantly involved in killing M. tuberculosis. In contrast, the antimycobacterial activity of these macrophages strongly correlates with the induction of the L-arginine- dependent generation of reactive nitrogen intermediates (RNI). The effector molecule(s) that could participate in mediating this antimycobacterial function are toxic RNI, including NO, NO2, and HNO2, as demonstrated by the mycobacteriocidal effect of acidified NO2. The oxygen radical scavenger SOD adventitiously perturbs RNI production, and cannot be used to discriminate between cytocidal mechanisms involving ROI and RNI. Overall, our results provide support for the view that the L-arginine-dependent production of RNI is the principal effector mechanism in activated murine macrophages responsible for killing and growth inhibiting virulent M. tuberculosis. PMID:1552282

  5. Activation of Cannabinoid Receptor 2 Ameliorates DSS-Induced Colitis through Inhibiting NLRP3 Inflammasome in Macrophages

    PubMed Central

    Xu, Zhe-Qi; Wei, Wei; Han, Bin-Ze; Chen, Xiong-Wen; Su, Ding-Feng; Liu, Chong

    2016-01-01

    Activation of cannabinoid receptor 2 (CB2R) ameliorates inflammation, but the underlying mechanism remains unclear. In the present study, we examined whether activation of CB2R could suppress the nucleotide-binding domain and leucine-rich repeat protein 3 (NLRP3) inflammasome. In peritoneal macrophages isolated from C57BL/6 mice, LPS/DSS challenge for 24 h increased the expression of the components of NLRP3 inflammasome NLRP3, Casp-1 p20/Casp-1 p45 ratio, proIL-1β and IL-1β and also enhanced autophagy (LC3-II/LC3-I ratio, Beclin-1 and SQSTM1). Pretreatment of peritoneal macrophages with HU 308, a selective CB2R agonist, attenuated LPS/DSS-induced NLRP3 inflammasome activation, but further enhanced autophagy. In comparison with wild-type (WT) control, peritoneal macrophages from CB2R knockout (KO) mice had more robust NLRP3 inflammasome activation and attenuated autophagy upon LPS/DSS challenge. Knockdown autophagy-related gene 5 (Atg5) with a siRNA in peritoneal macrophages attenuated the inhibitory effects of HU 308 on LPS/DSS-induced NLRP3 inflammasome activation in vitro. In vivo, HU308 treatment attenuated DSS-induced colitis mice associated with reduced colon inflammation and inhibited NLRP3 inflammasome activation in wild-type mice. In CB2R KO mice, DSS-induced inflammation and NLRP3 inflammasome activation were more pronounced than those in WT control. Finally, we demonstrated that AMPK-mTOR-P70S6K signaling pathway was involved in this CB2R-mediated process. We conclude that activation of CB2R ameliorates DSS-induced colitis through enhancing autophagy that may inhibit NLRP3 inflammasome activation in macrophages. PMID:27611972

  6. Mechanisms of glucocorticoid induced suppression of phagocytosis in murine peritoneal macrophage cultures

    SciTech Connect

    Becker, J.L.

    1986-01-01

    Glucocorticoids suppress phagocytosis of heat killed Saccharomyces cerevisiae in macrophage cultures. In order to determine the mechanisms by which this response occurs, this investigation was initiated to examine whether the suppression of phagocytosis is mediated by a steroid induced phagocytosis inhibitory protein (PIP). Furthermore, it is postulated that these suppressive effects may be associated with alterations in macrophage phospholipid metabolism. To assess the association between phospholipid metabolism and phagocytosis, control and 1 ..mu..M dexamethasone treated macrophages were exposed to the phospholipase inhibitor bromophenacylbromide. The enzyme inhibitor suppressed phagocytosis in a time and dose dependent manner. However, supplying dexamethasone treated cultures with arachidonate did not reverse the steroid induced suppression of phagocytosis, whether the arachidonate was supplied alone or together with indomethacin and nordihydroguaiaretic acid. Control cells, prelabeled with /sup 3/H-arachidonate, exhibited an increased percentage of the radiolabeled fatty acid in neutral lipids following phagocytosis, with a corresponding decrease in the percentage associated with phosphatidylcholine.

  7. Lipophilic derivative of muramyl dipeptide is more active than muramyl dipeptide in priming macrophages to release superoxide anion.

    PubMed Central

    Pabst, M J; Cummings, N P; Shiba, T; Kusumoto, S; Kotani, S

    1980-01-01

    Mouse peritoneal macrophages, when treated with a lipophilic derivative of muramyl dipeptide either in vitro or in vivo by intraperitoneal injection, showed a more than fivefold increase in their ability to generate superoxide anion after stimulation of the macrophages with phorbol myristate acetate. This response was more than twice that observed with the parent molecule, muramyl dipeptide (MDP). Unlike MDP, which has a systemic effect, the lipophilic derivative, [B30]-MDP, did not alter the response of peritoneal macrophages when given subcutaneously in the flank, suggesting that [B30]-MDP remains localized at the site of injection. The enhanced effect of [B30]-MDP over MDP appeared to be due to the inherent lipophilicity of the molecule, and was probably not due to either stimulation of T lymphocytes or activation of the alternative pathway of complement. PMID:6260655

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

    PubMed

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

    2015-01-01

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

  9. TLR4-mediated activation of mouse macrophages by Korean mistletoe lectin-C (KML-C).

    PubMed

    Park, Hong-Jai; Hong, Ju-ho; Kwon, Hyung-Joon; Kim, Youngchan; Lee, Kwan-Hee; Kim, Jong-Bae; Song, Seong K

    2010-06-04

    Korean mistletoe lectin (KML-C) is an adjuvant that activates systemic and mucosal immune cells to release cytokines including TNF-alpha, which induces immunity against viruses and cancer cells. Although the immunomodulatory activity of KML-C has been well established, the underlying mechanism of action of KML-C has yet to be explored. When mouse peritoneal macrophages were treated with KML-C, both transcription and translation of TLR4 were upregulated. KML-C-induced TLR4 downstream events were similar to those activated by LPS: the upregulation of interleukin-1 receptor-associated kinase-1 (IRAK1); resulting in macrophage activation and TNF-alpha production. When TLR4 was blocked using a TLR4-specific neutralizing antibody, TNF-alpha production from the macrophages was significantly inhibited. Moreover, TLR4-deficient mouse macrophages treated with KML-C also secreted greatly reduced level of TNF-alpha secretion. Finally, TLR4 molecules were co-precipitated with KML-C, to which agarose beads were conjugated, indicating that those molecules are associated. These data indicate that KML-C activates mouse macrophages to secrete TNF-alpha by interacting with the TLR4 molecule and activating its signaling pathways.

  10. Influence of cadmium on isolated peritoneal macrophage populations: cadmium inhibits Fc receptor internalization

    SciTech Connect

    Cook, G.B.

    1985-01-01

    In vitro experiments were performed to examine the effect of cadmium on adherent phagocytic cell populations. The authors were able to demonstrate, in vitro, a phagocytic defect that was originally observed in an in vivo system. Using in vitro methodologies, cadmium was found to inhibit opsonin-dependent but not opsonin-independent phagocytosis in two different populations of macrophages. The receptors through which the opsonized /sup 51/Cr-ElgG were internalized were characterized as Fc receptors. They were able to demonstrate that cadmium could reversibly inhibit internalization of Fc receptors. This mechanism, rather than an alteration of the receptors' binding capabilities, was responsible for the observed inhibition of Fc mediated (opsonin-dependent) phagocytosis in both populations of macrophages tested. The defect was not specific for cadmium per se. Zinc treatment caused a similar inhibition of Fc receptor mediated phagocytosis.

  11. Action of the anti-tumoral zinc(II)phthalocyanine in solution or encapsulated into nanoparticles of poly-ɛ-caprolactone internalized by peritoneal macrophages

    NASA Astrophysics Data System (ADS)

    da Silva Abe, Amanda Santos Franco; Ricci-Júnior, Eduardo; Teixeira Lima Castelo Branco, Morgana; de Brito Gitirana, Lycia

    2016-09-01

    Nanoparticles (NPs) have been used as drug delivery systems (DDS) exhibiting high cell penetration power. As an antitumor photosensitizer, zinc(II) phthalocyanine (ZnPc) was applied in photodynamic therapy (PDT) since its phototoxic activity promotes death of tumor cells in the presence of laser light. Since drugs do not interact only with tumor cells in living organisms, this study aimed to analyze the action of ZnPc-loaded in nanoparticles (ZnPc-NPs) and in solution (free ZnPc) using peritoneal macrophages as a model of non-neoplastic cells that inhabit the tumoral stroma. NPs were produced by emulsion and evaporation of solvent and characterized by dynamic light scattering and transmission electron microscopy. Assays as 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide, light microscopy and laser scanning confocal microscopy were performed to evaluate the drug effects in the presence or absence of laser light applied in PDT. NPs exhibited dimensions between 290 and 350 nm and rounded shape. Empty NP did not affect cell viability, showing that these nanocarriers are biocompatible DDS. Free ZnPc was randomly distributed in the cytoplasm, while ZnPc-NP was preferably located near the nucleus. At 5 μg ml-1, free ZnPc caused greater loss of cell viability in the absence of laser when compared to ZnPc-NPs, in the presence or absence of irradiation. In contrast, free ZnPc and ZnPc-NPs (0.5 μg ml-1) promoted cell death to the same extent in cells treated with laser light or not. This demonstrates that the performance of this drug is dose dependent in its free form, but not in its nanoencapsulated form. Cells irradiated with laser (100 mW) and treated with free ZnPc or with ZnPc-NPs showed morphological changes. These observations show that both free ZnPc and ZnPc-NPs irradiated with laser light cause cell damage in peritoneal macrophages.

  12. Diagnostic utility of a direct immunofluorescence test to detect feline coronavirus antigen in macrophages in effusive feline infectious peritonitis.

    PubMed

    Litster, A L; Pogranichniy, R; Lin, T-L

    2013-11-01

    The antemortem diagnosis of feline infectious peritonitis (FIP) remains challenging in clinical practice, since current testing methods have suboptimal diagnostic accuracy. Immunohistochemical testing of biopsy specimens and postmortem examination are the standard diagnostic methods, although direct immunofluorescence (DIF) testing to detect feline coronavirus in macrophages in effusion specimens has been reported to have 100% specificity and has been recommended as an antemortem confirmatory test. The aim of this study was to compare the results of DIF testing in antemortem feline effusions with postmortem results using field samples. Effusion specimens were collected antemortem from 17 cats and tested by DIF, followed by postmortem examination. Histopathological examination of specimens collected at postmortem confirmed FIP in 10/17 cases and ruled out FIP out in 7/17 cases. Antemortem DIF testing was positive in all 10 cases confirmed as FIP at postmortem examination. In the seven cats where FIP was ruled out at postmortem examination, DIF was negative in five cases and positive in the remaining two cases. The calculated sensitivity of DIF testing was 100% and the specificity was 71.4%. Duplicate effusion specimens from eight cats that were initially DIF positive were stored refrigerated (4 °C) or at room temperature (22-25 °C) and subjected to serial DIF testing to determine the duration of positive results. DIF-positive specimens stored at both temperatures retained their positive status for at least 2 days.

  13. Sodium-cromoglycate (Cromolyn) selectively increases the binding and phagocytosis of unsensitized target cells by rat peritoneal macrophages.

    PubMed

    Miklós, K; Tolnay, M; Medgyesi, G A

    1996-09-01

    The influence of sodium-cromoglycate (cromolyn) on the binding and ingestion of sheep erythrocytes (SRBC) by elicited rat peritoneal macrophages (M phi) was studied using unsensitized SRBC. SRBC sensitized by homologous IgG or by IgM and complement as target cells. Preincubation of M phi with the drug (1 nM/1-2 mM/1) markedly enhanced both binding and ingestion of uncoated SRBC. The IgG-related increment in binding and phagocytosis was not significantly influenced by the drug. When target cells were coated by IgM and complement cromolyn pretreatment was ineffective. Preincubation of M phi by bovine brain gangliosides (BBG) diminished the cromolyn-induced enhancement of target cell binding and phagocytosis. When SRBC were pretreated by BBG, an increase of binding and phagocytosis was observed. These data suggest that cromoglycate may enhance the capacity of M phi to bind erythrocytes via ganglioside structures. Coating SRBC by complement components appears to interfere with binding of erythrocytes to M phi ganglioside receptors.

  14. Attachment, ingestion and intracellular killing of Helicobacter pylori by human peripheral blood mononuclear leukocytes and mouse peritoneal inflammatory macrophages.

    PubMed

    Chmiela, M; Paziak-Domanska, B; Wadström, T

    1995-02-01

    The different steps of phagocytosis, attachment, ingestion and intracellular killing of cells of Helicobacter pylori strain 17874 (expressing sialic acid-specific haemagglutinin) and cells of H. pylori strain 17875 (expressing non-sialic acid-specific haemagglutinin) have been studied. More cells of sialopositive H. pylori strain 17874 have been found attached to human peripheral blood mononuclear leukocytes (PBM) and mouse peritoneal inflammatory macrophages (PIM) than cells of sialonegative H. pylori strain 17875. Binding of cells of H. pylori strain 17874 has been significantly inhibited by treatment of phagocytes with neuraminidase. Inhibition of adhesion of these bacteria preincubated with foetuin to normal phagocytic cells has also been found. Well adhering cells of H. pylori strain 17874 were more resistant to killing mechanisms of human PBM and mouse PIM than cells of strain 17875. Good, probably sialic acid-specific haemagglutinin dependent, adhesion of H. pylori bacteria to phagocytes can be considered as an important virulence factor which facilitates the pathogen to avoid the defence mechanisms.

  15. NMAAP1 Expressed in BCG-Activated Macrophage Promotes M1 Macrophage Polarization.

    PubMed

    Liu, Qihui; Tian, Yuan; Zhao, Xiangfeng; Jing, Haifeng; Xie, Qi; Li, Peng; Li, Dong; Yan, Dongmei; Zhu, Xun

    2015-10-01

    Macrophages are divided into two subpopulations: classically activated macrophages (M1) and alternatively activated macrophages (M2). BCG (Bacilli Calmette-GuC)rin) activates disabled naC/ve macrophages to M1 macrophages, which act as inflammatory, microbicidal and tumoricidal cells through cell-cell contact and/or the release of soluble factors. Various transcription factors and signaling pathways are involved in the regulation of macrophage activation and polarization. We discovered that BCG-activated macrophages (BAM) expressed a new molecule, and we named it Novel Macrophage Activated Associated Protein 1 (NMAAP1). The current study found that the overexpression of NMAAP1 in macrophages results in M1 polarization with increased expression levels of M1 genes, such as inducible nitric oxide synthase (iNOS), tumor necrosis factor alpha (TNF-N1), Interleukin 6 (IL-6), Interleukin 12 (IL-12), Monocyte chemoattractant protein-1 (MCP-1) and Interleukin-1 beta (IL-1N2), and decreased expression of some M2 genes, such as Kruppel-like factor 4 (KLF4) and suppressor of cytokine signaling 1 (SOCS1), but not other M2 genes, including arginase-1 (Arg-1), Interleukin (IL-10), transforming growth factor beta (TGF-N2) and found in inflammatory zone 1 (Fizz1). Moreover, NMAAP1 overexpression in the RAW264.7 cell line increased cytotoxicity against MCA207 tumor cells, which depends on increased inflammatory cytokines rather than cell-cell contact. NMAAP1 also substantially enhanced the phagocytic ability of macrophages, which implies that NMAAP1 promoted macrophage adhesive and clearance activities. Our results indicate that NMAAP1 is an essential molecule that modulates macrophages phenotype and plays an important role in macrophage tumoricidal functions.

  16. Effect of Estragole on Leukocyte Behavior and Phagocytic Activity of Macrophages

    PubMed Central

    Wiirzler, Luiz Alexandre Marques; Silva-Filho, Saulo Euclides; Kummer, Raquel; Pedroso, Raissa Bocchi; Spironello, Ricardo Alexandre; Silva, Expedito Leite; Bersani-Amado, Ciomar Aparecida; Cuman, Roberto Kenji Nakamura

    2014-01-01

    Estragole, a chemical constituent of the essential oils of many aromatic plants, is used as flavoring in beverage and food industries. In vivo and in vitro experimental assays have shown that EST has sedative, anticonvulsant, antioxidant, antimicrobial, and anesthetic activity. In this work, we evaluate the effect of EST on leukocyte behavior and phagocytic activity of macrophages. In the peritonitis model, EST (500 and 750 mg/kg) decreased the infiltration of peritoneal exudate leukocytes. In vitro chemotaxis assay showed that EST (3, 10, 30, and 60 μg/mL) inhibited neutrophil migration toward fMLP. In the in vivo microcirculation assay, EST at doses of 250, 500, and 750 mg/kg significantly reduced the number of rolling and adherent leukocytes and at doses of 250 and 500 mg/kg decreased number of leukocyte migrated to perivascular tissue. The results showed that EST (3, 10, and 30 μg/mL) was able to stimulate the macrophages phagocytosis but only at concentration of 10 μg/mL promoted an increase in nitric oxide (NO) production. In conclusion, this study showed that EST had potential anti-inflammatory effects, likely by inhibiting leukocyte migration and by stimulating macrophages phagocytosis. PMID:25152763

  17. The peritoneal macrophage inflammatory profile in cirrhosis depends on the alcoholic or hepatitis C viral etiology and is related to ERK phosphorylation

    PubMed Central

    2012-01-01

    Background The development of ascites in cirrhotic patients generally heralds a deterioration in their clinical status. A differential gene expression profile between alcohol- and hepatitis C virus (HCV)-related cirrhosis has been described from liver biopsies, especially those associated with innate immune responses. The aim of this work was to identify functional differences in the inflammatory profile of monocyte-derived macrophages from ascites in cirrhotic patients of different etiologies in an attempt to extrapolate studies from liver biopsies to immune cells in ascites. To this end 45 patients with cirrhosis and non-infected ascites, distributed according to disease etiology, HCV (n = 15) or alcohol (n = 30) were studied. Cytokines and the cell content in ascites were assessed by ELISA and flow cytometry, respectively. Cytokines and ERK phosphorylation in peritoneal monocyte-derived macrophages isolated and stimulated in vitro were also determined. Results A different pattern of leukocyte migration to the peritoneal cavity and differences in the primed status of macrophages in cirrhosis were observed depending on the viral or alcoholic etiology. Whereas no differences in peripheral blood cell subpopulations could be observed, T lymphocyte, monocyte and polymorphonuclear cell populations in ascites were more abundant in the HCV than the alcohol etiology. HCV-related cirrhosis etiology was associated with a decreased inflammatory profile in ascites compared with the alcoholic etiology. Higher levels of IL-10 and lower levels of IL-6 and IL-12 were observed in ascitic fluid from the HCV group. Isolated peritoneal monocyte-derived macrophages maintained their primed status in vitro throughout the 24 h culture period. The level of ERK1/2 phosphorylation was higher in ALC peritoneal macrophages at baseline than in HCV patients, although the addition of LPS induced a greater increase in ERK1/2 phosphorylation in HCV than in ALC patients. Conclusions The

  18. Lysophosphatidylcholine Triggers TLR2- and TLR4-Mediated Signaling Pathways but Counteracts LPS-Induced NO Synthesis in Peritoneal Macrophages by Inhibiting NF-κB Translocation and MAPK/ERK Phosphorylation

    PubMed Central

    Carneiro, Alan Brito; Iaciura, Bruna Maria Ferreira; Nohara, Lilian Lie; Lopes, Carla Duque; Veas, Esteban Mauricio Cordero; Mariano, Vania Sammartino; Bozza, Patricia Torres; Lopes, Ulisses Gazos; Atella, Georgia Correa; Almeida, Igor Correia; Silva-Neto, Mário Alberto Cardoso

    2013-01-01

    Background Lysophosphatidylcholine (LPC) is the main phospholipid component of oxidized low-density lipoprotein (oxLDL) and is usually noted as a marker of several human diseases, such as atherosclerosis, cancer and diabetes. Some studies suggest that oxLDL modulates Toll-like receptor (TLR) signaling. However, effector molecules that are present in oxLDL particles and can trigger TLR signaling are not yet clear. LPC was previously described as an attenuator of sepsis and as an immune suppressor. In the present study, we have evaluated the role of LPC as a dual modulator of the TLR-mediated signaling pathway. Methodology/Principal Findings HEK 293A cells were transfected with TLR expression constructs and stimulated with LPC molecules with different fatty acid chain lengths and saturation levels. All LPC molecules activated both TLR4 and TLR2-1 signaling, as evaluated by NF-қB activation and IL-8 production. These data were confirmed by Western blot analysis of NF-қB translocation in isolated nuclei of peritoneal murine macrophages. However, LPC counteracted the TLR4 signaling induced by LPS. In this case, NF-қB translocation, nitric oxide (NO) synthesis and the expression of inducible nitric oxide synthase (iNOS) were blocked. Moreover, LPC activated the MAP Kinases p38 and JNK, but not ERK, in murine macrophages. Interestingly, LPC blocked LPS-induced ERK activation in peritoneal macrophages but not in TLR-transfected cells. Conclusions/Significance The above results indicate that LPC is a dual-activity ligand molecule. It is able to trigger a classical proinflammatory phenotype by activating TLR4- and TLR2-1-mediated signaling. However, in the presence of classical TLR ligands, LPC counteracts some of the TLR-mediated intracellular responses, ultimately inducing an anti-inflammatory phenotype; LPC may thus play a role in the regulation of cell immune responses and disease progression. PMID:24312681

  19. Treponemal infection specifically enhances node T-cell regulation of macrophage activity.

    PubMed Central

    Tabor, D R; Bagasra, O; Jacobs, R F

    1986-01-01

    Hamsters experimentally inoculated in the inguinal region with Treponema pallidum subsp. endemicum develop considerable pathology at that site. We examined the cell populations from these inguinal lymph nodes to determine their intercellular responses to infection. In vitro, syphilitic-node T cells markedly suppressed C3b receptor-mediated ingestion (C3bMI) in syphilitic macrophages derived from sites both proximal and distal to the inoculation. This activity was more pronounced when node T cells rather than peritoneal T cells were used. When treponemal preparations or live treponemes were added to the coculture system, the suppression was specifically enhanced, whereas the addition of heterologous agents did not promote this effect. Syphilitic macrophages from either compartment cultured alone showed no significant inhibition of C3bMI. In parallel studies on syphilitic macrophages, we observed that the expression of Ia quickly became elevated and was sustained throughout the infection. Moreover, in vitro culturing of the syphilitic-node T cells with these macrophages did not alter this function. These observations suggest that the syphilitic node contains a subpopulation of T cells that can selectively suppress macrophage C3bMI activity and concurrently regulate their cellular response to treponemal infection. PMID:3531014

  20. Modulation of macrophage activation by prostaglandins

    PubMed Central

    Carnuccio, R.; D'Acquisto, F.; Rosa, M. Di

    1996-01-01

    The effect of prostaglandtn E2, iloprost and cAMP on both nitric oxide and tumour necrosis factor-α release in J774 macrophages has been studied. Both prostaglandin E2 and iloprost inhibited, in a concentration-dependent fashion, the lipopolysaccharide-induced generation of nitric oxide and tumour necrosis factor-α. The inhibitory effect of these prostanoids seems to be mediated by an increase of the second messenger cAMP since it was mimicked by dibutyryl cAMP and potentiated by the selective type IV phosphodiesterase inhibitor RO-20-1724. Our results suggest that the inhibition of nitric oxide release by prostaglandin E2 and iloprost in lipopolysaccharide-activated J774 macrophages may be secondary to the inhibition of tumour necrosis factor-α generation, which in turn is likely to be mediated by cAMP. PMID:18475691

  1. Direct imaging of macrophage activation during PDT treatment

    NASA Astrophysics Data System (ADS)

    Song, Sheng; Zhou, Feifan; Chen, Wei R.; Xing, Da

    2012-03-01

    Mounting evidence describes a more complex progress of macrophage activation during photodynamic therapy (PDT), which performing distinct immunological functions and different physiologies on surrounding cells and tissues. Macrophage-targeted PDT has been applied in the selective killing of cells involved in inflammation and tumor. We have previously shown that PDT-mediated tumor cells apoptosis can induce a higher level immune response than necrosis, and enhance the macrophage activation. However, the molecular mechanism of macrophage activation during PDT-induced apoptotic cells (AC) still unclear. Here, we use confocal microscopy to image the phagocytosis of tumor cells by macrophages. We also observed that PDT-treated AC can activate Toll-like receptors (TLRs) which are present on macrophages surface. Besides, the increase in nitric oxide (NO) formation in macrophages was detected in real time by a laser scanning microscopy. This study provided more details for understanding the molecular mechanism of the immune response induced by PDT-treated AC.

  2. Direct imaging of macrophage activation during PDT treatment

    NASA Astrophysics Data System (ADS)

    Song, Sheng; Zhou, Feifan; Chen, Wei R.; Xing, Da

    2011-11-01

    Mounting evidence describes a more complex progress of macrophage activation during photodynamic therapy (PDT), which performing distinct immunological functions and different physiologies on surrounding cells and tissues. Macrophage-targeted PDT has been applied in the selective killing of cells involved in inflammation and tumor. We have previously shown that PDT-mediated tumor cells apoptosis can induce a higher level immune response than necrosis, and enhance the macrophage activation. However, the molecular mechanism of macrophage activation during PDT-induced apoptotic cells (AC) still unclear. Here, we use confocal microscopy to image the phagocytosis of tumor cells by macrophages. We also observed that PDT-treated AC can activate Toll-like receptors (TLRs) which are present on macrophages surface. Besides, the increase in nitric oxide (NO) formation in macrophages was detected in real time by a laser scanning microscopy. This study provided more details for understanding the molecular mechanism of the immune response induced by PDT-treated AC.

  3. The macrophage in HIV-1 infection: from activation to deactivation?

    PubMed

    Herbein, Georges; Varin, Audrey

    2010-04-09

    Macrophages play a crucial role in innate and adaptative immunity in response to microorganisms and are an important cellular target during HIV-1 infection. Recently, the heterogeneity of the macrophage population has been highlighted. Classically activated or type 1 macrophages (M1) induced in particular by IFN-gamma display a pro-inflammatory profile. The alternatively activated or type 2 macrophages (M2) induced by Th-2 cytokines, such as IL-4 and IL-13 express anti-inflammatory and tissue repair properties. Finally IL-10 has been described as the prototypic cytokine involved in the deactivation of macrophages (dM). Since the capacity of macrophages to support productive HIV-1 infection is known to be modulated by cytokines, this review shows how modulation of macrophage activation by cytokines impacts the capacity to support productive HIV-1 infection. Based on the activation status of macrophages we propose a model starting with M1 classically activated macrophages with accelerated formation of viral reservoirs in a context of Th1 and proinflammatory cytokines. Then IL-4/IL-13 alternatively activated M2 macrophages will enter into the game that will stop the expansion of the HIV-1 reservoir. Finally IL-10 deactivation of macrophages will lead to immune failure observed at the very late stages of the HIV-1 disease.

  4. Uptake by mouse peritoneal macrophages of large cholesteryl ester-rich particles isolated from human atherosclerotic lesions.

    PubMed

    Hoff, H F; Clevidence, B A

    1987-06-01

    We have previously shown that a lipoprotein fraction consisting of large cholesteryl ester-rich particles can be isolated from homogenates of human aortic plaques by gel exclusion chromatography. This fraction was recognized by a high-affinity binding site on mouse peritoneal macrophages (MPM) resulting in unregulated uptake, stimulation of cholesterol esterification, and massive accumulation of cholesteryl esters. In this report we have further characterized such a fraction, designated lipid-protein complex (LP), which can be isolated from the void volume fraction of a Bio-Gel A-150m column following chromatography of plaque extracts. LP possessed a mean cholesterol-to-protein ratio of 2.3; it was heterogeneous in size and structure as observed by electron microscopy after negative staining, and it stimulated cholesterol esterification in MPM in a linear fashion over a 48-hr time interval, suggesting that the binding site on MPM recognizing LP was not down-regulated by intracellular cholesterol content. This uptake resulted in the presence of oil red O-positive intracellular droplets and numerous vacuoles containing electron-dense structures, whereas MPM incubated without lipoprotein showed few vacuoles or lipid droplets. Using SDS-PAGE and immunoblot and dot-blot techniques, we found that the major proteins associated with LP were albumin and fibronectin, whereas apoB and apoE were present in lower amounts. These proteins may be responsible for opsonization of LP, making it recognizable to receptors on MPM and facilitating LP uptake by MPM. LP isolated from tissue extracts without homogenization had the same structural and functional characteristics, suggesting that homogenization per se was not responsible for creating a particle that was recognized by MPM. However, homogenization yielded two to three times more LP. MPM uptake of LP derived from lysed foam cells may represent one of the mechanisms by which fatty streak lesions may grow to larger atherosclerotic

  5. Serum from aged F344 rats conditions the activation of young macrophages.

    PubMed

    Gómez, Christian R; Acuña-Castillo, Claudio; Nishimura, Sumiyo; Pérez, Viviana; Escobar, Alejandro; Salazar-Onfray, Flavio; Sabaj, Valeria; Torres, Claudio; Walter, Robin; Sierra, Felipe

    2006-03-01

    There is considerable controversy about the molecular mechanisms responsible for the variations in innate immunity associated with age. While in vivo, aged animals and humans react to an inflammatory signal with an excessive production of pro-inflammatory cytokines, studies in vitro generally show that this response is attenuated in macrophages from old individuals. In an effort to examine possible extrinsic factors that might affect the response of macrophages to lipopolysaccharide (LPS), we have challenged peritoneal macrophages obtained from young rats with sera obtained from rats of different ages. Our results indicate that the serum from aged rats significantly impairs the capacity of young macrophages to induce tumor necrosis factor-alpha (TNF-alpha) production, while at the same time it increases the basal levels of interleukin-6 (IL-6). The effect of serum from aged donors on TNF-alpha secretion requires pre-incubation and is sensitive to heat inactivation. In contrast, the stimulating effect on IL-6 is resistant to heat, and thus should not be due to a protein factor. Therefore, our results indicate that the age-related changes in macrophage activity are not only the consequence of intrinsic changes, but there also appears to be a modulatory effect imparted by the external milieu.

  6. Escherichia coli and Candida albicans Induced Macrophage Extracellular Trap-Like Structures with Limited Microbicidal Activity

    PubMed Central

    Liao, Chengshui; Liu, Xiaolei; Du, Jing; Shi, Haining; Wang, Xuelin; Bai, Xue; Peng, Peng; Yu, Lu; Wang, Feng; Zhao, Ying; Liu, Mingyuan

    2014-01-01

    The formation of extracellular traps (ETs) has recently been recognized as a novel defense mechanism in several types of innate immune cells. It has been suggested that these structures are toxic to microbes and contribute significantly to killing several pathogens. However, the role of ETs formed by macrophages (METs) in defense against microbes remains little known. In this study, we demonstrated that a subset of murine J774A.1 macrophage cell line (8% to 17%) and peritoneal macrophages (8.5% to 15%) form METs-like structures (METs-LS) in response to Escherichia coli and Candida albicans challenge. We found only a portion of murine METs-LS, which are released by dying macrophages, showed detectable killing effects on trapped E. coli but not C. albicans. Fluorescence and scanning electron microscopy analyses revealed that, in vitro, both microorganisms were entrapped in J774A.1 METs-LS composed of DNA and microbicidal proteins such as histone, myeloperoxidase and lysozyme. DNA components of both nucleus and mitochondrion origins were detectable in these structures. Additionally, METs-LS formation occurred independently of ROS produced by NADPH oxidase, and this process did not result in cell lysis. In summary, our results emphasized that microbes induced METs-LS in murine macrophage cells and that the microbicidal activity of these METs-LS differs greatly. We propose the function of METs-LS is to contain invading microbes at the infection site, thereby preventing the systemic diffusion of them, rather than significantly killing them. PMID:24587206

  7. Schisandra polysaccharide evokes immunomodulatory activity through TLR 4-mediated activation of macrophages.

    PubMed

    Zhao, Ting; Feng, Yun; Li, Jing; Mao, Riwen; Zou, Ye; Feng, Weiwei; Zheng, Daheng; Wang, Wei; Chen, Yao; Yang, Liuqing; Wu, Xiangyang

    2014-04-01

    Schisandra chinensis (Turcz.) Baill has been used in traditional Chinese medicine for centuries. Previous studies have shown that Schisandra polysaccharide (SCPP11) has robust antitumor activity in vivo. In this study, the immunomodulatory activity and mechanisms of action of SCPP11 were investigated further to reveal its mechanism of action against tumors. Results showed that SCPP11 increased the thymus and spleen indices, pinocytic activity of peritoneal macrophages, and hemolysin formation in CTX-induced immunosuppressed mice. Moreover, SCPP11 significantly increased immunoglobulin levels, cytokines levels in vivo and induced RAW264.7 cells to secrete cytokines in vitro. RAW264.7 cells pretreated with SCPP11 significantly inhibited the proliferation of HepG-2 cells. In addition, SCPP11 promoted both the expression of iNOS protein and of iNOS and TNF-α mRNA. TLR-4 is a possible receptor for SCPP11-mediated macrophage activation. Therefore, the data suggest that SCPP11 exerted its antitumor activity by improving immune system functions through TLR-4-mediated up-regulation of NO and TNF-α.

  8. THE ENHANCEMENT OF MACROPHAGE BACTERIOSTASIS BY PRODUCTS OF ACTIVATED LYMPHOCYTES

    PubMed Central

    Fowles, Robert E.; Fajardo, Ileana M.; Leibowitch, Jacques L.; David, John R.

    1973-01-01

    It was reported previously that the incubation of normal guinea pig macrophages with partially purified products of activated lymphocytes resulted in altered macrophage function including increased cell adherence to culture vessels, spreading, phagocytosis, and glucose carbon-1 oxidation. Studies reported here demonstrate that such macrophages also exhibit enhanced bacteriostasis. Lymphocytes were stimulated with concanavalin A, the culture supernatant was chromatographed over Sephadex G-100 and the fraction of mol wt 25,000–55,000, rich in lymphocyte mediators, was cultured with normal guinea pig macrophages for 1–3 days. Macrophages incubated with fractions from unstimulated lymphocyte cultures served as controls. The resulting macrophage monolayers were infected with Listeria monocytogenes. Macrophages incubated with mediator-rich fractions exhibited 2- to 10-fold enhanced bacteriostasis compared to controls. Further studies indicate that this enhancement was attributable to intrinsic changes in the macrophages and not simply a consequence of the number of macrophages on the monolayers. The studies support the concept that macrophage bacteriostasis can be enhanced by lymphocyte mediators. However, macrophages, which have been preincubated directly with sensitive lymphocytes and antigen exhibit even greater bacteriostasis and sometimes bactericidal capacity, suggesting that either a labile lymphocyte factor or direct lymphocyte macrophage interaction may also be involved in bactericidal activity. PMID:4200649

  9. Macrophage peroxisome proliferator-activated receptor γ deficiency delays skin wound healing through impairing apoptotic cell clearance in mice.

    PubMed

    Chen, H; Shi, R; Luo, B; Yang, X; Qiu, L; Xiong, J; Jiang, M; Liu, Y; Zhang, Z; Wu, Y

    2015-01-15

    Skin wound macrophages are key regulators of skin repair and their dysfunction causes chronic, non-healing skin wounds. Peroxisome proliferator-activated receptor gamma (PPARγ) regulates pleiotropic functions of macrophages, but its contribution in skin wound healing is poorly defined. We observed that macrophage PPARγ expression was upregulated during skin wound healing. Furthermore, macrophage PPARγ deficiency (PPARγ-knock out (KO)) mice exhibited impaired skin wound healing with reduced collagen deposition, angiogenesis and granulation formation. The tumor necrosis factor alpha (TNF-α) expression in wounds of PPARγ-KO mice was significantly increased and local restoration of TNF-α reversed the healing deficit in PPARγ-KO mice. Wound macrophages produced higher levels of TNF-α in PPARγ-KO mice compared with control. In vitro, the higher production of TNF-α by PPARγ-KO macrophages was associated with impaired apoptotic cell clearance. Correspondingly, increased apoptotic cell accumulation was found in skin wound of PPARγ-KO mice. Mechanically, peritoneal and skin wound macrophages expressed lower levels of various phagocytosis-related molecules. In addition, PPARγ agonist accelerated wound healing and reduced local TNF-α expression and wound apoptotic cells accumulation in wild type but not PPARγ-KO mice. Therefore, PPARγ has a pivotal role in controlling wound macrophage clearance of apoptotic cells to ensure efficient skin wound healing, suggesting a potential new therapeutic target for skin wound healing.

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

    PubMed

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

    2011-06-01

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

  11. D-penicillamine-induced autoimmunity: relationship to macrophage activation.

    PubMed

    Li, Jinze; Uetrecht, Jack P

    2009-09-01

    Idiosyncratic drug reactions represent a serious health problem, and they remain unpredictable largely due to our limited understanding of the mechanisms involved. Penicillamine-induced autoimmunity in Brown Norway (BN) rats represents one model of an idiosyncratic reaction, and this drug can also cause autoimmune reactions in humans. We previously demonstrated that penicillamine binds to aldehydes on the surface of macrophages. There is evidence that an imine bond formed by aldehyde groups on macrophages and amine groups on T cells is one type of interaction between these two cells that is involved in the induction of an immune response. We proposed that the binding of penicillamine with aldehyde groups on macrophages could lead to their activation and in some patients could lead to autoimmunity. In this study, the transcriptome profile of spleen macrophages 6 h after penicillamine treatment was used to detect effects of penicillamine on macrophages with a focus on 20 genes known to be macrophage activation biomarkers. One biological consequence of macrophage activation was investigated by determining mRNA levels for IL-15 and IL-1 beta which are crucial for NK cell activation, as well as levels of mRNA for selected cytokines in spleen NK cells. Up-regulation of the macrophage activating cytokines, IFN-gamma and GM-CSF, and down-regulation of IL-13 indicated activation of NK cells, which suggests a positive feedback loop between macrophages and NK cells. Furthermore, treatment of a murine macrophage cell line, RAW264.7, with penicillamine increased the production of TNF-alpha, IL-6, and IL-23, providing additional evidence that penicillamine activates macrophages. Hydralazine and isoniazid cause a lupus-like syndrome in humans and also bind to aldehyde groups. These drugs were also found to activate RAW264.7 macrophages. Together, these data support the hypothesis that drugs that bind irreversibly with aldehydes lead to macrophage activation, which in some

  12. Comparison of various assays to quantitate macrophage activation by biological response modifiers

    SciTech Connect

    Schultz, R.M.; Nanda, S.; Altom, M.G.

    1984-01-01

    Macrophages treated with various compounds that enhance host antitumor resistance exhibit measurable changes in metabolism, function, and surface antigens. In this study, murine peptone-induced peritoneal macrophages were stimulated in vitro by bacterial lipopolysaccharide (LPS), muramyl dipeptide (MDP), and poly I.poly C. They were subsequently compared in their ability to release superoxide and act as tumoristatic and tumoricidal effector cells. Superoxide generation was assayed by the reduction of ferricytochrome C. All three compounds failed to induce significant O/sub 2/- release, unless the cells were also treated with phorbol myristate acetate (PMA). MDP was most active in potentiating the PMA response. In the tumor growth inhibition assay, cytostatic activity was comparable for all three compounds and did not exceed 32 percent. The combination of subthreshold levels of these compounds and hybridoma-derived MAF acted synergistically to induce potent cytostatic activity. In the chromium release assay, LPS and poly I.poly C rendered macrophages cytolytic for P815 target cells at concentrations greater than or equal to 1 microgram/ml. In contrast, significant cytolysis was observed with MDP only at 100 micrograms/ml. Defining precisely the effect of various biological response modifiers on several parameters of macrophage function may facilitate use of these agents in cancer therapy.

  13. Polarization dictates iron handling by inflammatory and alternatively activated macrophages

    PubMed Central

    Corna, Gianfranca; Campana, Lara; Pignatti, Emanuele; Castiglioni, Alessandra; Tagliafico, Enrico; Bosurgi, Lidia; Campanella, Alessandro; Brunelli, Silvia; Manfredi, Angelo A.; Apostoli, Pietro; Silvestri, Laura; Camaschella, Clara; Rovere-Querini, Patrizia

    2010-01-01

    Background Macrophages play a key role in iron homeostasis. In peripheral tissues, they are known to polarize into classically activated (or M1) macrophages and alternatively activated (or M2) macrophages. Little is known on whether the polarization program influences the ability of macrophages to store or recycle iron and the molecular machinery involved in the processes. Design and Methods Inflammatory/M1 and alternatively activated/M2 macrophages were propagated in vitro from mouse bone-marrow precursors and polarized in the presence of recombinant interferon-γ or interleukin-4. We characterized and compared their ability to handle radioactive iron, the characteristics of the intracellular iron pools and the expression of molecules involved in internalization, storage and export of the metal. Moreover we verified the influence of iron on the relative ability of polarized macrophages to activate antigen-specific T cells. Results M1 macrophages have low iron regulatory protein 1 and 2 binding activity, express high levels of ferritin H, low levels of transferrin receptor 1 and internalize – albeit with low efficiency -iron only when its extracellular concentration is high. In contrast, M2 macrophages have high iron regulatory protein binding activity, express low levels of ferritin H and high levels of transferrin receptor 1. M2 macrophages have a larger intracellular labile iron pool, effectively take up and spontaneously release iron at low concentrations and have limited storage ability. Iron export correlates with the expression of ferroportin, which is higher in M2 macrophages. M1 and M2 cells activate antigen-specific, MHC class II-restricted T cells. In the absence of the metal, only M1 macrophages are effective. Conclusions Cytokines that drive macrophage polarization ultimately control iron handling, leading to the differentiation of macrophages into a subset which has a relatively sealed intracellular iron content (M1) or into a subset endowed with

  14. Cholesteryl ester loading of mouse peritoneal macrophages is associated with changes in the expression or modification of specific cellular proteins, including increase in an alpha-enolase isoform.

    PubMed

    Bottalico, L A; Kendrick, N C; Keller, A; Li, Y; Tabas, I

    1993-02-01

    This report explores the hypothesis that massive cholesteryl ester (CE) accumulation in macrophages, such as that occurring in atheroma foam cells, results in changes in the expression or modification of specific cellular proteins. Two-dimensional (2-D) gel electrophoretic patterns of metabolically labeled cellular proteins from mouse peritoneal macrophages that were loaded with CE (through incubation with acetylated low density lipoprotein [acetyl-LDL] for 4 days) were compared with those of control macrophages. Densitometric analysis of 2-D gel autoradiograms from the cell lysates revealed statistically significant changes in seven cellular proteins (five decreases and two increases). The changes in protein expression (foam cell versus control) ranged from a 458 +/- 164% (p < 0.001) increase to a 35 +/- 34% (p < 0.001) decrease (n = 11). Incubation of macrophages with beta-very low density lipoprotein, which also increased the CE content of macrophages (albeit to a lesser extent than acetyl-LDL), resulted in changes in five of the seven proteins. In contrast, incubation of cells with LDL, fucoidan, or latex beads, none of which caused CE accumulation, did not lead to significant changes in four of these five proteins. One of these four proteins, which increased fourfold to fivefold in foam cells (M(r) = 49,000; isoelectric point of 6.8), was purified by preparative 2-D gel electrophoresis. Internal amino acid sequence of cyanogen bromide fragments of this protein as well as Western blot analysis identified this protein as an isoform of alpha-enolase. The increased expression of this alpha-enolase isoform, which was seen as early as day 2 of acetyl-LDL incubation of the macrophages, was diminished by including an inhibitor of cholesterol esterification during the acetyl-LDL incubation period. In conclusion, macrophage foam cell formation is associated with distinct changes in protein expression, including a marked increase in an isoform of alpha

  15. Bone marrow-derived and peritoneal macrophages have different inflammatory response to oxLDL and M1/M2 marker expression – implications for atherosclerosis research

    PubMed Central

    Bisgaard, Line S.; Mogensen, Christina K.; Rosendahl, Alexander; Cucak, Helena; Nielsen, Lars Bo; Rasmussen, Salka E.; Pedersen, Tanja X.

    2016-01-01

    Macrophages are heterogeneous and can polarize into specific subsets, e.g. pro-inflammatory M1-like and re-modelling M2-like macrophages. To determine if peritoneal macrophages (PEMs) or bone marrow derived macrophages (BMDMs) resembled aortic macrophages from ApoE−/− mice, their M1/M2 phenotype, inflammatory status, and lipid metabolism signatures were compared. oxLDL accumulation was similar in PEMs and BMDMs. On protein expression level, BMDMs showed an M2-like CD206highCD11clow profile, while cholesterol loading led to enhanced CD11c expression and reduced MCP-1 secretion. In contrast, PEMs expressed low levels of CD206 and CD11c, and responded to cholesterol loading by increasing CD11c expression and MCP-1 secretion. mRNA expression of M1/M2 markers was higher in PEMS than BMDMs, while lipid metabolism genes were similarly expressed. Whole aorta flow cytometry showed an accumulation of M2-like CD206highCD11clow macrophages in advanced versus early atherosclerotic disease in ApoE−/− mice. In isolated lesions, mRNA levels of the M2 markers Socs2, CD206, Retnla, and IL4 were downregulated with increasing disease severity. Likewise, mRNA expression of lipid metabolism genes (SREBP2, ACSL1, SRB1, DGAT1, and cpt1a) was decreased in advanced versus early lesions. In conclusion, PEMs and BMDMs are phenotypically distinct and differ from macrophages in lesions with respect to expression of M1/M2 markers and lipid metabolism genes. PMID:27734926

  16. Alternatively activated macrophages in infection and autoimmunity

    PubMed Central

    Fairweather, DeLisa; Cihakova, Daniela

    2009-01-01

    Macrophages are innate immune cells that play an important role in activation of the immune response and wound healing. Pathogens that require T helper-type 2 (Th2) responses for effective clearance, such as parasitic worms, are strong inducers of alternatively activated or M2 macrophages. However, infections such as bacteria and viruses that require Th1-type responses may induce M2 as a strategy to evade the immune system. M2 are particularly efficient at scavenging self tissues following injury through receptors like the mannose receptor and scavenger receptor-A. Thus, M2 may increase autoimmune disease by presenting self tissue to T cells. M2 may also exacerbate immune complex (IC)-mediated pathology and fibrosis, a hallmark of autoimmune disease in women, due to the release of profibrotic factors such as interleukin (IL)-1β, transforming growth factor-β, fibronectin and matrix metalloproteinases. We have found that M2 comprise anywhere from 30% to 70% of the infiltrate during acute viral or experimental autoimmune myocarditis, and shifts in M2 populations correlate with increased IC-deposition, fibrosis and chronic autoimmune pathology. Thus, women may be at an increased risk of M2-mediated autoimmunity due to estrogen’s ability to increase Th2 responses. PMID:19819674

  17. Synergy of anti-CD40, CpG and MPL in activation of mouse macrophages.

    PubMed

    Shi, Yongyu; Felder, Mildred A R; Sondel, Paul M; Rakhmilevich, Alexander L

    2015-08-01

    Activation of macrophages is a prerequisite for their antitumor effects. Several reagents, including agonistic anti-CD40 monoclonal antibody (anti-CD40), CpG oligodeoxynucleotides (CpG) and monophosphoryl lipid A (MPL), can stimulate activation of macrophages. Our previous studies showed synergy between anti-CD40 and CpG and between anti-CD40 and MPL in macrophage activation and antitumor efficacy in mice. In the present study, we asked whether there was synergy among these three reagents. The activation of adherent peritoneal exudate cells (PEC) obtained from mice injected with anti-CD40 and then treated with CpG and/or MPL in vitro was determined by their ability to suppress proliferation of tumor cells and to produce various cytokines and chemokines in vitro. Cell sorting and histology followed by functional testing showed that macrophages were the main cell population in PEC activated by CD40 ligation in vivo. A combination of anti-CD40, CpG or MPL activated PEC to suppress proliferation of B16 cells and produce nitric oxide far greater than the single reagents or any of the double combinations of these reagents. In addition, the combination of all three reagents activated PEC to secrete IL-12, IFN-γ and MCP-1 to a greater degree than any single reagent or any two combined reagents. These results demonstrate that macrophages can be synergistically activated by anti-CD40, CpG and MPL, suggesting that this novel combined approach might be further investigated as potential cancer therapy.

  18. Modulation of macrophage activation and programming in immunity.

    PubMed

    Liu, Guangwei; Yang, Hui

    2013-03-01

    Macrophages are central mediators of the immune, contributing both to the initiation and the resolution of inflammation. The concept of macrophage activation and program has stimulated interest in its definition, and functional significance in homeostasis and diseases. It has been known that macrophages could be differently activated and programmed into different functional subtypes in response to different types of antigen stumuli or different kinds of cytokines present in the microenvironment and could thus profoundly influence immune responses, but little is known about the state and exact regulatory mechanism of macrophage activation and program from cell or molecular signaling level in immunity. In this review, we summarize the recent finding regarding the regulatory mechanism of macrophage activation and program toward M1 and M2, especially on M2 macrophages.

  19. Lysis of herpesvirus-infected cells by macrophages activated with free or liposome-encapsulated lymphokine produced by a murine T cell hybridoma.

    PubMed Central

    Koff, W C; Showalter, S D; Seniff, D A; Hampar, B

    1983-01-01

    Thioglycolate-induced mouse peritoneal macrophages were activated in vitro by the lymphokine designated macrophage-activating factor (MAF) produced by a murine T cell hybridoma to lyse herpes simplex virus type 2 (HSV-2)-infected murine target cells. Comparison of uninfected BALB/c 10E2 cells with HSV-2-infected 10E2 cells showed that macrophages activated with MAF selectively destroyed HSV-2-infected cells and left uninfected cells unharmed, as measured by an 18-h 51Cr-release assay. In contrast, macrophages treated with medium were as efficient as MAF-activated macrophages in suppressing the production of HSV-2 from virus-infected cells. These findings suggest that macrophages must attain an activated state to lyse HSV-2-infected cells. Finally, incubation of macrophages with liposomes containing MAF was shown to be a highly efficient method for activation of macrophages against HSV-2 infected cells. The ability to selectively destroy herpesvirus-infected cells in vitro by macrophages activated with liposome-encapsulated MAF suggests that the therapeutic efficacy of this treatment in vivo should be evaluated. PMID:6358037

  20. The predominance of alternatively activated macrophages following challenge with cell wall peptide-polysaccharide after prior infection with Sporothrix schenckii.

    PubMed

    Alegranci, Pamela; de Abreu Ribeiro, Livia Carolina; Ferreira, Lucas Souza; Negrini, Thais de Cássia; Maia, Danielle Cardoso Geraldo; Tansini, Aline; Gonçalves, Amanda Costa; Placeres, Marisa Campos Polesi; Carlos, Iracilda Zeppone

    2013-08-01

    Sporotrichosis is a subcutaneous mycosis that is caused by the dimorphic fungus Sporothrix schenckii. This disease generally occurs within the skin and subcutaneous tissues, causing lesions that can spread through adjacent lymphatic vessels and sometimes leading to systemic diseases in immunocompromised patients. Macrophages are crucial for proper immune responses against a variety of pathogens. Furthermore, macrophages can play different roles in response to different microorganisms and forms of activation, and they can be divided into "classic" or "alternatively" activated populations, as also known as M1 and M2 macrophages. M1 cells can lead to tissue injury and contribute to pathogenesis, whereas M2 cells promote angiogenesis, tissue remodeling, and repair. The aim of this study was to investigate the roles of M1 and M2 macrophages in a sporotrichosis model. Toward this end, we performed phenotyping of peritoneal exudate cells and evaluated the concomitant production of several immunomediators, including IL-12, IL-10, TGF-β, nitric oxide, and arginase-I activity, which were stimulated ex vivo with cell wall peptide-polysaccharide. Our results showed the predominance of the M2 macrophage population, indicated by peaks of arginase-I activity as well as IL-10 and TGF-β production during the 6th and 8th weeks after infection. These results were consistent with cellular phenotyping that revealed increases in CD206-positive cells over this period. This is the first report of the participation of M2 macrophages in sporotrichosis infections.

  1. Inhibition of Chlamydia psittaci in oxidatively active thioglycolate-elicited macrophages: distinction between lymphokine-mediated oxygen-dependent and oxygen-independent macrophage activation.

    PubMed Central

    Byrne, G I; Faubion, C L

    1983-01-01

    Immune sensitization of spleen cells was required to generate lymphokines (LK) that activated thioglycolate-elicited peritoneal macrophages (thio MACs) to respond via both oxygen-dependent and oxygen-independent systems. LK produced by incubating spleen cells from immunized A/J and LAF mice with concanavalin A stimulated a response by thio MACs to phorbol-12-myristate-13-acetate (PMA)-induced chemiluminescence and activated these cells to inhibit intracellular Chlamydia psittaci replication. Concanavalin A-incubated spleen cell preparations from unimmunized animals stimulated neither PMA-induced chemiluminescence nor antichlamydial activity. Activated thio MACs demonstrated a rapid chemiluminescence response to the intracellular protozoan Toxoplasma gondii, but C. psittaci did not induce chemiluminescence in LK-activated thio MACs, although cells exposed to C. psittaci retained their responsiveness to PMA-induced chemiluminescence. The PMA-induced response was inhibited by the addition of exogenous superoxide dismutase and catalase and was therefore related to the production of superoxide anion (O2 . -) and H2O2 by these cells. LK preparations incubated at 56 degrees C before macrophage treatment retained antichlamydial activity, but heated preparations no longer stimulated thio MACs to respond in the chemiluminescence assay. These data provide evidence that macrophage oxygen-dependent and oxygen-independent systems are simultaneously activated by LK, and these preparations comprise at least two distinct activities. The portion responsible for activating oxygen-dependent systems (PMA-induced chemiluminescence) is heat labile, whereas the portion responsible for activating oxygen-independent systems is heat stable. It is the latter system that results in restriction of chlamydial growth and in vitro parasite persistence. PMID:6840848

  2. Titanium particles that have undergone phagocytosis by macrophages lose the ability to activate other macrophages.

    PubMed

    Xing, Zhiqing; Schwab, Luciana P; Alley, Carie F; Hasty, Karen A; Smith, Richard A

    2008-04-01

    Titanium particles derived from the wear of the orthopaedic implant surfaces can activate macrophages to secrete cytokines and stimulate osteoclastic bone resorption, causing osteolysis around orthopaedic implants. However, what happens to the titanium particles after being phagocytosed by macrophages is not known. We prepared titanium particles (as received, clean, and LPS-coated), and exposed them to macrophages in culture. Free particles were washed away after 24 h and the intracellular particles were kept in culture for additional 48 h until being harvested by lysing the cells. Particles that had been cell treated or noncell treated were examined by scanning electronic microscopy to analyze the shape, size, and concentration of the particles. The cell treated and noncell treated particles were exposed to macrophages in culture with a particle to cell ratio of 300:1. After 18 h, the levels of TNF-alpha in culture medium and the viability of the cells were examined. Clean particles did not stimulate TNF-alpha secretion by macrophages, while LPS-coated particles dramatically increased that response. Phagocytosis by macrophages did not change the shape and size of the particles, but depleted the ability of the particles to stimulate TNF-alpha secretion by macrophages. This indicates that macrophages are capable of rendering titanium particles inactive without degrading the particles, possibly by altering the surface chemistry of the particles.

  3. Platelet activating factor raises intracellular calcium ion concentration in macrophages

    PubMed Central

    1986-01-01

    Peritoneal cells from thioglycollate-stimulated mice were allowed to adhere to coverglasses for 2 h to give a dense monolayer of adherent cells greater than 95% of which were macrophages. After incubation with the tetra-acetoxymethyl ester of quin2, coverglasses were rinsed with Ca2+-free saline, oriented at a 45 degree angle in square cuvettes containing a magnetically driven stir bar, and analyzed for changes in quin2 fluorescence in a spectrofluorimeter. Such fluorescence, taken as an indication of intracellular calcium ion concentration ([Ca2+]i), increased as exogenous calcium ion concentration ([Ca2+]o) was raised to 1 mM. At [Ca2+]o approximately equal to 10 microM, [Ca2+]i = 72 +/- 14 nM (n = 26); at [Ca2+]o = 1 mM, [Ca2+]i = 140-220 nM, levels not increased by N, N, N', N'-tetrakis (2-pyridylmethyl) ethylenediamine, a membrane-permeant chelator of heavy metals than can quench quin2. Addition of mouse alpha + beta fibroblast interferon, lipopolysaccharide, thrombin, collagen, vasopressin, ADP, compound 48/80, or U46619 did not change [Ca2+]i. However, addition of platelet activating factor (PAF) (2-20 ng/ml) raised [Ca2+]i by 480 nM within 1 min if [Ca2+]o = 1 mM. In the presence of 5 mM EGTA, PAF raised [Ca2+]i by 25 nM. This suggests that PAF causes influx of exogenous Ca2+, as well as releasing some Ca2+ from intracellular stores. Consistent with these results, when PAF was added to 1 mM Ca2+ in the presence of 100 microM Cd2+ or Mn2+ to block Ca2+ influx, [Ca2+]i increased by only intermediate amounts; at the times of such dampened peak response, [Ca2+]i could be raised within 1 min to normal PAF-stimulated levels by chelation of the exogenous heavy metals with diethylenetriaminepentaacetic acid. Normal PAF responses were observed in the presence of indomethacin. The lowest dose of PAF observed to raise [Ca2+]i was 0.1 ng/ml. Response of [Ca2+]i to 2-20 ng/ml PAF was transient, and second applications had no effect. The PAF response also was seen in

  4. Activation of macrophages and lymphocytes by methylglyoxal against tumor cells in the host.

    PubMed

    Bhattacharyya, Nivedita; Pal, Aparajita; Patra, Subrata; Haldar, Arun Kumar; Roy, Syamal; Ray, Manju

    2008-11-01

    Methylglyoxal is a normal metabolite and has the potential to affect a wide variety of cellular processes. In particular, it can act selectively against malignant cells. The study described herein was to investigate whether methylglyoxal can enhance the non-specific immunity of the host against tumor cells. Methylglyoxal increased the number of macrophages in the peritoneal cavity of both normal and tumor-bearing mice. It also elevated the phagocytic capacity of macrophages in both these groups of animals. This activation of macrophages was brought about by increased production of Reactive Oxygen Intermediates (ROIs) and Reactive Nitrogen Intermediates (RNIs). The possible mechanism for the production of ROIs and RNIs can be attributed to stimulation of the respiratory burst enzyme NADPH oxidase and iNOS, respectively. IFN-gamma, which is a regulatory molecule of iNOS pathway also showed an elevated level by methylglyoxal. TNF-alpha, which is an important cytokine for oxygen independent killing by macrophage also increased by methylglyoxal in both tumor-bearing and non tumor-bearing animals. Methylglyoxal also played a role in the proliferation and cytotoxicity of splenic lymphocytes. In short, it can be concluded that methylglyoxal profoundly stimulates the immune system against tumor cells.

  5. Phosphodiesterase 4B negatively regulates endotoxin-activated interleukin-1 receptor antagonist responses in macrophages

    PubMed Central

    Yang, Jing-Xing; Hsieh, Kou-Chou; Chen, Yi-Ling; Lee, Chien-Kuo; Conti, Marco; Chuang, Tsung-Hsien; Wu, Chin-Pyng; Jin, S.-L. Catherine

    2017-01-01

    Activation of TLR4 by lipopolysaccharide (LPS) induces both pro-inflammatory and anti-inflammatory cytokine production in macrophages. Type 4 phosphodiesterases (PDE4) are key cAMP-hydrolyzing enzymes, and PDE4 inhibitors are considered as immunosuppressors to various inflammatory responses. We demonstrate here that PDE4 inhibitors enhance the anti-inflammatory cytokine interleukin-1 receptor antagonist (IL-1Ra) secretion in LPS-activated mouse peritoneal macrophages, and this response was regulated at the transcriptional level rather than an increased IL-1Ra mRNA stability. Studies with PDE4-deficient macrophages revealed that the IL-1Ra upregulation elicited by LPS alone is PKA-independent, whereas the rolipram-enhanced response was mediated by inhibition of only PDE4B, one of the three PDE4 isoforms expressed in macrophages, and it requires PKA but not Epac activity. However, both pathways activate CREB to induce IL-1Ra expression. PDE4B ablation also promoted STAT3 phosphorylation (Tyr705) to LPS stimulation, but this STAT3 activation is not entirely responsible for the IL-1Ra upregulation in PDE4B-deficient macrophages. In a model of LPS-induced sepsis, only PDE4B-deficient mice displayed an increased circulating IL-1Ra, suggesting a protective role of PDE4B inactivation in vivo. These findings demonstrate that PDE4B negatively modulates anti-inflammatory cytokine expression in innate immune cells, and selectively targeting PDE4B should retain the therapeutic benefits of nonselective PDE4 inhibitors. PMID:28383060

  6. Killing of Aspergillus spores depends on the anatomical source of the macrophage.

    PubMed Central

    Schaffner, A; Douglas, H; Braude, A I; Davis, C E

    1983-01-01

    To resolve the controversy over the capacity of macrophages to kill or inhibit germination of Aspergillus spores, we compared this function in peritoneal and alveolar macrophages. Alveolar macrophages from rabbits killed 82 to 90% and completely digested 72 to 82% of spores of Aspergillus fumigatus in 30 h. In contrast, peritoneal macrophages could not even inhibit the germination of ingested spores; more than 85% transformed into mycelia within 24 h. Killing by alveolar macrophages was delayed for 3 to 6 h after phagocytosis and was independent of oxidative killing mechanisms and immune activation. The ability of alveolar macrophages to kill Aspergillus spores without modulation by T lymphocytes or the generation of oxygen intermediates points out that concepts built on studies of peritoneal macrophages may be misleading and underscores the importance of studying the role of macrophages in immunity with cells from the appropriate anatomical site. Images PMID:6642661

  7. Influence of exercise on NA- and Hsp72-induced release of IFNγ by the peritoneal suspension of macrophages and lymphocytes from genetically obese Zucker rats.

    PubMed

    Martín-Cordero, L; García, J J; Hinchado, M D; Bote, E; Ortega, E

    2013-03-01

    Regular physical exercise is recognized as a nonpharmacological therapeutic strategy in the treatment of metabolic syndrome, and has been proposed for improving obesity, diabetic status, insulin resistance, and immune response. The aim of the present study was to evaluate the effect of a regular exercise program (treadmill running, 5 days/week for 14 weeks at 35 cm/s for 35 min in the last month) on the release of the pro-inflammatory cytokine interferon gamma (IFNγ) by peritoneal cells (macrophages and lymphocytes) from obese Zucker rats (fa/fa) in response to noradrenaline (NA) and heat shock proteins of 72 kDa (Hsp72), and the possible adaptation due to training for a bout acute exercise (a single session of 25-35 min at 35 cm/s). In healthy (lean Fa/fa) and obese animals, peritoneal cells released greater concentrations of IFNγ in response to Hsp72 and lower concentrations in response to NA. The regular exercise training protocol, evaluated in the obese animals, produced a clear change in the regulation of the release of IFNγ. Peritoneal immune cells from trained animals released more IFNγ in response to NA, but there was a reduction in the release of IFNγ in response to Hsp72. In the obese animals, regular exercise caused a change in the inhibitory effect of NA (which now becomes stimulatory) and the stimulatory effect of Hsp72e (which now becomes inhibitory) in relation to the release of IFNγ. This reflects that Hsp72, induced by the prior release of NA following exercise-induced stress, plays a role in the homeostatic balance of release of IFNγ by peritoneal immune cells in obese animals during exercise.

  8. Cellular and Molecular Mechanisms Underpinning Macrophage Activation during Remyelination

    PubMed Central

    Lloyd, Amy F.; Miron, Veronique E.

    2016-01-01

    Remyelination is an example of central nervous system (CNS) regeneration, whereby myelin is restored around demyelinated axons, re-establishing saltatory conduction and trophic/metabolic support. In progressive multiple sclerosis, remyelination is limited or fails altogether which is considered to contribute to axonal damage/loss and consequent disability. Macrophages have critical roles in both CNS damage and regeneration, such as remyelination. This diverse range in functions reflects the ability of macrophages to acquire tissue microenvironment-specific activation states. This activation is dynamically regulated during efficient regeneration, with a switch from pro-inflammatory to inflammation-resolution/pro-regenerative phenotypes. Although, some molecules and pathways have been implicated in the dynamic activation of macrophages, such as NFκB, the cellular and molecular mechanisms underpinning plasticity of macrophage activation are unclear. Identifying mechanisms regulating macrophage activation to pro-regenerative phenotypes may lead to novel therapeutic strategies to promote remyelination in multiple sclerosis. PMID:27446913

  9. Macrophage Bactericidal Activities against Staphylococcus aureus Are Enhanced In Vivo by Selenium Supplementation in a Dose-Dependent Manner

    PubMed Central

    Aribi, Mourad; Meziane, Warda; Habi, Salim; Boulatika, Yasser

    2015-01-01

    Background Dietary selenium is of fundamental importance to maintain optimal immune function and enhance immunity during infection. To this end, we examined the effect of selenium on macrophage bactericidal activities against Staphylococcus aureus. Methods Assays were performed in golden Syrian hamsters and peritoneal macrophages cultured with S. aureus and different concentrations of selenium. Results Infected and selenium-supplemented animals have significantly decreased levels of serum nitric oxide (NO) production when compared with infected but non-selenium-supplemented animals at day 7 post-infection (p < 0.05). A low dose of 5 ng/mL selenium induced a significant decrease in macrophage NO production, but significant increase in hydrogen peroxide (H2O2) levels (respectively, p = 0.009, p < 0.001). The NO production and H2O2 levels were significantly increased with increasing concentrations of selenium; the optimal macrophage activity levels were reached at 20 ng/mL. The concentration of 5 ng/mL of selenium induced a significant decrease in the bacterial arginase activity but a significant increase in the macrophage arginase activity. The dose of 20 ng/mL selenium induced a significant decrease of bacterial growth (p < 0.0001) and a significant increase in macrophage phagocytic activity, NO production/arginase balance and S. aureus killing (for all comparisons, p < 0.001). Conclusions Selenium acts in a dose-dependent manner on macrophage activation, phagocytosis and bacterial killing suggesting that inadequate doses may cause a loss of macrophage bactericidal activities and that selenium supplementation could enhance the in vivo control of immune response to S. aureus. PMID:26340099

  10. Tumor cell alpha-N-acetylgalactosaminidase activity and its involvement in GcMAF-related macrophage activation.

    PubMed

    Mohamad, Saharuddin B; Nagasawa, Hideko; Uto, Yoshihiro; Hori, Hitoshi

    2002-05-01

    Alpha-N-acetyl galactosaminidase (alpha-NaGalase) has been reported to accumulate in serum of cancer patients and be responsible for deglycosylation of Gc protein, which is a precursor of GcMAF-mediated macrophage activation cascade, finally leading to immunosuppression in advanced cancer patients. We studied the biochemical characterization of alpha-NaGalase from several human tumor cell lines. We also examined its effect on the potency of GcMAF to activate mouse peritoneal macrophage to produce superoxide in GcMAF-mediated macrophage activation cascade. The specific activity of alpha-NaGalases from human colon tumor cell line HCT116, human hepatoma cell line HepG2, and normal human liver cells (Chang liver cell line) were evaluated using two types of substrates; GalNAc-alpha-PNP (exo-type substrate) and Gal-beta-GalNAc-alpha-PNP (endo-type substrate). Tumor-derived alpha-NaGalase having higher activity than normal alpha-NaGalase, had higher substrate specificity to the exo-type substrate than to the endo-type substrate, and still maintained its activity at pH 7. GcMAF enhance superoxide production in mouse macrophage, and pre-treatment of GcMAF with tumor cell lysate reduce the activity. We conclude that tumor-derived alpha-NaGalase is different in biochemical characterization compared to normal alpha-NaGalase from normal Chang liver cells. In addition, tumor cell-derived alpha-NaGalase decreases the potency of GcMAF on macrophage activation.

  11. Exopolysaccharide from Trichoderma pseudokoningii induces macrophage activation.

    PubMed

    Wang, Guodong; Zhu, Lei; Yu, Bo; Chen, Ke; Liu, Bo; Liu, Jun; Qin, Guozheng; Liu, Chunyan; Liu, Huixia; Chen, Kaoshan

    2016-09-20

    In this study, we evaluated the immunomodulatory activity of an exopolysaccharide (EPS) derived from Trichoderma pseudokoningii and investigated the molecular mechanism of EPS-mediated activation of macrophages. Results revealed that EPS could significantly induce the production of nitric oxide (NO), tumor necrosis factor (TNF)-α and interleukin (IL)-1β and enhance phagocytic activity in RAW 264.7 cells. Immunofluorescence staining indicated that EPS promoted the nuclear translocation of nuclear factor (NF)-κB p65 subunit. Western blot analysis showed that EPS increased the expression of inducible nitric oxide synthase (iNOS) protein, the degradation of IκB-α and the phosphorylation of mitogen-activated protein kinases (MAPKs). Furthermore, pretreatment of RAW 264.7 cells with specific inhibitors of NF-κB and MAPKs significantly attenuated EPS-induced TNF-α and IL-1β production. EPS also induced the inhibition of cytokine secretion by special antibodies against Toll-like receptor-4 (TLR4) and Dectin-1. These data suggest that EPS from Trichoderma pseudokoningii activates RAW 264.7 cells through NF-κB and MAPKs signaling pathways via TLR4 and Dectin-1.

  12. CCL2 Mediates Neuron-Macrophage Interactions to Drive Proregenerative Macrophage Activation Following Preconditioning Injury.

    PubMed

    Kwon, Min Jung; Shin, Hae Young; Cui, Yuexian; Kim, Hyosil; Thi, Anh Hong Le; Choi, Jun Young; Kim, Eun Young; Hwang, Dong Hoon; Kim, Byung Gon

    2015-12-02

    CNS neurons in adult mammals do not spontaneously regenerate axons after spinal cord injury. Preconditioning peripheral nerve injury allows the dorsal root ganglia (DRG) sensory axons to regenerate beyond the injury site by promoting expression of regeneration-associated genes. We have previously shown that peripheral nerve injury increases the number of macrophages in the DRGs and that the activated macrophages are critical to the enhancement of intrinsic regeneration capacity. The present study identifies a novel chemokine signal mediated by CCL2 that links regenerating neurons with proregenerative macrophage activation. Neutralization of CCL2 abolished the neurite outgrowth activity of conditioned medium obtained from neuron-macrophage cocultures treated with cAMP. The neuron-macrophage interactions that produced outgrowth-promoting conditioned medium required CCL2 in neurons and CCR2/CCR4 in macrophages. The conditioning effects were abolished in CCL2-deficient mice at 3 and 7 d after sciatic nerve injury, but CCL2 was dispensable for the initial growth response and upregulation of GAP-43 at the 1 d time point. Intraganglionic injection of CCL2 mimicked conditioning injury by mobilizing M2-like macrophages. Finally, overexpression of CCL2 in DRGs promoted sensory axon regeneration in a rat spinal cord injury model without harmful side effects. Our data suggest that CCL2-mediated neuron-macrophage interaction plays a critical role for amplification and maintenance of enhanced regenerative capacity by preconditioning peripheral nerve injury. Manipulation of chemokine signaling mediating neuron-macrophage interactions may represent a novel therapeutic approach to promote axon regeneration after CNS injury.

  13. Mutation of neutralizing/antibody-dependent enhancing epitope on spike protein and 7b gene of feline infectious peritonitis virus: influences of viral replication in monocytes/macrophages and virulence in cats.

    PubMed

    Takano, Tomomi; Tomiyama, Yoshika; Katoh, Yasuichiroh; Nakamura, Michiyo; Satoh, Ryoichi; Hohdatsu, Tsutomu

    2011-03-01

    We previously prepared neutralizing monoclonal antibody (MAb)-resistant (mar) mutant viruses using a laboratory strain feline infectious peritonitis virus (FIPV) 79-1146 (Kida et al., 1999). Mar mutant viruses are mutated several amino acids of the neutralizing epitope of Spike protein, compared with the parent strain, FIPV 79-1146. We clarified that MAb used to prepare mar mutant viruses also lost its activity to enhance homologous mar mutant viruses, strongly suggesting that neutralizing and antibody-dependent enhancing epitopes are present in the same region in the strain FIPV 79-1146. We also discovered that amino acid mutation in the neutralizing epitope reduced viral replication in monocytes/macrophages. We also demonstrated that the mutation or deletion of two nucleotides in 7b gene abrogate the virulence of strain FIPV 79-1146.

  14. Receptors for oxidized low-density lipoprotein on elicited mouse peritoneal macrophages can recognize both the modified lipid moieties and the modified protein moieties: Implications with respect to macrophage recognition of apoptotic cells

    PubMed Central

    Bird, David A.; Gillotte, Kristin L.; Hörkkö, Sohvi; Friedman, Peter; Dennis, Edward A.; Witztum, Joseph L.; Steinberg, Daniel

    1999-01-01

    It has been shown previously that the binding of oxidized low-density lipoprotein (OxLDL) to resident mouse peritoneal macrophages can be inhibited (up to 70%) by the apoprotein B (apoB) isolated from OxLDL, suggesting that macrophage recognition of OxLDL is primarily dependent on its modified protein moiety. However, recent experiments have demonstrated that the lipids isolated from OxLDL and reconstituted into a microemulsion can also strongly inhibit uptake of OxLDL (up to 80%). The present studies show that lipid microemulsions prepared from OxLDL bind to thioglycollate-elicited macrophages at 4°C in a saturable fashion and inhibit the binding of intact OxLDL and also of the apoB from OxLDL. Reciprocally, the binding of the OxLDL-lipid microemulsions was strongly inhibited by intact OxLDL. A conjugate of synthetic 1-palmitoyl 2(5-oxovaleroyl) phosphatidylcholine (an oxidation product of 1-palmitoyl 2-arachidonoyl phosphatidylcholine) with serum albumin, shown previously to inhibit macrophage binding of intact OxLDL, also inhibited the binding of both the apoprotein and the lipid microemulsions prepared from OxLDL. Finally, a monoclonal antibody against oxidized phospholipids, one that inhibits binding of intact OxLDL to macrophages, also inhibited the binding of both the resolubilized apoB and the lipid microemulsions prepared from OxLDL. These studies support the conclusions that: (i) at least some of the macrophage receptors for oxidized LDL can recognize both the lipid and the protein moieties; and (ii) oxidized phospholipids, in the lipid phase of the lipoprotein and/or covalently linked to the apoB of OxLDL, likely play a role in that recognition. PMID:10339590

  15. Control of tumor-associated macrophage alternative activation by MIF

    PubMed Central

    Yaddanapudi, Kavitha; Putty, Kalyani; Rendon, Beatriz E.; Lamont, Gwyneth J.; Faughn, Jonathan D.; Satoskar, Abhay; Lasnik, Amanda; Eaton, John W.; Mitchell, Robert A.

    2013-01-01

    Tumor stromal alternatively activated macrophages are important determinants of anti-tumor T lymphocyte responses, intratumoral neovascularization and metastatic dissemination. Our recent efforts to investigate the mechanism of macrophage migration inhibitory factor (MIF) in antagonizing anti-melanoma immune responses reveal that macrophage-derived MIF participates in macrophage alternative activation in melanoma-bearing mice. Both peripheral and tumor-associated macrophages (TAMs) isolated from melanoma bearing MIF-deficient mice display elevated pro-inflammatory cytokine expression and reduced anti-inflammatory, immunosuppressive and pro-angiogenic gene products compared to macrophages from tumor bearing MIF wildtype mice. Moreover, TAMs and myeloid-derived suppressor cells (MDSCs) from MIF-deficient mice exhibit reduced T lymphocyte immunosuppressive activities than do those from their wildtype littermates. Corresponding with reduced tumor immunosuppression and neoangiogenic potential by TAMs, MIF-deficiency confers protection against transplantable subcutaneous melanoma outgrowth and melanoma lung metastatic colonization. Finally, we report for the first time that our previously discovered MIF small molecule antagonist, 4-iodo-6-phenylpyrimidine (4-IPP), recapitulates MIF-deficiency in vitro and in vivo and attenuates tumor polarized macrophage alternative activation, immunosuppression, neoangiogenesis and melanoma tumor outgrowth. These studies describe an important functional contribution by MIF to tumor-associated macrophage alternative activation and provide justification for immunotherapeutic targeting of MIF in melanoma patients. PMID:23390297

  16. "In vivo" murine macrophages activation by a dichloromethane extract of Tilia x viridis.

    PubMed

    Davicino, Roberto; Micucci, Patricia; Zettler, Gabriela; Ferraro, Graciela; Anesini, Claudia

    2010-09-01

    Macrophages are involved in the host defense against infectious pathogens and tumors. Tilia species have been used in folk medicine for the treatment of infectious diseases, previously it was demonstrated that a dichloromethane (DM) extract possess antiproliferative action "in vitro" on a lymphoma cell line. The aim of this work was to study the "in vivo" effect of DM extract upon mice peritoneal macrophages. DM extract-activated macrophages phagocytosis through hydrogen peroxide (H(2)O(2)) and nitric oxide (NO) production (phagocytosis (%): basal 16.93 +/- 0.18, DM extract 25.93 +/- 2.8; H(2)O(2) (M): basal 0.0022 +/- 0.00016, DM extract 0.0036 +/- 0.0005; NO (mM): basal 0.0052 +/- 0.0007, DM extract 0.0099 +/- 0.0004). These actions were mediated by cell superoxide dismutase activation. On the other hand, DM extract decreased tumor necrosis factor alpha but increased interleukin-10 in serum. These results suggest that the modulation activity exerted by the extract on immune system cells could be an important mechanism to acquire resistance to tumors and infectious diseases.

  17. Sodium-activated macrophages: the salt mine expands.

    PubMed

    Lucca, Liliana E; Hafler, David A

    2015-08-01

    High sodium consumption has been raising interest as a putative environmental factor linking Western lifestyle to the growing epidemic of autoimmune and inflammatory diseases. Now Zhang and colleagues show that high sodium drives macrophage to acquire a new proinflammatory effector phenotype with a distinct signature, paving the path to assess the role of salt-activated macrophages in human disease.

  18. EGFR regulates macrophage activation and function in bacterial infection.

    PubMed

    Hardbower, Dana M; Singh, Kshipra; Asim, Mohammad; Verriere, Thomas G; Olivares-Villagómez, Danyvid; Barry, Daniel P; Allaman, Margaret M; Washington, M Kay; Peek, Richard M; Piazuelo, M Blanca; Wilson, Keith T

    2016-09-01

    EGFR signaling regulates macrophage function, but its role in bacterial infection has not been investigated. Here, we assessed the role of macrophage EGFR signaling during infection with Helicobacter pylori, a bacterial pathogen that causes persistent inflammation and gastric cancer. EGFR was phosphorylated in murine and human macrophages during H. pylori infection. In human gastric tissues, elevated levels of phosphorylated EGFR were observed throughout the histologic cascade from gastritis to carcinoma. Deleting Egfr in myeloid cells attenuated gastritis and increased H. pylori burden in infected mice. EGFR deficiency also led to a global defect in macrophage activation that was associated with decreased cytokine, chemokine, and NO production. We observed similar alterations in macrophage activation and disease phenotype in the Citrobacter rodentium model of murine infectious colitis. Mechanistically, EGFR signaling activated NF-κB and MAPK1/3 pathways to induce cytokine production and macrophage activation. Although deletion of Egfr had no effect on DC function, EGFR-deficient macrophages displayed impaired Th1 and Th17 adaptive immune responses to H. pylori, which contributed to decreased chronic inflammation in infected mice. Together, these results indicate that EGFR signaling is central to macrophage function in response to enteric bacterial pathogens and is a potential therapeutic target for infection-induced inflammation and associated carcinogenesis.

  19. An Analog of the Antimicrobial Peptide CopA5 Inhibits Lipopolysaccharide-Induced Macrophage Activation.

    PubMed

    Yoon, I Na; Hong, Ji; Zhang, Peng; Hwang, Jae Sam; Kim, Ho

    2017-02-28

    We previously reported that the CopA3 peptide (LLCIALRKK, D-form) originally isolated from the Korean dung beetle has antimicrobial and immunosuppressive effects. However, the high cost of producing the synthetic peptide, especially the D-form, has limited the development of CopA3 for therapeutic purposes. Here, we investigated whether the CopA3 deletion derivative, CopA5, which is composed of only five amino acids (LLCIA) and has the L-form structure, could inhibit the lipopolysaccharide (LPS)-induced activation of macrophages. Peritoneal exudate macrophages (PEM) were isolated from mice and exposed to LPS in the presence or absence of CopA5, and biomarkers of macrophage activation were measured. Our results revealed that LPS-induced nitric oxide (NO) production, tumor necrosis factor (TNF)-α secretion, and phagocytic activity of PEM were significantly inhibited by CopA5 treatment. Similar to CopA3, the structurally modified CopA5 peptide had no cell toxicity (as assessed by measurement of cell viability loss and apoptosis) in PEM. Moreover, the LPS-induced upregulation of the activating phosphorylation of signal transducer and activator of transcription 1 (STAT1) was markedly inhibited by CopA5 treatment. These results suggest that, similar to CopA3, CopA5 inhibits macrophage activation by inhibiting STAT1 phosphorylation and blocking the release of NO and TNF-α. CopA5 may therefore prove therapeutically useful in the realm of immune suppression.

  20. Retinal Pigment Epithelial Cells Suppress Phagolysosome Activation in Macrophages

    PubMed Central

    Wang, Eric; Choe, Yoona; Ng, Tat Fong; Taylor, Andrew W.

    2017-01-01

    Purpose The eye is an immune-privileged microenvironment that has adapted several mechanisms of immune regulation to prevent inflammation. One of these potential mechanisms is retinal pigment epithelial cells (RPE) altering phagocytosis in macrophages. Methods The conditioned media of RPE eyecups from eyes of healthy mice and mice with experimental autoimmune uveitis (EAU) were used to treat primary macrophage phagocytizing pHrodo bacterial bioparticles. In addition, the neuropeptides were depleted from the conditioned media of healthy RPE eyecups and used to treat phagocytizing macrophages. The conditioned media from healthy and EAU RPE eyecups were assayed for IL-6, and IL-6 was added to the healthy conditioned media, and neutralized in the EAU conditioned media. The macrophages were treated with the conditioned media and assayed for fluorescence. The macrophages were imaged, and the fluorescence intensity, relative to active phagolysosomes, was measured. Also, the macrophages were assayed using fluorescent viability dye staining. Results The conditioned media from healthy, but not from EAU RPE eyecups suppressed phagolysosome activation. Depletion of the neuropeptides alpha-melanocyte–stimulating hormone and neuropeptide Y from the healthy RPE eyecup conditioned media resulted in macrophage death. In the EAU RPE eyecup conditioned media was 0.96 ± 0.18 ng/mL of IL-6, and when neutralized the conditioned media suppressed phagolysosome activation. Conclusions The healthy RPE through soluble molecules, including alpha-melanocyte–stimulating hormone and neuropeptide Y, suppresses the activation of the phagolysosome in macrophages. In EAU, the IL-6 produced by the RPE promotes the activation of phagolysosomes in macrophages. These results demonstrate that under healthy conditions, RPE promotes an altered pathway of phagocytized material in macrophages with implications on antigen processing and clearance. PMID:28241314

  1. Stimulation of peritoneal cell arginase by bacterial lipopolysaccharides.

    PubMed

    Ryan, J L; Yohe, W B; Morrison, D C

    1980-05-01

    The conditions under which bacterial endotoxins stimulate arginase production in mouse peritoneal macrophages have been defined. Both lipid-A and lipid-A-associated protein are potent activators. Fetal calf serum and normal mouse serum enhance macrophage arginase levels in the presence and absence of lipopolysaccharide (LPS). LPS in the amount of 10(-1) microgram/ml represents a maximal stimulus for macrophage arginase production and release. Thioglycollate-elicited peritoneal cells have increased arginase activity, compared with resident cells. This activity can be stimulated further by the addition of LPS. Arginase levels may alter the outcome of in vitro immunologic processes by depleting arginine and may also serve as a useful indicator of the state of activation of macrophages.

  2. A critical role for suppressor of cytokine signalling 3 in promoting M1 macrophage activation and function in vitro and in vivo.

    PubMed

    Arnold, Christina E; Whyte, Claire S; Gordon, Peter; Barker, Robert N; Rees, Andrew J; Wilson, Heather M

    2014-01-01

    Macrophages respond to their microenvironment and develop polarized functions critical for orchestrating appropriate inflammatory responses. Classical (M1) activation eliminates pathogens while alternative (M2) activation promotes regulation and repair. M1 macrophage activation is strongly associated with suppressor of cytokine signalling 3 (SOCS3) expression in vitro, but the functional consequences of this are unclear and the role of SOCS3 in M1-macrophage polarization in vivo remains controversial. To address these questions, we defined the characteristics and function of SOCS3-expressing macrophages in vivo and identified potential mechanisms of SOCS3 action. Macrophages infiltrating inflamed glomeruli in a model of acute nephritis show significant up-regulation of SOCS3 that co-localizes with the M1-activation marker, inducible nitric oxide synthase. Numbers of SOCS3(hi) -expressing, but not SOCS1(hi) -expressing, macrophages correlate strongly with the severity of renal injury, supporting their inflammatory role in vivo. Adoptive transfer of SOCS3-short interfering RNA-silenced macrophages into a peritonitis model demonstrated the importance of SOCS3 in driving production of pro-inflammatory IL-6 and nitric oxide, while curtailing expression of anti-inflammatory IL-10 and SOCS1. SOCS3-induced pro-inflammatory effects were due, at least in part, to its role in controlling activation and nuclear accumulation of nuclear factor-κB and activity of phosphatidylinositol 3-kinase. We show for the first time that SOCS3 also directs the functions of human monocyte-derived macrophages, including efficient M1-induced cytokine production (IL-1β, IL-6, IL-23, IL-12), attenuated signal transducer and activator of transcription 3 activity and ability of antigen-loaded macrophages to drive T-cell responses. Hence, M1-associated SOCS3 was a positive regulator of pro-inflammatory responses in our rodent models and up-regulated SOCS3 is essential for effective M1-macrophage

  3. Alternatively Activated (M2) Macrophage Phenotype Is Inducible by Endothelin-1 in Cultured Human Macrophages

    PubMed Central

    Soldano, Stefano; Pizzorni, Carmen; Paolino, Sabrina; Trombetta, Amelia Chiara; Montagna, Paola; Brizzolara, Renata; Ruaro, Barbara; Sulli, Alberto; Cutolo, Maurizio

    2016-01-01

    Background Alternatively activated (M2) macrophages are phenotypically characterized by the expression of specific markers, mainly macrophage scavenger receptors (CD204 and CD163) and mannose receptor-1 (CD206), and participate in the fibrotic process by over-producing pro-fibrotic molecules, such as transforming growth factor-beta1 (TGFbeta1) and metalloproteinase (MMP)-9. Endothelin-1 (ET-1) is implicated in the fibrotic process, exerting its pro-fibrotic effects through the interaction with its receptors (ETA and ETB). The study investigated the possible role of ET-1 in inducing the transition from cultured human macrophages into M2 cells. Methods Cultured human monocytes (THP-1 cell line) were activated into macrophages (M0 macrophages) with phorbol myristate acetate and subsequently maintained in growth medium (M0-controls) or treated with either ET-1 (100nM) or interleukin-4 (IL-4, 10ng/mL, M2 inducer) for 72 hours. Similarly, primary cultures of human peripheral blood monocyte (PBM)-derived macrophages obtained from healthy subjects, were maintained in growth medium (untreated cells) or treated with ET-1 or IL-4 for 6 days. Both M0 and PBM-derived macrophages were pre-treated with ET receptor antagonist (ETA/BRA, bosentan 10-5M) for 1 hour before ET-1 stimulation. Protein and gene expression of CD204, CD206, CD163, TGFbeta1 were analysed by immunocytochemistry, Western blotting and quantitative real time polymerase chain reaction (qRT-PCR). Gene expression of interleukin(IL)-10 and macrophage derived chemokine (CCL-22) was evaluated by qRT-PCR. MMP-9 production was investigated by gel zymography. Results ET-1 significantly increased the expression of M2 phenotype markers CD204, CD206, CD163, IL-10 and CCL-22, and the production of MMP-9 in both cultures of M0 and PBM-derived macrophages compared to M0-controls and untreated cells. In cultured PBM-derived macrophages, ET-1 increased TGFbeta1 protein and gene expression compared to untreated cells. The ET-1

  4. Molecular and epigenetic basis of macrophage polarized activation.

    PubMed

    Porta, Chiara; Riboldi, Elena; Ippolito, Alessandro; Sica, Antonio

    2015-08-01

    Macrophages are unique cells for origin, heterogeneity and plasticity. At steady state most of macrophages are derived from fetal sources and maintained in adulthood through self-renewing. Despite sharing common progenitors, a remarkable heterogeneity characterized tissue-resident macrophages indicating that local signals educate them to express organ-specific functions. Macrophages are extremely plastic: chromatin landscape and transcriptional programs can be dynamically re-shaped in response to microenvironmental changes. Owing to their ductility, macrophages are crucial orchestrators of both initiation and resolution of immune responses and key supporters of tissue development and functions in homeostatic and pathological conditions. Herein, we describe current understanding of heterogeneity and plasticity of macrophages using the M1-M2 dichotomy as operationally useful simplification of polarized activation. We focused on the complex network of signaling cascades, metabolic pathways, transcription factors, and epigenetic changes that control macrophage activation. In particular, this network was addressed in sepsis, as a paradigm of a pathological condition determining dynamic macrophage reprogramming.

  5. Antiorthostatic suspension stimulates profiles of macrophage activation in mice

    NASA Technical Reports Server (NTRS)

    Miller, E. S.; Bates, R. A.; Koebel, D. A.; Sonnenfeld, G.

    1999-01-01

    The antiorthostatic suspension model simulates certain physiological effects of spaceflight. We have previously reported BDF1 mice suspended by the tail in the antiorthostatic orientation for 4 days express high levels of resistance to virulent Listeria monocytogenesinfection. In the present study, we examined whether the increased resistance to this organism correlates with profiles of macrophage activation, given the role of the macrophage in killing this pathogen in vivo. We infected BDF1 mice with a lethal dose of virulent L. monocytogenes on day 4 of antiorthostatic suspension and 24 h later constructed profiles of macrophage activation. Viable listeria could not be detected in mice suspended in the antiorthostatic orientation 24 h after infection. Flow cytometric analysis revealed the numbers of granulocytes and mononuclear phagocytes in the spleen of infected mice were not significantly altered as a result of antiorthostatic suspension. Splenocytes from antiorthostatically suspended infected mice produced increased titers of IL-1. Serum levels of neopterin, a nucleotide metabolite secreted by activated macrophages, were enhanced in mice infected during antiorthostatic suspension, but not in antiorthostatically suspended naive mice. Splenic macrophages from mice infected on day 4 of suspension produced enhanced levels of lysozyme. In contrast to the results from antiorthostatically suspended infected mice, macrophages from antiorthostatically suspended uninfected mice did not express enhanced bactericidal activities. The collective results indicate that antiorthostatic suspension can stimulate profiles of macrophage activation which correlate with increased resistance to infection by certain classes of pathogenic bacteria.

  6. Toxoplasma gondii Chitinase Induces Macrophage Activation

    PubMed Central

    Almeida, Fausto; Sardinha-Silva, Aline; da Silva, Thiago Aparecido; Pessoni, André Moreira; Pinzan, Camila Figueiredo; Alegre-Maller, Ana Claudia Paiva; Cecílio, Nerry Tatiana; Moretti, Nilmar Silvio; Damásio, André Ricardo Lima; Pedersoli, Wellington Ramos; Mineo, José Roberto; Silva, Roberto Nascimento; Roque-Barreira, Maria Cristina

    2015-01-01

    Toxoplasma gondii is an obligate intracellular protozoan parasite found worldwide that is able to chronically infect almost all vertebrate species, especially birds and mammalians. Chitinases are essential to various biological processes, and some pathogens rely on chitinases for successful parasitization. Here, we purified and characterized a chitinase from T. gondii. The enzyme, provisionally named Tg_chitinase, has a molecular mass of 13.7 kDa and exhibits a Km of 0.34 mM and a Vmax of 2.64. The optimal environmental conditions for enzymatic function were at pH 4.0 and 50°C. Tg_chitinase was immunolocalized in the cytoplasm of highly virulent T. gondii RH strain tachyzoites, mainly at the apical extremity. Tg_chitinase induced macrophage activation as manifested by the production of high levels of pro-inflammatory cytokines, a pathogenic hallmark of T. gondii infection. In conclusion, to our knowledge, we describe for the first time a chitinase of T. gondii tachyzoites and provide evidence that this enzyme might influence the pathogenesis of T. gondii infection. PMID:26659253

  7. Enterococcus faecalis infection activates phosphatidylinositol 3-kinase signaling to block apoptotic cell death in macrophages.

    PubMed

    Zou, Jun; Shankar, Nathan

    2014-12-01

    Apoptosis is an intrinsic immune defense mechanism in the host response to microbial infection. Not surprisingly, many pathogens have evolved various strategies to manipulate this important pathway to benefit their own survival and dissemination in the host during infection. To our knowledge, no attempts have been made to explore the host cell survival signals modulated by the bacterium Enterococcus faecalis. Here, we show for the first time that during early stages of infection, internalized enterococci can prevent host cell (RAW264.7 cells, primary macrophages, and mouse embryonic fibroblasts [MEFs]) apoptosis induced by a wide spectrum of proapoptotic stimuli. Activation of caspase 3 and cleavage of the caspase 3 substrate poly(ADP-ribose) polymerase were inhibited in E. faecalis-infected cells, indicating that E. faecalis protects macrophages from apoptosis by inhibiting caspase 3 activation. This antiapoptotic activity in E. faecalis-infected cells was dependent on the activation of the phosphatidylinositol 3-kinase (PI3K)/Akt signaling pathway, which resulted in the increased expression of the antiapoptotic factor Bcl-2 and decreased expression of the proapoptotic factor Bax. Further analysis revealed that active E. faecalis physiology was important for inhibition of host cell apoptosis, and this feature seemed to be a strain-independent trait among E. faecalis isolates. Employing a mouse peritonitis model, we also determined that cells collected from the peritoneal lavage fluid of E. faecalis-infected mice showed reduced levels of apoptosis compared to cells from uninfected mice. These results show early modulation of apoptosis during infection and have important implications for enterococcal pathogenesis.

  8. Inhibitory effect of deferoxamine or macrophage activation on transformation of Paracoccidioides brasiliensis conidia ingested by macrophages: reversal by holotransferrin.

    PubMed

    Cano, L E; Gomez, B; Brummer, E; Restrepo, A; Stevens, D A

    1994-04-01

    Conidia of P. brasiliensis ingested by murine macrophages at 37 degrees C showed enhanced transformation to yeast cells and further intracellular growth compared with conidia in culture medium alone. Treatment of macrophages with the iron chelator deferoxamine inhibited the intracellular conidium-to-yeast transformation. Cytokine-activated macrophages could also exert this inhibitory effect. Holotransferrin reversed the inhibitory effect of either deferoxamine or activated macrophages on intracellular conidium-to-yeast transformation. These results indicate that iron restriction is one of the mechanisms by which activated macrophages control the intracellular transformation of ingested conidia and growth of yeast cells.

  9. Inhibitory effect of deferoxamine or macrophage activation on transformation of Paracoccidioides brasiliensis conidia ingested by macrophages: reversal by holotransferrin.

    PubMed Central

    Cano, L E; Gomez, B; Brummer, E; Restrepo, A; Stevens, D A

    1994-01-01

    Conidia of P. brasiliensis ingested by murine macrophages at 37 degrees C showed enhanced transformation to yeast cells and further intracellular growth compared with conidia in culture medium alone. Treatment of macrophages with the iron chelator deferoxamine inhibited the intracellular conidium-to-yeast transformation. Cytokine-activated macrophages could also exert this inhibitory effect. Holotransferrin reversed the inhibitory effect of either deferoxamine or activated macrophages on intracellular conidium-to-yeast transformation. These results indicate that iron restriction is one of the mechanisms by which activated macrophages control the intracellular transformation of ingested conidia and growth of yeast cells. PMID:8132359

  10. Paeonia japonica, Houttuynia cordata, and Aster scaber water extracts induce nitric oxide and cytokine production by lipopolysaccharide-activated macrophages.

    PubMed

    Kim, Jin; Park, Chang-Shin; Lim, Yunsook; Kim, Hyun-Sook

    2009-04-01

    Natural products are increasingly recognized as potential targets for drug discovery and development. We previously reported that Paeonia japonica, Houttuynia cordata, and Aster scaber enhanced macrophage activation both in vitro and in vivo. In the present study we investigated the immunomodulating effects of these plants on lipopolysacharide (LPS)-stimulated macrophages. An aqueous extract of each plant was administered to female BALB/c mice every other day for 4 weeks. Peritoneal macrophages were then collected and incubated to examine the immunoreactivity of macrophages against LPS at different time points. The expression levels of inducible nitric oxide (NO) synthetase (iNOS), cyclooxygenase (COX)-2, and inhibitory factor kappaB alpha (IkappaBalpha) proteins and the production of NO metabolite (nitrite), prostaglandin (PG) E(2), and the pro-inflammatory cytokines interleukin-1beta, interleukin-6, and tumor necrosis factor-alpha were determined in the activated macrophages treated with extracts from each plant individually or combined. High levels of pro-inflammatory cytokines were produced by A. scaber-, P. japonica-, and H. cordata-treated macrophages following 24 hours of LPS stimulation. P. japonica, H. cordata, and A. scaber treatment also induced the production of nitrate by LPS-treated macrophages. Induction of iNOS mRNA and protein was also different in each group. PGE(2) secretion was up-regulated by all extract-treated macrophages at early time points; however, no significant differences were observed between the groups by 8 hours post-LPS stimulation. Treatment with A. scaber extract resulted in the highest levels of IkappaBalpha degradation. Our findings illustrate that the natural plant products P. japonica, H. cordata, and A. scaber may enhance immune function by modulating ex vivo pro-inflammatory cytokine and NO production as well as the expression of iNOS and COX-2.

  11. Activating transcription factor 4 underlies the pathogenesis of arsenic trioxide-mediated impairment of macrophage innate immune functions.

    PubMed

    Srivastava, Ritesh K; Li, Changzhao; Wang, Yong; Weng, Zhiping; Elmets, Craig A; Harrod, Kevin S; Deshane, Jessy S; Athar, Mohammad

    2016-10-01

    Chronic arsenic exposure to humans is considered immunosuppressive with augmented susceptibility to several infectious diseases. The exact molecular mechanisms, however, remain unknown. Earlier, we showed the involvement of unfolded protein response (UPR) signaling in arsenic-mediated impairment of macrophage functions. Here, we show that activating transcription factor 4 (ATF4), a UPR transcription factor, regulates arsenic trioxide (ATO)-mediated dysregulation of macrophage functions. In ATO-treated ATF4(+/+) wild-type mice, a significant down-regulation of CD11b expression was associated with the reduced phagocytic functions of peritoneal and lung macrophages. This severe immuno-toxicity phenotype was not observed in ATO-treated ATF4(+/-) heterozygous mice. To confirm these observations, we demonstrated in Raw 264.7 cells that ATF4 knock-down rescues ATO-mediated impairment of macrophage functions including cytokine production, bacterial engulfment and clearance of engulfed bacteria. Sustained activation of ATF4 by ATO in macrophages induces apoptosis, while diminution of ATF4 expression protects against ATO-induced apoptotic cell death. Raw 264.7 cells treated with ATO also manifest dysregulated Ca(++) homeostasis. ATO induces Ca(++)-dependent calpain-1 and caspase-12 expression which together regulated macrophage apoptosis. Additionally, apoptosis was also induced by mitochondria-regulated pathway. Restoring ATO-impaired Ca(++) homeostasis in ER/mitochondria by treatments with the inhibitors of inositol 1,4,5-trisphosphate receptor (IP3R) and voltage-dependent anion channel (VDAC) attenuate innate immune functions of macrophages. These studies identify a novel role for ATF4 in underlying pathogenesis of macrophage dysregulation and immuno-toxicity of arsenic.

  12. Jacalin-Activated Macrophages Exhibit an Antitumor Phenotype

    PubMed Central

    Danella Polli, Cláudia; Pereira Ruas, Luciana; Chain Veronez, Luciana; Herrero Geraldino, Thais; Rossetto de Morais, Fabiana; Roque-Barreira, Maria Cristina; Pereira-da-Silva, Gabriela

    2016-01-01

    Tumor-associated macrophages (TAMs) have an ambiguous and complex role in the carcinogenic process, since these cells can be polarized into different phenotypes (proinflammatory, antitumor cells or anti-inflammatory, protumor cells) by the tumor microenvironment. Given that the interactions between tumor cells and TAMs involve several players, a better understanding of the function and regulation of TAMs is crucial to interfere with their differentiation in attempts to skew TAM polarization into cells with a proinflammatory antitumor phenotype. In this study, we investigated the modulation of macrophage tumoricidal activities by the lectin jacalin. Jacalin bound to macrophage surface and induced the expression and/or release of mainly proinflammatory cytokines via NF-κB signaling, as well as increased iNOS mRNA expression, suggesting that the lectin polarizes macrophages toward the antitumor phenotype. Therefore, tumoricidal activities of jacalin-stimulated macrophages were evaluated. High rates of tumor cell (human colon, HT-29, and breast, MCF-7, cells) apoptosis were observed upon incubation with supernatants from jacalin-stimulated macrophages. Taken together, these results indicate that jacalin, by exerting a proinflammatory activity, can direct macrophages to an antitumor phenotype. Deep knowledge of the regulation of TAM functions is essential for the development of innovative anticancer strategies. PMID:27119077

  13. MIF-driven activation of macrophages induces killing of intracellular Trypanosoma cruzi dependent on endogenous production of tumor necrosis factor, nitric oxide and reactive oxygen species.

    PubMed

    Cutrullis, Romina A; Petray, Patricia B; Corral, Ricardo S

    2017-02-01

    The proinflammatory cytokine macrophage migration inhibitory factor (MIF) is a key player in innate immunity. MIF has been considered critical for controlling acute infection by the protozoan Trypanosoma cruzi, but the underlying mechanisms are poorly understood. Our study aimed to analyze whether MIF could favor microbicidal activity of the macrophage, a site where T. cruzi grows and the initial effector cell against this parasite. Using murine macrophages infected in vitro, we examined the effect of MIF on their parasiticidal ability and attempted to identify inflammatory agents involved in MIF-induced protection. Our findings show that MIF is readily secreted from peritoneal macrophages upon T. cruzi infection. MIF activates both primary and J774 phagocytes boosting the endogenous production of tumor necrosis factor-alpha via mitogen-activated protein kinase p38 signaling, as well as the release of nitric oxide and reactive oxygen species, leading to enhanced pathogen elimination. MIF can also potentiate the effect of interferon-gamma on T. cruzi killing by J774 and mouse peritoneal macrophages, rendering these cells more competent in reducing intracellular parasite burden. The present results unveil a novel innate immune pathway that contributes to host defense and broaden our understanding of the regulation of inflammatory mediators implicated in early parasite containment that is decisive for resistance to T. cruzi infection.

  14. Glutamine Modulates Macrophage Lipotoxicity

    PubMed Central

    He, Li; Weber, Kassandra J.; Schilling, Joel D.

    2016-01-01

    Obesity and diabetes are associated with excessive inflammation and impaired wound healing. Increasing evidence suggests that macrophage dysfunction is responsible for these inflammatory defects. In the setting of excess nutrients, particularly dietary saturated fatty acids (SFAs), activated macrophages develop lysosome dysfunction, which triggers activation of the NLRP3 inflammasome and cell death. The molecular pathways that connect lipid stress to lysosome pathology are not well understood, but may represent a viable target for therapy. Glutamine uptake is increased in activated macrophages leading us to hypothesize that in the context of excess lipids glutamine metabolism could overwhelm the mitochondria and promote the accumulation of toxic metabolites. To investigate this question we assessed macrophage lipotoxicity in the absence of glutamine using LPS-activated peritoneal macrophages exposed to the SFA palmitate. We found that glutamine deficiency reduced lipid induced lysosome dysfunction, inflammasome activation, and cell death. Under glutamine deficient conditions mTOR activation was decreased and autophagy was enhanced; however, autophagy was dispensable for the rescue phenotype. Rather, glutamine deficiency prevented the suppressive effect of the SFA palmitate on mitochondrial respiration and this phenotype was associated with protection from macrophage cell death. Together, these findings reveal that crosstalk between activation-induced metabolic reprogramming and the nutrient microenvironment can dramatically alter macrophage responses to inflammatory stimuli. PMID:27077881

  15. Effects of Opsonization and Gamma Interferon on Growth of Brucella Melitensis 16M in Mouse Peritoneal Macrophages In Vitro

    DTIC Science & Technology

    2000-01-01

    SUBTITLE Effects of Opsonization and Gamma Interferon on Growth of Brucella , melitensis 16M in Mouse Peritoneal Microphages rom In Vitro 3. REPORT...with Brucella melitensis 16M treated with complement- and/or antibody-rich serum. Mouse serum rich in antibody against Brucella lipopolysaccnaride...pathogens of humans and livestock. Brucella meli- tensis usually infects sheep, goats , and camels and is the most pathogenic species for humans (1). Like

  16. Structural definition of a potent macrophage activating factor derived from vitamin D3-binding protein with adjuvant activity for antibody production.

    PubMed

    Yamamoto, N

    1996-10-01

    Incubation of human vitamin D3-binding protein (Gc protein), with a mixture of immobilized beta-galactosidase and sialidase, efficiently generated a potent macrophage activating factor, a protein with N-acetylgalactosamine as the remaining sugar. Stepwise incubation of Gc protein with immobilized beta-galactosidase and sialidase, and isolation of the intermediates with immobilized lectins, revealed that either sequence of hydrolysis of Gc glycoprotein by these glycosidases yields the macrophage-activating factor, implying that Gc protein carries a trisaccharide composed of N-acetylgalactosamine and dibranched galactose and sialic acid termini. A 3 hr incubation of mouse peritoneal macrophages with picomolar amounts of the enzymatically generated macrophage-activating factor (GcMAF) resulted in a greatly enhanced phagocytic activity. Administration of a minute amount (10-50 pg/mouse) of GcMAF resulted in a seven- to nine-fold enhanced phagocytic activity of macrophages. Injection of sheep red blood cells (SRBC) along with GcMAF into mice produced a large number of anti-SRBC antibody secreting splenic cells in 2-4 days.

  17. Early activation of splenic macrophages by tumor necrosis factor alpha is important in determining the outcome of experimental histoplasmosis in mice.

    PubMed Central

    Wu-Hsieh, B A; Lee, G S; Franco, M; Hofman, F M

    1992-01-01

    Experimental infection of animals with Histoplasma capsulatum caused a massive macrophage infiltration into the spleen and induced the production of tumor necrosis factor alpha (TNF-alpha) locally. The cytokine was also produced in vitro by peritoneal exudate macrophages exposed to a large inoculum of yeast cells. Depletion of the cytokine by injection of polyclonal sheep anti-TNF-alpha antibody was detrimental to sublethally infected mice. Fungous burdens in the spleens of TNF-alpha-depleted mice were higher than they were in the infected control mice at days 2, 7, and 9 after infection, and the antibody-treated animals succumbed to the infection. Histopathological study of spleen sections revealed that splenic macrophages were not able to control proliferation of intracellular yeasts as a result of TNF-alpha depletion. It seems that TNF-alpha plays a role in early activation of splenic macrophages which is important in controlling the outcome of an infection. Images PMID:1398934

  18. Alternatively activated macrophages promote pancreatic fibrosis in chronic pancreatitis

    PubMed Central

    Xue, Jing; Sharma, Vishal; Hsieh, Michael H.; Chawla, Ajay; Murali, Ramachandran; Pandol, Stephen J.; Habtezion, Aida

    2015-01-01

    Chronic pancreatitis (CP) is a progressive and irreversible inflammatory and fibrotic disease with no cure. Unlike acute pancreatitis, we find that alternatively activated macrophages (AAMs) are dominant in mouse and human CP. AAMs are dependent on IL-4 and IL-13 signaling and we show that mice lacking IL-4Rα, myeloid specific IL-4Rα, and IL-4/IL-13 were less susceptible to pancreatic fibrosis. Furthermore, we demonstrate that mouse and human pancreatic stellate cells (PSCs) are a source of IL-4/IL-13. Notably, we show that pharmacologic inhibition of IL-4/IL-13 in human ex-vivo studies as well as in established mouse CP decreases pancreatic AAMs and fibrosis. We identify a critical role for macrophages in pancreatic fibrosis and in turn PSCs as important inducers of macrophage alternative activation. Our study challenges and identifies pathways involved in cross talk between macrophages and PSCs that can be targeted to reverse or halt pancreatic fibrosis progression. PMID:25981357

  19. Phagocytic and chemiluminescent responses of mouse peritoneal macrophages to living and killed Salmonella typhimurium and other bacteria

    SciTech Connect

    Tomita, T.; Blumenstock, E.; Kanegasaki, S.

    1981-06-01

    In the presence of luminol, resident as well as thioglycolate-induced and immunized macrophages emitted chemiluminescence more efficiently when the cells were exposed to living Salmonella typhimurium than when they were exposed to the same bacterium killed by ultraviolet light or heat. This phenomenon was observed whether or not the bacterium was opsonized. The different response to living and killed bacteria was also found with Escherichia coli, Pseudomonas aeruginosa, Proteus morganii, and Enterobacter aerogenes, but not with Shigella sonnei, Klebsiella pneumoniae, and Propionibacterium acnes. The results suggest that macrophages respond better to living, motile bacteria than to nonmotile or killed bacteria. The experimental results obtained with motility mutants of S. typhimurium, E. coli, and P. aeruginosa confirm that macrophages exposed to the motile bacteria emit chemiluminescence more efficiently and ingest the motile bacteria at a much faster rate than the nonmotile bacteria.

  20. Identification of S-(2,3-dihydroxypropyl)cystein in a macrophage-activating lipopeptide from Mycoplasma fermentans.

    PubMed

    Mühlradt, P F; Meyer, H; Jansen, R

    1996-06-18

    Mycoplasmas are capable of stimulating monocytes and macrophages to release cytokines, prostaglandins, and nitric oxide. The aim of this study was to characterize the chemical nature of the previously isolated [Mühlradt, P. F., & Frisch, M. (1994) Infect. Immun. 62, 3801-3807] macrophage-stimulating material "MDHM" from Mycoplasma fermentans. Mycoplasmas were delipidated, and MDHM activity was extracted with octyl glucoside and further purified by reversed-phase HPLC. Macrophage-stimulating activity was monitored by nitric oxide release from peritoneal macrophages from C3H/HeJ endotoxin low responder mice. HPLC-purified MDHM was rechromatographed on an analytic scale RP 18 column before and after proteinase K treatment. Proteinase treatment did not diminish biological activity but shifted MDHM elution toward higher lipophilicity, suggesting that the macrophage-stimulating activity might reside in the lipopeptide moiety of a lipoprotein. Proteinase K-treated MDHM was hydrolyzed, amino groups were dansylated, and the dansylated material was isolated by HPLC. Dansylated S-(2,3-dihydroxypropyl)cystein (glycerylcystein thioether), typical for Braun's murein lipoprotein, and Dns-Gly and Dns-Thr were identified by tandem mass spectrometry. These amino acids were isolated from biologically active but not from the neighboring inactive HPLC fractions. IR spectra from proteinase K-treated, HPLC-purified MDHM and those from the synthetic lipopeptide [2,3-bis(palmitoyloxy)-(2-RS)-propyl]-N-palmitoyl-(R)-CysSerSer AsnAla were very similar. The data, taken together, indicate that lipoproteins of a nature previously detected in eubacteria are expressed in M. fermentans and that at least one of these lipoproteins and a lipopeptide derived from it constitute the macrophage-activating principle MDHM from these mycoplasmas.

  1. The effects of vitamin D binding protein-macrophage activating factor and colony-stimulating factor-1 on hematopoietic cells in normal and osteopetrotic rats.

    PubMed

    Benis, K A; Schneider, G B

    1996-10-15

    Osteopetrosis is a heterogeneous group of bone disorders characterized by the failure of osteoclasts to resorb bone and by several immunological defects including macrophage dysfunction. Two compounds, colony-stimulating factor-1 (CSF-1) and vitamin D-binding protein-macrophage activating factor (DBP-MAF) were used in the present study to evaluate their effects on the peritoneal population of cells and on cells within the bone marrow microenvironment in normal and incisors absent (ia) osteopetrotic rats. Previous studies in this laboratory have demonstrated that administration of DBP-MAF to newborn ia animals results in a substantial increase in bone marrow cavity size due to upregulated osteoclast function. To study the effects of these compounds on the macrophage/osteoclast precursors, DBP-MAF, CSF-1, and the combination of these compounds were given to newborn ia and normal littermate animals. Both the normal and mutant phenotypes responded similarly when treated with these compounds. Rats exhibited a profound shift toward the macrophage lineage from the neutrophil lineage when compared with vehicle-treated control animals after treatment with these compounds. In the in vivo peritoneal lavage study, animals received injections of CSF-1, DBP-MAF or DBP-MAF/CSF-1 over a 4-week period. The various types of cells in the peritoneal cavity were then enumerated. The in vitro study consisted of cells isolated from the bone marrow microenvironment and cultured on feeder layers of CSF-1, DBP-MAF, or DBP-MAF/CSF-1 for colony enumeration. The increase in macrophage numbers at the expense of neutrophil numbers could be seen in both the in vivo and in vitro experiments. The macrophage/osteoclast and neutrophil lineages have a common precursor, the granulocyte/macrophage colony-forming cell (GM-CFC). With the addition of CSF-1, the GM-CFC precursor may be induced into the macrophage/osteoclast lineage rather than the granulocyte lineage. This increased pool of cells in the

  2. CDDO-Me Redirects Activation of Breast Tumor Associated Macrophages

    PubMed Central

    Ball, Michael S.; Shipman, Emilie P.; Kim, Hyunjung; Liby, Karen T.; Pioli, Patricia A.

    2016-01-01

    Tumor-associated macrophages can account for up to 50% of the tumor mass in breast cancer patients and high TAM density is associated with poor clinical prognosis. Because TAMs enhance tumor growth, development, and metastatic potential, redirection of TAM activation may have significant therapeutic benefit. Our studies in primary human macrophages and murine breast TAMs suggest that the synthetic oleanane triterpenoid CDDO-methyl ester (CDDO-Me) reprograms the activation profile of TAMs from tumor-promoting to tumor-inhibiting. We show that CDDO-Me treatment inhibits expression of IL-10 and VEGF in stimulated human M2 macrophages and TAMs but increases expression of TNF-α and IL-6. Surface expression of CD206 and CD163, which are characteristic of M2 activation, is significantly attenuated by CDDO-Me. In contrast, CDDO-Me up-regulates surface expression of HLA-DR and CD80, which are markers of M1 activation, and importantly potentiates macrophage activation of autologous T cells but inhibits endothelial cell vascularization. These results show for the first time that CDDO-Me redirects activation of M2 macrophages and TAMs from immune-suppressive to immune-stimulatory, and implicate a role for CDDO-Me as an immunotherapeutic in the treatment of breast and potentially other types of cancer. PMID:26918785

  3. Update on the role of alternatively activated macrophages in asthma.

    PubMed

    Jiang, Zhilong; Zhu, Lei

    2016-01-01

    Lung macrophages link innate and adaptive immune responses during allergic airway inflammatory responses. Alveolar macrophages (AMs) and interstitial macrophages are two different phenotypes that differentially exert immunological function under physiological and pathological conditions. Exposure to pathogen induces polarization of AM cells into classically activated macrophages (M1 cells) and alternatively activated macrophages (M2 cells). M1 cells dominantly express proinflammatory cytokines such as TNF-α and IL-1 β and induce lung inflammation and tissue damage. M2 cells are further divided into M2a and M2c subsets. M2a cells dominantly produce allergic cytokines IL-4 and IL-13, but M2c cells dominantly produce anti-inflammatory cytokine IL-10. M2a and M2c cells are differently involved in initiation, inflammation resolution, and tissue remodeling in the different stages of asthma. Microenvironment dynamically influences polarization of AM cells. Cytokines, chemokines, and immune-regulatory cells interplay and affect the balance between the polarization of M1 and M2 cells, subsequently influencing disease progression. Thus, modulation of AM phenotypes through molecular intervention has therapeutic potential in the treatment of asthma and other allergic inflammatory diseases. This review updated recent advances in polarization and functional specialization of these macrophage subtypes with emphasis on modulation of polarization of M2 cells in asthma of human subjects and animal models.

  4. Update on the role of alternatively activated macrophages in asthma

    PubMed Central

    Jiang, Zhilong; Zhu, Lei

    2016-01-01

    Lung macrophages link innate and adaptive immune responses during allergic airway inflammatory responses. Alveolar macrophages (AMs) and interstitial macrophages are two different phenotypes that differentially exert immunological function under physiological and pathological conditions. Exposure to pathogen induces polarization of AM cells into classically activated macrophages (M1 cells) and alternatively activated macrophages (M2 cells). M1 cells dominantly express proinflammatory cytokines such as TNF-α and IL-1 β and induce lung inflammation and tissue damage. M2 cells are further divided into M2a and M2c subsets. M2a cells dominantly produce allergic cytokines IL-4 and IL-13, but M2c cells dominantly produce anti-inflammatory cytokine IL-10. M2a and M2c cells are differently involved in initiation, inflammation resolution, and tissue remodeling in the different stages of asthma. Microenvironment dynamically influences polarization of AM cells. Cytokines, chemokines, and immune-regulatory cells interplay and affect the balance between the polarization of M1 and M2 cells, subsequently influencing disease progression. Thus, modulation of AM phenotypes through molecular intervention has therapeutic potential in the treatment of asthma and other allergic inflammatory diseases. This review updated recent advances in polarization and functional specialization of these macrophage subtypes with emphasis on modulation of polarization of M2 cells in asthma of human subjects and animal models. PMID:27350756

  5. Macrophages generate reactive oxygen species in response to minimally oxidized LDL: TLR4- and Syk-dependent activation of Nox2

    PubMed Central

    Bae, Yun Soo; Lee, Jee Hyun; Choi, Soo Ho; Kim, Sunah; Almazan, Felicidad; Witztum, Joseph L.; Miller, Yury I.

    2009-01-01

    Oxidative modification of low-density lipoprotein (LDL) plays a causative role in the development of atherosclerosis. In this study, we demonstrate that minimally oxidized LDL (mmLDL) stimulates intracellular reactive oxygen species (ROS) generation in macrophages through NADPH oxidase 2 (gp91phox/Nox2), which in turn induces production of RANTES and migration of smooth muscle cells. Peritoneal macrophages from gp91phox/Nox2−/− mice or J774 macrophages in which Nox2 was knocked down by siRNA failed to generate ROS in response to mmLDL. Because mmLDL-induced cytoskeletal changes were dependent on TLR4, we analyzed ROS generation in peritoneal macrophages from wild type, TLR4−/−, or MyD88−/− mice and found that mmLDL-mediated ROS was generated in a TLR4-dependent, but MyD88-independent manner. Furthermore, we found that ROS generation required the recruitment and activation of spleen tyrosine kinase (Syk) and that mmLDL also induced PLCγ1 phosphorylation and PKC membrane translocation. Importantly, the PLCγ1 phosphorylation was reduced in J774 cells expressing Syk-specific shRNA. Nox2 modulated mmLDL activation of macrophages by regulating the expression of proinflammatory cytokines IL-1β, IL-6 and RANTES. We showed that purified RANTES was able to stimulate migration of mouse aortic smooth muscle cells (MASMC) and addition of neutralizing antibody against RANTES abolished the migration of MASMC stimulated by mmLDL-stimulated macrophages. These results suggest that mmLDL induces generation of ROS through sequential activation of TLR4, Syk, PLCγ1, PKC, and gp91phox/Nox2 and thereby stimulates expression of proinflammatory cytokines. These data help explain mechanisms by which endogenous ligands, such as mmLDL, can induce TLR4-dependent, proatherogenic activation of macrophages. PMID:19096031

  6. Enzymatically-Processed Wheat Bran Enhances Macrophage Activity and Has in Vivo Anti-Inflammatory Effects in Mice

    PubMed Central

    Kang, Hee; Lee, Mi-Gi; Lee, Jae-Kang; Choi, Yong-Hyun; Choi, Yong-Seok

    2016-01-01

    Wheat bran is a rich source of dietary fiber, of which arabinoxylan is the most abundant non-starch polysaccharide. Arabinoxylan has been known to exert in vivo immunological activities. Based on prior findings, we pretreated wheat bran with enzymatic hydrolysis to increase the release of soluble arabinoxylan and investigated whether oral administration of wheat bran altered macrophage activity in a mouse model. After four weeks of treatment, we isolated peritoneal macrophages for phagocytic receptor analysis and lipopolysaccharide (LPS)-induced inflammatory changes. In the second experiment, mice given wheat bran were intraperitoneally stimulated with LPS and serum levels of pro- and anti-inflammatory cytokines were determined. The expression of SRA and CD36, and phagocytic activity increased (p < 0.05, respectively). Ex vivo stimulation of macrophages by LPS resulted in reduced surface expression of CD40 (p < 0.05) and decreased production of nitric oxide (p < 0.005), tumor necrosis factor (TNF)-α (p < 0.005), interleukin (IL)-6 (p < 0.01), and IL-12 (p < 0.05). Mice treated with wheat bran showed decreased levels of serum TNF-α and IL-6 (p < 0.05, respectively) and an increased level of serum anti-inflammatory IL-10 (p < 0.05) in response to intraperitoneal LPS. Enzymatically-processed wheat bran boosts macrophage phagocytic capacity possibly through up-regulation of scavenger receptors and confers anti-inflammatory effects, indicating its potential as an immuno-enhancing functional food. PMID:27043618

  7. Endogenous Epoxygenases Are Modulators of Monocyte/Macrophage Activity

    PubMed Central

    Sugden, Mary C.; Holness, Mark J.; Swales, Karen E.; Warner, Timothy D.; Edin, Matthew L.; Zeldin, Darryl C.; Gilroy, Derek W.; Bishop-Bailey, David

    2011-01-01

    Background Arachidonic acid is metabolized through three major metabolic pathways, the cyclooxygenase, lipoxygenase and CYP450 enzyme systems. Unlike cyclooxygenase and lipoxygenases, the role of CYP450 epoxygenases in monocyte/macrophage-mediated responses is not known. Methodology/Principal Findings When transfected in vitro, CYP2J2 is an efficient activator of anti-inflammatory pathways through the nuclear receptor peroxisome proliferator-activated receptor (PPAR) α. Human monocytes and macrophages contain PPARα and here we show they express the epoxygenases CYP2J2 and CYP2C8. Inhibition of constitutive monocyte epoxygenases using the epoxygenase inhibitor SKF525A induces cyclooxygenase (COX)-2 expression and activity, and the release of TNFα, and can be reversed by either add back of the endogenous epoxygenase products and PPARα ligand 11,12- epoxyeicosatrienoic acid (EET) or the addition of the selective synthetic PPARα ligand GW7647. In alternatively activated (IL-4-treated) monocytes, in contrast to classically activated cells, epoxygenase inhibition decreased TNFα release. Epoxygenases can be pro-inflammatory via superoxide anion production. The suppression of TNFα by SKF525A in the presence of IL-4 was associated with a reduction in superoxide anion generation and reproduced by the superoxide dismutase MnCl2. Similar to these acute activation studies, in monocyte derived macrophages, epoxygenase inhibition elevates M1 macrophage TNFα mRNA and further decreases M2 macrophage TNFα. Conclusions/Significance In conclusion, epoxygenase activity represents an important endogenous pathway which limits monocyte activation. Moreover endogenous epoxygenases are immuno-modulators regulating monocyte/macrophage activation depending on the underlying activation state. PMID:22028915

  8. Flavocoxid, a dual inhibitor of cyclooxygenase and 5-lipoxygenase, blunts pro-inflammatory phenotype activation in endotoxin-stimulated macrophages

    PubMed Central

    Altavilla, D; Squadrito, F; Bitto, A; Polito, F; Burnett, BP; Di Stefano, V; Minutoli, L

    2009-01-01

    Background and purpose: The flavonoids, baicalin and catechin, from Scutellaria baicalensis and Acacia catechu, respectively, have been used for various clinical applications. Flavocoxid is a mixed extract containing baicalin and catechin, and acts as a dual inhibitor of cyclooxygenase (COX) and 5-lipoxygenase (LOX) enzymes. The anti-inflammatory activity, measured by protein and gene expression of inflammatory markers, of flavocoxid in rat peritoneal macrophages stimulated with Salmonella enteritidis lipopolysaccharide (LPS) was investigated. Experimental approach: LPS-stimulated (1 µg·mL−1) peritoneal rat macrophages were co-incubated with different concentrations of flavocoxid (32–128 µg·mL−1) or RPMI medium for different incubation times. Inducible COX-2, 5-LOX, inducible nitric oxide synthase (iNOS) and inhibitory protein κB-α (IκB-α) levels were evaluated by Western blot analysis. Nuclear factor κB (NF-κB) binding activity was investigated by electrophoretic mobility shift assay. Tumour necrosis factor-α (TNF-α) gene and protein expression were measured by real-time polymerase chain reaction and enzyme-linked immunosorbent assay respectively. Finally, malondialdehyde (MDA) and nitrite levels in macrophage supernatants were evaluated. Key results: LPS stimulation induced a pro-inflammatory phenotype in rat peritoneal macrophages. Flavocoxid (128 µg·mL−1) significantly inhibited COX-2 (LPS = 18 ± 2.1; flavocoxid = 3.8 ± 0.9 integrated intensity), 5-LOX (LPS = 20 ± 3.8; flavocoxid = 3.1 ± 0.8 integrated intensity) and iNOS expression (LPS = 15 ± 1.1; flavocoxid = 4.1 ± 0.4 integrated intensity), but did not modify COX-1 expression. PGE2 and LTB4 levels in culture supernatants were consequently decreased. Flavocoxid also prevented the loss of IκB-α protein (LPS = 1.9 ± 0.2; flavocoxid = 7.2 ± 1.6 integrated intensity), blunted increased NF-κB binding activity (LPS = 9.2 ± 2; flavocoxid = 2.4 ± 0.7 integrated intensity) and the

  9. Killing of Leishmania parasites in activated murine macrophages is based on an L-arginine-dependent process that produces nitrogen derivatives

    SciTech Connect

    Maul, J.R.; Ransijn, A.; Buchmueller-Rouiller, Y. )

    1991-01-01

    The experiments described in this report were aimed at determining whether L-arginine (L-arg)-derived nitrogen oxidation products (nitric oxide, nitrous acid, nitrites) are involved in the intracellular killing of Leishmania parasites by activated murine macrophages in vitro. Peritoneal or bone marrow-derived macrophages were infected with L. enriettii or L. major, then activated by exposure to recombinant murine interferon-gamma or to macrophage activating factor (MAF)-rich media in the presence of lipopolysaccharide. Activation of macrophages in regular (i.e., arginine-containing) culture medium led to complete destruction of the microorganisms within 24 h (L. enriettii) or 48 h (L. major), concomitant with accumulation of nitrites (NO2-) in the culture fluids. When macrophage activation was carried out in L-arg-free medium, however, neither parasite killing nor NO2- production was obtained. A similar inhibition of macrophage leishmanicidal activity and of NO2- release was observed using media treated with arginase (which converts L-arg to urea and ornithine), or supplemented with NG-monomethyl-L-arg or guanidine (which inhibit the conversion of L-arg to nitrogen oxidation products). In all these situations, an excellent correlation between the levels of NO2- production by macrophages and intracellular killing of Leishmania was observed, whereas no strict correlation was detectable between leishmanicidal activity and superoxide production. Intracellular parasite killing by activated macrophages could be prevented by addition of iron salts to the incubation fluids. Incubation of free parasites with NaNO2 at acid pH led to immobilisation, multiplication arrest, and morphological degeneration of the microorganisms. Similarly, exposure of infected cells to NaNO2 led to killing of the intracellular parasite without affecting macrophage viability.

  10. The inhibition of macrophage foam cell formation by 9-cis β-carotene is driven by BCMO1 activity.

    PubMed

    Zolberg Relevy, Noa; Bechor, Sapir; Harari, Ayelet; Ben-Amotz, Ami; Kamari, Yehuda; Harats, Dror; Shaish, Aviv

    2015-01-01

    Atherosclerosis is a major cause of morbidity and mortality in developed societies, and begins when activated endothelial cells recruit monocytes and T-cells from the bloodstream into the arterial wall. Macrophages that accumulate cholesterol and other fatty materials are transformed into foam cells. Several epidemiological studies have demonstrated that a diet rich in carotenoids is associated with a reduced risk of heart disease; while previous work in our laboratory has shown that the 9-cis β-carotene rich alga Dunaliella inhibits atherogenesis in mice. The effect of 9-cis β-carotene on macrophage foam cell formation has not yet been investigated. In the present work, we sought to study whether the 9-cis β-carotene isomer, isolated from the alga Dunaliella, can inhibit macrophage foam cell formation upon its conversion to retinoids. The 9-cis β-carotene and Dunaliella lipid extract inhibited foam cell formation in the RAW264.7 cell line, similar to 9-cis retinoic acid. Furthermore, dietary enrichment with the algal powder in mice resulted in carotenoid accumulation in the peritoneal macrophages and in the inhibition of foam cell formation ex-vivo and in-vivo. We also found that the β-carotene cleavage enzyme β-carotene 15,15'-monooxygenase (BCMO1) is expressed and active in macrophages. Finally, 9-cis β-carotene, as well as the Dunaliella extract, activated the nuclear receptor RXR in hepa1-6 cells. These results indicate that dietary carotenoids, such as 9-cis β-carotene, accumulate in macrophages and can be locally cleaved by endogenous BCMO1 to form 9-cis retinoic acid and other retinoids. Subsequently, these retinoids activate the nuclear receptor RXR that, along with additional nuclear receptors, can affect various metabolic pathways, including those involved in foam cell formation and atherosclerosis.

  11. SKLB023 Blocks Joint Inflammation and Cartilage Destruction in Arthritis Models via Suppression of Nuclear Factor-Kappa B Activation in Macrophage

    PubMed Central

    Liu, Juan; Li, Xiuxia; Pei, Heying; Xiang, Mingli; Chen, Lijuan

    2013-01-01

    Rheumatoid arthritis (RA) is the most common arthritis and is mainly characterized by symmetric polyarticular joint disorders. Our previous study demonstrated a novel small molecule compound (Z)-N-(3-Chlorophenyl)-2-(4-((2,4-dioxothiazolidin-5-ylidene) methyl) phenoxy) acet-amide (SKLB023) showed potently anti-arthritic effects in a rat arthritis model, however, the underlying mechanisms for this are largely unknown. Both NF-κB and macrophages were reported to play important roles in the pathologic processes of RA. The purposes of this study were to indicate whether NF-κB and macrophages contributed to anti-arthritic effects of SKLB023 in two experimental arthritis models. Our results showed that SKLB023 could significantly improve joint inflammation and cartilage destruction both in adjuvant induced arthritis (AIA) and collagen-induced arthritis (CIA) models. We further found that the binding activation of NF-κB to DNA in joint tissues and RAW264.7 macrophages were suppressed by SKLB023. SKLB023 also inhibited the NF-κB activity in peritoneal macrophages by luciferase assay. Furthermore, the number of macrophages in synovial tissues was decreased after the treatment of different doses of SKLB023. The levels of TNF-α, IL-1β, and IL-6 in plasma, and the levels of TNF-α, NO, and IL-1β in peritoneal macrophages were down-regulated by SKLB023. Finally, SKLB023 attenuated the expression of iNOS and COX-2 in vivo and suppressed the phosphorylations of components of the mitogen-activated protein kinases (MAPKs). These observations identify a novel function for SKLB023 as an inhibitor of NF-κB in macrophages of RA, highlighting that SKLB023 was a potential therapeutic strategy for RA. PMID:23431370

  12. ERK5 Activation in Macrophages Promotes Efferocytosis and Inhibits Atherosclerosis

    PubMed Central

    Heo, Kyung-Sun; Cushman, Hannah J.; Akaike, Masashi; Woo, Chang-Hoon; Wang, Xin; Qiu, Xing; Fujiwara, Keigi; Abe, Jun-ichi

    2015-01-01

    Background Efferocytosis is a process by which dead and dying cells are removed by phagocytic cells. Efferocytosis by macrophages is thought to curb the progression of atherosclerosis, but the mechanistic insight of this process is lacking. Methods and Results When macrophages were fed apoptotic cells or treated with pitavastatin in vitro, efferocytosis-related signaling and phagocytic capacity were upregulated in an ERK5 activity–dependent manner. Macrophages isolated from macrophage-specific ERK5-null mice exhibited reduced efferocytosis and levels of gene and protein expression of efferocytosis-related molecules. When these mice were crossed with low-density lipoprotein receptor−/− mice and fed a high-cholesterol diet, atherosclerotic plaque formation was accelerated, and the plaques had more advanced and vulnerable morphology. Conclusions Our results demonstrate that ERK5, which is robustly activated by statins, is a hub molecule that upregulates macrophage efferocytosis, thereby suppressing atherosclerotic plaque formation. Molecules that upregulate ERK5 and its signaling in macrophages may be good drug targets for suppressing cardiovascular diseases. PMID:25001623

  13. Alternatively activated macrophages produce catecholamines to sustain adaptive thermogenesis

    PubMed Central

    Nguyen, Khoa D.; Qiu, Yifu; Cui, Xiaojin; Goh, Y.P. Sharon; Mwangi, Julia; David, Tovo; Mukundan, Lata; Brombacher, Frank; Locksley, Richard M.; Chawla, Ajay

    2011-01-01

    All homeotherms utilize thermogenesis to maintain core body temperature, ensuring that cellular functions and physiologic processes can ensue in cold environments1-3. In the prevailing model, when the hypothalamus senses cold temperatures, it triggers sympathetic discharge, resulting in the release of noradrenaline in brown adipose tissue (BAT) and white adipose tissue (WAT)4,5. Acting via the β3-adrenergic receptors, noradrenaline induces lipolysis in white adipocytes6, whereas it stimulates the expression of thermogenic genes, such as PPARγ coactivator 1a (Ppargc1a), uncoupling protein 1 (Ucp1), and acyl-CoA synthetase long-chain family member 1 (Acsl1), in brown adipocytes7-9. However, the precise nature of all the cell types involved in this efferent loop is not well established. Here we report an unexpected requirement for the interleukin 4 (IL4)-stimulated program of alternative macrophage activation in adaptive thermogenesis. Cold exposure rapidly promoted alternative activation of adipose tissue macrophages, which secrete catecholamines to induce thermogenic gene expression in BAT and lipolysis in WAT. Absence of alternatively activated macrophages impaired metabolic adaptations to cold, whereas administration of IL4 increased thermogenic gene expression, fatty acid mobilization, and energy expenditure, all in a macrophage-dependent manner. We have thus discovered a surprising role for alternatively activated macrophages in the orchestration of an important mammalian stress response, the response to cold. PMID:22101429

  14. An inducible transgene reports activation of macrophages in live zebrafish larvae.

    PubMed

    Sanderson, Leslie E; Chien, An-Tzu; Astin, Jonathan W; Crosier, Kathryn E; Crosier, Philip S; Hall, Christopher J

    2015-11-01

    Macrophages are the most functionally heterogenous cells of the hematopoietic system. Given many diseases are underpinned by inappropriate macrophage activation, macrophages have emerged as a therapeutic target to treat disease. A thorough understanding of what controls macrophage activation will likely reveal new pathways that can be manipulated for therapeutic benefit. Live imaging fluorescent macrophages within transgenic zebrafish larvae has provided a valuable window to investigate macrophage behavior in vivo. Here we describe the first transgenic zebrafish line that reports macrophage activation, as evidenced by induced expression of an immunoresponsive gene 1(irg1):EGFP transgene. When combined with existing reporter lines that constitutively mark macrophages, we reveal this unique transgenic line can be used to live image macrophage activation in response to the bacterial endotoxin lipopolysaccharide and xenografted human cancer cells. We anticipate the Tg(irg1:EGFP) line will provide a valuable tool to explore macrophage activation and plasticity in the context of different disease models.

  15. Periodontitis-activated monocytes/macrophages cause aortic inflammation.

    PubMed

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

    2014-06-04

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

  16. An online coupled peritoneal macrophage/cell membrane chromatography and high-performance liquid chromatography/mass spectrometry method to screen for anti-inflammatory components from the Chinese traditional medicine Chloranthus multistachys Pei.

    PubMed

    Li, Weifeng; Xing, Wei; Wang, Sicen; Fan, Ting; Huang, Huimin; Niu, Xiaofeng; He, Langchong

    2013-11-01

    Cell membrane chromatography (CMC) is a chromatographic biological affinity method that uses specific cell membranes as the stationary phase. In this study, a novel peritoneal macrophage/cell membrane chromatography (PM/CMC)-online-high performance liquid chromatography/mass spectrometry (HPLC/MS) method was established to screen for the anti-inflammatory components from traditional Chinese medicines using hydrocortisone and dexamethasone as standards. The stationary phase of the CMC employed mouse peritoneal macrophage cell membranes. This method was applied to the purification and identification of components in extracts of Chloranthus multistachys Pei. The major component retained by CMC was identified as isofraxidin by HPLC/MS. In vitro experiments revealed that IF was able to inhibit the production of nitric oxide and tumor necrosis factor-α in lipopolysaccharide-stimulated mice and peritoneal macrophages in a dose-dependent manner. The results demonstrated that the PM/CMC-online-HPLC/MS is an effective screening system for the rapid detection, enrichment, and identification of target components from complex samples.

  17. Macrophage Activation by Ursolic and Oleanolic Acids during Mycobacterial Infection.

    PubMed

    López-García, Sonia; Castañeda-Sanchez, Jorge Ismael; Jiménez-Arellanes, Adelina; Domínguez-López, Lilia; Castro-Mussot, Maria Eugenia; Hernández-Sanchéz, Javier; Luna-Herrera, Julieta

    2015-08-06

    Oleanolic (OA) and ursolic acids (UA) are triterpenes that are abundant in vegetables, fruits and medicinal plants. They have been described as active moieties in medicinal plants used for the treatment of tuberculosis. In this study, we analyzed the effects of these triterpenes on macrophages infected in vitro with Mycobacterium tuberculosis (MTB). We evaluated production of nitric oxide (NO), reactive oxygen species (ROS), and cytokines (TNF-α and TGF-β) as well as expression of cell membrane receptors (TGR5 and CD36) in MTB-infected macrophages following treatment with OA and UA. Triterpenes caused reduced MTB growth in macrophages, stimulated production of NO and ROS in the early phase, stimulated TNF-α, suppressed TGF-β and caused over-expression of CD36 and TGR5 receptors. Thus, our data suggest immunomodulatory properties of OA and UA on MTB infected macrophages. In conclusion, antimycobacterial effects induced by these triterpenes may be attributable to the conversion of macrophages from stage M2 (alternatively activated) to M1 (classically activated).

  18. Proatherogenic macrophage activities are targeted by the flavonoid quercetin.

    PubMed

    Lara-Guzman, Oscar J; Tabares-Guevara, Jorge H; Leon-Varela, Yudy M; Álvarez, Rafael M; Roldan, Miguel; Sierra, Jelver A; Londoño-Londoño, Julian A; Ramirez-Pineda, Jose R

    2012-11-01

    Many studies have demonstrated that the flavonoid quercetin protects against cardiovascular disease (CVD) and related risk factors. Atherosclerosis, the underlying cause of CVD, is also attenuated by oral quercetin administration in animal models. Although macrophages are key players during fatty streak formation and plaque progression and aggravation, little is known about the effects of quercetin on atherogenic macrophages. Here, we report that primary bone marrow-derived macrophages internalized less oxidized low-density lipoprotein (oxLDL) and accumulated less intracellular cholesterol in the presence of quercetin. This reduction of foam cell formation correlated with reduced surface expression of the oxLDL receptor CD36. Quercetin also targeted the lipopolysaccharide-dependent, oxLDL-independent pathway of lipid droplet formation in macrophages. In oxLDL-stimulated macrophages, quercetin inhibited reactive oxygen species production and interleukin (IL)-6 secretion. In a system that evaluated cholesterol crystal-induced IL-1β secretion via nucleotide-binding domain and leucine-rich repeat containing protein 3 inflammasome activation, quercetin also exhibited an inhibitory effect. Dyslipidemic apolipoprotein E-deficient mice chronically treated with intraperitoneal quercetin injections had smaller atheromatous lesions, reduced lipid deposition, and less macrophage and T cell inflammatory infiltrate in the aortic roots than vehicle-treated animals. Serum levels of total cholesterol and the lipid peroxidation product malondialdehyde were also reduced in these mice. Our results demonstrate that quercetin interferes with both key proatherogenic activities of macrophages, namely foam cell formation and pro-oxidant/proinflammatory responses, and these effects may explain the atheroprotective properties of this common flavonoid.

  19. The influence of some metabolic inhibitors on phagocytic activity of mouse macrophages in vitro.

    PubMed

    Cifarelli, A; Pepe, G; Paradisi, F; Piccolo, D

    1979-02-06

    The action of different metabolic inhibitors on phagocytosis by macrophages from mouse peritoneal exudate cultured in vitro was studied. The following metabolic inhibitors were tested: sodium iodoacetate, sodium fluoride, sodium fluoroacetate, sodium malonate, 2-4-dinitrophenol, sodium azide, ouabain and cycloheximide, all at the concentration of 10(-3) M. Iodoacetate caused a strong inhibitory effect on phagocytosis; this observation confirms that glycolysis is the main source of energy for the phagocytic process. On the contrary, fluoride, although it is an effective inhibitor of glycolysis, did not exert any effect. This difference may be explained by the fact that sodium fluoride blocks anaerobic glycolysis only in vitro at an unphysiological temperature (0 degrees C). Fluoroacetate and malonate, two compounds which interfere with the Krebs cycle, did not inhibit phagocytosis, but it is known that the Krebs cycle activity is poorly developed in the macrophagic cells. Sodium azide and 2-4-dinitrophenol, two inhibitors of oxidative phosphorylation, showed an effect on phagocytosis only after 3 h of contact with the cell cultures. Ouabain blocks Na+ and K+ transport across the plasma membrane and, probably, it inhibited phagocytosis by interfering with the movements of the cell membrane. Finally, the mode of action of cycloheximide on phagocytosis is uncertain. This compound inhibits the protein synthesis and, perhaps, it can act by preventing the renewal of the cell membrane.

  20. Macrophage Activation and Differentiation Signals Regulate Schlafen-4 Gene Expression: Evidence for Schlafen-4 as a Modulator of Myelopoiesis

    PubMed Central

    van Zuylen, Wendy J.; Garceau, Valerie; Idris, Adi; Schroder, Kate; Irvine, Katharine M.; Lattin, Jane E.; Ovchinnikov, Dmitry A.; Perkins, Andrew C.; Cook, Andrew D.; Hamilton, John A.; Hertzog, Paul J.; Stacey, Katryn J.; Kellie, Stuart; Hume, David A.; Sweet, Matthew J.

    2011-01-01

    Background The ten mouse and six human members of the Schlafen (Slfn) gene family all contain an AAA domain. Little is known of their function, but previous studies suggest roles in immune cell development. In this report, we assessed Slfn regulation and function in macrophages, which are key cellular regulators of innate immunity. Methodology/Principal Findings Multiple members of the Slfn family were up-regulated in mouse bone marrow-derived macrophages (BMM) by the Toll-like Receptor (TLR)4 agonist lipopolysaccharide (LPS), the TLR3 agonist Poly(I∶C), and in disease-affected joints in the collagen-induced model of rheumatoid arthritis. Of these, the most inducible was Slfn4. TLR agonists that signal exclusively through the MyD88 adaptor protein had more modest effects on Slfn4 mRNA levels, thus implicating MyD88-independent signalling and autocrine interferon (IFN)-β in inducible expression. This was supported by the substantial reduction in basal and LPS-induced Slfn4 mRNA expression in IFNAR-1−/− BMM. LPS causes growth arrest in macrophages, and other Slfn family genes have been implicated in growth control. Slfn4 mRNA levels were repressed during macrophage colony-stimulating factor (CSF-1)-mediated differentiation of bone marrow progenitors into BMM. To determine the role of Slfn4 in vivo, we over-expressed the gene specifically in macrophages in mice using a csf1r promoter-driven binary expression system. Transgenic over-expression of Slfn4 in myeloid cells did not alter macrophage colony formation or proliferation in vitro. Monocyte numbers, as well as inflammatory macrophages recruited to the peritoneal cavity, were reduced in transgenic mice that specifically over-expressed Slfn4, while macrophage numbers and hematopoietic activity were increased in the livers and spleens. Conclusions Slfn4 mRNA levels were up-regulated during macrophage activation but down-regulated during differentiation. Constitutive Slfn4 expression in the myeloid lineage in

  1. Dysregulation of Macrophage Activation Profiles by Engineered Nanoparticles

    PubMed Central

    Kodali, Vamsi; Littke, Matthew H.; Tilton, Susan C.; Teeguarden, Justin G.; Shi, Liang; Frevert, Charles W.; Wang, Wei; Pounds, Joel G.; Thrall, Brian D.

    2013-01-01

    Although the potential human health impacts from exposure to engineered nanoparticles (ENPs) are uncertain, past epidemiological studies have established correlations between exposure to ambient air pollution particulates and the incidence of pneumonia and lung infections. Using amorphous silica and superparamagnetic iron oxide (SPIO) as model high production volume ENPs, we examined how macrophage activation by bacterial lipopolysaccharide (LPS) or the lung pathogen Streptococcus pneumoniae is altered by ENP pre-treatment. Neither silica nor SPIO treatment elicited direct cytotoxic or pro-inflammatory effects in bone marrow-derived macrophages. However, pre-treatment of macrophages with SPIO caused extensive reprogramming of nearly 500 genes regulated in response to LPS challenge, hallmarked by exaggerated activation of oxidative stress response pathways and suppressed activation of both pro- and anti-inflammatory pathways. Silica pre-treatment altered regulation of only 67 genes, but there was strong correlation with gene sets affected by SPIO. Macrophages exposed to SPIO displayed a phenotype suggesting an impaired ability to transition from a M1 to M2-like activation state, characterized by suppressed IL-10 induction, enhanced TNFα production, and diminished phagocytic activity toward S. pneumoniae. Studies in macrophages deficient in scavenger receptor A (SR-A) showed SR-A participates in cell uptake of both the ENPs and S. pneumonia, and co-regulates the anti-inflammatory IL-10 pathway. Thus, mechanisms for dysregulation of innate immunity exist by virtue that common receptor recognition pathways are used by some ENPs and pathogenic bacteria, although the extent of transcriptional reprogramming of macrophage function depends on the physicochemical properties of the ENP after internalization. Our results also illustrate that biological effects of ENPs may be indirectly manifested only after challenging normal cell function. Nanotoxicology screening strategies

  2. Dysregulation of Macrophage Activation Profiles by Engineered Nanoparticles

    SciTech Connect

    Kodali, Vamsi; Littke, Matthew H.; Tilton, Susan C.; Teeguarden, Justin G.; Shi, Liang; Frevert, Charles W.; Wang, Wei; Pounds, Joel G.; Thrall, Brian D.

    2013-08-27

    Although the potential human health impacts from exposure to engineered nanoparticles (ENPs) are uncertain, past epidemiological studies have established correlations between exposure to ambient air pollution particulates and the incidence of pneumonia and lung infections. Using amorphous silica and superparamagnetic iron oxide (SPIO) as model high production volume ENPs, we examined how macrophage activation by bacterial lipopolysaccharide (LPS) or the lung pathogen Streptococcus pneumoniae is altered by ENP pretreatment. Neither silica nor SPIO treatment elicited direct cytotoxic or pro-inflammatory effects in bone marrow-derived macrophages. However, pretreatment of macrophages with SPIO caused extensive reprogramming of nearly 500 genes regulated in response to LPS challenge, hallmarked by exaggerated activation of oxidative stress response pathways and suppressed activation of both pro- and anti-inflammatory pathways. Silica pretreatment altered regulation of only 67 genes, but there was strong correlation with gene sets affected by SPIO. Macrophages exposed to SPIO displayed a phenotype suggesting an impaired ability to transition from an M1 to M2-like activation state, characterized by suppressed IL-10 induction, enhanced TNFα production, and diminished phagocytic activity toward S. pneumoniae. Studies in macrophages deficient in scavenger receptor A (SR-A) showed SR-A participates in cell uptake of both the ENPs and S. pneumonia and co-regulates the anti-inflammatory IL-10 pathway. Thus, mechanisms for dysregulation of innate immunity exist by virtue that common receptor recognition pathways are used by some ENPs and pathogenic bacteria, although the extent of transcriptional reprogramming of macrophage function depends on the physicochemical properties of the ENP after internalization. Our results also illustrate that biological effects of ENPs may be indirectly manifested only after challenging normal cell function. Finally, nanotoxicology screening

  3. Inorganic nitrite attenuates NADPH oxidase-derived superoxide generation in activated macrophages via a nitric oxide-dependent mechanism.

    PubMed

    Yang, Ting; Peleli, Maria; Zollbrecht, Christa; Giulietti, Alessia; Terrando, Niccolo; Lundberg, Jon O; Weitzberg, Eddie; Carlström, Mattias

    2015-06-01

    Oxidative stress contributes to the pathogenesis of many disorders, including diabetes and cardiovascular disease. Immune cells are major sources of superoxide (O2(∙-)) as part of the innate host defense system, but exaggerated and sustained O2(∙-) generation may lead to progressive inflammation and organ injuries. Previous studies have proven organ-protective effects of inorganic nitrite, a precursor of nitric oxide (NO), in conditions manifested by oxidative stress and inflammation. However, the mechanisms are still not clear. This study aimed at investigating the potential role of nitrite in modulating NADPH oxidase (NOX) activity in immune cells. Mice peritoneal macrophages or human monocytes were activated by lipopolysaccharide (LPS), with or without coincubation with nitrite. O2(∙-) and peroxynitrite (ONOO(-)) formation were detected by lucigenin-based chemiluminescence and fluorescence techniques, respectively. The intracellular NO production was measured by DAF-FM DA fluorescence. NOX isoforms and inducible NO synthase (iNOS) expression were detected by qPCR. LPS increased both O2(∙-) and ONOO(-) production in macrophages, which was significantly reduced by nitrite (10µmol/L). Mechanistically, the effects of nitrite are (1) linked to increased NO generation, (2) similar to that observed with the NO donor DETA-NONOate, and (3) can be abolished by the NO scavenger carboxy-PTIO or by the xanthine oxidase (XO) inhibitor febuxostat. Nox2 expression was increased in activated macrophages, but was not influenced by nitrite. However, nitrite attenuated LPS-induced upregulation of iNOS expression. Similar to that observed in mice macrophages, nitrite also reduced O2(∙-) generation in LPS-activated human monocytes. In conclusion, XO-mediated reduction of nitrite attenuates NOX activity in activated macrophages, which may modulate the inflammatory response.

  4. Fine-tuning of macrophage activation using synthetic rocaglate derivatives

    PubMed Central

    Bhattacharya, Bidisha; Chatterjee, Sujoy; Devine, William G.; Kobzik, Lester; Beeler, Aaron B.; Porco, John A.; Kramnik, Igor

    2016-01-01

    Drug-resistant bacteria represent a significant global threat. Given the dearth of new antibiotics, host-directed therapies (HDTs) are especially desirable. As IFN-gamma (IFNγ) plays a central role in host resistance to intracellular bacteria, including Mycobacterium tuberculosis, we searched for small molecules to augment the IFNγ response in macrophages. Using an interferon-inducible nuclear protein Ipr1 as a biomarker of macrophage activation, we performed a high-throughput screen and identified molecules that synergized with low concentration of IFNγ. Several active compounds belonged to the flavagline (rocaglate) family. In primary macrophages a subset of rocaglates 1) synergized with low concentrations of IFNγ in stimulating expression of a subset of IFN-inducible genes, including a key regulator of the IFNγ network, Irf1; 2) suppressed the expression of inducible nitric oxide synthase and type I IFN and 3) induced autophagy. These compounds may represent a basis for macrophage-directed therapies that fine-tune macrophage effector functions to combat intracellular pathogens and reduce inflammatory tissue damage. These therapies would be especially relevant to fighting drug-resistant pathogens, where improving host immunity may prove to be the ultimate resource. PMID:27086720

  5. B-cell activation in cats with feline infectious peritonitis (FIP) by FIP-virus-induced B-cell differentiation/survival factors.

    PubMed

    Takano, Tomomi; Azuma, Natsuko; Hashida, Yoshikiyo; Satoh, Ryoichi; Hohdatsu, Tsutomu

    2009-01-01

    It has been suggested that antibody overproduction plays a role in the pathogenesis of feline infectious peritonitis (FIP). However, only a few studies on the B-cell activation mechanism after FIP virus (FIPV) infection have been reported. The present study shows that: (1) the ratio of peripheral blood sIg(+) CD21(-) B-cells was higher in cats with FIP than in SPF cats, (2) the albumin-to-globulin ratio has negative correlation with the ratio of peripheral blood sIg(+) CD21(-) B-cell, (3) cells strongly expressing mRNA of the plasma cell master gene, B-lymphocyte-induced maturation protein 1 (Blimp-1), were increased in peripheral blood in cats with FIP, (4) mRNA expression of B-cell differentiation/survival factors, IL-6, CD40 ligand, and B-cell-activating factor belonging to the tumor necrosis factor family (BAFF), was enhanced in macrophages in cats with FIP, and (5) mRNAs of these B-cell differentiation/survival factors were overexpressed in antibody-dependent enhancement (ADE)-induced macrophages. These data suggest that virus-infected macrophages overproduce B-cell differentiation/survival factors, and these factors act on B-cells and promote B-cell differentiation into plasma cells in FIPV-infected cats.

  6. Relationship between enhanced macrophage phagocytic activity and the induction of interferon by Newcastle disease virus in mice.

    PubMed

    Hamburg, S I; Cassell, G H; Rabinovitch, M

    1980-03-01

    The relationship between phagocytic activity of peritoneal macrophages and serum interferon (IF) titers was evaluated in mice challenged with Newcastle disease virus (NDV). Time course studies indicated peak serum IF titers between 6 and 12 hr, whereas Fc receptor-mediated macrophage phagocytosis was maximal 18 hr after viral administration. Both responses decreased in parallel as the inoculated dose of the virus was reduced. Splenectomy, shown by others to decrease the NDV-induced serum IF titers, significantly decreased the stimulation of phagocytosis. The role of T cells in the response to the virus was studied with nude mice raised under germfree conditions. NDV-induced serum IF titers and macrophage phagocytosis were both diminished in BALB/c nudes compared with their heterozygous littermates. Both responses could be partially restored by transfer of thymocytes obtained from heterozygous mice. The results provide further evidence that in vivo macrophage stimulation by NDV is mediated by induced IF. The experiments with nude mice also indicate that the IF response to NDV is regulated by T lymphocytes.

  7. Response gene to complement 32 protein promotes macrophage phagocytosis via activation of protein kinase C pathway.

    PubMed

    Tang, Rui; Zhang, Gui; Chen, Shi-You

    2014-08-15

    Macrophage phagocytosis plays an important role in host defense. The molecular mechanism, especially factors regulating the phagocytosis, however, is not completely understood. In the present study, we found that response gene to complement 32 (RGC-32) is an important regulator of phagocytosis. Although RGC-32 is induced and abundantly expressed in macrophage during monocyte-macrophage differentiation, RGC-32 appears not to be important for this process because RGC-32-deficient bone marrow progenitor can normally differentiate to macrophage. However, both peritoneal macrophages and bone marrow-derived macrophages with RGC-32 deficiency exhibit significant defects in phagocytosis, whereas RGC-32-overexpressed macrophages show increased phagocytosis. Mechanistically, RGC-32 is recruited to macrophage membrane where it promotes F-actin assembly and the formation of phagocytic cups. RGC-32 knock-out impairs F-actin assembly. RGC-32 appears to interact with PKC to regulate PKC-induced phosphorylation of F-actin cross-linking protein myristoylated alanine-rich protein kinase C substrate. Taken together, our results demonstrate for the first time that RGC-32 is a novel membrane regulator for macrophage phagocytosis.

  8. Activation of p38 MAPK by feline infectious peritonitis virus regulates pro-inflammatory cytokine production in primary blood-derived feline mononuclear cells.

    PubMed

    Regan, Andrew D; Cohen, Rebecca D; Whittaker, Gary R

    2009-02-05

    Feline infectious peritonitis (FIP) is an invariably fatal disease of cats caused by systemic infection with a feline coronavirus (FCoV) termed feline infectious peritonitis virus (FIPV). The lethal pathology associated with FIP (granulomatous inflammation and T-cell lymphopenia) is thought to be mediated by aberrant modulation of the immune system due to infection of cells such as monocytes and macrophages. Overproduction of pro-inflammatory cytokines occurs in cats with FIP, and has been suggested to play a significant role in the disease process. However, the mechanism underlying this process remains unknown. Here we show that infection of primary blood-derived feline mononuclear cells by FIPV WSU 79-1146 and FIPV-DF2 leads to rapid activation of the p38 MAPK pathway and that this activation regulates production of the pro-inflammatory cytokine tumor necrosis factor alpha (TNF-alpha) and interleukin-1 beta (IL-1 beta). FIPV-induced p38 MAPK activation and pro-inflammatory cytokine production was inhibited by the pyridinyl imidazole inhibitors SB 203580 and SC 409 in a dose-dependent manner. FIPV-induced p38 MAPK activation was observed in primary feline blood-derived mononuclear cells individually purified from multiple SPF cats, as was the inhibition of TNF-alpha production by pyridinyl imidazole inhibitors.

  9. Dopamine Receptor Activation Increases HIV Entry into Primary Human Macrophages

    PubMed Central

    Gaskill, Peter J.; Yano, Hideaki H.; Kalpana, Ganjam V.; Javitch, Jonathan A.; Berman, Joan W.

    2014-01-01

    Macrophages are the primary cell type infected with HIV in the central nervous system, and infection of these cells is a major component in the development of neuropathogenesis and HIV-associated neurocognitive disorders. Within the brains of drug abusers, macrophages are exposed to increased levels of dopamine, a neurotransmitter that mediates the addictive and reinforcing effects of drugs of abuse such as cocaine and methamphetamine. In this study we examined the effects of dopamine on HIV entry into primary human macrophages. Exposure to dopamine during infection increased the entry of R5 tropic HIV into macrophages, irrespective of the concentration of the viral inoculum. The entry pathway affected was CCR5 dependent, as antagonizing CCR5 with the small molecule inhibitor TAK779 completely blocked entry. The effect was dose-dependent and had a steep threshold, only occurring above 108 M dopamine. The dopamine-mediated increase in entry required dopamine receptor activation, as it was abrogated by the pan-dopamine receptor antagonist flupenthixol, and could be mediated through both subtypes of dopamine receptors. These findings indicate that the effects of dopamine on macrophages may have a significant impact on HIV pathogenesis. They also suggest that drug-induced increases in CNS dopamine may be a common mechanism by which drugs of abuse with distinct modes of action exacerbate neuroinflammation and contribute to HIV-associated neurocognitive disorders in infected drug abusers. PMID:25268786

  10. Carbon nanohorns allow acceleration of osteoblast differentiation via macrophage activation

    NASA Astrophysics Data System (ADS)

    Hirata, Eri; Miyako, Eijiro; Hanagata, Nobutaka; Ushijima, Natsumi; Sakaguchi, Norihito; Russier, Julie; Yudasaka, Masako; Iijima, Sumio; Bianco, Alberto; Yokoyama, Atsuro

    2016-07-01

    Carbon nanohorns (CNHs), formed by a rolled graphene structure and terminating in a cone, are promising nanomaterials for the development of a variety of biological applications. Here we demonstrate that alkaline phosphatase activity is dramatically increased by coculture of human monocyte derived macrophages (hMDMs) and human mesenchymal stem cells (hMSCs) in the presence of CNHs. CNHs were mainly localized in the lysosome of macrophages more than in hMSCs during coculturing. At the same time, the amount of Oncostatin M (OSM) in the supernatant was also increased during incubation with CNHs. Oncostatin M (OSM) from activated macrophage has been reported to induce osteoblast differentiation and matrix mineralization through STAT3. These results suggest that the macrophages engulfed CNHs and accelerated the differentiation of mesenchymal stem cells into the osteoblast via OSM release. We expect that the proof-of-concept on the osteoblast differentiation capacity by CNHs will allow future studies focused on CNHs as ideal therapeutic materials for bone regeneration.Carbon nanohorns (CNHs), formed by a rolled graphene structure and terminating in a cone, are promising nanomaterials for the development of a variety of biological applications. Here we demonstrate that alkaline phosphatase activity is dramatically increased by coculture of human monocyte derived macrophages (hMDMs) and human mesenchymal stem cells (hMSCs) in the presence of CNHs. CNHs were mainly localized in the lysosome of macrophages more than in hMSCs during coculturing. At the same time, the amount of Oncostatin M (OSM) in the supernatant was also increased during incubation with CNHs. Oncostatin M (OSM) from activated macrophage has been reported to induce osteoblast differentiation and matrix mineralization through STAT3. These results suggest that the macrophages engulfed CNHs and accelerated the differentiation of mesenchymal stem cells into the osteoblast via OSM release. We expect that the

  11. Diet Modifies the Neuroimmune System by Influencing Macrophage Activation

    ERIC Educational Resources Information Center

    Sherry, Christina Lynn

    2009-01-01

    It has long been appreciated that adequate nutrition is required for proper immune function and it is now recognized that dietary components contribute to modulation of immune cells, subsequently impacting the whole body's response during an immune challenge. Macrophage activation plays a critical role in the immune system and directs the…

  12. Proteomic analysis of macrophage activated with salmonella lipopolysaccharide

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Macrophages play pivotal role in immunity. They are activated by many pathogen derived molecules such as lipopolysaccharides (LPS) which trigger the production of various proteins and peptides that drive and resolve inflammation. There are numerous studies on the effect of LPS at the genome level bu...

  13. Regulation of macrophage functions by L-arginine

    PubMed Central

    1989-01-01

    Sites of inflammation with prominent macrophage infiltration, such as wounds and certain tumors, are uniquely deficient in free arginine. The effects of arginine availability on macrophage physiology were investigated. When cultured in media containing less than 0.1 mM L- arginine, rat resident peritoneal macrophages exhibited enhanced spreading, tumor cytotoxicity, superoxide production, phagocytosis, and protein synthesis. Thus, arginine concentrations similar to those found in sites of inflammation can augment macrophage functions, while those found in plasma (approximately 0.1 mM) and in commonly used culture media (0.4 to 1.2 mM) are inhibitory. Culture in homoarginine, but not D-arginine, ornithine, citrulline, urea, histidine, or lysine also inhibited macrophage tumor cytotoxicity, indicating the specificity of the effect. In contrast to resident macrophages, the tumor cytotoxicity of peritoneal macrophages obtained after C. parvum injection was suppressed by culture in arginine-deficient media. However, L-arginine- deficient media enhanced all other activation-associated functions in C. parvum-elicited macrophages as in resident cells. Arginine-free wound fluid promoted resident macrophage tumoricidal activity when compared with rat serum, and again, the addition of L-arginine was inhibitory. The marked effects of L-arginine availability on macrophage functions, together with the knowledge that these cells modify the extracellular arginine concentration in sites of inflammation through arginase, provide evidence for an autoregulatory mechanism of macrophage activation. PMID:2538541

  14. IKKβ Activity Drives Fetal Lung Macrophage Maturation Along a Non-M1/M2 Paradigm

    PubMed Central

    Stouch, Ashley N.; Zaynagetdinov, Rinat; Barham, Whitney J.; Stinnett, Amanda M.; Slaughter, James C.; Yull, Fiona E.; Hoffman, Hal M.; Blackwell, Timothy S.; Prince, Lawrence S.

    2014-01-01

    In preterm infants, exposure to inflammation increases the risk of bronchopulmonary dysplasia, a chronic, developmental lung disease. While macrophages are the key cells that initiate lung inflammation, less is known about lung macrophage phenotype and maturation. We hypothesized that fetal lung macrophages mature into distinct subpopulations during mouse development, and that activation could influence macrophage maturation. Expression of the fetal macrophage markers CD68, CD86, CD206, Ym1, fibrinogen-like protein 2 (FGL2), and indolamine-2, 3-dioxygenase (Ido1) were developmentally regulated, with each marker having different temporal patterns. Flow cytometry analysis showed macrophages within the fetal lung were less diverse than the distinctly separate subpopulations in newborn and adult lungs. Similar to adult alveolar macrophages, fetal lung macrophages responded to the TLR4 agonist LPS and the alternative activation cytokines IL-4 and IL-13. Using a macrophage-specific constitutively active IKKβ transgenic model (IKFM), we demonstrated that macrophage activation increased proinflammatory gene expression and reduced the response of fetal lung macrophages to IL-4 and IL-13. Activation also increased fetal lung macrophage proliferation. Fetal IKFM lungs contained increased percentages of more mature, CD11bloF4/80hi cells that also expressed higher levels of the alternative activation markers CD204 and CD206. Development of fetal lung macrophages into mature alveolar macrophages may therefore include features of both proinflammatory and alternative activation paradigms. PMID:24981452

  15. Modulation of nitric oxide synthase activity in macrophages

    PubMed Central

    Jorens, P. G.; Matthys, K. E.

    1995-01-01

    L-Arginine is converted to the highly reactive and unstable nitric oxide (NO) and L-citrulline by an enzyme named nitric oxide synthase (NOS). NO decomposes into other nitrogen oxides such as nitrite (NO2-) and nitrate (NO2-), and in the presence of superoxide anion to the potent oxidizing agent peroxynitrite (ONOO−). Activated rodent macrophages are capable of expressing an inducible form of this enzyme (iNOS) in response to appropriate stimuli, i.e., lipopolysaccharide (LPS) and interferon-γ (IFNγ). Other cytokines can modulate the induction of NO biosynthesis in macrophages. NO is a major effector molecule of the anti-microbial and cytotoxic activity of rodent macrophages against certain micro-organisms and tumour cells, respectively. The NO synthesizing pathway has been demonstrated in human monocytes and other cells, but its role in host defence seems to be accessory. A delicate functional balance between microbial stimuli, host-derived cytokines and hormones in the microenvironment regulates iNOS expression. This review will focus mainly on the known and proposed mechanisms of the regulation of iNOS induction, and on agents that can modulate NO release once the active enzyme has been expressed in the macrophage. PMID:18475620

  16. Migration Inhibitory Factor and Macrophage Bactericidal Function

    PubMed Central

    Simon, Harvey B.; Sheagren, John N.

    1972-01-01

    A homogeneous population of immunologically active lymphocytes was obtained from peritoneal exudates of guinea pigs with delayed hypersensitivity to bovine gamma globulin (BGG). The lymphocytes were cultured with and without BGG for 24 hr, and cell-free supernatant fluids were then assayed simultaneously for their ability to influence two in vitro parameters of macrophage function: migration from capillary tubes and bactericidal capacity. In four consecutive experiments, supernatants from antigenically stimulated lymphocytes exhibited substantial migration-inhibitory-factor activity without enhancing the ability of macrophages to kill Listeria monocytogenes. Lymphocyte lysates were inactive in both assays. Possible mechanisms of lymphocyte-macrophage interactions are discussed. PMID:4120244

  17. Macrophages make me sick: how macrophage activation states influence sickness behavior.

    PubMed

    Moon, Morgan L; McNeil, Leslie K; Freund, Gregory G

    2011-11-01

    The macrophage (MΦ) is an essential cellular first responder in the innate immune system, sensing, alerting, removing and destroying intrinsic and extrinsic pathogens. While congenital aplasia of granulocytes, T or B lymphocytes leads to serious disease, lack of MΦs is incompatible with life. The MΦ, however, is not a monomorphic entity. These constructers, repairers and defenders of the body are diverse in form and function. What controls MΦ phenotype is beginning to be understood and involves a complex interplay of origination, location and microenvironment. Common to all MΦ developmental pathways are pro-inflammatory and anti-inflammatory cytokines. MΦs respond to these bioactives in distinct ways developing recently recognized activation phenotypes that canonically support bacterial clearance (classical activation), parasite defense/tissue repair (alternative activation) and anti-inflammation (deactivation). Critically, the same cytokines which orchestrate immune defense and homeostasis dramatically impact sense of well being and cognition by eliciting sickness symptoms. Such behaviors are the manifestation of pro/anti-inflammatory cytokine action in the brain and are a direct consequence of MΦ function. This review describes the "new" archetypal MΦ activation states, delineates microglia phenotypic plasticity and explores the importance of these macrophage activation states to sickness behavior.

  18. Pattern of disease after murine hepatitis virus strain 3 infection correlates with macrophage activation and not viral replication.

    PubMed Central

    Pope, M; Rotstein, O; Cole, E; Sinclair, S; Parr, R; Cruz, B; Fingerote, R; Chung, S; Gorczynski, R; Fung, L

    1995-01-01

    Murine hepatitis virus strain (MHV-3) produces a strain-dependent pattern of disease which has been used as a model for fulminant viral hepatitis. This study was undertaken to examine whether there was a correlation between macrophage activation and susceptibility or resistance to MHV-3 infection. Peritoneal macrophages were isolated from resistant A/J and susceptible BALB/cJ mice and, following stimulation with MHV-3 or lipopolysaccharide (LPS), analyzed for transcription of mRNA and production of interleukin-1 (IL-1), tumor necrosis factor alpha (TNF-alpha), transforming growth factor beta (TGF-beta), mouse fibrinogen-like protein (musfiblp), tissue factor (TF), leukotriene B4, and prostaglandin E2 (PGE2). Macrophages from BALB/cJ mice produced greater amounts of IL-1, TNF-alpha, TGF-beta, leukotriene B4, and musfiblp following MHV-3 infection than macrophages from resistant A/J mice, whereas in response to LPS, equivalent amounts of IL-1, TNF-alpha, TGF-beta, and TF were produced by macrophages from both strains of mice. Levels of mRNA of IL-1, TNF-alpha, and musfiblp were greater and more persistent in BALB/cJ than in A/J macrophages, whereas the levels and kinetics of IL-1, TNF-alpha, and TF mRNA following LPS stimulation were identical in macrophages from both strains of mice. Levels of production of PGE2 by MHV-3-stimulated macrophages from resistant and susceptible mice were equivalent; however, the time course for induction of PGE2, differed, but the total quantity of PGE2 produced was insufficient to inhibit induction of musfiblp, a procoagulant known to correlate with development of fulminant hepatic necrosis in susceptible mice. These results demonstrate marked differences in production of inflammatory mediators to MHV-3 infection in macrophages from resistant A/J and susceptible BALB/cJ mice, which may explain the marked hepatic necrosis and fibrin deposition and account for the lethality of MHV-3 in susceptible mice. PMID:7636967

  19. [Murine peritoneal neutrophil activation upon tungsten nanoparticles exposure in vivo].

    PubMed

    Martinova, E A; Baranov, V I

    2014-01-01

    Two examples of tungsten carbide nanoparticles (d = 15 nm, 50 nm) and tungsten carbide nanoparticles with 8% cobalt (d = 50 nm) have been found to induce the neutrophil activation 3 h and 36 h after intraperitoneal administration in the doses 0.005; 0.025; 0.05; 0.25; 0.5; 1; 2.5 and 5 microgram per 1 gram body weight to FVB mice. Neutrophil activation was calculated based on the CD11b and S100 antigen expression. Effect of nanoparticles is bimodal for all tested examples.

  20. Gallium arsenide differentially affects processing of phagolysosomal targeted antigen by macrophages.

    PubMed

    Lewis, T A; Hartmann, C B; McCoy, K L

    1998-03-01

    Gallium arsenide, a semiconductor utilized in the electronics industry, causes immunosuppression in animals. The chemical's effect on macrophages to process antigen for activating pigeon cytochrome-specific helper T cell hybridoma was investigated. Mice were administered 200 mg/kg gallium arsenide or vehicle intraperitoneally. Five-day exposure suppressed processing by splenic macrophages but augmented processing by thioglycollate-elicited and resident peritoneal macrophages. Cytochrome coupled to latex beads was targeted to phagolysosomes to examine processing in lysosomes. Cytochrome beads required phagocytosis for processing and were located in phagolysosomes. Gallium arsenide did not alter the phagocytic ability of macrophages. Peritoneal macrophages normally processed the targeted antigen, indicating that gallium arsenide influenced compartment(s) preceding lysosomes. However, the processing efficiency of exposed splenic macrophages depended on the size of particulate cytochrome, suggesting that processing varied in phagolysosomes of different sizes. Gallium arsenide impacted different intracellular compartments in these macrophages, perhaps contributing to systemic immunotoxicity and local inflammation caused by exposure.

  1. [Pathophysiology of peritonitis].

    PubMed

    Beyer, K; Menges, P; Keßler, W; Heidecke, C-D

    2016-01-01

    Despite intensive research efforts peritonitis leading to subsequent sepsis remains associated with a high mortality. The initial effector cells are the locally residing cells of the peritoneum, such as mesothelial cells, mast cells, macrophages and lymphocytes. Through the secretion of chemokines, an influx of neutrophils initially takes place followed by monocytes. The latter can differentiate into inflammatory macrophages. The non-directed activity of neutrophilic granulocytes is limited by the induction of apoptotic programs. Through the breaching of cytokines, bacteria and microbial products into the circulation, a systemic reaction in the sense of systemic inflammatory response syndrome (SIRS) or sepsis arises. This is viewed as a concomitant derailing of inflammatory as well as anti-inflammatory responses, which leads to extensive apoptosis of lymphocytes. The presentation of apoptotic cells leads to a strong immunosuppression. Due to the coexistence of hyperinflammation and immunosuppression, exact knowledge of the current immune status of the patient is a prerequisite in the development of immunotherapies for the treatment of sepsis.

  2. Role of activated macrophages in experimental Fusarium solani keratitis.

    PubMed

    Hu, Jianzhang; Hu, Yingfeng; Chen, Shikun; Dong, Chenhuan; Zhang, Jingjin; Li, Yanling; Yang, Juan; Han, Xiaoli; Zhu, Xuejun; Xu, Guoxing

    2014-12-01

    Macrophages under the conjunctival tissue are the first line defender cells of the corneas. Elimination of these cells would lead to aggravation of fungal keratitis. To determine how the course of fungal keratitis would be altered after the activation of these macrophages, a murine model was achieved by intrastromal instillation of latex beads before the corneas were infected with Fusarium solani. The keratitis was observed and clinically scored daily. Infected corneas were homogenized for colony counts. The levels of the IL-12, IL-4, MPO, MIF and iNOS cytokines were measured in the corneas using real-time polymerase chain reactions and enzyme-linked immunosorbent assays. CD3+, CD4+ and CD8+ lymphocytes in the corneas, submaxillary lymph nodes and peripheral blood were detected using immunohistochemistry and flow cytometry, respectively. The latex bead-treated mice exhibited aggravated keratitis. Substantially increased macrophage and polymorphonuclear leukocyte infiltration was detected in the corneas, although few colonies were observed. There was a marked increase in the IL-12, IL-4, MPO, MIF and iNOS expression in the corneas. The numbers of CD3+, CD4+ and CD8+ lymphocytes and the CD4+/CD8+ ratio were significantly enhanced in the corneas and submaxillary lymph nodes. However, the number of CD4+ lymphocytes was decreased in the peripheral blood, while the number of CD8+ lymphocytes increased. Collectively, our data demonstrate that the activation of macrophages in the cornea may cause an excessive immune response. Macrophages appear to play a critical role in regulating the immune response to corneal infections with F. solani.

  3. Paricalcitol Reduces Peritoneal Fibrosis in Mice through the Activation of Regulatory T Cells and Reduction in IL-17 Production

    PubMed Central

    González-Mateo, Guadalupe T.; Fernández-Míllara, Vanessa; Bellón, Teresa; Liappas, Georgios; Ruiz-Ortega, Marta; López-Cabrera, Manuel; Selgas, Rafael; Aroeira, Luiz S.

    2014-01-01

    Fibrosis is a significant health problem associated with a chronic inflammatory reaction. The precise mechanisms involved in the fibrotic process are still poorly understood. However, given that inflammation is a major causative factor, immunomodulation is a possible therapeutic approach to reduce fibrosis. The vitamin D receptor (VDR) that is present in all hematopoietic cells has been associated with immunomodulation. We investigated whether the intraperitoneal administration of paricalcitol, a specific activator of the VDR, modulates peritoneal dialysis fluid (PDF)-induced peritoneal fibrosis. We characterized the inflammatory process in the peritoneal cavity of mice treated or not treated with paricalcitol and analyzed the ensuing fibrosis. The treatment reduced peritoneal IL-17 levels, which strongly correlated with a significantly lower peritoneal fibrotic response. In vitro studies demonstrate that both CD4+ and CD8+ regulatory T cells appear to impact the regulation of IL-17. Paricalcitol treatment resulted in a significantly increased frequency of CD8+ T cells showing a regulatory phenotype. The frequency of CD4+ Tregs tends to be increased, but it did not achieve statistical significance. However, paricalcitol treatment increased the number of CD4+ and CD8+ Treg cells in vivo. In conclusion, the activation of immunological regulatory mechanisms by VDR signaling could prevent or reduce fibrosis, as shown in peritoneal fibrosis induced by PDF exposure in mice. PMID:25279459

  4. Studies of macrophage function during Trichinella spiralis infection in mice.

    PubMed Central

    Wing, E J; Krahenbuhl, J L; Remington, J S

    1979-01-01

    Studies were made to investigate the quantitative and functional changes which occur in peritoneal macrophage populations obtained from mice infected orally with Trichinella spiralis larvae. C57BL/6 mice infected with T. spiralis larvae became parasitized with adult worms which were rejected from the intestine from 14 to 20 days after infection. Infected mice developed a striking increase in peritoneal exudate cells, composed largely of macrophages, which was maximal at from 16 to 18 days after infection. T. spiralis larvae and eosinophils were not seen in the peritoneal exudates. Macrophages from mice infected more than 11 days earlier inhibited DNA synthesis of syngeneic and allogeneic tumour cells, a property atributed to activated macrophages. In addition, macrophages from T. spiralis-infected mice had the functional ability to kill EL-4 tumour cells as measured by 51Cr release. Unlike activated macrophages, however, macrophages from infected mice did not develop the ability to inhibit multiplication of the intracellular pathogen Toxoplasma gondii. These studies demonstrate that T. spiralis infection in mice induces changes in macrophage function that differ from changes associated with infections by intracellular pathogens. PMID:437839

  5. Mice Lacking Endoglin in Macrophages Show an Impaired Immune Response

    PubMed Central

    Ojeda-Fernández, Luisa; Recio-Poveda, Lucía; Aristorena, Mikel; Lastres, Pedro; Blanco, Francisco J.; Sanz-Rodríguez, Francisco; Gallardo-Vara, Eunate; de las Casas-Engel, Mateo; Corbí, Ángel; Arthur, Helen M.; Bernabeu, Carmelo; Botella, Luisa M.

    2016-01-01

    Endoglin is an auxiliary receptor for members of the TGF-β superfamily and plays an important role in the homeostasis of the vessel wall. Mutations in endoglin gene (ENG) or in the closely related TGF-β receptor type I ACVRL1/ALK1 are responsible for a rare dominant vascular dysplasia, the Hereditary Hemorrhagic Telangiectasia (HHT), or Rendu-Osler-Weber syndrome. Endoglin is also expressed in human macrophages, but its role in macrophage function remains unknown. In this work, we show that endoglin expression is triggered during the monocyte-macrophage differentiation process, both in vitro and during the in vivo differentiation of blood monocytes recruited to foci of inflammation in wild-type C57BL/6 mice. To analyze the role of endoglin in macrophages in vivo, an endoglin myeloid lineage specific knock-out mouse line (Engfl/flLysMCre) was generated. These mice show a predisposition to develop spontaneous infections by opportunistic bacteria. Engfl/flLysMCre mice also display increased survival following LPS-induced peritonitis, suggesting a delayed immune response. Phagocytic activity is impaired in peritoneal macrophages, altering one of the main functions of macrophages which contributes to the initiation of the immune response. We also observed altered expression of TGF-β1 target genes in endoglin deficient peritoneal macrophages. Overall, the altered immune activity of endoglin deficient macrophages could help to explain the higher rate of infectious diseases seen in HHT1 patients. PMID:27010826

  6. Polydatin Inhibits Formation of Macrophage-Derived Foam Cells

    PubMed Central

    Wu, Min; Liu, Meixia; Guo, Gang; Zhang, Wengao; Liu, Longtao

    2015-01-01

    Rhizoma Polygoni Cuspidati, a Chinese herbal medicine, has been widely used in traditional Chinese medicine for a long time. Polydatin, one of the major active ingredients in Rhizoma Polygoni Cuspidati, has been recently shown to possess extensive cardiovascular pharmacological activities. In present study, we examined the effects of Polydatin on the formation of peritoneal macrophage-derived foam cells in Apolipoprotein E gene knockout mice (ApoE−/−) and explored the potential underlying mechanisms. Peritoneal macrophages were collected from ApoE−/− mice and cultured in vitro. These cells sequentially were divided into four groups: Control group, Model group, Lovastatin group, and Polydatin group. Our results demonstrated that Polydatin significantly inhibits the formation of foam cells derived from peritoneal macrophages. Further studies indicated that Polydatin regulates the metabolism of intracellular lipid and possesses anti-inflammatory effects, which may be regulated through the PPAR-γ signaling pathways. PMID:26557864

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

    PubMed

    Pietrofesa, Ralph A; Velalopoulou, Anastasia; Albelda, Steven M; Christofidou-Solomidou, Melpo

    2016-03-01

    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.

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

    PubMed Central

    Pietrofesa, Ralph A.; Velalopoulou, Anastasia; Albelda, Steven M.; Christofidou-Solomidou, Melpo

    2016-01-01

    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. PMID:26938529

  9. Rickettsia australis Activates Inflammasome in Human and Murine Macrophages

    PubMed Central

    Smalley, Claire; Bechelli, Jeremy; Rockx-Brouwer, Dedeke; Saito, Tais; Azar, Sasha R.; Ismail, Nahed; Walker, David H.; Fang, Rong

    2016-01-01

    Rickettsiae actively escape from vacuoles and replicate free in the cytoplasm of host cells, where inflammasomes survey the invading pathogens. In the present study, we investigated the interactions of Rickettsia australis with the inflammasome in both mouse and human macrophages. R. australis induced a significant level of IL-1β secretion by human macrophages, which was significantly reduced upon treatment with an inhibitor of caspase-1 compared to untreated controls, suggesting caspase-1-dependent inflammasome activation. Rickettsia induced significant secretion of IL-1β and IL-18 in vitro by infected mouse bone marrow-derived macrophages (BMMs) as early as 8–12 h post infection (p.i.) in a dose-dependent manner. Secretion of these cytokines was accompanied by cleavage of caspase-1 and was completely abrogated in BMMs deficient in caspase-1/caspase-11 or apoptosis-associated speck-like protein containing a caspase activation and recruitment domain (ASC), suggesting that R. australis activate the ASC-dependent inflammasome. Interestingly, in response to the same quantity of rickettsiae, NLRP3-/- BMMs significantly reduced the secretion level of IL-1β compared to wild type (WT) controls, suggesting that NLRP3 inflammasome contributes to cytosolic recognition of R. australis in vitro. Rickettsial load in spleen, but not liver and lung, of R. australis-infected NLRP3-/- mice was significantly greater compared to WT mice. These data suggest that NLRP3 inflammasome plays a role in host control of bacteria in vivo in a tissue-specific manner. Taken together, our data, for the first time, illustrate the activation of ASC-dependent inflammasome by R. australis in macrophages in which NLRP3 is involved. PMID:27362650

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

    PubMed

    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.

  11. Role of Chemokines in Shaping Macrophage Activity in AMD.

    PubMed

    Rutar, Matt; Provis, Jan M

    2016-01-01

    Age-related macular degeneration (AMD) is a multifactorial disorder that affects millions of individuals worldwide. While the advent of anti-VEGF therapy has allowed for effective treatment of neovascular 'wet' AMD, no treatments are available to mitigate the more prevalent 'dry' forms of the disease. A role for inflammatory processes in the progression of AMD has emerged over a period of many years, particularly the characterisation of leukocyte infiltrates in AMD-affected eyes, as well as in animal models. This review focuses on the burgeoning understanding of chemokines in the retina, and their potential role in shaping the recruitment and activation of macrophages in AMD. Understanding the mechanisms which promote macrophage activity in the degenerating retina may be key to controlling the potentially devastating consequences of inflammation in diseases such as AMD.

  12. Characterization of mouse peritoneal exudate and associated leukocyte adherence inhibitory activity after intraperitoneal injection of either Bordetella pertussis or Corynebacterium parvum vaccines.

    PubMed Central

    Klein, T W; Pross, S H; Benjamin, W R

    1978-01-01

    Bordetella pertussis and Corynebacterium parvum are commonly used immunopotentiating agents. To explore the inflammatory environment induced by these agents, the peritoneal exudate response in mice following intraperitoneal injection of B. pertussis (PV) and C. parvum (CV) vaccines was investigated. The PV-induced exudate isolated by lavage was characterized by an early neutrophil influx followed by enhanced accumulation of mononuclear cells and fluid protein. The CV exudate was principally mononuclear in nature and displayed fewer numbers of cells and less fluid protein. Both vaccines also enhanced the leukocyte adherence inhibitory activity (LAIA) of peritoneal fluid as measured in vitro. The development of exudate LAIA was T lymphocyte independent. A similar LAIA was demonstrated in nonimmune mouse plasma and serum. Exudate fluid and serum LAIA were heat stable and trypsin sensitive. These studies suggest that significant differences exist in the composition of the local tissue environment following PV and CV injection and that exudate LAIA is serum derived. Further studies in this direction should result in a better understanding of the ways in which inflammatory cells and fluid substances affect lymphocyte-macrophage interaction subsequent to adjuvant administration. PMID:215552

  13. The Impact of Myeloperoxidase and Activated Macrophages on Metaphase II Mouse Oocyte Quality

    PubMed Central

    Shaeib, Faten; Khan, Sana N.; Thakur, Mili; Kohan-Ghadr, Hamid-Reza; Drewlo, Sascha; Saed, Ghassan M.; Pennathur, Subramaniam; Abu-Soud, Husam M.

    2016-01-01

    Myeloperoxidase (MPO), an abundant heme-containing enzyme present in neutrophils, monocytes, and macrophages, is produced in high levels during inflammation, and associated with poor reproductive outcomes. MPO is known to generate hypochlorous acid (HOCl), a damaging reactive oxygen species (ROS) utilizing hydrogen peroxide (H2O2) and chloride (Cl-). Here we investigate the effect of activated immune cells and MPO on oocyte quality. Mouse metaphase II oocytes were divided into the following groups: 1) Incubation with a catalytic amount of MPO (40 nM) for different incubation periods in the presence of 100 mM Cl- with and without H2O2 and with and without melatonin (100 μM), at 37°C (n = 648/648 total number of oocytes in each group for oocytes with and without cumulus cells); 2) Co-cultured with activated mouse peritoneal macrophage and neutrophils cells (1.0 x 106 cells/ml) in the absence and presence of melatonin (200 μM), an MPO inhibitor/ROS scavenger, for different incubation periods in HTF media, at 37°C (n = 200/200); 3) Untreated oocytes incubated for 4 hrs as controls (n = 73/64). Oocytes were then fixed, stained and scored based on the microtubule morphology and chromosomal alignment. All treatments were found to negatively affect oocyte quality in a time dependent fashion as compared to controls. In all cases the presence of cumulus cells offered no protection; however significant protection was offered by melatonin. Similar results were obtained with oocytes treated with neutrophils. This work provides a direct link between MPO and decreased oocyte quality. Therefore, strategies to decrease MPO mediated inflammation may influence reproductive outcomes. PMID:26982351

  14. Antibodies Against Glycolipids Enhance Antifungal Activity of Macrophages and Reduce Fungal Burden After Infection with Paracoccidioides brasiliensis.

    PubMed

    Bueno, Renata A; Thomaz, Luciana; Muñoz, Julian E; da Silva, Cássia J; Nosanchuk, Joshua D; Pinto, Márcia R; Travassos, Luiz R; Taborda, Carlos P

    2016-01-01

    Paracoccidioidomycosis is a fungal disease endemic in Latin America. Polyclonal antibodies to acidic glycosphingolipids (GSLs) from Paracoccidioides brasiliensis opsonized yeast forms in vitro increasing phagocytosis and reduced the fungal burden of infected animals. Antibodies to GSL were active in both prophylactic and therapeutic protocols using a murine intratracheal infection model. Pathological examination of the lungs of animals treated with antibodies to GSL showed well-organized granulomas and minimally damaged parenchyma compared to the untreated control. Murine peritoneal macrophages activated by IFN-γ and incubated with antibodies against acidic GSLs more effectively phagocytosed and killed P. brasiliensis yeast cells as well as produced more nitric oxide compared to controls. The present work discloses a novel target of protective antibodies against P. brasiliensis adding to other well-studied mediators of the immune response to this fungus.

  15. PERITONEAL ABSORPTION

    PubMed Central

    Hahn, P. F.; Miller, L. L.; Robscheit-Robbins, F. S.; Bale, W. F.; Whipple, G. H.

    1944-01-01

    The absorption of red cells from the normal peritoneum of the dog can be demonstrated by means of red cells labeled with radio-iron incorporated in the hemoglobin of these red cells. Absorption in normal dogs runs from 20 to 100 per cent of the amount given within 24 hours. Dogs rendered anemic by bleeding absorb red cells a little less rapidly—ranging from 5 to 80 per cent of the injected red cells. Doubly depleted dogs (anemic and hypoproteinemic) absorb even less in the three experiments recorded. This peritoneal absorption varies widely in different dogs and even in the same dog at different times. We do not know the factors responsible for these variations but there is no question about active peritoneal absorption. The intact red cells pass readily from the peritoneal cavity into lymph spaces in diaphragm and other areas of the peritoneum. The red cells move along the lymphatics and through the lymph glands with little or no phagocytosis and eventually into the large veins through the thoracic ducts. PMID:19871404

  16. Alternative activation of macrophages and pulmonary fibrosis are modulated by scavenger receptor, macrophage receptor with collagenous structure.

    PubMed

    Murthy, Shubha; Larson-Casey, Jennifer L; Ryan, Alan J; He, Chao; Kobzik, Lester; Carter, A Brent

    2015-08-01

    Alternative activation of alveolar macrophages is linked to fibrosis following exposure to asbestos. The scavenger receptor, macrophage receptor with collagenous structure (MARCO), provides innate immune defense against inhaled particles and pathogens; however, a receptor for asbestos has not been identified. We hypothesized that MARCO acts as an initial signaling receptor for asbestos, polarizes macrophages to a profibrotic M2 phenotype, and is required for the development of asbestos-induced fibrosis. Compared with normal subjects, alveolar macrophages isolated from patients with asbestosis express higher amounts of MARCO and have greater profibrotic polarization. Arginase 1 (40-fold) and IL-10 (265-fold) were higher in patients. In vivo, the genetic deletion of MARCO attenuated the profibrotic environment and pulmonary fibrosis in mice exposed to chrysotile. Moreover, alveolar macrophages from MARCO(-/-) mice polarize to an M1 phenotype, whereas wild-type mice have higher Ym1 (>3.0-fold) and nearly 7-fold more active TGF-β1 in bronchoalveolar lavage (BAL) fluid (BALF). Arg(432) and Arg(434) in domain V of MARCO are required for the polarization of macrophages to a profibrotic phenotype as mutation of these residues reduced FIZZ1 expression (17-fold) compared with cells expressing MARCO. These observations demonstrate that a macrophage membrane protein regulates the fibrotic response to lung injury and suggest a novel target for therapeutic intervention.

  17. Comparison of Life Participation Activities Among Adults Treated by Hemodialysis, Peritoneal Dialysis, and Kidney Transplantation: A Systematic Review

    PubMed Central

    Purnell, Tanjala S.; Auguste, Priscilla; Crews, Deidra C.; Lamprea-Montealegre, Julio; Olufade, Temitope; Greer, Raquel; Ephraim, Patti; Sheu, Johanna; Kostecki, Daniel; Powe, Neil R.; Rabb, Hamid; Jaar, Bernard; Boulware, L. Ebony

    2013-01-01

    Background A comprehensive assessment of the association of patients’ renal replacement therapy (RRT) modality on their participation in life activities (physical function, travel, recreation, freedom, work) is needed. Study Design Systematic review of peer-reviewed published studies. Setting & Population Adults undergoing RRT (hemodialysis, peritoneal dialysis, or transplantation). Selection Criteria for Studies We searched PubMed, Cochrane Library, and EMBASE from January 1980 through April 2012 for English-language articles that compared participation in life activities among patients receiving 1) hemodialysis compared with peritoneal dialysis, 2) hemodialysis compared with kidney transplantation, or 3) peritoneal dialysis compared with kidney transplantation. Predictor RRT modality. Outcomes Reported rates of physical function, travel, recreation, freedom, and work-related activities by RRT modality. Results A total of 46 studies (6 prospective cohort, 38 cross-sectional, and 2 pre-post transplantation) provided relevant comparisons of life participation activities among patients treated with hemodialysis, peritoneal dialysis, and kidney transplantation. Studies were conducted from 1985 to 2011 among diverse patient populations in 16 distinct locations. A majority of studies reported greater life participation rates among patients with kidney transplants compared to patients receiving either hemodialysis or peritoneal dialysis. In contrast, a majority of studies reported no differences in outcomes between patients receiving hemodialysis and patients receiving peritoneal dialysis. These results were consistent throughout the study period, across diverse populations, and among the subset of studies that performed appropriate adjustments for potential confounding factors. Limitations Many studies included in the review had significant design weaknesses. Conclusions Evidence suggests patients with kidney transplants may experience better rates of life

  18. RP105 facilitates macrophage activation by Mycobacterium tuberculosis lipoproteins.

    PubMed

    Blumenthal, Antje; Kobayashi, Toshihiko; Pierini, Lynda M; Banaei, Niaz; Ernst, Joel D; Miyake, Kensuke; Ehrt, Sabine

    2009-01-22

    RP105, phylogenetically related to Toll-like receptor (TLR)-4, is reported to facilitate B cell activation by the TLR4-agonist lipopolysaccharide (LPS)--but to limit LPS-induced cytokine production by antigen-presenting cells. Here, we show that the role of RP105 extends beyond LPS recognition and that RP105 positively regulates macrophage responses to Mycobacterium tuberculosis (Mtb) lipoproteins. Mtb-infected RP105(-/-) mice exhibited impaired proinflammatory cytokine responses associated with enhanced bacterial burden and increased lung pathology. The Mtb 19 kDa lipoprotein induced release of tumor necrosis factor in a manner dependent on both TLR2 and RP105, and macrophage activation by Mtb lacking mature lipoproteins was not RP105 dependent. Thus, mycobacterial lipoproteins are RP105 agonists. RP105 physically interacted with TLR2, and both RP105 and TLR2 were required for optimal macrophage activation by Mtb. Our data identify RP105 as an accessory molecule for TLR2, forming part of the receptor complex for innate immune recognition of mycobacterial lipoproteins.

  19. Macrophage-activating lipopeptide-2 exerts protective effects in a murine sepsis model.

    PubMed

    Zeckey, Christian; Tschernig, Thomas; Hildebrand, Frank; Frink, Michael; Frömke, Cornelia; Dorsch, Martina; Krettek, Christian; Barkhausen, Tanja

    2010-06-01

    It is still a major problem to achieve successful therapy in polymicrobial sepsis. Stimulation of the innate immune system via Toll-like receptors (TLRs) 2 and 6 had beneficial effects on chronic inflammatory disorders and a severe peritonitis model when administered 4 days before induction. In the present study, the hypothesis whether the TLR-2 and TLR-6 pathway can also be used as a therapeutic agent parallel to sepsis induction and several hours after the induction was tested. Therefore, the TLR-2 and TLR-6 agonist macrophage-activating lipopeptide 2 (MALP-2) was applied simultaneous to cecal ligation and puncture-sepsis induction and 6 h thereafter. Vehicle-treated animals served as controls. Survival, activity, cytokine levels at different time points, and pulmonary neutrophil infiltration were determined. Improved survival was found after both MALP-2 treatments in comparison with untreated controls. The treatment resulted in reduced monocyte chemotactic protein 1 levels in the plasma; furthermore, pulmonary infiltration by neutrophils was decreased. These results demonstrate a beneficial effect of MALP-2 as a therapeutic agent in polymicrobial sepsis in the cecal ligation and puncture mouse model.

  20. By Homing to the Kidney, Activated Macrophages Potently Exacerbate Renal Injury

    PubMed Central

    Wang, Ying; Wang, Yiping; Cai, Qi; Zheng, Guoping; Lee, Vincent W.S.; Zheng, Dong; Li, Xiaomei; Kui Tan, Thian; Harris, David C.H.

    2008-01-01

    Macrophages are important mediators of injury in most types of human kidney diseases; however, the pathogenic importance of both macrophage number and activation status is unknown. To examine this question, severe-combined immunodeficient mice with adriamycin nephrosis, an experimental model of human focal segmental glomerulosclerosis, were treated intravenously with either resting (1 × 106 to 5 × 106) or activated (1 × 103 to 1 × 106) macrophages on day 6 postadriamycin administration, and the effects on kidney injury were examined. On day 28, renal injury was worse in the group that received activated macrophages at doses as low as 1 × 104 macrophages per mouse compared with control adriamycin nephrotic mice. However, treatment with resting macrophages at doses as high as 5 × 106 macrophages per mouse had no significant effect on either renal histology or function. The transferred activated macrophages homed to inflamed kidneys during the middle-to-late stages of the disease, but such homing was not observed for resting macrophages. This study of in vivo cell adoptive transfer supports the importance of macrophage activation status over macrophage number in causing renal injury. These data suggest that therapeutic strategies for treating progressive kidney diseases should target activated macrophages. PMID:18467704

  1. A Systematic Approach to Identify Markers of Distinctly Activated Human Macrophages

    PubMed Central

    Sudan, Bayan; Wacker, Mark A.; Wilson, Mary E.; Graff, Joel W.

    2015-01-01

    Polarization has been a useful concept for describing activated macrophage phenotypes and gene expression profiles. However, macrophage activation status within tumors and other settings are often inferred based on only a few markers. Complicating matters for relevance to human biology, many macrophage activation markers have been best characterized in mice and sometimes are not similarly regulated in human macrophages. To identify novel markers of activated human macrophages, gene expression profiles for human macrophages of a single donor subjected to 33 distinct activating conditions were obtained and a set of putative activation markers were subsequently evaluated in macrophages from multiple donors using integrated fluidic circuit (IFC)-based RT-PCR. Using unsupervised hierarchical clustering of the microarray screen, highly altered transcripts (>4-fold change in expression) sorted the macrophage transcription profiles into two major and 13 minor clusters. Among the 1874 highly altered transcripts, over 100 were uniquely altered in one major or two related minor clusters. IFC PCR-derived data confirmed the microarray results and determined the kinetics of expression of potential macrophage activation markers. Transcripts encoding chemokines, cytokines, and cell surface were prominent in our analyses. The activation markers identified by this study could be used to better characterize tumor-associated macrophages from biopsies as well as other macrophage populations collected from human clinical samples. PMID:26074920

  2. LPS-Induced Macrophage Activation and Plasma Membrane Fluidity Changes are Inhibited Under Oxidative Stress.

    PubMed

    de la Haba, Carlos; Morros, Antoni; Martínez, Paz; Palacio, José R

    2016-12-01

    Macrophage activation is essential for a correct and efficient response of innate immunity. During oxidative stress membrane receptors and/or membrane lipid dynamics can be altered, leading to dysfunctional cell responses. Our aim is to analyze membrane fluidity modifications and cell function under oxidative stress in LPS-activated macrophages. Membrane fluidity of individual living THP-1 macrophages was evaluated by the technique two-photon microscopy. LPS-activated macrophage function was determined by TNFα secretion. It was shown that LPS activation causes fluidification of macrophage plasma membrane and production of TNFα. However, oxidative stress induces rigidification of macrophage plasma membrane and inhibition of cell activation, which is evidenced by a decrease of TNFα secretion. Thus, under oxidative conditions macrophage proinflammatory response might develop in an inefficient manner.

  3. The E3 ubiquitin ligase neuregulin receptor degradation protein 1 (Nrdp1) promotes M2 macrophage polarization by ubiquitinating and activating transcription factor CCAAT/enhancer-binding Protein β (C/EBPβ).

    PubMed

    Ye, Shuo; Xu, Hongmei; Jin, Jing; Yang, Mingjin; Wang, Chunmei; Yu, Yizhi; Cao, Xuetao

    2012-08-03

    Macrophage activation, including classical (M1) activation and alternative (M2) activation, plays important roles in host immune response and pathogenesis of diseases. Ubiquitination has been shown to be involved in the differentiation of immune cells and in the regulation of immune responses. However, the role of ubiquitination during M1 versus M2 polarization is poorly explored. Here, we showed that arginase 1 (Arg1), a well recognized marker of M2 macrophages, is highly up-regulated in peritoneal macrophages derived from E3 ubiquitin ligase Nrdp1 transgenic (Nrdp1-TG) mice. Furthermore, other M2 feature markers such as MR, Ym1, and Fizz1, as well as Th2 cytokine IL-10, are also up-regulated in Nrdp1-TG macrophages after IL-4 stimulation. Knockdown of Nrdp1 expression effectively inhibits IL-4-induced expression of M2-related genes in macrophages. Moreover, Nrdp1 inhibits LPS-induced production of inducible NOS and pro-inflammatory cytokines TNF-α, IL-1β, and IL-6 in macrophages. Immunoprecipitation assays show that Nrdp1 interacts with and ubiquitinates transcriptional factor C/EBPβ via Lys-63-linked ubiquitination. Nrdp1 enhances C/EBPβ-triggered transcriptional activation of the Arg1 reporter gene in the presence of IL-4 stimulation. Thus, we demonstrate that Nrdp1-mediated ubiquitination and activation of C/EBPβ contributes to a ubiquitin-dependent nonproteolytic pathway that up-regulates Arg1 expression and promotes M2 macrophage polarization.

  4. The E3 Ubiquitin Ligase Neuregulin Receptor Degradation Protein 1 (Nrdp1) Promotes M2 Macrophage Polarization by Ubiquitinating and Activating Transcription Factor CCAAT/Enhancer-binding Protein β (C/EBPβ)*

    PubMed Central

    Ye, Shuo; Xu, Hongmei; Jin, Jing; Yang, Mingjin; Wang, Chunmei; Yu, Yizhi; Cao, Xuetao

    2012-01-01

    Macrophage activation, including classical (M1) activation and alternative (M2) activation, plays important roles in host immune response and pathogenesis of diseases. Ubiquitination has been shown to be involved in the differentiation of immune cells and in the regulation of immune responses. However, the role of ubiquitination during M1 versus M2 polarization is poorly explored. Here, we showed that arginase 1 (Arg1), a well recognized marker of M2 macrophages, is highly up-regulated in peritoneal macrophages derived from E3 ubiquitin ligase Nrdp1 transgenic (Nrdp1-TG) mice. Furthermore, other M2 feature markers such as MR, Ym1, and Fizz1, as well as Th2 cytokine IL-10, are also up-regulated in Nrdp1-TG macrophages after IL-4 stimulation. Knockdown of Nrdp1 expression effectively inhibits IL-4-induced expression of M2-related genes in macrophages. Moreover, Nrdp1 inhibits LPS-induced production of inducible NOS and pro-inflammatory cytokines TNF-α, IL-1β, and IL-6 in macrophages. Immunoprecipitation assays show that Nrdp1 interacts with and ubiquitinates transcriptional factor C/EBPβ via Lys-63-linked ubiquitination. Nrdp1 enhances C/EBPβ-triggered transcriptional activation of the Arg1 reporter gene in the presence of IL-4 stimulation. Thus, we demonstrate that Nrdp1-mediated ubiquitination and activation of C/EBPβ contributes to a ubiquitin-dependent nonproteolytic pathway that up-regulates Arg1 expression and promotes M2 macrophage polarization. PMID:22707723

  5. Immunity to Schistosoma mansoni in guinea-pigs vaccinated with radiation-attenuated cercariae. T-cell activation of macrophages for larval killing.

    PubMed Central

    Gordon, J R; McLaren, D J

    1988-01-01

    This study addresses macrophage activation in guinea-pigs vaccinated with radiation-attenuated cercariae of Schistosoma mansoni. Peritoneal exudate macrophages elicited in vaccinated animals by mineral oil injection were activated to kill larval schistosomes in vitro. Killing efficiency is dependent upon the cell: target ratio employed and is enhanced by, but is not strictly dependent on, the presence of specific antibodies. Macrophages co-cultured with parasites release superoxide radicals and hydrogen peroxide, but the use of inhibitors has shown that neither of these reactive oxygen intermediates are the causal agents of cellular cytotoxicity in this system. Oil-elicited macrophages from naive guinea-pigs do not show comparable activation; they can, however, be activated in vitro by incubation with culture supernatant fluids from schistosome antigen-stimulated spleen, or lymph node cells harvested from vaccinated guinea-pigs. Naive macrophages activated in this way kill schistosomula in vitro and release the activation markers IL-1 and superoxide anion. The macrophage-activating factor (MAF) present in spleen cell culture supernatant fluids has a MW of 35,000-55,000, but does not have the chemical characteristics of gamma-interferon. In this study MAF is shown to be released by a population of lymph node cells that does not adhere to nylon-wool columns, that responds well in proliferation assays to schistosome antigens and to the T-cell mitogen concanavalin A, but does not respond to the B-cell mitogen lipopolysaccharide. These cells have been identified as small lymphocytes. PMID:2832308

  6. Lectin coated MgO nanoparticle: its toxicity, antileishmanial activity, and macrophage activation.

    PubMed

    Jebali, Ali; Hekmatimoghaddam, Seyedhossein; Kazemi, Bahram; Allaveisie, Azra; Masoudi, Alireza; Daliri, Karim; Sedighi, Najme; Ranjbari, Javad

    2014-10-01

    The purpose of this research was to evaluate toxicity of uncoated magnesium oxide nanoparticles (MgO NPs), MgO NPs coated with Peanut agglutinin (PNA) lectin, and PNA alone on the promastigotes of Leishmania major (L. major) and macrophages of BALB/c mice. On the other hand, antileishmanial property of uncoated MgO NPs, lectin coated MgO NPs, and PNA lectin alone was evaluated, and also macrophage activation was investigated after treatment with these materials by measurement of nitrite, H2O2, and some interleukins. This study showed that PNA lectin and lectin coated MgO NPs had approximately no toxicity on L. major and macrophages, but some toxic effects were observed for uncoated MgO NPs, especially at concentration of 500 µg/mL. Interestingly, lectin coated MgO NPs had the highest antileishmanial activity and macrophage activation, compared with uncoated MgO NPs and PNA lectin.

  7. beta-Naphthoflavone protects from peritonitis by reducing TNF-alpha-induced endothelial cell activation.

    PubMed

    Hsu, Sheng-Yao; Liou, Je-Wen; Cheng, Tsung-Lin; Peng, Shih-Yi; Lin, Chi-Chen; Chu, Yuan-Yuan; Luo, Wei-Cheng; Huang, Zheng-Kai; Jiang, Shinn-Jong

    2015-12-01

    β-Naphthoflavone (β-NF), a ligand of the aryl hydrocarbon receptor, has been shown to possess anti-oxidative properties. We investigated the anti-oxidative and anti-inflammatory potential of β-NF in human microvascular endothelial cells treated with tumor necrosis factor-alpha (TNF-α). Pretreatment with β-NF significantly inhibited TNF-α-induced intracellular reactive oxygen species, translocation of p67(phox), and TNF-α-induced monocyte binding and transmigration. In addition, β-NF significantly inhibited TNF-α-induced ICAM-1 and VCAM-1 expression. The mRNA expression levels of the inflammatory cytokines TNF-α and IL-6 were reduced by β-NF, as was the infiltration of white blood cells, in a peritonitis model. The inhibition of adhesion molecules was associated with suppressed nuclear translocation of NF-κB p65 and Akt, and suppressed phosphorylation of ERK1/2 and p38. The translocation of Egr-1, a downstream transcription factor involved in the MEK-ERK signaling pathway, was suppressed by β-NF treatment. Our findings show that β-NF inhibits TNF-α-induced NF-kB and ERK1/2 activation and ROS generation, thereby suppressing the expression of adhesion molecules. This results in reduced adhesion and transmigration of leukocytes in vitro and prevents the infiltration of leukocytes in a peritonitis model. Our findings also suggest that β-NF might prevent TNF-α-induced inflammation.

  8. New insights into the multidimensional concept of macrophage ontogeny, activation and function.

    PubMed

    Ginhoux, Florent; Schultze, Joachim L; Murray, Peter J; Ochando, Jordi; Biswas, Subhra K

    2016-01-01

    Macrophages have protective roles in immunity to pathogens, tissue development, homeostasis and repair following damage. Maladaptive immunity and inflammation provoke changes in macrophage function that are causative of disease. Despite a historical wealth of knowledge about macrophages, recent advances have revealed unknown aspects of their development and function. Following development, macrophages are activated by diverse signals. Such tissue microenvironmental signals together with epigenetic changes influence macrophage development, activation and functional diversity, with consequences in disease and homeostasis. We discuss here how recent discoveries in these areas have led to a multidimensional concept of macrophage ontogeny, activation and function. In connection with this, we also discuss how technical advances facilitate a new roadmap for the isolation and analysis of macrophages at high resolution.

  9. [Hepatic manifestation of a macrophage activation syndrome (MAS)].

    PubMed

    Nagel, Michael; Schwarting, Andreas; Straub, Beate K; Galle, Peter R; Zimmermann, Tim

    2017-04-04

    Background Elevated liver values are the most common pathological laboratory result in Germany. Frequent findings, especially in younger patients, are nutritive- or medicamentous- toxic reasons, viral or autoimmune hepatitis. A macrophage activation syndrome (MAS) may manifest like a viral infectious disease with fever, hepatosplenomegaly and pancytopenia and is associated with a high mortality. It is based on an enhanced activation of macrophages with increased cytokine release, leading to organ damage and multi-organ failure. In addition to genetic causes, MAS is commonly associated with infections and rheumatic diseases. We report the case of a 26-year-old female patient suffering from MAS as a rare cause of elevated liver enzymes. Methods Patient characteristics, laboratory values, liver histology, bone marrow and radiological imaging were documented and analyzed. Case Report After an ordinary upper airway infection with bronchitis, a rheumatic arthritis appeared and was treated with leflunomide und methotrexate. In the further course of the disease, the patient developed an acute hepatitis with fever, pancytopenia and massive hyperferritinemia. Immunohistochemistry of the liver biopsy revealed hemophagocytosis and activation of CD68-positive macrophages. In the radiological and histological diagnostics of the liver and bone marrow, an MAS was diagnosed as underlying disease of the acute hepatitis. Under therapy with prednisolone, the fever disappeared and transaminases and ferritin rapidly normalized. Conclusion Aside from the frequent causes of elevated liver values in younger patients, such as nutritive toxic, drug induced liver injury, viral or autoimmune hepatitis, especially in case of massive hyperferritinemia, a MAS should be considered as a rare cause of acute liver disease.

  10. Control of macrophage metabolism and activation by mTOR and Akt signaling

    PubMed Central

    Covarrubias, Anthony J.; Aksoylar, H. Ibrahim; Horng, Tiffany

    2015-01-01

    Macrophages are pleiotropic cells that assume a variety of functions depending on their tissue of residence and tissue state. They maintain homeostasis as well as coordinate responses to stresses such as infection and metabolic challenge. The ability of macrophages to acquire diverse, context-dependent activities requires their activation (or polarization) to distinct functional states. While macrophage activation is well understood at the level of signal transduction and transcriptional regulation, the metabolic underpinnings are poorly understood. Importantly, emerging studies indicate that metabolic shifts play a pivotal role in control of macrophage activation and acquisition of context-dependent effector activities. The signals that drive macrophage activation impinge on metabolic pathways, allowing for coordinate control of macrophage activation and metabolism. Here we discuss how mTOR and Akt, major metabolic regulators and targets of such activation signals, control macrophage metabolism and activation. Dysregulated macrophage activities contribute to many diseases, including infectious, inflammatory, and metabolic diseases and cancer, thus a better understanding of metabolic control of macrophage activation could pave the way to the development of new therapeutic strategies. PMID:26360589

  11. Control of macrophage metabolism and activation by mTOR and Akt signaling.

    PubMed

    Covarrubias, Anthony J; Aksoylar, H Ibrahim; Horng, Tiffany

    2015-08-01

    Macrophages are pleiotropic cells that assume a variety of functions depending on their tissue of residence and tissue state. They maintain homeostasis as well as coordinate responses to stresses such as infection and metabolic challenge. The ability of macrophages to acquire diverse, context-dependent activities requires their activation (or polarization) to distinct functional states. While macrophage activation is well understood at the level of signal transduction and transcriptional regulation, the metabolic underpinnings are poorly understood. Importantly, emerging studies indicate that metabolic shifts play a pivotal role in control of macrophage activation and acquisition of context-dependent effector activities. The signals that drive macrophage activation impinge on metabolic pathways, allowing for coordinate control of macrophage activation and metabolism. Here we discuss how mTOR and Akt, major metabolic regulators and targets of such activation signals, control macrophage metabolism and activation. Dysregulated macrophage activities contribute to many diseases, including infectious, inflammatory, and metabolic diseases and cancer, thus a better understanding of metabolic control of macrophage activation could pave the way to the development of new therapeutic strategies.

  12. Effect of low-level laser therapy on the modulation of the mitochondrial activity of macrophages

    PubMed Central

    Souza, Nadhia H. C.; Ferrari, Raquel A. M.; Silva, Daniela F. T.; Nunes, Fabio D.; Bussadori, Sandra K.; Fernandes, Kristianne P. S.

    2014-01-01

    BACKGROUND: Macrophages play a major role among the inflammatory cells that invade muscle tissue following an injury. Low-level laser therapy (LLLT) has long been used in clinical practice to accelerate the muscle repair process. However, little is known regarding its effect on macrophages. OBJECTIVE: This study evaluated the effect of LLLT on the mitochondrial activity (MA) of macrophages. METHOD: J774 macrophages were treated with lipopolysaccharide (LPS) and interferon - gamma (IFN-γ) (activation) for 24 h to simulate an inflammatory process, then irradiated with LLLT using two sets of parameters (780 nm; 70 mW; 3 J/cm2 and 660 nm; 15 mW; 7.5 J/cm2). Non-activated/non-irradiated cells composed the control group. MA was evaluated by the cell mitochondrial activity (MTT) assay (after 1, 3 and 5 days) in three independent experiments. The data were analyzed statistically. RESULTS: After 1 day of culture, activated and 780 nm irradiated macrophages showed lower MA than activated macrophages, but activated and 660 nm irradiated macrophages showed MA similar to activated cells. After 3 days, activated and irradiated (660 nm and 780 nm) macrophages showed greater MA than activated macrophages, and after 5 days, the activated and irradiated (660 nm and 780 nm) macrophages showed similar MA to the activated macrophages. CONCLUSIONS: These results show that 660 nm and 780 nm LLLT can modulate the cellular activation status of macrophages in inflammation, highlighting the importance of this resource and of the correct determination of its parameters in the repair process of skeletal muscle. PMID:25076002

  13. LL-37 Immunomodulatory Activity during Mycobacterium tuberculosis Infection in Macrophages

    PubMed Central

    Torres-Juarez, Flor; Cardenas-Vargas, Albertina; Montoya-Rosales, Alejandra; González-Curiel, Irma; Garcia-Hernandez, Mariana H.; Enciso-Moreno, Jose A.; Hancock, Robert E. W.

    2015-01-01

    Tuberculosis is one of the most important infectious diseases worldwide. The susceptibility to this disease depends to a great extent on the innate immune response against mycobacteria. Host defense peptides (HDP) are one of the first barriers to counteract infection. Cathelicidin (LL-37) is an HDP that has many immunomodulatory effects besides its weak antimicrobial activity. Despite advances in the study of the innate immune response in tuberculosis, the immunological role of LL-37 during M. tuberculosis infection has not been clarified. Monocyte-derived macrophages were infected with M. tuberculosis strain H37Rv and then treated with 1, 5, or 15 μg/ml of exogenous LL-37 for 4, 8, and 24 h. Exogenous LL-37 decreased tumor necrosis factor alpha (TNF-α) and interleukin-17 (IL-17) while inducing anti-inflammatory IL-10 and transforming growth factor β (TGF-β) production. Interestingly, the decreased production of anti-inflammatory cytokines did not reduce antimycobacterial activity. These results are consistent with the concept that LL-37 can modulate the expression of cytokines during mycobacterial infection and this activity was independent of the P2X7 receptor. Thus, LL-37 modulates the response of macrophages during infection, controlling the expression of proinflammatory and anti-inflammatory cytokines. PMID:26351280

  14. Rosiglitazone, a Peroxisome Proliferator-Activated Receptor (PPAR)-γ Agonist, Attenuates Inflammation Via NF-κB Inhibition in Lipopolysaccharide-Induced Peritonitis.

    PubMed

    Zhang, Yun-Fang; Zou, Xun-Liang; Wu, Jun; Yu, Xue-Qing; Yang, Xiao

    2015-12-01

    We assessed the anti-inflammatory effect of peroxisome proliferator-activated receptor (PPAR)-γ agonist, rosiglitazone, in a lipopolysaccharide (LPS)-induced peritonitis rat model. LPS was intraperitoneally injected into rats to establish peritonitis model. Male Sprague-Dawley (SD) rats were assigned to normal saline (the solvent of LPS), LPS, rosiglitazone plus LPS, and rosiglitazone alone. A simple peritoneal equilibrium test was performed with 20 ml 4.25 % peritoneal dialysis fluid. We measured the leukocyte count in dialysate and ultrafiltration volume. Peritoneal membrane histochemical staining was performed, and peritoneal thickness was assessed. CD40 and intercellular adhesion molecule-1 messenger RNA (ICAM-1 mRNA) levels in rat visceral peritoneum were detected by reverse transcription (RT)-PCR. IL-6 in rat peritoneal dialysis effluent was measured using enzyme-linked immunosorbent assay. The phosphorylation of NF-κB-p65 and IκBα was analyzed by Western blot. LPS administration resulted in increased peritoneal thickness and decreased ultrafiltration volume. Rosiglitazone pretreatment significantly decreased peritoneal thickness. In addition to CD40 and ICAM-1 mRNA expression, the IL-6, p-p65, and p-IκBα protein expressions were enhanced in LPS-administered animals. Rosiglitazone pretreatment significantly decreased ICAM-1 mRNA upregulation, secretion of IL-6 protein, and phosphorylation of NF-κB-p65 and IκBα without decreasing CD40 mRNA expression. Rosiglitazone has a protective effect in peritonitis, simultaneously decreasing NF-κB phosphorylation, suggesting that NF-κB signaling pathway mediated peritoneal inflammation induced by LPS. PPAR-γ might be considered a potential therapeutic target against peritonitis.

  15. Macrophages migrate in an activation-dependent manner to chemokines involved in neuroinflammation

    PubMed Central

    2014-01-01

    Background In neuroinflammatory diseases, macrophages can play a dual role in the process of tissue damage, depending on their activation status (M1 / M2). M1 macrophages are considered to exert damaging effects to neurons, whereas M2 macrophages are reported to aid regeneration and repair of neurons. Their migration within the central nervous system may be of critical importance in the final outcome of neurodegeneration in neuroinflammatory diseases e.g. multiple sclerosis (MS). To provide insight into this process, we examined the migratory capacity of human monocyte-derived M1 and M2 polarised macrophages towards chemoattractants, relevant for neuroinflammatory diseases like MS. Methods Primary cultures of human monocyte-derived macrophages were exposed to interferon gamma and lipopolysaccharide (LPS) to evoke proinflammatory (M1) activation or IL-4 to evoke anti-inflammatory (M2) activation. In a TAXIScan assay, migration of M0, M1 and M2 towards chemoattractants was measured and quantified. Furthermore the adhesion capacity and the expression levels of integrins as well as chemokine receptors of M0, M1 and M2 were assessed. Alterations in cell morphology were analysed using fluorescent labelling of the cytoskeleton. Results Significant differences were observed between M1 and M2 macrophages in the migration towards chemoattractants. We show that M2 macrophages migrated over longer distances towards CCL2, CCL5, CXCL10, CXCL12 and C1q compared to non-activated (M0) and M1 macrophages. No differences were observed in the adhesion of M0, M1 and M2 macrophages to multiple matrix components, nor in the expression of integrins and chemokine receptors. Significant changes were observed in the cytoskeleton organization upon stimulation with CCL2, M0, M1 and M2 macrophages adopt a spherical morphology and the cytoskeleton is rapidly rearranged. M0 and M2 macrophages are able to form filopodia, whereas M1 macrophages only adapt a spherical morphology. Conclusions

  16. Macrophage activation syndrome in the course of monogenic autoinflammatory disorders.

    PubMed

    Rigante, Donato; Emmi, Giacomo; Fastiggi, Michele; Silvestri, Elena; Cantarini, Luca

    2015-08-01

    An overwhelming activation of cytotoxic T cells and well-differentiated macrophages leading to systemic overload of inflammatory mediators characterizes the so-called macrophage activation syndrome (MAS); this potentially life-threatening clinical entity may derive from several genetic defects involved in granule-mediated cytotoxicity but has been largely observed in patients with juvenile idiopathic arthritis, many rheumatologic diseases, infections, and malignancies. The occurrence of MAS in the natural history or as the revealing clue of monogenic autoinflammatory disorders (AIDs), rare conditions caused by disrupted innate immunity pathways with overblown release of proinflammatory cytokines, has been only reported in few isolated patients with cryopyrin-associated periodic syndrome, mevalonate kinase deficiency, familial Mediterranean fever, and tumor necrosis factor receptor-associated periodic syndrome since 2001. All these patients displayed various clinical, laboratory, and histopathologic features of MAS and have often required intensive care support. Only one patient has died due to MAS. Defective cytotoxic cell function was documented in a minority of patients. Corticosteroids were the first-line treatment, but anakinra was clinically effective in three refractory cases. Even if MAS and AIDs share multiple clinical features as well as heterogeneous pathogenetic scenes and a potential response to anti-interleukin-1 targeted therapies, MAS requires a prompt specific recognition in the course of AIDs due to its profound severity and high mortality rate.

  17. Macrophage immunomodulatory activity of polysaccharides isolated from Opuntia polyacantha

    PubMed Central

    Schepetkin, Igor A.; Xie, Gang; Kirpotina, Liliya N.; Klein, Robyn A.; Jutila, Mark A.; Quinn, Mark T.

    2008-01-01

    Opuntia polyacantha (prickly pear cactus) has been used extensively for its nutritional properties; however, less is known regarding medicinal properties of Opuntia tissues. In the present study, we extracted polysaccharides from O. polyacantha and used size-exclusion chromatography to fractionate the crude polysaccharides into four polysaccharide fractions (designated as Opuntia polysaccharides C-I to C-IV). The average Mr of fractions C-I through C-IV was estimated to be 733, 550, 310, and 168 kDa, respectively, and sugar composition analysis revealed that Opuntia polysaccharides consisted primarily of galactose, galacturonic acid, xylose, arabinose, and rhamnose. Analysis of the effects of Opuntia polysaccharides on human and murine macrophages demonstrated that all four fractions had potent immunomodulatory activity, inducing production of reactive oxygen species, nitric oxide, tumor necrosis factor α, and interleukin 6. Furthermore, modulation of macrophage function by Opuntia polysaccharides was mediated, at least in part, through activation of nuclear factor κB. Together, our results provide a molecular basis to explain a portion of the beneficial therapeutic properties of extracts from O. polyacantha and support the concept of using Opuntia polysaccharides as an immunotherapeutic adjuvant. PMID:18597716

  18. Macrophage immunomodulatory activity of polysaccharides isolated from Opuntia polyacantha.

    PubMed

    Schepetkin, Igor A; Xie, Gang; Kirpotina, Liliya N; Klein, Robyn A; Jutila, Mark A; Quinn, Mark T

    2008-10-01

    Opuntia polyacantha (prickly pear cactus) has been used extensively for its nutritional properties; however, less is known regarding medicinal properties of Opuntia tissues. In the present study, we extracted polysaccharides from O. polyacantha and used size-exclusion chromatography to fractionate the crude polysaccharides into four polysaccharide fractions (designated as Opuntia polysaccharides C-I to C-IV). The average M(r) of fractions C-I through C-IV was estimated to be 733, 550, 310, and 168 kDa, respectively, and sugar composition analysis revealed that Opuntia polysaccharides consisted primarily of galactose, galacturonic acid, xylose, arabinose, and rhamnose. Analysis of the effects of Opuntia polysaccharides on human and murine macrophages demonstrated that all four fractions had potent immunomodulatory activity, inducing production of reactive oxygen species, nitric oxide, tumor necrosis factor alpha, and interleukin 6. Furthermore, modulation of macrophage function by Opuntia polysaccharides was mediated, at least in part, through activation of nuclear factor kappaB. Together, our results provide a molecular basis to explain a portion of the beneficial therapeutic properties of extracts from O. polyacantha and support the concept of using Opuntia polysaccharides as an immunotherapeutic adjuvant.

  19. Macrophage origin limits functional plasticity in helminth-bacterial co-infection

    PubMed Central

    Campbell, Sharon M.; Duncan, Sheelagh; Hewitson, James P.; Barr, Tom A.; Jackson-Jones, Lucy H.; Maizels, Rick M.

    2017-01-01

    Rapid reprogramming of the macrophage activation phenotype is considered important in the defense against consecutive infection with diverse infectious agents. However, in the setting of persistent, chronic infection the functional importance of macrophage-intrinsic adaptation to changing environments vs. recruitment of new macrophages remains unclear. Here we show that resident peritoneal macrophages expanded by infection with the nematode Heligmosomoides polygyrus bakeri altered their activation phenotype in response to infection with Salmonella enterica ser. Typhimurium in vitro and in vivo. The nematode-expanded resident F4/80high macrophages efficiently upregulated bacterial induced effector molecules (e.g. MHC-II, NOS2) similarly to newly recruited monocyte-derived macrophages. Nonetheless, recruitment of blood monocyte-derived macrophages to Salmonella infection occurred with equal magnitude in co-infected animals and caused displacement of the nematode-expanded, tissue resident-derived macrophages from the peritoneal cavity. Global gene expression analysis revealed that although nematode-expanded resident F4/80high macrophages made an anti-bacterial response, this was muted as compared to newly recruited F4/80low macrophages. However, the F4/80high macrophages adopted unique functional characteristics that included enhanced neutrophil-stimulating chemokine production. Thus, our data provide important evidence that plastic adaptation of MΦ activation does occur in vivo, but that cellular plasticity is outweighed by functional capabilities specific to the tissue origin of the cell. PMID:28334040

  20. STAT1 signaling within macrophages is required for antifungal activity against Cryptococcus neoformans.

    PubMed

    Leopold Wager, Chrissy M; Hole, Camaron R; Wozniak, Karen L; Olszewski, Michal A; Mueller, Mathias; Wormley, Floyd L

    2015-12-01

    Cryptococcus neoformans, the predominant etiological agent of cryptococcosis, is an opportunistic fungal pathogen that primarily affects AIDS patients and patients undergoing immunosuppressive therapy. In immunocompromised individuals, C. neoformans can lead to life-threatening meningoencephalitis. Studies using a virulent strain of C. neoformans engineered to produce gamma interferon (IFN-γ), denoted H99γ, demonstrated that protection against pulmonary C. neoformans infection is associated with the generation of a T helper 1 (Th1)-type immune response and signal transducer and activator of transcription 1 (STAT1)-mediated classical (M1) macrophage activation. However, the critical mechanism by which M1 macrophages mediate their anti-C. neoformans activity remains unknown. The current studies demonstrate that infection with C. neoformans strain H99γ in mice with macrophage-specific STAT1 ablation resulted in severely increased inflammation of the pulmonary tissue, a dysregulated Th1/Th2-type immune response, increased fungal burden, deficient M1 macrophage activation, and loss of protection. STAT1-deficient macrophages produced significantly less nitric oxide (NO) than STAT1-sufficient macrophages, correlating with an inability to control intracellular cryptococcal proliferation, even in the presence of reactive oxygen species (ROS). Furthermore, macrophages from inducible nitric oxide synthase knockout mice, which had intact ROS production, were deficient in anticryptococcal activity. These data indicate that STAT1 activation within macrophages is required for M1 macrophage activation and anti-C. neoformans activity via the production of NO.

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

    SciTech Connect

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

    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.

  2. Prostaglandin D2-loaded microspheres effectively activate macrophage effector functions.

    PubMed

    Pereira, Priscilla Aparecida Tartari; Bitencourt, Claudia da Silva; dos Santos, Daiane Fernanda; Nicolete, Roberto; Gelfuso, Guilherme Martins; Faccioli, Lúcia Helena

    2015-10-12

    Biodegradable lactic-co-glycolic acid (PLGA) microspheres (MS) improve the stability of biomolecules stability and allow enable their sustained release. Lipid mediators represent a strategy for improving host defense; however, most of these mediators, such as prostaglandin D2 (PGD2), have low water solubility and are unstable. The present study aimed to develop and characterize MS loaded with PGD2 (PGD2-MS) to obtain an innovative tool to activate macrophages. PGD2-MS were prepared using an oil-in-water emulsion solvent extraction-evaporation process, and the size, zeta potential, surface morphology and encapsulation efficiency were determined. It was also evaluated in vitro the phagocytic index, NF-κB activation, as well as nitric oxide and cytokine production by alveolar macrophages (AMs) in response to PGD2-MS. PGD2-MS were spherical with a diameter of 5.0±3.3 μm and regular surface, zeta potential of -13.4±5.6 mV, and 36% of encapsulation efficiency, with 16-26% release of entrapped PGD2 at 4 and 48 h, respectively. PGD2-MS were more efficiently internalized by AMs than unloaded-MS, and activated NF-κB more than free PGD2. Moreover, PGD2-MS stimulated the production of nitric oxide, TNF-α, IL-1β, and TGF-β, more than free PGD2, indicating that microencapsulation increased the activating effect of PGD2 on cells. In LPS-pre-treated AMs, PGD2-MS decreased the release of IL-6 but increased the production of nitric oxide and IL-1β. These results show that the morphological characteristics of PGD2-MS facilitated interaction with, and activation of phagocytic cells; moreover, PGD2-MS retained the biological activities of PGD2 to trigger effector mechanisms in AMs. It is suggested that PGD2-MS represent a strategy for therapeutic intervention in the lungs of immunocompromised subjects.

  3. Interaction of human leukocytes and Entamoeba histolytica. Killing of virulent amebae by the activated macrophage.

    PubMed Central

    Salata, R A; Pearson, R D; Ravdin, J I

    1985-01-01

    Capable effector mechanisms in the human immune response against the cytolytic, protozoan parasite Entamoeba histolytica have not been described. To identify a competent human effector cell, we studied the in vitro interactions of normal human polymorphonuclear neutrophils, peripheral blood mononuclear cells (PBMC), monocytes (MC), and MC-derived macrophages with virulent axenic amebae (strain HMI-IMSS). Amebae killed neutrophils, PBMC, MC, and MC-derived macrophages (P less than 0.001), without loss of parasite viability. The addition of heat-inactivated immune serum did not enable leukocytes to kill amebae, nor did it protect these host cells from amebae. MC-derived macrophages, activated with lymphokine elicited by the mitogens conconavalin A, phytohemagglutinin, or an amebic soluble protein preparation (strain HK9), killed 55% of amebae by 3 h in a trypan blue exclusion assay (P less than 0.001); during this time, 40% of the activated macrophages died. Lysis of amebae was confirmed using 111Indium oxine radiolabeled parasites and was antibody independent. Macrophage death appeared to be due to the deleterious effect of lysed amebae rather than the contact-dependent effector mechanisms of E. histolytica. Adherence between activated macrophages and amebae was greater than that between other leukocytes and amebae (P less than 0.001). Microscopic observations, kinetic analysis of the killing of amebae by activated macrophages, and suspension of amebae with adherent activated macrophages in a 10% dextran solution indicated that contact by activated macrophages was necessary to initiate the killing of amebae. Catalase but not superoxide dismutase inhibited the amebicidal capacity of activated macrophages (P less than 0.001). However, activated macrophages from an individual with chronic granulomatous disease were able to kill amebae, but not as effectively as normal cells (P less than 0.01). In summary, activated MC-derived macrophages killed virulent E. histolytica

  4. Maps of Ventricular Activation Time (VAT) Differences in Children on Peritoneal Dialysis — a Pilot Study

    PubMed Central

    Laszki-Szcząchor, Krystyna; Polak-Jonkisz, Dorota; Zwolińska, Danuta; Salomon, Ewa; Filipowski, Henryk; Sobieszczańska, Małgorzata

    2015-01-01

    ♦ Background: Decrement of glomerular filtration rate leads to many serious complications that cause both functional and structural impairments of the other organs. Long-term clinical observations of children and teenagers with end-stage renal disease (ESRD) showed that more than one third of those patients manifested various cardio-vascular conditions. The aim of the study was to analyze possible disturbances in the heart ventricular conduction system by using a technique of ventricular activation time (VAT) differences in ESRF children on peritoneal dialysis (PD) with normal electrocardiogram (ECG) examinations. ♦ Material and methods: The study group comprised 10 ESRD children (mean age: 13.6 ± 2.31 years) on peritoneal dialysis – group I. The control group (group II) consisted of 26 age-matched healthy children with no clinical evidence of renal or cardiac disease and with normal 12-lead ECG recordings. Each of the ESRD patients was also subjected to the standard ECG examination. In order to capture possible heart conduction abnormalities, body surface potential mapping (BSPM) recordings were performed in PD patients between the successive dwells (‘on empty abdomen’) with a HPM-7100 Fukuda Denshi system. Based on the source ECG data, the original technique of a VAT difference map was then applied. ♦ Results: Differences between VAT values for the two examined groups of children, controls and ESRD patients on PD, were significantly pronounced in the region of the right upper anterior thorax, the entire left thorax and nearly in the total back. Such a pattern of VAT delays indicates a pathological electric transmission in the intraventricular conduction system of the left anterior fascicle of His bundle. ♦ Conclusion: 1. VAT maps (isochrone maps) can be useful to detect abnormal spreading and depolarization through the heart ventricles. 2. Map of VAT value differences makes it possible to identify early disturbances in the left His bundle branch in

  5. HMGB1 enhances the protumoral activities of M2 macrophages by a RAGE-dependent mechanism.

    PubMed

    Rojas, Armando; Delgado-López, Fernando; Perez-Castro, Ramón; Gonzalez, Ileana; Romero, Jacqueline; Rojas, Israel; Araya, Paulina; Añazco, Carolina; Morales, Erik; Llanos, Jorge

    2016-03-01

    The monocyte-macrophage lineage shows a high degree of diversity and plasticity. Once they infiltrate tissues, they may acquire two main functional phenotypes, being known as the classically activated type 1 macrophages (M1) and the alternative activated type 2 macrophages (M2). The M1 phenotype can be induced by bacterial products and interferon-γ and exerts a cytotoxic effect on cancer cells. Conversely, the alternatively activated M2 phenotype is induced by Il-4/IL13 and promotes tumor cell growth and vascularization. Although receptor for advanced glycation end-products (RAGE) engagement in M1 macrophages has been reported by several groups to promote inflammation, nothing is known about the functionality of RAGE in M2 macrophages. In the current study, we demonstrate that RAGE is equally expressed in both macrophage phenotypes and that RAGE activation by high-mobility group protein box1 (HMGB1) promotes protumoral activities of M2 macrophages. MKN45 cells co-cultured with M2 macrophages treated with HMGB1 at different times displayed higher invasive abilities. Additionally, conditioned medium from HMGB1-treated M2 macrophages promotes angiogenesis in vitro. RAGE-targeting knockdown abrogates these activities. Overall, the present findings suggest that HMGB1 may contribute, by a RAGE-dependent mechanism, to the protumoral activities of the M2 phenotype.

  6. Low-power laser irradiation enhance macrophage phagocytic capacity through Src activation

    NASA Astrophysics Data System (ADS)

    Wu, Shengnan; Zhou, Feifan; Xing, Da

    2012-03-01

    Phagocytosis and subsequent degradation of pathogens by macrophages play a pivotal role in host innate immunity in mammals. Laser irradiation has been found to produce photobiological effects with evidence of interference with organic functions. In this study, we focused our attention on the effects of He-Ne laser on the phagocytic activity of macrophages, the regulation mechanism of phagocytosis was also discussed. Our results indicated that Low-power laser irradiation can enhance the phagocytosis of macrophage through activation of Src.

  7. Purification, cloning, and functional characterization of a novel immunomodulatory protein from Antrodia camphorata (bitter mushroom) that exhibits TLR2-dependent NF-κB activation and M1 polarization within murine macrophages.

    PubMed

    Sheu, Fuu; Chien, Po-Jung; Hsieh, Kuang-Yang; Chin, Kah-Lock; Huang, Wan-Ting; Tsao, Chiao-Yin; Chen, Yin-Fang; Cheng, Hui-Chung; Chang, Hui-Hsin

    2009-05-27

    A new immunomodulatory protein, designated ACA, was purified from the mycelium extract of Antrodia camphorata , a well-known folk medicine bitter mushroom in Taiwan, and N-terminally sequenced. By taking advantage of its N-terminal amino acid sequence, the full-length ACA gene was cloned using rapid amplification of cDNA ends (RACE) approach. This gene encodes a 136 amino acid protein that is homologous to the phytotoxic proteins from fungi. On the basis of the data of N-terminal sequencing and N-glycosidase F treatment, the native ACA was confirmed to be a glycoprotein. The similarity in activation of TLR4-deficient macrophages by both the native ACA and recombinant ACA (rACA) suggested that the glycosyl group(s) of the native ACA was insignificant in macrophage activation. Moreover, the failure of rACA to induce TLR2-deficient macrophages and to activate the RAW 264.7 macrophages transfected with the dominate-negative MyD88 (dnMyD88) indicated that the ACA-mediated macrophage activation was TLR2/MyD88 dependent. Microarray assay of the ACA-activated NFκB-related gene expression showed that rACA demonstrated a LPS-mimetic proinflammatory response toward RAW 264.7 macrophages. Furthermore, rACA enhanced phagocytosis activity and CD86 (B7-2) expression as well as induced TNF-α and IL-1β production within murine peritoneal macrophages. A time-dependent induction of mRNA expression of cytokines TNF-α, IL-1β, IL-6, and IL-12 as well as chemokines CCL3, CCL4, CCL5, and CCL10, but not IL-10, CCL17, CCL22, and CCL24, was observed after the ACA treatment of the macrophages. These results proposed that ACA exhibited M1 polarization and differentiation in macrophages. Thus, ACA is an important immunomodulatory protein of A. camphorata.

  8. Angiopoietin-like protein 2 induces proinflammatory responses in peritoneal cells

    PubMed Central

    Umikawa, Masato; Umikawa, Asako; Asato, Tsuyoshi; Takei, Kimiko; Matsuzaki, Goro; Kariya, Ken-ichi; Zhang, Cheng Cheng

    2015-01-01

    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 elavated 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. PMID:26435501

  9. Iron modulates the replication of virulent Mycobacterium bovis in resting and activated bovine and possum macrophages.

    PubMed

    Denis, Michel; Buddle, Bryce M

    2005-09-15

    Bovine and possum macrophages were infected in vitro with a virulent strain of Mycobacterium bovis, and mycobacterial replication was measured in the infected macrophages cultured under a variety of conditions. Virulent M. bovis replicated substantially in alveolar possum macrophages as well as in bovine blood monocyte-derived macrophages. Addition of recombinant bovine interferon-gamma (IFN-gamma) with low concentrations of lipopolysaccharide (LPS) rendered bovine macrophages significantly more resistant to M. bovis replication. Disruption of iron levels in infected macrophages by addition of apotransferrin or bovine lactoferrin blocked replication of M. bovis in both bovine and possum macrophages. On the other hand, addition of exogenous iron, either in the form of iron citrate or iron-saturated transferrin, rendered macrophages of both species much more permissive for the replication of M. bovis. The impact of iron deprivation/loading on the mycobacteriostatic activity of cells was independent of nitric-oxide release, as well as independent of the generation of oxygen radical species in both possum and bovine macrophages. Exogenous iron was shown to reverse the ability of IFN-gamma/LPS pulsed bovine macrophages to restrict M. bovis replication. When autologous possum lymphocytes from animals vaccinated with M. bovis strain BCG were added to infected macrophages, they rendered the macrophages less permissive for virulent M. bovis replication. Loading the cells with iron prior to this macrophage-lymphocyte interaction, reversed this immune effect induced by sensitized cells. We conclude that, in two important animal species, intracellular iron level plays an important role in M. bovis replication in macrophages, irrespective of their activation status.

  10. Phagocyte respiratory burst activates macrophage erythropoietin signalling to promote acute inflammation resolution

    PubMed Central

    Luo, Bangwei; Wang, Jinsong; Liu, Zongwei; Shen, Zigang; Shi, Rongchen; Liu, Yu-Qi; Liu, Yu; Jiang, Man; Wu, Yuzhang; Zhang, Zhiren

    2016-01-01

    Inflammation resolution is an active process, the failure of which causes uncontrolled inflammation which underlies many chronic diseases. Therefore, endogenous pathways that regulate inflammation resolution are fundamental and of wide interest. Here, we demonstrate that phagocyte respiratory burst-induced hypoxia activates macrophage erythropoietin signalling to promote acute inflammation resolution. This signalling is activated following acute but not chronic inflammation. Pharmacological or genetical inhibition of the respiratory burst suppresses hypoxia and macrophage erythropoietin signalling. Macrophage-specific erythropoietin receptor-deficient mice and chronic granulomatous disease (CGD) mice, which lack the capacity for respiratory burst, display impaired inflammation resolution, and exogenous erythropoietin enhances this resolution in WT and CGD mice. Mechanistically, erythropoietin increases macrophage engulfment of apoptotic neutrophils via PPARγ, promotes macrophage removal of debris and enhances macrophage migration to draining lymph nodes. Together, our results provide evidences of an endogenous pathway that regulates inflammation resolution, with important implications for treating inflammatory conditions. PMID:27397585

  11. Pseuderanthemum palatiferum leaf extract inhibits the proinflammatory cytokines, TNF-α and IL-6 expression in LPS-activated macrophages.

    PubMed

    Sittisart, Patcharawan; Chitsomboon, Benjamart; Kaminski, Norbert E

    2016-11-01

    The anti-inflammatory potential and underlying mechanisms of an ethanol extract of Pseuderanthemum palatiferum (EEP) leaves was investigated using LPS-activated macrophages. Our results show EEP produced a concentration-dependent suppression of TNF-α and IL-6 secretion by LPS-activated mouse peritoneal macrophages. EEP also suppressed LPS-induced TNF-α and IL-6 protein and mRNA levels in mouse-derived myeloid cell line RAW264.7. To further elucidate the molecular mechanisms responsible for impaired TNF-α and IL-6 regulation by EEP, the activation of transcription factors, NF-κB, C/EBP, and AP-1, was monitored using electrophoretic mobility shift assays. EEP suppressed LPS-induced NF-κB DNA binding activity within both the TNF-α and IL-6 promoters in RAW264.7 cells with impairment being more pronounced in the IL-6 promoter. In addition, EEP exhibited a concentration-dependent suppression of C/EBP and AP-1 DNA binding activity within the IL-6 promoter. Concordantly, IL-6 luciferase promoter reporter activity was also suppressed by EEP in transiently transfected RAW264.7 cells, upon LPS activation. EEP analysis by GC-MS and HPLC DAD-MSD revealed the presence of β-sitosterol and various polyphenols, respectively, which are known to possess anti-inflammatory activity. Collectively, these results suggest that the anti-inflammatory effects of EEP are mediated, at least in part, by modulating TNF-α and IL-6 expression through impairment of NF-κB, C/EBP, and AP-1 activity.

  12. The use of microelectrode array (MEA) to study rat peritoneal mast cell activation.

    PubMed

    Yeung, Chi-Kong; Law, Jessica Ka-Yan; Sam, Sze-Wing; Ingebrandt, Sven; Lau, Hang-Yung Alaster; Rudd, John Anthony; Chan, Mansun

    2008-06-01

    We performed this study to demonstrate the applicability of the microelectrode array (MEA) to study electrophysiological changes of rat peritoneal mast cells in the presence of compound 48/80 under normal, Ca(2+)-free, Ca(2+)-free with EDTA, and Cl(-)-free conditions. The use of high extracellular K(+) (KCl, 150 mM), charybdotoxin (ChTX, 100 nM), and Cl(-)-free containing ChTX buffers verified that the hyperpolarizing signal was due to the activation of mainly K(+) and, to a lesser extent, Cl(-) channels. Compound 48/80 concentration-dependently shortened the latent periods (the onset of response) and increased both the spatial (the K(+) and Cl(-) hyperpolarizing field potentials, HFP) and temporal measurements (the duration of response). Ca(2+)-free buffer had no effect on the latent period of compound 48/80 but increased the HFP at high concentrations. The latent period increased while the HFP diminished when cells were equilibrated in Ca(2+)-free buffer containing EDTA. Durations of the HFP were generally longer when cells were in either Ca(2+)-free or Ca(2+)-free containing EDTA buffers than when cells were in normal buffer. The EC(50) values confirmed that effects were only affected in Ca(2+)-free buffer containing EDTA but not in Ca(2+)-free or Cl(-)-free buffers, further reinforcing the hypothesis that the presence of Ca(2+) is not essential to the action of compound 48/80. The present study is the first application of MEA to study rat peritoneal mast cells, and our results indicate that it could be of value in future pharmacological research on other non-excitable cells.

  13. Fate of gamma-interferon-activated killer blood monocytes adoptively transferred into the abdominal cavity of patients with peritoneal carcinomatosis

    SciTech Connect

    Stevenson, H.C.; Keenan, A.M.; Woodhouse, C.; Ottow, R.T.; Miller, P.; Steller, E.P.; Foon, K.A.; Abrams, P.G.; Beman, J.; Larson, S.M.

    1987-11-15

    Five patients with colorectal cancer widely metastatic to peritoneal surfaces have been treated i.p. with infusions of autologous blood monocytes made cytotoxic by in vitro incubation with human gamma-interferon. The monocytes were purified by a combination of cytapheresis and counter-current centrifugal elutriation procedures; each week approximately 350 million activated monocytes were given to patients as adoptive immunotherapy by a single i.p. instillation. On the eighth cycle of treatment the trafficking of i.p. infused blood monocytes was studied in two patients by prelabeling the cells with /sup 111/In. These activated cells became distributed widely within the peritoneal cavity. Two and 5 days after infusion their position within the peritoneum had not changed. When peritoneal specimens were obtained 36 h after /sup 111/In-labeled monocyte infusion, labeled monocytes were demonstrated to be associated with the serosal surfaces by autoradiographic analysis. Scintiscanning structures outside the abdominal cavity revealed that /sup 111/In-labeled monocytes infused i.p. did not traffic to other organs during the 5 days of the study. We conclude that i.p. adoptive transfer of autologous killer blood monocytes is an effective way of delivering these cytotoxic cells to sites of tumor burden on peritoneal surfaces in these cancer patients.

  14. CCR2 deficiency leads to increased eosinophils, alternative macrophage activation, and type 2 cytokine expression in adipose tissue.

    PubMed

    Bolus, W Reid; Gutierrez, Dario A; Kennedy, Arion J; Anderson-Baucum, Emily K; Hasty, Alyssa H

    2015-10-01

    Adipose tissue (AT) inflammation during obesity is mediated by immune cells and closely correlates with systemic insulin resistance. In lean AT, eosinophils are present in low but significant numbers and capable of promoting alternative macrophage activation in an IL-4/IL-13-dependent manner. In WT mice, obesity causes the proportion of AT eosinophils to decline, concomitant with inflammation and classical activation of AT macrophages. In this study, we show that CCR2 deficiency leads to increased eosinophil accumulation in AT. Furthermore, in contrast to WT mice, the increase in eosinophils in CCR2(-/-) AT is sustained and even amplified during obesity. Interestingly, a significant portion of eosinophils is found in CLSs in AT of obese CCR2(-/-) mice, which is the first time eosinophils have been shown to localize to these inflammatory hot spots. CCR2(-/-) bone marrow precursors displayed increased expression of various key eosinophil genes during in vitro differentiation to eosinophils, suggesting a potentially altered eosinophil phenotype in the absence of CCR2. In addition, the proportion of eosinophils in AT positively correlated with local expression of Il5, a potent eosinophil stimulator. The increase in eosinophils in CCR2(-/-) mice was detected in all white fat pads analyzed and in the peritoneal cavity but not in bone marrow, blood, spleen, or liver. In AT of CCR2(-/-) mice, an increased eosinophil number positively correlated with M2-like macrophages, expression of the Treg marker Foxp3, and type 2 cytokines, Il4, Il5, and Il13. This is the first study to link CCR2 function with regulation of AT eosinophil accumulation.

  15. Macrophages sense and kill bacteria through carbon monoxide-dependent inflammasome activation.

    PubMed

    Wegiel, Barbara; Larsen, Rasmus; Gallo, David; Chin, Beek Yoke; Harris, Clair; Mannam, Praveen; Kaczmarek, Elzbieta; Lee, Patty J; Zuckerbraun, Brian S; Flavell, Richard; Soares, Miguel P; Otterbein, Leo E

    2014-11-01

    Microbial clearance by eukaryotes relies on complex and coordinated processes that remain poorly understood. The gasotransmitter carbon monoxide (CO) is generated by the stress-responsive enzyme heme oxygenase-1 (HO-1, encoded by Hmox1), which is highly induced in macrophages in response to bacterial infection. HO-1 deficiency results in inadequate pathogen clearance, exaggerated tissue damage, and increased mortality. Here, we determined that macrophage-generated CO promotes ATP production and release by bacteria, which then activates the Nacht, LRR, and PYD domains-containing protein 3 (NALP3) inflammasome, intensifying bacterial killing. Bacterial killing defects in HO-1-deficient murine macrophages were restored by administration of CO. Moreover, increased CO levels enhanced the bacterial clearance capacity of human macrophages and WT murine macrophages. CO-dependent bacterial clearance required the NALP3 inflammasome, as CO did not increase bacterial killing in macrophages isolated from NALP3-deficient or caspase-1-deficient mice. IL-1β cleavage and secretion were impaired in HO-1-deficient macrophages, and CO-dependent processing of IL-1β required the presence of bacteria-derived ATP. We found that bacteria remained viable to generate and release ATP in response to CO. The ATP then bound to macrophage nucleotide P2 receptors, resulting in activation of the NALP3/IL-1β inflammasome to amplify bacterial phagocytosis by macrophages. Taken together, our results indicate that macrophage-derived CO permits efficient and coordinated regulation of the host innate response to invading microbes.

  16. Interleukin-25 fails to activate STAT6 and induce alternatively activated macrophages.

    PubMed

    Stolfi, Carmine; Caruso, Roberta; Franzè, Eleonora; Sarra, Massimiliano; De Nitto, Daniela; Rizzo, Angelamaria; Pallone, Francesco; Monteleone, Giovanni

    2011-01-01

    Interleukin-25 (IL-25), a T helper type 2 (Th2) -related factor, inhibits the production of inflammatory cytokines by monocytes/macrophages. Since Th2 cytokines antagonize classically activated monocytes/macrophages by inducing alternatively activated macrophages (AAMs), we here assessed the effect of IL-25 on the alternative activation of human monocytes/macrophages. The interleukins IL-25, IL-4 and IL-13 were effective in reducing the expression of inflammatory chemokines in monocytes. This effect was paralleled by induction of AAMs in cultures added with IL-4 or IL-13 but not with IL-25, regardless of whether cells were stimulated with lipopolysaccharide or interferon-γ. Moreover, pre-incubation of cells with IL-25 did not alter the ability of both IL-4 and IL-13 to induce AAMs. Both IL-4 and IL-13 activated signal transducer and activator of transcription 6 (STAT6), and silencing of this transcription factor markedly reduced the IL-4/IL-13-driven induction of AAMs. In contrast, IL-25 failed to trigger STAT6 activation. Among Th2 cytokines, only IL-25 and IL-10 were able to activate p38 mitogen-activated protein kinase. These results collectively indicate that IL-25 fails to induce AAMs and that Th2-type cytokines suppress inflammatory responses in human monocytes by activating different intracellular signalling pathways.

  17. Impaired macrophage autophagy increases the immune response in obese mice by promoting proinflammatory macrophage polarization

    PubMed Central

    Liu, Kun; Zhao, Enpeng; Ilyas, Ghulam; Lalazar, Gadi; Lin, Yu; Haseeb, Muhammad; Tanaka, Kathryn E; Czaja, Mark J

    2015-01-01

    Recent evidence that excessive lipid accumulation can decrease cellular levels of autophagy and that autophagy regulates immune responsiveness suggested that impaired macrophage autophagy may promote the increased innate immune activation that underlies obesity. Primary bone marrow-derived macrophages (BMDM) and peritoneal macrophages from high-fat diet (HFD)-fed mice had decreased levels of autophagic flux indicating a generalized impairment of macrophage autophagy in obese mice. To assess the effects of decreased macrophage autophagy on inflammation, mice with a Lyz2-Cre-mediated knockout of Atg5 in macrophages were fed a HFD and treated with low-dose lipopolysaccharide (LPS). Knockout mice developed systemic and hepatic inflammation with HFD feeding and LPS. This effect was liver specific as knockout mice did not have increased adipose tissue inflammation. The mechanism by which the loss of autophagy promoted inflammation was through the regulation of macrophage polarization. BMDM and Kupffer cells from knockout mice exhibited abnormalities in polarization with both increased proinflammatory M1 and decreased anti-inflammatory M2 polarization as determined by measures of genes and proteins. The heightened hepatic inflammatory response in HFD-fed, LPS-treated knockout mice led to liver injury without affecting steatosis. These findings demonstrate that autophagy has a critical regulatory function in macrophage polarization that downregulates inflammation. Defects in macrophage autophagy may underlie inflammatory disease states such as the decrease in macrophage autophagy with obesity that leads to hepatic inflammation and the progression to liver injury. PMID:25650776

  18. Impaired macrophage autophagy increases the immune response in obese mice by promoting proinflammatory macrophage polarization.

    PubMed

    Liu, Kun; Zhao, Enpeng; Ilyas, Ghulam; Lalazar, Gadi; Lin, Yu; Haseeb, Muhammad; Tanaka, Kathryn E; Czaja, Mark J

    2015-01-01

    Recent evidence that excessive lipid accumulation can decrease cellular levels of autophagy and that autophagy regulates immune responsiveness suggested that impaired macrophage autophagy may promote the increased innate immune activation that underlies obesity. Primary bone marrow-derived macrophages (BMDM) and peritoneal macrophages from high-fat diet (HFD)-fed mice had decreased levels of autophagic flux indicating a generalized impairment of macrophage autophagy in obese mice. To assess the effects of decreased macrophage autophagy on inflammation, mice with a Lyz2-Cre-mediated knockout of Atg5 in macrophages were fed a HFD and treated with low-dose lipopolysaccharide (LPS). Knockout mice developed systemic and hepatic inflammation with HFD feeding and LPS. This effect was liver specific as knockout mice did not have increased adipose tissue inflammation. The mechanism by which the loss of autophagy promoted inflammation was through the regulation of macrophage polarization. BMDM and Kupffer cells from knockout mice exhibited abnormalities in polarization with both increased proinflammatory M1 and decreased anti-inflammatory M2 polarization as determined by measures of genes and proteins. The heightened hepatic inflammatory response in HFD-fed, LPS-treated knockout mice led to liver injury without affecting steatosis. These findings demonstrate that autophagy has a critical regulatory function in macrophage polarization that downregulates inflammation. Defects in macrophage autophagy may underlie inflammatory disease states such as the decrease in macrophage autophagy with obesity that leads to hepatic inflammation and the progression to liver injury.

  19. Microbiological aspects of peritonitis associated with continuous ambulatory peritoneal dialysis.

    PubMed Central

    von Graevenitz, A; Amsterdam, D

    1992-01-01

    The process of continuous ambulatory peritoneal dialysis has provided a useful, relatively inexpensive, and safe alternative for patients with end-stage renal disease. Infectious peritonitis, however, has limited a more widespread acceptance of this technique. The definition of peritonitis in this patient population is not universally accepted and does not always include the laboratory support of a positive culture (or Gram stain). In part, the omission of clinical microbiological findings stems from the lack of sensitivity of earlier microbiological efforts. Peritonitis results from decreased host phagocytic efficiency with depressed phagocytosis and bactericidal capacity of peritoneal macrophages. During episodes of peritonitis, fluid movement is reversed, away from the lymphatics and peritoneal membrane and toward the cavity. As a result, bloodstream infections are rare. Most peritonitis episodes are caused by bacteria. Coagulase-negative staphylococci are the most frequently isolated organisms, usually originating from the skin flora, but a wide array of microbial species have been documented as agents of peritonitis. Clinical microbiology laboratories need to be cognizant of the diverse agents so that appropriate primary media can be used. The quantity of dialysate fluid that is prepared for culture is critical and should constitute at least 10 ml. The sensitivity of the cultural approach depends on the volume of dialysate, its pretreatment (lysis or centrifugation), the media used, and the mode of incubation. The low concentration of microorganisms in dialysate fluids accounts for negative Gram stain results. Prevention of infection in continuous ambulatory peritoneal dialysis patients is associated with the socioeconomic status of the patient, advances in equipment (catheter) technology, and, probably least important, the application of prophylactic antimicrobial agents. PMID:1735094

  20. Inhibitory effect of vitamin D-binding protein-derived macrophage activating factor on DMBA-induced hamster cheek pouch carcinogenesis and its derived carcinoma cell line

    PubMed Central

    TOYOHARA, YUKIYO; HASHITANI, SUSUMU; KISHIMOTO, HIROMITSU; NOGUCHI, KAZUMA; YAMAMOTO, NOBUTO; URADE, MASAHIRO

    2011-01-01

    This study investigated the inhibitory effect of vitamin D-binding protein-derived macrophage-activating factor (GcMAF) on carcinogenesis and tumor growth, using a 9,10-dimethyl-1,2-benzanthracene (DMBA)-induced hamster cheek pouch carcinogenesis model, as well as the cytocidal effect of activated macrophages against HCPC-1, a cell line established from DMBA-induced cheek pouch carcinoma. DMBA application induced squamous cell carcinoma in all 15 hamsters of the control group at approximately 10 weeks, and all 15 hamsters died of tumor burden within 20 weeks. By contrast, 2 out of the 14 hamsters with GcMAF administration did not develop tumors and the remaining 12 hamsters showed a significant delay of tumor development for approximately 3.5 weeks. The growth of tumors formed was significantly suppressed and none of the hamsters died within the 20 weeks during which they were observed. When GcMAF administration was stopped at the 13th week of the experiment in 4 out of the 14 hamsters in the GcMAF-treated group, tumor growth was promoted, but none of the mice died within the 20-week period. On the other hand, when GcMAF administration was commenced after the 13th week in 5 out of the 15 hamsters in the control group, tumor growth was slightly suppressed and all 15 hamsters died of tumor burden. However, the mean survival time was significantly extended. GcMAF treatment activated peritoneal macrophages in vitro and in vivo, and these activated macrophages exhibited a marked cytocidal effect on HCPC-1 cells. Furthermore, the cytocidal effect of activated macrophages was enhanced by the addition of tumor-bearing hamster serum. These findings indicated that GcMAF possesses an inhibitory effect on tumor development and growth in a DMBA-induced hamster cheek pouch carcinogenesis model. PMID:22848250

  1. Inhibitory effect of vitamin D-binding protein-derived macrophage activating factor on DMBA-induced hamster cheek pouch carcinogenesis and its derived carcinoma cell line.

    PubMed

    Toyohara, Yukiyo; Hashitani, Susumu; Kishimoto, Hiromitsu; Noguchi, Kazuma; Yamamoto, Nobuto; Urade, Masahiro

    2011-07-01

    This study investigated the inhibitory effect of vitamin D-binding protein-derived macrophage-activating factor (GcMAF) on carcinogenesis and tumor growth, using a 9,10-dimethyl-1,2-benzanthracene (DMBA)-induced hamster cheek pouch carcinogenesis model, as well as the cytocidal effect of activated macrophages against HCPC-1, a cell line established from DMBA-induced cheek pouch carcinoma. DMBA application induced squamous cell carcinoma in all 15 hamsters of the control group at approximately 10 weeks, and all 15 hamsters died of tumor burden within 20 weeks. By contrast, 2 out of the 14 hamsters with GcMAF administration did not develop tumors and the remaining 12 hamsters showed a significant delay of tumor development for approximately 3.5 weeks. The growth of tumors formed was significantly suppressed and none of the hamsters died within the 20 weeks during which they were observed. When GcMAF administration was stopped at the 13th week of the experiment in 4 out of the 14 hamsters in the GcMAF-treated group, tumor growth was promoted, but none of the mice died within the 20-week period. On the other hand, when GcMAF administration was commenced after the 13th week in 5 out of the 15 hamsters in the control group, tumor growth was slightly suppressed and all 15 hamsters died of tumor burden. However, the mean survival time was significantly extended. GcMAF treatment activated peritoneal macrophages in vitro and in vivo, and these activated macrophages exhibited a marked cytocidal effect on HCPC-1 cells. Furthermore, the cytocidal effect of activated macrophages was enhanced by the addition of tumor-bearing hamster serum. These findings indicated that GcMAF possesses an inhibitory effect on tumor development and growth in a DMBA-induced hamster cheek pouch carcinogenesis model.

  2. Alteration of some cellular function in amikacin resistant Pseudomonas aeruginosa transfected macrophages: a time dependent approach

    PubMed Central

    Chakraborty, Subhankari Prasad; KarMahapatra, Santanu; Das, Sabyasachi; Roy, Somenath

    2011-01-01

    Objective To evaluate the free radical generation and antioxidant enzymes status in murine peritoneal macrophage during in vitro amikacin resistant Pseudomonas aeruginosa (ARPA) treatment with different time interval. Methods Peritoneal macrophages were treated with 1×108 CFU/mL ARPA cell suspension in vitro for different time interval (1, 2, 3, 6, 12, and 24 h) and super oxide anion generation, NO generation, reduced glutathione level and antioxidant enzymes status were analyzed. Results Super oxide anion generation and NO generation got peak at 12 h, indicating maximal free radical generation through activation of NADPH oxidase in murine peritoneal macrophages during ARPA transfection. Reduced glutathione level and antioxidant enzymes status were decreased significantly (P<0.05) with increasing time of ARPA transfection. All the changes in peritoneal macrophages after 12 h in vitro ARPA transfection had significant difference (P<0.05). Conclusions From this study, it may be summarized that in vitro ARPA infection not only generates excess free radical but also affects the antioxidant system and glutathione cycle in murine peritoneal macrophage. PMID:23569818

  3. CKIP-1 regulates macrophage proliferation by inhibiting TRAF6-mediated Akt activation

    PubMed Central

    Zhang, Luo; Wang, Yiwu; Xiao, Fengjun; Wang, Shaoxia; Xing, Guichun; Li, Yang; Yin, Xiushan; Lu, Kefeng; Wei, Rongfei; Fan, Jiao; Chen, Yuhan; Li, Tao; Xie, Ping; Yuan, Lin; Song, Lei; Ma, Lanzhi; Ding, Lujing; He, Fuchu; Zhang, Lingqiang

    2014-01-01

    Macrophages play pivotal roles in development, homeostasis, tissue repair and immunity. Macrophage proliferation is promoted by macrophage colony-stimulating factor (M-CSF)-induced Akt signaling; yet, how this process is terminated remains unclear. Here, we identify casein kinase 2-interacting protein-1 (CKIP-1) as a novel inhibitor of macrophage proliferation. In resting macrophages, CKIP-1 was phosphorylated at Serine 342 by constitutively active GSK3β, the downstream target of Akt. This phosphorylation triggers the polyubiquitination and proteasomal degradation of CKIP-1. Upon M-CSF stimulation, Akt is activated by CSF-1R-PI3K and then inactivates GSK3β, leading to the stabilization of CKIP-1 and β-catenin proteins. β-catenin promotes the expression of proliferation genes including cyclin D and c-Myc. CKIP-1 interacts with TRAF6, a ubiquitin ligase required for K63-linked ubiquitination and plasma membrane recruitment of Akt, and terminates TRAF6-mediated Akt activation. By this means, CKIP-1 inhibits macrophage proliferation specifically at the late stage after M-CSF stimulation. Furthermore, CKIP-1 deficiency results in increased proliferation and decreased apoptosis of macrophages in vitro and CKIP-1−/− mice spontaneously develop a macrophage-dominated splenomegaly and myeloproliferation. Together, these data demonstrate that CKIP-1 plays a critical role in the regulation of macrophage homeostasis by inhibiting TRAF6-mediated Akt activation. PMID:24777252

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

    SciTech Connect

    Mayi, Therese Hervee; Rigamonti, Elena; Pattou, Francois; Staels, Bart; Chinetti-Gbaguidi, Giulia

    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.

  5. Macrophage activation syndrome in the era of biologic therapy.

    PubMed

    Grom, Alexei A; Horne, AnnaCarin; De Benedetti, Fabrizio

    2016-05-01

    Macrophage activation syndrome (MAS) refers to acute overwhelming inflammation caused by a 'cytokine storm'. Although increasingly recognized as a life-threatening complication of various rheumatic diseases, clinically, MAS is strikingly similar to primary and secondary forms of haemophagocytic lymphohistiocytosis (HLH). Not surprisingly, many rheumatologists prefer the term secondary HLH rather than MAS to describe this condition, and efforts to change the nomenclature are in progress. The pathophysiology of MAS remains elusive, but observations in animal models, as well as data on the effects of new anticytokine therapies on rates and clinical presentations of MAS in patients with systemic juvenile idiopathic arthritis (sJIA), provide clues to the understanding of this perplexing clinical phenomenon. In this Review, we explore the latest available evidence and discuss potential diagnostic challenges in the era of increasing use of biologic therapies.

  6. [Impact of abdominal cavity open EHF irradiation on activity of adhesive process in peritonitis].

    PubMed

    Boĭko, V V; Ivanova, Iu V; Gamidov, A N; Andreeshchev, S A

    2015-01-01

    In experiment on 45 rats a purulent peritonitis was simulated. There was established, that on background of a standard therapy for peritonitis application of abdominal cavity open irradiation of extreme high frequency (EHF) have promoted rapid stabilization of the lipid metabolism indices and the blood coagulation system, the reduction of intensity of lipids peroxidal oxidation processes and severity of systemic inflammatory reaction. Under the influence of complex treatment the severity of adhesive process was reduced in 5.4 times, comparing with such in animals, to whom a standard treatment was conducted only. The revealed pathogenetic aspects of the adhesions formation witnesses the expediency to add EHF irradiation to complex therapy of peritonitis.

  7. Chronic hepatitis C infection–induced liver fibrogenesis is associated with M2 macrophage activation

    PubMed Central

    Bility, Moses T.; Nio, Kouki; Li, Feng; McGivern, David R.; Lemon, Stanley M.; Feeney, Eoin R.; Chung, Raymond T.; Su, Lishan

    2016-01-01

    The immuno-pathogenic mechanisms of chronic hepatitis C virus (HCV) infection remain to be elucidated and pose a major hurdle in treating or preventing chronic HCV-induced advanced liver diseases such as cirrhosis. Macrophages are a major component of the inflammatory milieu in chronic HCV–induced liver disease, and are generally derived from circulating inflammatory monocytes; however very little is known about their role in liver diseases. To investigate the activation and role of macrophages in chronic HCV–induced liver fibrosis, we utilized a recently developed humanized mouse model with autologous human immune and liver cells, human liver and blood samples and cell culture models of monocyte/macrophage and/or hepatic stellate cell activation. We showed that M2 macrophage activation was associated with liver fibrosis during chronic HCV infection in the livers of both humanized mice and patients, and direct-acting antiviral therapy attenuated M2 macrophage activation and associated liver fibrosis. We demonstrated that supernatant from HCV-infected liver cells activated human monocytes/macrophages with M2-like phenotypes. Importantly, HCV-activated monocytes/macrophages promoted hepatic stellate cell activation. These results suggest a critical role for M2 macrophage induction in chronic HCV-associated immune dysregulation and liver fibrosis. PMID:28000758

  8. Chronic hepatitis C infection-induced liver fibrogenesis is associated with M2 macrophage activation.

    PubMed

    Bility, Moses T; Nio, Kouki; Li, Feng; McGivern, David R; Lemon, Stanley M; Feeney, Eoin R; Chung, Raymond T; Su, Lishan

    2016-12-21

    The immuno-pathogenic mechanisms of chronic hepatitis C virus (HCV) infection remain to be elucidated and pose a major hurdle in treating or preventing chronic HCV-induced advanced liver diseases such as cirrhosis. Macrophages are a major component of the inflammatory milieu in chronic HCV-induced liver disease, and are generally derived from circulating inflammatory monocytes; however very little is known about their role in liver diseases. To investigate the activation and role of macrophages in chronic HCV-induced liver fibrosis, we utilized a recently developed humanized mouse model with autologous human immune and liver cells, human liver and blood samples and cell culture models of monocyte/macrophage and/or hepatic stellate cell activation. We showed that M2 macrophage activation was associated with liver fibrosis during chronic HCV infection in the livers of both humanized mice and patients, and direct-acting antiviral therapy attenuated M2 macrophage activation and associated liver fibrosis. We demonstrated that supernatant from HCV-infected liver cells activated human monocytes/macrophages with M2-like phenotypes. Importantly, HCV-activated monocytes/macrophages promoted hepatic stellate cell activation. These results suggest a critical role for M2 macrophage induction in chronic HCV-associated immune dysregulation and liver fibrosis.

  9. Macrophage activity and histopathology of the lymphohematopoietic organs in male Wistar rats orally exposed to single or mixed pesticides.

    PubMed

    De Camargo, Marcela Rodrigues; Barbisan, Luís Fernando; Martinez, Meire França; Da Silva Franchi, Carla Adriene; De Camargo, João Lauro Viana; Spinardi-Barbisan, Ana Lúcia Tozzi

    2013-01-01

    The noxious effects of low or effective dose exposure to single or mixed pesticides on macrophage activity and the lymphohematopoietic organs were investigated. Male Wistar rats were orally exposed to dichlorvos, dicofol, endosulfan, dieldrin and permethrin, either as single or combined mixtures during a 28-day study containing eight groups: one group received a semipurified diet (non-treated); two groups received a semipurified diet containing low dose mixture (dieldrin 0.025 mg/kg, endosulfan, 0.6 mg/kg, dicofol 0.22 mg/kg, dichlorvos 0.23 mg/kg, permethrin 5 mg/kg) or an effective dose mixture (dichlorvos 2.3 mg/kg, dicofol 2.5 mg/kg, endosulfan 2.9 mg/kg, dieldrin 0.05 mg/kg and permethrin 25.0 mg/kg), respectively; the other five groups received a semipurified diet containing each single pesticide in effective doses. At sacrifice, the thymus, spleen, mesenteric lymph nodes, Payer's patches and bone marrow were removed for histological analysis. Peritoneal macrophages were obtained to determine the phagocytosis and spreading indexes and tumoral necrosis factor alpha (TNF-α), nitric oxide (NO) and H₂O₂ production. Exposure to pesticide mixtures did not alter the percentage of macrophage phagocytosis and spreading, TNF-α production or the NO and H₂O₂ release when compared to the non-treated group. Neither was there any apparent evidence that a pesticide mixture at low or effective doses altered the histological structure of the lymphohematopoietic organs. The findings indicate that short-term treatment with pesticide mixtures did not induce an apparent immunotoxic effect in male Wistar rats.

  10. Arctigenin ameliorates inflammation in vitro and in vivo by inhibiting the PI3K/AKT pathway and polarizing M1 macrophages to M2-like macrophages.

    PubMed

    Hyam, Supriya R; Lee, In-Ah; Gu, Wan; Kim, Kyung-Ah; Jeong, Jin-Ju; Jang, Se-Eun; Han, Myung Joo; Kim, Dong-Hyun

    2013-05-15

    Seeds of Arctium lappa, containing arctigenin and its glycoside arctiin as main constituents, have been used as a diuretic, anti-inflammatory and detoxifying agent in Chinese traditional medicine. In our preliminary study, arctigenin inhibited IKKβ and NF-κB activation in peptidoglycan (PGN)- or lipopolysaccharide (LPS)-induced peritoneal macrophages. To understand the anti-inflammatory effect of arctigenin, we investigated its anti-inflammatory effect in LPS-stimulated peritoneal macrophages and on LPS-induced systemic inflammation as well as 2,4,6-trinitrobenzene sulfonic acid (TNBS)-induced colitis in mice. Arctigenin inhibited LPS-increased IL-1β, IL-6 and TNF-α expression in LPS-stimulated peritoneal macrophages, but increased LPS-reduced IL-10 and CD204 expression. Arctigenin inhibited LPS-induced PI3K, AKT and IKKβ phosphorylation, but did not suppress LPS-induced IRAK-1 phosphorylation. However, arctigenin did not inhibit NF-κB activation in LPS-stimulated PI3K siRNA-treated peritoneal macrophages. Arctigenin suppressed the binding of p-PI3K antibody and the nucleus translocation of NF-κB p65 in LPS-stimulated peritoneal macrophages. Arctigenin suppressed blood IL-1β and TNF-α level in mice systemically inflamed by intraperitoneal injection of LPS. Arctigenin also inhibited colon shortening, macroscopic scores and myeloperoxidase activity in TNBS-induced colitic mice. Arctigenin inhibited TNBS-induced IL-1β, TNF-α and IL-6 expression, as well as PI3K, AKT and IKKβ phosphorylation and NF-κB activation in mice, but increased IL-10 and CD204 expression. However, it did not affect IRAK-1 phosphorylation. Based on these findings, arctigenin may ameliorate inflammatory diseases, such as colitis, by inhibiting PI3K and polarizing M1 macrophages to M2-like macrophages.

  11. Roles of alternatively activated M2 macrophages in allergic contact dermatitis.

    PubMed

    Suzuki, Kotaro; Meguro, Kazuyuki; Nakagomi, Daiki; Nakajima, Hiroshi

    2017-03-17

    Alternatively activated macrophages (M2 macrophages) play key roles in the suppression of Th1 cell responses and the orchestration of tissue repair. However, recent studies have shown that M2 macrophages have potentials to produce high levels of proinflammatory cytokines such as IL-1β, IL-6, and TNF-α, suggesting that M2 macrophages may exacerbate inflammation in some settings. In this regard, we have recently shown that large numbers of M2 macrophages accumulate in the sites of hapten-induced contact hypersensitivity (CHS), an animal model of allergic contact dermatitis, and that M2 macrophages exacerbate hapten-induced CHS by producing matrix metalloproteinase 12 (MMP12). We have also shown that suppressor of cytokine signaling-3 (SOCS3), a member of SOCS family proteins that are cytokine-inducible negative regulators of the JAK/STAT signaling pathways, is highly and preferentially expressed in M2 macrophages in hapten-induced CHS and that SOCS3 expressed in M2 macrophages is involved in the attenuation of CHS by suppressing MMP12 production. These findings underscore the importance of M2 macrophage-derived MMP12 in the development of CHS, and suggest that inhibition of M2 macrophages or MMP12 could be a potential therapeutic strategy for the treatment of allergic contact dermatitis.

  12. Pyrazolopyrimidines: synthesis, effect on histamine release from rat peritoneal mast cells and cytotoxic activity.

    PubMed

    Quintela, J M; Peinador, C; Moreira, M J; Alfonso, A; Botana, L M; Riguera, R

    2001-04-01

    A series of 1H-pyrazolo[3,4-d]pyrimidines (3--6) substituted at positions 1 (R(1)=Ph, H, tert-butyl and ribosetribenzoate), 4 (R(2)=chlorine, nitrogen and oxygen nucleophiles), and 6 (dimethylamino) have been synthesized and their effect on the release of histamine from rat peritoneal mast cells measured. After chemical stimulation, (polymer 48/80), several compounds (i.e. 3b, 4a, 4b, 4d, 4g, 5a), produce inhibition two to three times higher (40--60%) than DSCG but this action is lower after preincubation. 4b (R(1)=Ph, R(2)=NHCH(2)Ph; 50--70% inhibition) and 5a (R(1)=H, R(2)=OMe; 50--55% inhibition) are the most active ones in both experiments. With ovoalbumin as stimulus, several pyrazolopyrimidines show inhibition similar to DSCG, the most active compounds being 6a--d (IC(50)=12--16 microM; R(1)=ribosetribenzoate, R(2)=methoxy and amino). Compounds 4e (R(1)=t-butyl, R(2)=OMe) and 4g (R(1)=t-butyl, R(2)=piperidino) are inducers of the release of histamine (60 and 150% increase). Compounds 4b and 4c showed cytotoxic activity (IC(50)=1 microg/mL) to HT-29 human colon cancer cells.

  13. Macrophage Infiltration and Alternative Activation during Wound Healing Promote MEK1-Induced Skin Carcinogenesis.

    PubMed

    Weber, Christine; Telerman, Stephanie B; Reimer, Andreas S; Sequeira, Ines; Liakath-Ali, Kifayathullah; Arwert, Esther N; Watt, Fiona M

    2016-02-15

    Macrophages are essential for the progression and maintenance of many cancers, but their role during the earliest stages of tumor formation is unclear. To test this, we used a previously described transgenic mouse model of wound-induced skin tumorigenesis, in which expression of constitutively active MEK1 in differentiating epidermal cells results in chronic inflammation (InvEE mice). Upon wounding, the number of epidermal and dermal monocytes and macrophages increased in wild-type and InvEE skin, but the increase was greater, more rapid, and more sustained in InvEE skin. Macrophage ablation reduced tumor incidence. Furthermore, bioluminescent imaging in live mice to monitor macrophage flux at wound sites revealed that macrophage accumulation was predictive of tumor formation; wounds with the greatest number of macrophages at day 5 went on to develop tumors. Gene expression profiling of flow-sorted monocytes, macrophages, and T cells from InvEE and wild-type skin showed that as wound healing progressed, InvEE macrophages altered their phenotype. Throughout wound healing and after wound closure, InvEE macrophages demonstrated sustained upregulation of several markers implicated in alternative macrophage activation including arginase-1 (ARG1) and mannose receptor (CD206). Notably, inhibition of ARG1 activity significantly reduced tumor formation and epidermal proliferation in vivo, whereas addition of L-arginase to cultured keratinocytes stimulated proliferation. We conclude that macrophages play a key role in early, inflammation-mediated skin tumorigenesis, with mechanistic evidence suggesting that ARG1 secretion drives tumor development by stimulating epidermal cell proliferation. These findings highlight the importance of cancer immunotherapies aiming to polarize tumor-associated macrophages toward an antitumor phenotype.

  14. Macrophage migration inhibitory factor (MIF) enzymatic activity and lung cancer.

    PubMed

    Mawhinney, Leona; Armstrong, Michelle E; O' Reilly, Ciaran; Bucala, Richard; Leng, Lin; Fingerle-Rowson, Gunter; Fayne, Darren; Keane, Michael P; Tynan, Aisling; Maher, Lewena; Cooke, Gordon; Lloyd, David; Conroy, Helen; Donnelly, Seamas C

    2015-04-16

    The cytokine macrophage migration inhibitory factor (MIF) possesses unique tautomerase enzymatic activity, which contributes to the biological functional activity of MIF. In this study, we investigated the effects of blocking the hydrophobic active site of the tautomerase activity of MIF in the pathogenesis of lung cancer. To address this, we initially established a Lewis lung carcinoma (LLC) murine model in Mif-KO and wild-type (WT) mice and compared tumor growth in a knock-in mouse model expressing a mutant MIF lacking enzymatic activity (Mif (P1G)). Primary tumor growth was significantly attenuated in both Mif-KO and Mif (P1G) mice compared with WT mice. We subsequently undertook a structure-based, virtual screen to identify putative small molecular weight inhibitors specific for the tautomerase enzymatic active site of MIF. From primary and secondary screens, the inhibitor SCD-19 was identified, which significantly attenuated the tautomerase enzymatic activity of MIF in vitro and in biological functional screens. In the LLC murine model, SCD-19, given intraperitoneally at the time of tumor inoculation, was found to significantly reduce primary tumor volume by 90% (p < 0.001) compared with the control treatment. To better replicate the human disease scenario, SCD-19 was given when the tumor was palpable (at d 7 after tumor inoculation) and, again, treatment was found to significantly reduce tumor volume by 81% (p < 0.001) compared with the control treatment. In this report, we identify a novel inhibitor that blocks the hydrophobic pocket of MIF, which houses its specific tautomerase enzymatic activity, and demonstrate that targeting this unique active site significantly attenuates lung cancer growth in in vitro and in vivo systems.

  15. Effects of endogenous antidiuretic hormone (ADH) on macrophage phagocytosis

    SciTech Connect

    Fernandez-Repollet, E.; Opava-Stitzer, S.; Tiffany, S.; Schwartz, A.

    1983-07-01

    Although several studies have indicated that antidiuretic hormone (ADH) enhances the phagocytic function of the reticuloendothelial system (RES) in shock syndromes, it remains unknown what influence ADH exerts upon the individual phagocytic components of this system. The present investigation was designed to evaluate the effects of endogenous ADH on the phagocytic activity of peritoneal macrophage cells. As a phagocytic stimuli, fluorescent methacrylate microbeads were injected intraperitoneally into Brattleboro (ADH deficient) and normal Long Evans rats in the presence and absence of exogenous ADH. Peritoneal cells were harvested 19-22 hr after the administration of the microbeads and the percent phagocytosis was determined in macrophage cells using a fluorescence-activated cell sorter (FACS II). Our results indicate that the percentage of peritoneal macrophages ingesting the fluorescent methacrylate microbeads was significantly reduced in the absence of ADH (Brattleboro rats: 5.4 +/- 0.6% versus Long Evans rats: 16.8 +/- 2.3%; p less than 0.001). In addition, our data demonstrate that exogenous administration of ADH significantly enhanced macrophage phagocytosis in Brattleboro (14.7 +/- 2.2%) and normal Long Evans (49.6 +/- 4.5%) rats. These data suggest, for the first time, that endogenous ADH might play a modulatory role in the phagocytic activity of a specific component of the RES, namely, the macrophage cell.

  16. Kinetics of tumor necrosis factor production by photodynamic-therapy-activated macrophages

    NASA Astrophysics Data System (ADS)

    Pass, Harvey I.; Evans, Steven; Perry, Roger; Matthews, Wilbert

    1990-07-01

    The ability of photodynamic therapy (PDT) to activate macrophages and produce cytokines, specifically tumor necrosis factor (TNF), is unknown. Three day thioglycolate elicited macrophages were incubated with 25 ug/mi Photofrin II (P11) for 2 hour, after which they were subjected to 630 nm light with fluences of 0-1800 J/m. The amount of TNF produced in the system as well as macrophage viability was measured 1, 3, 6, and 18 hours after POT. The level of TNF produced by the macrophages was significantly elevated over control levels 6 hours after POT and the absolute level of tumor necrosis factor production was influenced by the treatment energy and the resulting macrophage cytotoxicity. These data suggest that POT therapy induced cytotoxicity in vivo may be amplified by macrophage stimulation to secrete cytokines and these cytokines may also participate in other direct/indirect photodynamic therapy effects, i.e. immunosuppression, vascular effects.

  17. Macrophages Contribute to the Cyclic Activation of Adult Hair Follicle Stem Cells

    PubMed Central

    Castellana, Donatello; Paus, Ralf; Perez-Moreno, Mirna

    2014-01-01

    Skin epithelial stem cells operate within a complex signaling milieu that orchestrates their lifetime regenerative properties. The question of whether and how immune cells impact on these stem cells within their niche is not well understood. Here we show that skin-resident macrophages decrease in number because of apoptosis before the onset of epithelial hair follicle stem cell activation during the murine hair cycle. This process is linked to distinct gene expression, including Wnt transcription. Interestingly, by mimicking this event through the selective induction of macrophage apoptosis in early telogen, we identify a novel involvement of macrophages in stem cell activation in vivo. Importantly, the macrophage-specific pharmacological inhibition of Wnt production delays hair follicle growth. Thus, perifollicular macrophages contribute to the activation of skin epithelial stem cells as a novel, additional cue that regulates their regenerative activity. This finding may have translational implications for skin repair, inflammatory skin diseases and cancer. PMID:25536657

  18. Candida albicans Chitin Increases Arginase-1 Activity in Human Macrophages, with an Impact on Macrophage Antimicrobial Functions

    PubMed Central

    MacCallum, Donna M.; Brown, Gordon D.

    2017-01-01

    ABSTRACT   The opportunistic human fungal pathogen Candida albicans can cause a variety of diseases, ranging from superficial mucosal infections to life-threatening systemic infections. Phagocytic cells of the innate immune response, such as neutrophils and macrophages, are important first-line responders to an infection and generate reactive oxygen and nitrogen species as part of their protective antimicrobial response. During an infection, host cells generate nitric oxide through the enzyme inducible nitric oxide synthase (iNOS) to kill the invading pathogen. Inside the phagocyte, iNOS competes with the enzyme arginase-1 for a common substrate, the amino acid l-arginine. Several pathogenic species, including bacteria and parasitic protozoans, actively modulate the production of nitric oxide by inducing their own arginases or the host’s arginase activity to prevent the conversion of l-arginine to nitric oxide. We report here that C. albicans blocks nitric oxide production in human-monocyte-derived macrophages by induction of host arginase activity. We further determined that purified chitin (a fungal cell wall polysaccharide) and increased chitin exposure at the fungal cell wall surface induces this host arginase activity. Blocking the C. albicans-induced arginase activity with the arginase-specific substrate inhibitor Nω-hydroxy-nor-arginine (nor-NOHA) or the chitinase inhibitor bisdionin F restored nitric oxide production and increased the efficiency of fungal killing. Moreover, we determined that C. albicans influences macrophage polarization from a classically activated phenotype toward an alternatively activated phenotype, thereby reducing antimicrobial functions and mediating fungal survival. Therefore, C. albicans modulates l-arginine metabolism in macrophages during an infection, potentiating its own survival. PMID:28119468

  19. Hybrid-Actuating Macrophage-Based Microrobots for Active Cancer Therapy

    PubMed Central

    Han, Jiwon; Zhen, Jin; Du Nguyen, Van; Go, Gwangjun; Choi, Youngjin; Ko, Seong Young; Park, Jong-Oh; Park, Sukho

    2016-01-01

    Using macrophage recruitment in tumors, we develop active, transportable, cancer theragnostic macrophage-based microrobots as vector to deliver therapeutic agents to tumor regions. The macrophage-based microrobots contain docetaxel (DTX)-loaded poly-lactic-co-glycolic-acid (PLGA) nanoparticles (NPs) for chemotherapy and Fe3O4 magnetic NPs (MNPs) for active targeting using an electromagnetic actuation (EMA) system. And, the macrophage-based microrobots are synthesized through the phagocytosis of the drug NPs and MNPs in the macrophages. The anticancer effects of the microrobots on tumor cell lines (CT-26 and 4T1) are evaluated in vitro by cytotoxic assay. In addition, the active tumor targeting by the EMA system and macrophage recruitment, and the chemotherapeutic effect of the microrobots are evaluated using three-dimensional (3D) tumor spheroids. The microrobots exhibited clear cytotoxicity toward tumor cells, with a low survivability rate (<50%). The 3D tumor spheroid assay showed that the microrobots demonstrated hybrid actuation through active tumor targeting by the EMA system and infiltration into the tumor spheroid by macrophage recruitment, resulting in tumor cell death caused by the delivered antitumor drug. Thus, the active, transportable, macrophage-based theragnostic microrobots can be considered to be biocompatible vectors for cancer therapy. PMID:27346486

  20. Adipogenic role of alternatively activated macrophages in β-adrenergic remodeling of white adipose tissue.

    PubMed

    Lee, Yun-Hee; Kim, Sang-Nam; Kwon, Hyun-Jung; Maddipati, Krishna Rao; Granneman, James G

    2016-01-01

    De novo brown adipogenesis involves the proliferation and differentiation of progenitors, yet the mechanisms that guide these events in vivo are poorly understood. We previously demonstrated that treatment with a β3-adrenergic receptor (ADRB3) agonist triggers brown/beige adipogenesis in gonadal white adipose tissue following adipocyte death and clearance by tissue macrophages. The close physical relationship between adipocyte progenitors and tissue macrophages suggested that the macrophages that clear dying adipocytes might generate proadipogenic factors. Flow cytometric analysis of macrophages from mice treated with CL 316,243 identified a subpopulation that contained elevated lipid and expressed CD44. Lipidomic analysis of fluorescence-activated cell sorting-isolated macrophages demonstrated that CD44+ macrophages contained four- to five-fold higher levels of the endogenous peroxisome-proliferator activated receptor gamma (PPARγ) ligands 9-hydroxyoctadecadienoic acid (HODE), and 13-HODE compared with CD44- macrophages. Gene expression profiling and immunohistochemistry demonstrated that ADRB3 agonist treatment upregulated expression of ALOX15, the lipoxygenase responsible for generating 9-HODE and 13-HODE. Using an in vitro model of adipocyte efferocytosis, we found that IL-4-primed tissue macrophages accumulated lipid from dying fat cells and upregulated expression of Alox15. Furthermore, treatment of differentiating adipocytes with 9-HODE and 13-HODE potentiated brown/beige adipogenesis. Collectively, these data indicate that noninflammatory removal of adipocyte remnants and coordinated generation of PPARγ ligands by M2 macrophages provides localized adipogenic signals to support de novo brown/beige adipogenesis.

  1. Alternative activation and increase of Trypanosoma cruzi survival in murine macrophages stimulated by cruzipain, a parasite antigen.

    PubMed

    Stempin, Cinthia; Giordanengo, Laura; Gea, Susana; Cerbán, Fabio

    2002-10-01

    We studied the macrophage (Mo) activation pathways through Mo interaction with immunogenic Trypanosoma cruzi antigens as cruzipain (Cz) and R13. J774 cells, peritoneal and spleen Mo from normal mice, were used. Although Mo classic activation was observed in the presence of lipopolysaccharide, evaluated through nitric oxide (NO) and interleukin (IL)-12 production, Cz and R13 did not activate Mo in this way. To study the alternative pathway, we examined the arginase activity in Mo cultured with Cz. An increase of arginase activity was detected in all Mo sources assayed. An increase of IL-10 and transforming growth factor-beta in culture supernatants from Mo stimulated with Cz was observed. The study of expression of B7.1 and B7.2 in spleen Mo revealed that Cz induces preferential expression of B7.2. In vitro studies revealed that Cz stimulated J774 cells and then, infected with trypomastigotes of T. cruzi, developed a higher number of intracellular parasites than unstimulated infected Mo. Thus, Cz favors the perpetuation of T. cruzi infection. In addition, a down-regulation of inducible NO synthase was observed in J774 cells stimulated with Cz. These results suggest that Cz interaction with Mo could modulate the immune response generated against T. cruzi through the induction of a preferential metabolic pathway in Mo.

  2. Genetic Control of the Innate Resistance of Mice to Salmonella typhimurium: Expression of the Ity Gene in Peritoneal Macrophages Isolated In Vitro

    DTIC Science & Technology

    1984-07-20

    Statistical Analysis 67 RESULTS Configuration of the _In Vitro Salmonella Infection Assay 68 I. Assessment of the cellular composition of resident... Salmonella Infection Assay I. Assessment of the cellular composition of resident adherent macrophages at the time of infection The methods used for...point of Salmonella infection . At that time, the macrophage cultures were overlaid with 500 pi/well of the lidocaine solution, and incubated at 37° C

  3. Membrane-Tethered MUC1 Mucin Counter-Regulates the Phagocytic Activity of Macrophages.

    PubMed

    Kato, Kosuke; Uchino, Reina; Lillehoj, Erik P; Knox, Kenneth; Lin, Yong; Kim, K Chul

    2016-04-01

    MUC1 (MUC in human; Muc in animals) is a transmembrane mucin glycoprotein expressed in mucosal epithelial cells and hematopoietic cells. MUC1 is involved in the resolution of inflammation during airway Pseudomonas aeruginosa (Pa) infection by suppressing Toll-like receptor signaling in airway epithelial cells. Although alveolar macrophages are recognized as critical mediators of cell-mediated immunity against microorganisms inhaled into the airways, the role of MUC1 in regulating their response is unknown. The aims of this study were to determine whether macrophages express MUC1, and, if so, whether MUC1 expression might be associated with macrophage M0/M1/M2 differentiation or phagocytic activity. Human and mouse MUC1/Muc1 expression was drastically up-regulated in classically activated (M1) macrophages compared with nonactivated (M0) and alternatively activated (M2) macrophages. M1 polarization and Pa stimulation each increased MUC1 ectodomain shedding from the macrophage surface in a TNF-α-converting enzyme-dependent manner. MUC1/Muc1 deficiency in M0 macrophages increased adhesion and phagocytosis of Pa and Escherichia coli compared with MUC1/Muc1-expressing cells, and attenuation of phagocytosis by MUC1 was augmented after polarization into M1 macrophages compared with M0 macrophages. Finally, MUC1/Muc1 deficiency in macrophages increased reactive oxygen species production and TNF-α release in response to Pa compared with MUC1/Muc1-sufficient cells. These results indicate that MUC1/Muc1 expression by macrophages is predominantly in the M1 subtype, and that MUC1/Muc1 expression in these cells decreases their phagocytic activity in an antiinflammatory manner.

  4. Activated macrophages containing tumor marker in colon carcinoma: immunohistochemical proof of a concept.

    PubMed

    Faber, T J E; Japink, D; Leers, M P G; Sosef, M N; von Meyenfeldt, M F; Nap, M

    2012-04-01

    The presence of carcinoembryonic antigen (CEA)-containing activated macrophages has been demonstrated in peripheral blood from patients with colorectal carcinoma. Macrophages migrate from the circulation into the tissue, phagocytose debris, and return to the bloodstream. Hence it seems likely that activated macrophages containing tumor debris, i.e., tumor marker, are present in the stroma of colorectal carcinoma. After phagocytosis, they could follow a hematogenic or lymphogenic route to the peripheral blood. The aim of this study is to assess the presence of tumor marker-containing activated macrophages in the stroma of colon carcinoma and in regional lymph nodes. From 10 cases of colon carcinoma, samples of tumor tissue and metastasis-free lymph nodes were cut in serial sections and stained for CD68 to identify macrophages and for CEA, cytokeratin, or M30 presence. Slides were digitalised and visually inspected using two monitors, comparing the CD68 stain to the tumor marker stain to evaluate the presence of tumor marker-positive macrophages. Macrophages containing tumor marker could be identified in tumor stroma and in metastasis-free regional lymph nodes. The distribution varied for the different markers, CEA-positive macrophages being most abundant. The presence of macrophages containing tumor marker in the tumor stroma and lymph nodes from patients with colon carcinoma could be confirmed in this series using serial immunohistochemistry. This finding supports the concept of activated macrophages, after phagocytosing cell debris, being transported or migrating through the lymphatic system. These results support the potential of tumor marker-containing macrophages to serve as a marker for diagnosis and follow-up of colon cancer patients.

  5. Regulation of Macrophage Motility by the Water Channel Aquaporin-1: Crucial Role of M0/M2 Phenotype Switch

    PubMed Central

    Tyteca, Donatienne; Nishino, Tomoya; Debaix, Huguette; Van Der Smissen, Patrick; N'Kuli, Francisca; Hoffmann, Delia; Cnops, Yvette; Rabolli, Virginie; van Loo, Geert; Beyaert, Rudi; Huaux, François; Devuyst, Olivier; Courtoy, Pierre J.

    2015-01-01

    The water channel aquaporin-1 (AQP1) promotes migration of many cell types. Although AQP1 is expressed in macrophages, its potential role in macrophage motility, particularly in relation with phenotype polarization, remains unknown. We here addressed these issues in peritoneal macrophages isolated from AQP1-deficient mice, either undifferentiated (M0) or stimulated with LPS to orientate towards pro-inflammatory phenotype (classical macrophage activation; M1). In non-stimulated macrophages, ablation of AQP1 (like inhibition by HgCl2) increased by 2–3 fold spontaneous migration in a Src/PI3K/Rac-dependent manner. This correlated with cell elongation and formation of lamellipodia/ruffles, resulting in membrane lipid and F4/80 recruitment to the leading edge. This indicated that AQP1 normally suppresses migration of resting macrophages, as opposed to other cell types. Resting Aqp1-/- macrophages exhibited CD206 redistribution into ruffles and increased arginase activity like IL4/IL13 (alternative macrophage activation; M2), indicating a M0-M2 shift. In contrast, upon M1 orientation by LPS in vitro or peritoneal inflammation in vivo, migration of Aqp1-/- macrophages was reduced. Taken together, these data indicate that AQP1 oppositely regulates macrophage migration, depending on stimulation or not by LPS, and that macrophage phenotypic and migratory changes may be regulated independently of external cues. PMID:25719758

  6. Mechanistic study of macrophage activation by LPS stimulation using fluorescence imaging techinques

    NASA Astrophysics Data System (ADS)

    Lu, Cuixia; Zhou, Feifan; Chen, Wei R.; Xing, Da

    2012-03-01

    Lipopolysaccharide (LPS), a structural component of the outer membrane of gram negative bacteria, has been suggested that stimulates macrophages secrete a wide variety of inflammatory mediators, such as nitric oxide (NO). However, the cellular mechanisms of NO generation in macrophage by LPS stimulation are not well known. In this study, LPS stimulated NO generation in macrophage was determined by measuring fluorescence changes with a NO specific probe DAF-FM DA. Using the fluorescence resonance energy transfer (FRET) techniques, we found an increase of protein kinase C (PKC) activation was dynamically monitored in macrophages treated with LPS. Nuclear factor kappa B (NF-κB) translocated from the cytoplasm to the nucleus in macrophage was measured by confocal laser scanning microscopy. Moreover, the PKC inhibitor GÖ6983 inhibited LPS-stimulated NF-κB activation and NO production. These results indicated that LPS stimulated NF-κB mediated NO production by activating PKC.

  7. Mechanistic study of macrophage activation by LPS stimulation using fluorescence imaging techinques

    NASA Astrophysics Data System (ADS)

    Lu, Cuixia; Zhou, Feifan; Chen, Wei R.; Xing, Da

    2011-11-01

    Lipopolysaccharide (LPS), a structural component of the outer membrane of gram negative bacteria, has been suggested that stimulates macrophages secrete a wide variety of inflammatory mediators, such as nitric oxide (NO). However, the cellular mechanisms of NO generation in macrophage by LPS stimulation are not well known. In this study, LPS stimulated NO generation in macrophage was determined by measuring fluorescence changes with a NO specific probe DAF-FM DA. Using the fluorescence resonance energy transfer (FRET) techniques, we found an increase of protein kinase C (PKC) activation was dynamically monitored in macrophages treated with LPS. Nuclear factor kappa B (NF-κB) translocated from the cytoplasm to the nucleus in macrophage was measured by confocal laser scanning microscopy. Moreover, the PKC inhibitor GÖ6983 inhibited LPS-stimulated NF-κB activation and NO production. These results indicated that LPS stimulated NF-κB mediated NO production by activating PKC.

  8. Mitogen-Activated Protein Kinases and Mitogen Kinase Phosphatase 1: A Critical Interplay in Macrophage Biology

    PubMed Central

    Lloberas, Jorge; Valverde-Estrella, Lorena; Tur, Juan; Vico, Tania; Celada, Antonio

    2016-01-01

    Macrophages are necessary in multiple processes during the immune response or inflammation. This review emphasizes the critical role of the mitogen-activated protein kinases (MAPKs) and mitogen kinase phosphatase-1 (MKP-1) in the functional activities of macrophages. While the phosphorylation of MAPKs is required for macrophage activation or proliferation, MKP-1 dephosphorylates these kinases, thus playing a balancing role in the control of macrophage behavior. MKP-1 is a nuclear-localized dual-specificity phosphatase whose expression is regulated at multiple levels, including at the transcriptional and post-transcriptional level. The regulatory role of MKP-1 in the interplay between MAPK phosphorylation/dephosphorylation makes this molecule a critical regulator of macrophage biology and inflammation. PMID:27446931

  9. Macrophage activation and its role in repair and pathology after spinal cord injury.

    PubMed

    Gensel, John C; Zhang, Bei

    2015-09-04

    The injured spinal cord does not heal properly. In contrast, tissue repair and functional recovery occur after skin or muscle injuries. The reason for this dichotomy in wound repair is unclear but inflammation, and specifically macrophage activation, likely plays a key role. Macrophages have the ability to promote the repair of injured tissue by regulating transitions through different phase of the healing response. In the current review we compare and contrast the healing and inflammatory responses between spinal cord injuries and tissues that undergo complete wound resolution. Through this comparison, we identify key macrophage phenotypes that are inaptly triggered or absent after spinal cord injury and discuss spinal cord stimuli that contribute to this maladaptive response. Sequential activation of classic, pro-inflammatory, M1 macrophages and alternatively activated, M2a, M2b, and M2c macrophages occurs during normal healing and facilitates transitions through the inflammatory, proliferative, and remodeling phases of repair. In contrast, in the injured spinal cord, pro-inflammatory macrophages potentiate a prolonged inflammatory phase and remodeling is not properly initiated. The desynchronized macrophage activation after spinal cord injury is reminiscent of the inflammation present in chronic, non-healing wounds. By refining the role macrophages play in spinal cord injury repair we bring to light important areas for future neuroinflammation and neurotrauma research. This article is part of a Special Issue entitled SI: Spinal cord injury.

  10. Regulation of membrane associated protein kinase C activity by guanine nucleotide in rabbit peritoneal neutrophils

    SciTech Connect

    Huang, C.K.; Devanney, J.F.

    1986-03-05

    Addition of phorbol myristate acetate (PMA) (0.1 ..mu..g/ml) or guanosine-5'-0-(3-thiotriphosphate) (GTP..gamma..S) (10..mu..M) to the membrane fraction from rabbit peritoneal neutrophils results in an increase of phosphorylation of several membrane proteins. To test whether membrane associated protein kinase C is involved in the activation, histone is added to the membrane as a substrate for protein kinase C. Phosphorylation of histone is determined by counting the gel pieces containing histone IIIS after separation from other membrane components by SDS-gel electrophoresis. In the presence of CaC12 (20 ..mu..M), GTP..gamma..S (10 ..mu..M) or PMA (0.1 ..mu..g/ml) stimulates the phosphorylation of histone IIIS (40% to 70% increase). To achieve this effect calcium is required for GTP..gamma..S but not for PMA. The effect of GTP..gamma..S but not PMA is inhibited in membranes obtained from cells pretreated with pertussis toxin. Membrane protein kinase C is solubilized with Triton X-100 (1%) and then applied to a DEAE-52 cellulose column chromatography. Two peaks of protein kinase C activity are observed. Peak one is eluted at 40 mM NaCl, peak two is eluted at 140 mM NaCl. The activity of peak one is stimulated with phosphatidylserine (PS) and PMA but not with PS and calcium. The activity of peak two is stimulated with either PS and PMA or PS and calcium. The results suggest that GTP binding protein is involved in the activation of membrane associated protein kinase C and the kinase may exist in two forms, calcium sensitive and calcium insensitive.

  11. Pinellia ternata lectin exerts a pro-inflammatory effect on macrophages by inducing the release of pro-inflammatory cytokines, the activation of the nuclear factor-κB signaling pathway and the overproduction of reactive oxygen species.

    PubMed

    Yu, Hong-Li; Zhao, Teng-Fei; Wu, Hao; Pan, Yao-Zong; Zhang, Qian; Wang, Kui-Long; Zhang, Chen-Chao; Jin, Yang-Ping

    2015-10-01

    Pinellia ternata (PT) is a widely used traditional Chinese medicine. The raw material has a throat-irritating toxicity that is associated with the PT lectin (PTL). PTL is a monocot lectin isolated from the tubers of PT, which exhibits mouse peritoneal acute inflammatory effects in vivo. The present study aimed to investigate the pro-inflammatory effect of PTL on macrophages. PTL (50 µg/ml)‑stimulated macrophages enhanced the chemotactic activity of neutrophils. PTL (50, 100, 200 and 400 µg/ml) significantly elevated the production of cytokines [tumor necrosis factor‑α (TNF-α) , interleukin (IL)‑1β and IL‑6]. PTL (25, 50 and 100 µg/ml) induced intracellular reactive oxygen species (ROS) overproduction. PTL also caused transfer of p65 from the macrophage cytoplasm to the nucleus and activated the nuclear factor‑κB (NF‑κB) signaling pathway. Scanning electron microscope images revealed severe cell swelling and membrane integrity defection of macrophages following PTL (100 µg/ml) stimulation, which was also associated with inflammation. PTL had pro‑inflammatory activity, involving induced neutrophil migration, cytokine release, ROS overproduction and the activation of the NF-κB signaling pathway, which was associated with the activation of macrophages.

  12. Down-regulation of Stathmin Is Required for the Phenotypic Changes and Classical Activation of Macrophages.

    PubMed

    Xu, Kewei; Harrison, Rene E

    2015-07-31

    Macrophages are important cells of innate immunity with specialized capacity for recognition and elimination of pathogens and presentation of antigens to lymphocytes for adaptive immunity. Macrophages become activated upon exposure to pro-inflammatory cytokines and pathogenic stimuli. Classical activation of macrophages with interferon-γ (IFNγ) and lipopolysaccharide (LPS) triggers a wide range of signaling events and morphological changes to induce the immune response. Our previous microtubule (MT) proteomic work revealed that the stathmin association with MTs is considerably reduced in activated macrophages, which contain significantly more stabilized MTs. Here, we show that there is a global decrease in stathmin levels, an MT catastrophe protein, in activated macrophages using both immunoblotting and immunofluorescent microscopy. This is an LPS-specific response that induces proteasome-mediated degradation of stathmin. We explored the functions of stathmin down-regulation in activated macrophages by generating a stable cell line overexpressing stathmin-GFP. We show that stathmin-GFP overexpression impacts MT stability, impairs cell spreading, and reduces activation-associated phenotypes. Furthermore, overexpressing stathmin reduces complement receptor 3-mediated phagocytosis and cellular activation, implicating a pivotal inhibitory role for stathmin in classically activated macrophages.

  13. High salt reduces the activation of IL-4– and IL-13–stimulated macrophages

    PubMed Central

    Binger, Katrina J.; Gebhardt, Matthias; Heinig, Matthias; Rintisch, Carola; Schroeder, Agnes; Neuhofer, Wolfgang; Hilgers, Karl; Manzel, Arndt; Schwartz, Christian; Kleinewietfeld, Markus; Voelkl, Jakob; Schatz, Valentin; Linker, Ralf A.; Lang, Florian; Voehringer, David; Wright, Mark D.; Hubner, Norbert; Dechend, Ralf; Jantsch, Jonathan; Titze, Jens; Müller, Dominik N.

    2015-01-01

    A high intake of dietary salt (NaCl) has been implicated in the development of hypertension, chronic inflammation, and autoimmune diseases. We have recently shown that salt has a proinflammatory effect and boosts the activation of Th17 cells and the activation of classical, LPS-induced macrophages (M1). Here, we examined how the activation of alternative (M2) macrophages is affected by salt. In stark contrast to Th17 cells and M1 macrophages, high salt blunted the alternative activation of BM-derived mouse macrophages stimulated with IL-4 and IL-13, M(IL-4+IL-13) macrophages. Salt-induced reduction of M(IL-4+IL-13) activation was not associated with increased polarization toward a proinflammatory M1 phenotype. In vitro, high salt decreased the ability of M(IL-4+IL-13) macrophages to suppress effector T cell proliferation. Moreover, mice fed a high salt diet exhibited reduced M2 activation following chitin injection and delayed wound healing compared with control animals. We further identified a high salt–induced reduction in glycolysis and mitochondrial metabolic output, coupled with blunted AKT and mTOR signaling, which indicates a mechanism by which NaCl inhibits full M2 macrophage activation. Collectively, this study provides evidence that high salt reduces noninflammatory innate immune cell activation and may thus lead to an overall imbalance in immune homeostasis. PMID:26485286

  14. Plutonium behavior after pulmonary administration according to solubility properties, and consequences on alveolar macrophage activation.

    PubMed

    Van der Meeren, Anne; Gremy, Olivier; Renault, Daniel; Miroux, Amandine; Bruel, Sylvie; Griffiths, Nina; Tourdes, Françoise

    2012-01-01

    The physico-chemical form in which plutonium enters the body influences the lung distribution and the transfer rate from lungs to blood. In the present study, we evaluated the early lung damage and macrophage activation after pulmonary contamination of plutonium of various preparation modes which produce different solubility and distribution patterns. Whatever the solubility properties of the contaminant, macrophages represent a major retention compartment in lungs, with 42 to 67% of the activity from broncho-alveolar lavages being associated with macrophages 14 days post-contamination. Lung changes were observed 2 and 6 weeks post-contamination, showing inflammatory lesions and accumulation of activated macrophages (CD68 positive) in plutonium-contaminated rats, although no increased proliferation of pneumocytes II (TTF-1 positive cells) was found. In addition, acid phosphatase activity in macrophages from contaminated rats was enhanced 2 weeks post-contamination as compared to sham groups, as well as inflammatory mediator levels (TNF-α, MCP-1, MIP-2 and CINC-1) in macrophage culture supernatants. Correlating with the decrease in activity remaining in macrophages after plutonium contamination, inflammatory mediator production returned to basal levels 6 weeks post-exposure. The production of chemokines by macrophages was evaluated after contamination with Pu of increasing solubility. No correlation was found between the solubility properties of Pu and the activation level of macrophages. In summary, our data indicate that, despite the higher solubility of plutonium citrate or nitrate as compared to preformed colloids or oxides, macrophages remain the main lung target after plutonium contamination and may participate in the early pulmonary damage.

  15. Phenotypic, functional, and plasticity features of classical and alternatively activated human macrophages.

    PubMed

    Tarique, Abdullah A; Logan, Jayden; Thomas, Emma; Holt, Patrick G; Sly, Peter D; Fantino, Emmanuelle

    2015-11-01

    Macrophages are dynamic cells that mature under the influence of signals from the local microenvironment into either classically (M1) or alternatively (M2) activated macrophages with specific functional and phenotypic properties. Although the phenotypic identification of M1 and M2 macrophages is well established in mice, this is less clear for human macrophages. In addition, the persistence and reversibility of polarized human phenotypes is not well established. Human peripheral blood monocytes were differentiated into uncommitted macrophages (M0) and then polarized to M1 and M2 phenotypes using LPS/IFN-γ and IL-4/IL-13, respectively. M1 and M2 were identified as CD64(+)CD80(+) and CD11b(+)CD209(+), respectively, by flow cytometry. Polarized M1 cells secreted IP-10, IFN-γ, IL-8, TNF-α, IL-1β, and RANTES, whereas M2 cells secreted IL-13, CCL17, and CCL18. Functionally, M2 cells were highly endocytic. In cytokine-deficient medium, the polarized macrophages reverted back to the M0 state within 12 days. If previously polarized macrophages were given the alternative polarizing stimulus after 6 days of resting in cytokine-deficient medium, a switch in polarization was seen (i.e., M1 macrophages switched to M2 and expressed CD11b(+)CD209(+) and vice versa). In summary, we report phenotypic identification of human M1 and M2 macrophages, their functional characteristics, and their ability to be reprogrammed given the appropriate stimuli.

  16. Macrophage activation by factors released from acetaminophen-injured hepatocytes: Potential role of HMGB1

    SciTech Connect

    Dragomir, Ana-Cristina; Laskin, Jeffrey D.; Laskin, Debra L.

    2011-06-15

    Toxic doses of acetaminophen (AA) cause hepatocellular necrosis. Evidence suggests that activated macrophages contribute to the pathogenic process; however, the factors that activate these cells are unknown. In these studies, we assessed the role of mediators released from AA-injured hepatocytes in macrophage activation. Treatment of macrophages with conditioned medium (CM) collected 24 hr after treatment of mouse hepatocytes with 5 mM AA (CM-AA) resulted in increased production of reactive oxygen species (ROS). Macrophage expression of heme oxygenase-1 (HO-1) and catalase mRNA was also upregulated by CM-AA, as well as cyclooxygenase (COX)-2 and 12/15-lipoxygenase (LOX). CM-AA also upregulated expression of the proinflammatory chemokines, MIP-1{alpha} and MIP-2. The effects of CM-AA on expression of COX-2, MIP-1{alpha} and MIP-2 were inhibited by blockade of p44/42 MAP kinase, suggesting a biochemical mechanism mediating macrophage activation. Hepatocytes injured by AA were found to release HMGB1, a potent macrophage activator. This was inhibited by pretreatment of hepatocytes with ethyl pyruvate (EP), which blocks HMGB1 release. EP also blocked CM-AA induced ROS production and antioxidant expression, and reduced expression of COX-2, but not MIP-1{alpha} or MIP-2. These findings suggest that HMGB1 released by AA-injured hepatocytes contributes to macrophage activation. This is supported by our observation that expression of the HMGB1 receptor RAGE is upregulated in macrophages in response to CM-AA. These data indicate that AA-injured hepatocytes contribute to the inflammatory environment in the liver through the release of mediators such as HMGB1. Blocking HMGB1/RAGE may be a useful approach to limiting classical macrophage activation and AA-induced hepatotoxicity. - Research Highlights: > These studies analyze macrophage activation by mediators released from acetaminophen-damaged hepatocytes. > Factors released from acetaminophen-injured hepatocytes induce

  17. Morphine Modulates Interleukin-4- or Breast Cancer Cell-induced Pro-metastatic Activation of Macrophages.

    PubMed

    Khabbazi, Samira; Goumon, Yannick; Parat, Marie-Odile

    2015-06-16

    Interactions between cancer cells and stromal cells in the tumour microenvironment play a key role in the control of invasiveness, metastasis and angiogenesis. Macrophages display a range of activation states in specific pathological contexts and alternatively activated (M2) macrophages can promote tumour aggressiveness. Opioids are able to modulate tumour growth and metastasis. We tested whether morphine modulates the activation of macrophages induced by (i) interleukin-4 (IL-4), the prototypical M2 polarization-inducing cytokine, or (ii) coculture with breast cancer cells. We showed that IL-4 causes increased MMP-9 production and expression of the alternative activation markers arginase-1 and MRC-1. Morphine prevented IL-4-induced increase in MMP-9 in a naloxone- and methylnaltrexone-reversible fashion. Morphine also prevented IL-4-elicited alternative activation of RAW264.7 macrophages. Expression of MMP-9 and arginase-1 were increased when RAW264.7 were subjected to paracrine activation by 4T1 cells, and this effect was prevented by morphine via an opioid receptor-mediated mechanism. Morphine further decreased 4T1 breast cancer cell invasion elicited by co-culture with RAW264.7. Reduction of MMP-9 expression and alternative activation of macrophages by morphine was confirmed using mouse bone marrow-derived macrophages. Taken together, our results indicate that morphine may modulate tumour aggressiveness by regulating macrophage protease production and M2 polarization within the tumour microenvironment.

  18. β-glucans from Coriolus versicolor protect mice against S. typhimurium challenge by activation of macrophages.

    PubMed

    Shi, Shao-Hua; Yang, Wen-Tao; Huang, Ke-Yan; Jiang, Yan-Long; Yang, Gui-Lian; Wang, Chun-Feng; Li, Yu

    2016-05-01

    The effects of β-glucans from Coriolus versicolor (CVP), which are extracted from a well-known immune stimulator C. versicolor, have been demonstrated extensively in vitro and in vivo. However, until now, the phagocytic activity has not been elucidated. Hence, the objective of the present study was to identify the antibacterial activity of CVP or CVP-treated macrophages by an analysis of cell cytotoxicity, phagocytic activity, intracellular bacterial survival, macrophage activation, production of nitric oxide (NO) and expression of inducible nitric oxide synthase (iNOS) in CVP-treated macrophages using flow cytometry, RT-PCR, a gentamicin protection assay, a Nitric oxide assay and an iNOS enzymatic activity assay. The results indicate that CVP-treated macrophages can phagocytize and kill bacteria, probably due to the production of NO and iNOS. More importantly, CVP-treated macrophages are effective at protecting mice against the challenge of Salmonella typhimurium. The results of this study suggest that the antibacterial effects of CVP are probably caused by the activation of innate immune cells, especially macrophages, because the activated macrophage produces NO, which kills bacteria. These phenomena indicate the possibility of CVP as a potential alternative for antibiotics against resistant bacteria.

  19. Activator of G-Protein Signaling 3-Induced Lysosomal Biogenesis Limits Macrophage Intracellular Bacterial Infection.

    PubMed

    Vural, Ali; Al-Khodor, Souhaila; Cheung, Gordon Y C; Shi, Chong-Shan; Srinivasan, Lalitha; McQuiston, Travis J; Hwang, Il-Young; Yeh, Anthony J; Blumer, Joe B; Briken, Volker; Williamson, Peter R; Otto, Michael; Fraser, Iain D C; Kehrl, John H

    2016-01-15

    Many intracellular pathogens cause disease by subverting macrophage innate immune defense mechanisms. Intracellular pathogens actively avoid delivery to or directly target lysosomes, the major intracellular degradative organelle. In this article, we demonstrate that activator of G-protein signaling 3 (AGS3), an LPS-inducible protein in macrophages, affects both lysosomal biogenesis and activity. AGS3 binds the Gi family of G proteins via its G-protein regulatory (GoLoco) motif, stabilizing the Gα subunit in its GDP-bound conformation. Elevated AGS3 levels in macrophages limited the activity of the mammalian target of rapamycin pathway, a sensor of cellular nutritional status. This triggered the nuclear translocation of transcription factor EB, a known activator of lysosomal gene transcription. In contrast, AGS3-deficient macrophages had increased mammalian target of rapamycin activity, reduced transcription factor EB activity, and a lower lysosomal mass. High levels of AGS3 in macrophages enhanced their resistance to infection by Burkholderia cenocepacia J2315, Mycobacterium tuberculosis, and methicillin-resistant Staphylococcus aureus, whereas AGS3-deficient macrophages were more susceptible. We conclude that LPS priming increases AGS3 levels, which enhances lysosomal function and increases the capacity of macrophages to eliminate intracellular pathogens.

  20. GEC-derived SFRP5 inhibits Wnt5a-induced macrophage chemotaxis and activation.

    PubMed

    Zhao, Chenghai; Bu, Xianmin; Wang, Wei; Ma, Tingxian; Ma, Haiying

    2014-01-01

    Aberrant macrophage infiltration and activation has been implicated in gastric inflammation and carcinogenesis. Overexpression of Wnt5a and downregulation of SFRP5, a Wnt5a antagonist, were both observed in gastric cancers recently. This study attempted to explore whether Wnt5a/SFRP5 axis was involved in macrophage chemotaxis and activation. It was found that both Wnt5a transfection and recombinant Wnt5a (rWnt5a) treatment upregulated CCL2 expression in macrophages, involving JNK and NFκB signals. Conditioned medium from Wnt5a-treated macrophages promoted macrophage chemotaxis mainly dependent on CCL2. SFRP5 from gastric epithelial cells (GECs) inhibited Wnt5a-induced CCL2 expression and macrophage chemotaxis. In addition, Wnt5a treatment stimulated macrophages to produce inflammatory cytokines and COX-2/PGE2, which was also suppressed by SFRP5 from GECs. These results demonstrate that Wnt5a induces macrophage chemotaxis and activation, which can be blocked by GEC-derived SFRP5, suggesting that Wnt5a overproduction and SFRP5 deficiency in gastric mucosa may together play an important role in gastric inflammation and carcinogenesis.

  1. Cathepsin Activity-Based Probes and Inhibitor for Preclinical Atherosclerosis Imaging and Macrophage Depletion

    PubMed Central

    Abd-Elrahman, Ihab; Kosuge, Hisanori; Wises Sadan, Tommy; Ben-Nun, Yael; Meir, Karen; Rubinstein, Chen; Bogyo, Matthew; McConnell, Michael V.

    2016-01-01

    Background and Purpose Cardiovascular disease is the leading cause of death worldwide, mainly due to an increasing prevalence of atherosclerosis characterized by inflammatory plaques. Plaques with high levels of macrophage infiltration are considered “vulnerable” while those that do not have significant inflammation are considered stable; cathepsin protease activity is highly elevated in macrophages of vulnerable plaques and contributes to plaque instability. Establishing novel tools for non-invasive molecular imaging of macrophages in plaques could aid in preclinical studies and evaluation of therapeutics. Furthermore, compounds that reduce the macrophage content within plaques should ultimately impact care for this disease. Methods We have applied quenched fluorescent cathepsin activity-based probes (ABPs) to a murine atherosclerosis model and evaluated their use for in vivo imaging using fluorescent molecular tomography (FMT), as well as ex vivo fluorescence imaging and fluorescent microscopy. Additionally, freshly dissected human carotid plaques were treated with our potent cathepsin inhibitor and macrophage apoptosis was evaluated by fluorescent microscopy. Results We demonstrate that our ABPs accurately detect murine atherosclerotic plaques non-invasively, identifying cathepsin activity within plaque macrophages. In addition, our cathepsin inhibitor selectively induced cell apoptosis of 55%±10% of the macrophage within excised human atherosclerotic plaques. Conclusions Cathepsin ABPs present a rapid diagnostic tool for macrophage detection in atherosclerotic plaque. Our inhibitor confirms cathepsin-targeting as a promising approach to treat atherosclerotic plaque inflammation. PMID:27532109

  2. Apigenin Attenuates Atherogenesis through Inducing Macrophage Apoptosis via Inhibition of AKT Ser473 Phosphorylation and Downregulation of Plasminogen Activator Inhibitor-2.

    PubMed

    Zeng, Ping; Liu, Bin; Wang, Qun; Fan, Qin; Diao, Jian-Xin; Tang, Jing; Fu, Xiu-Qiong; Sun, Xue-Gang

    2015-01-01

    Macrophage survival is believed to be a contributing factor in the development of early atherosclerotic lesions. Dysregulated apoptosis of macrophages is involved in the inflammatory process of atherogenesis. Apigenin is a flavonoid that possesses various clinically relevant properties such as anti-inflammatory, antiplatelet, and antitumor activities. Here we showed that apigenin attenuated atherogenesis in apoE (-/-) mice in an in vivo test. In vitro experiments suggested that apigenin induced apoptosis of oxidized low density lipoprotein- (OxLDL-) loaded murine peritoneal macrophages (MPMs). Proteomic analysis showed that apigenin reduced the expression of plasminogen activator inhibitor 2 (PAI-2). PAI-2 has antiapoptotic effects in OxLDL-loaded MPMs. Enhancing PAI-2 expression significantly reduced the proapoptosis effects of apigenin. Molecular docking assay with AutoDock software predicted that residue Ser473 of Akt1 is a potential binding site for apigenin. Lentiviral-mediated overexpression of Akt1 wild type weakened the proapoptosis effect of apigenin in OxLDL-loaded MPMs. Collectively, apigenin executes its anti-atherogenic effects through inducing OxLDL-loaded MPMs apoptosis. The proapoptotic effects of apigenin were at least partly attributed to downregulation of PAI-2 through suppressing phosphorylation of AKT at Ser473.

  3. Mangiferin inhibits macrophage classical activation via downregulating interferon regulatory factor 5 expression

    PubMed Central

    Wei, Zhiquan; Yan, Li; Chen, Yixin; Bao, Chuanhong; Deng, Jing; Deng, Jiagang

    2016-01-01

    Mangiferin is a natural polyphenol and the predominant effective component of Mangifera indica Linn. leaves. For hundreds of years, Mangifera indica Linn. leaf has been used as an ingredient in numerous traditional Chinese medicine preparations for the treatment of bronchitis. However, the pharmacological mechanism of mangiferin in the treatment of bronchitis remains to be elucidated. Macrophage classical activation is important role in the process of bronchial airway inflammation, and interferon regulatory factor 5 (IRF5) has been identified as a key regulatory factor for macrophage classical activation. The present study used the THP-1 human monocyte cell line to investigate whether mangiferin inhibits macrophage classical activation via suppressing IRF5 expression in vitro. THP-1 cells were differentiated to macrophages by phorbol 12-myristate 13-acetate. Macrophages were polarized to M1 macrophages following stimulation with lipopolysaccharide (LPS)/interferon-γ (IFN-γ). Flow cytometric analysis was conducted to detect the M1 macrophages. Reverse transcription-quantitative polymerase chain reaction was used to investigate cellular IRF5 gene expression. Levels of proinflammatory cytokines and IRF5 were assessed following cell culture and cellular homogenization using enzyme-linked immunosorbent assay. IRF5 protein and nuclei co-localization was performed in macrophages with laser scanning confocal microscope immunofluorescence analysis. The results of the present study demonstrated that mangiferin significantly inhibits LPS/IFN-γ stimulation-induced classical activation of macrophages in vitro and markedly decreases proinflammatory cytokine release. In addition, cellular IRF5 expression was markedly downregulated. These results suggest that the inhibitory effect of mangiferin on classical activation of macrophages may be exerted via downregulation of cellular IRF5 expression levels. PMID:27277156

  4. Stromal down-regulation of macrophage CD4/CCR5 expression and NF-κB activation mediates HIV-1 non-permissiveness in intestinal macrophages.

    PubMed

    Shen, Ruizhong; Meng, Gang; Ochsenbauer, Christina; Clapham, Paul R; Grams, Jayleen; Novak, Lea; Kappes, John C; Smythies, Lesley E; Smith, Phillip D

    2011-05-01

    Tissue macrophages are derived exclusively from blood monocytes, which as monocyte-derived macrophages support HIV-1 replication. However, among human tissue macrophages only intestinal macrophages are non-permissive to HIV-1, suggesting that the unique microenvironment in human intestinal mucosa renders lamina propria macrophages non-permissive to HIV-1. We investigated this hypothesis using blood monocytes and intestinal extracellular matrix (stroma)-conditioned media (S-CM) to model the exposure of newly recruited monocytes and resident macrophages to lamina propria stroma, where the cells take up residence in the intestinal mucosa. Exposure of monocytes to S-CM blocked up-regulation of CD4 and CCR5 expression during monocyte differentiation into macrophages and inhibited productive HIV-1 infection in differentiated macrophages. Importantly, exposure of monocyte-derived macrophages simultaneously to S-CM and HIV-1 also inhibited viral replication, and sorted CD4+ intestinal macrophages, a proportion of which expressed CCR5+, did not support HIV-1 replication, indicating that the non-permissiveness to HIV-1 was not due to reduced receptor expression alone. Consistent with this conclusion, S-CM also potently inhibited replication of HIV-1 pseudotyped with vesicular stomatitis virus glycoprotein, which provides CD4/CCR5-independent entry. Neutralization of TGF-β in S-CM and recombinant TGF-β studies showed that stromal TGF-β inhibited macrophage nuclear translocation of NF-κB and HIV-1 replication. Thus, the profound inability of intestinal macrophages to support productive HIV-1 infection is likely the consequence of microenvironmental down-regulation of macrophage HIV-1 receptor/coreceptor expression and NF-κB activation.

  5. Alternative activation deprives macrophages of a coordinated defense program to Mycobacterium tuberculosis.

    PubMed

    Kahnert, Antje; Seiler, Peter; Stein, Maik; Bandermann, Silke; Hahnke, Karin; Mollenkopf, Hans; Kaufmann, Stefan H E

    2006-03-01

    A potent Th1 immune response is critical to the control of tuberculosis. The impact of an additive Th2 response on the course of disease has so far been insufficiently characterized, despite increased morbidity after co-infection with Mycobacterium tuberculosis and Th2-eliciting helminths and possible involvement of Th2 polarization in reactivation of latent tuberculosis. Here, we describe the gene expression profile of murine bone marrow-derived macrophages alternatively activated by IL-4 in response to infection with M. tuberculosis. Comparison of transcriptional profiles of infected IL-4- and IFN-gamma-activated macrophages revealed delayed and partially diminished responses to intracellular bacteria in alternatively activated macrophages, characterized by reduced exposure to nitrosative stress and increased iron availability, respectively. Alternative activation of host macrophages correlated with elevated expression of the M. tuberculosis iron storage protein bacterioferritin as well as reduced expression of the mycobactin synthesis genes mbtI and mbtJ. The extracellular matrix-remodeling enzyme matrix metalloproteinase (MMP)-12 was induced in alternatively activated macrophages in vitro, and MMP-12-expressing macrophages were abundant at late, but not early, stages of tuberculosis in murine lungs. Our findings emphasize that alternative activation deprives macrophages of control mechanisms that limit mycobacterial growth in vivo, thus supporting intracellular persistence of M. tuberculosis.

  6. Peritonitis - secondary

    MedlinePlus

    ... Bacteria may enter the peritoneum through a hole (perforation) in an of the organ digestive tract. The ... function tests X-rays or CT scan Peritoneal fluid culture Urinalysis Treatment Often, surgery is needed to ...

  7. Heme oxygenase-2 deletion impairs macrophage function: implication in wound healing.

    PubMed

    Bellner, Lars; Marrazzo, Giuseppina; van Rooijen, Nico; Dunn, Michael W; Abraham, Nader G; Schwartzman, Michal L

    2015-01-01

    Heme oxygenase (HO)-2 deficiency impairs wound healing and exacerbates inflammation following injury. We examine the impact of HO-2 deficiency on macrophage function and the contribution of macrophage HO-2 to inflammatory and repair responses to injury. Corneal epithelial debridement was performed in control and macrophage-depleted HO-2(-/-) and wild-type (WT) mice and in bone marrow chimeras. Peritoneal macrophages were collected for determination of phagocytic activity and classically activated macrophage (M1)-alternatively activated macrophage (M2) polarization. Depletion of macrophages delayed corneal healing (13.2%) and increased neutrophil infiltration (54.1%) by day 4 in WT mice, whereas in HO-2(-/-) mice, it did not worsen the already impaired wound healing and exacerbated inflammation. HO-2(-/-) macrophages displayed an altered M1 phenotype with no significant expression of M2 or M2-like activated cells and a 31.3% reduction in phagocytic capacity that was restored by inducing HO-1 activity or supplementing biliverdin. Macrophage depletion had no effect, whereas adoptive transfer of WT bone marrow improved wound healing (34% on day 4) but did not resolve the exaggerated inflammatory response in HO-2(-/-) mice. These findings indicate that HO-2-deficient macrophages are dysfunctional and that macrophage HO-2 is required for proper macrophage function but is insufficient to correct the impaired healing of the HO-2(-/-) cornea, suggesting that corneal epithelial expression of HO-2 is a key to resolution and repair in wound healing.

  8. Macrophage activation syndrome: why and what should a gastroenterologist know.

    PubMed

    Jayakar, Bijal A; Hashkes, Philip J

    2011-03-01

    We recently treated a patient with adult-onset Still's disease who developed macrophage activation syndrome (MAS) secondary to disseminated histoplasmosis while being treated with adalimumab. The gastroenterology service was consulted early, before diagnosis, as the patient presented with elevated liver enzymes and disseminated intravascular coagulation. MAS is an exaggerated immune response that can develop as a primary condition or secondary to infections, drugs and various diseases, resulting in liver dysfunction, encephalopathy, pancytopenia and disseminated intravascular coagulation. The development of MAS has also been reported in patients with inflammatory bowel disease and post-liver transplantation and has been triggered by medications used by gastroenterologists, particularly sulfasalazine and anti-tumor necrosis factor biologic modifiers. Therefore, we present a review on etiology, pathogenesis, clinical and laboratory features, and treatment of MAS with a focus on gastrointestinal aspects and presentations. MAS is a life threatening condition with a high mortality rate if untreated. Therefore it is important to recognize this condition early. As these patients may occasionally present to gastroenterologists we hope this review will increase awareness of this rare, but serious syndrome.

  9. Mechanisms of particle-induced activation of alveolar macrophages.

    PubMed

    Gercken, G; Berg, I; Dörger, M; Schlüter, T

    1996-11-01

    Bovine alveolar macrophages were exposed in vitro to quartz dusts, metal-containing dusts or silica particles coated with a single metal oxide. The release of reactive oxygen intermediates (ROI) was measured in short-term incubations (90 min). The secretion of both ROI was markedly enhanced by silica particles coated with vanadium oxide and lowered by copper oxide-coated particles. The particle-induced ROI release was significantly decreased by the inhibition of protein kinase C (PKC) as well as phospholipase A2, suggesting the involvement of both enzymes in the NADPH oxidase activation. Quartz dusts induced a transient increase of free cytosolic calcium ion concentration, slight intracellular acidification, and depolarization of the plasma membrane. In the presence of EGTA or verapamil the rise of [Ca2+]i was diminished, suggesting an influx of extracellular calcium ions. The PKC inhibitor GF 109203X did not inhibit the quartz-induced calcium rise, while both the cytosolic acidification and depolarization were prevented. BSA-coating of the quartz particles abolished the calcium influx as well as the decrease of pHi, and possibly hyperpolarized the plasma membrane.

  10. Biological response of tissues with macrophagic activity to titanium dioxide.

    PubMed

    Olmedo, Daniel G; Tasat, Deborah R; Evelson, Pablo; Guglielmotti, María B; Cabrini, Rómulo L

    2008-03-15

    The titanium dioxide layer is composed mainly of anatase and rutile. This layer is prone to break, releasing particles to the milieu. Therefore, corrosion may cause implant failure and body contamination. We have previously shown that commercial anatase-titanium dioxide (TiO(2)-anatase) is deposited in organs with macrophagic activity, transported in the blood by phagocytic-mononuclear cells, and induces an increase in the production of reactive oxygen species (ROS). In this study, we evaluated the effects of rutile-titanium dioxide (TiO(2)-rutile). Male Wistar rats were injected i.p. with a suspension of TiO(2)-rutile powder at a dose of 1.60 g/100 g b.w. Six months postinjection, the presence of Ti was assessed in serum, blood cells, liver, spleen, and lung. Titanium was found in phagocytic mononuclear cells, serum, and in the parenchyma of all the organs tested. TiO(2)-rutile generated a rise in the percentage of reactive cells, which was smaller than that observed when TiO(2)-anatase was employed in a previous study. Although TiO(2)-rutile provoked an augmentation of ROS, it failed to induce damage to membrane lipids, possibly due to an adaptive response. The present study reveals that TiO(2)-rutile is less bioreactive than TiO(2)-anatase.

  11. Macrophage Polarization.

    PubMed

    Murray, Peter J

    2017-02-10

    Macrophage polarization refers to how macrophages have been activated at a given point in space and time. Polarization is not fixed, as macrophages are sufficiently plastic to integrate multiple signals, such as those from microbes, damaged tissues, and the normal tissue environment. Three broad pathways control polarization: epigenetic and cell survival pathways that prolong or shorten macrophage development and viability, the tissue microenvironment, and extrinsic factors, such as microbial products and cytokines released in inflammation. A plethora of advances have provided a framework for rationally purifying, describing, and manipulating macrophage polarization. Here, I assess the current state of knowledge about macrophage polarization and enumerate the major questions about how activated macrophages regulate the physiology of normal and damaged tissues.

  12. Distinctive role of activated tumor-associated macrophages in photosensitizer accumulation

    NASA Astrophysics Data System (ADS)

    Korbelik, Mladen; Krosl, Gorazd

    1995-05-01

    Cells dissociated from tumors (carcinomas and sarcomas) growing subcutaneously in mice that have been administered Photofrin or other photosensitizers were analyzed by flow cytometry. Monoclonal antibodies were used for identification of major cellular populations contained in these tumors. The results demonstrate that a subpopulation of tumor-associated macrophages (TAMs) is unique among tumor cell populations in that it excels in the accumulation of very high levels of photosensitizers. These macrophages showed an increased expression of interleukin 2 receptor, which is indicative of their activated state. since macrophages were reported to concentrate in the periphery of human neoplasms, it is suggested that activates TAMs are the determinants of tumor-localized photosensitizer fluorescence.

  13. Macrophages sense and kill bacteria through carbon monoxide–dependent inflammasome activation

    PubMed Central

    Wegiel, Barbara; Larsen, Rasmus; Gallo, David; Chin, Beek Yoke; Harris, Clair; Mannam, Praveen; Kaczmarek, Elzbieta; Lee, Patty J.; Zuckerbraun, Brian S.; Flavell, Richard; Soares, Miguel P.; Otterbein, Leo E.

    2014-01-01

    Microbial clearance by eukaryotes relies on complex and coordinated processes that remain poorly understood. The gasotransmitter carbon monoxide (CO) is generated by the stress-responsive enzyme heme oxygenase-1 (HO-1, encoded by Hmox1), which is highly induced in macrophages in response to bacterial infection. HO-1 deficiency results in inadequate pathogen clearance, exaggerated tissue damage, and increased mortality. Here, we determined that macrophage-generated CO promotes ATP production and release by bacteria, which then activates the Nacht, LRR, and PYD domains-containing protein 3 (NALP3) inflammasome, intensifying bacterial killing. Bacterial killing defects in HO-1–deficient murine macrophages were restored by administration of CO. Moreover, increased CO levels enhanced the bacterial clearance capacity of human macrophages and WT murine macrophages. CO-dependent bacterial clearance required the NALP3 inflammasome, as CO did not increase bacterial killing in macrophages isolated from NALP3-deficient or caspase-1–deficient mice. IL-1β cleavage and secretion were impaired in HO-1–deficient macrophages, and CO-dependent processing of IL-1β required the presence of bacteria-derived ATP. We found that bacteria remained viable to generate and release ATP in response to CO. The ATP then bound to macrophage nucleotide P2 receptors, resulting in activation of the NALP3/IL-1β inflammasome to amplify bacterial phagocytosis by macrophages. Taken together, our results indicate that macrophage-derived CO permits efficient and coordinated regulation of the host innate response to invading microbes. PMID:25295542

  14. Macrophage activation induced by Brucella DNA suppresses bacterial intracellular replication via enhancing NO production.

    PubMed

    Liu, Ning; Wang, Lin; Sun, Changjiang; Yang, Li; Tang, Bin; Sun, Wanchun; Peng, Qisheng

    2015-12-01

    Brucella DNA can be sensed by TLR9 on endosomal membrane and by cytosolic AIM2-inflammasome to induce proinflammatory cytokine production that contributes to partially activate innate immunity. Additionally, Brucella DNA has been identified to be able to act as a major bacterial component to induce type I IFN. However, the role of Brucella DNA in Brucella intracellular growth remains unknown. Here, we showed that stimulation with Brucella DNA promote macrophage activation in TLR9-dependent manner. Activated macrophages can suppresses wild type Brucella intracellular replication at early stage of infection via enhancing NO production. We also reported that activated macrophage promotes bactericidal function of macrophages infected with VirB-deficient Brucella at the early or late stage of infection. This study uncovers a novel function of Brucella DNA, which can help us further elucidate the mechanism of Brucella intracellular survival.

  15. Calpains promote neutrophil recruitment and bacterial clearance in an acute bacterial peritonitis model.

    PubMed

    Kumar, Vijay; Everingham, Stephanie; Hall, Christine; Greer, Peter A; Craig, Andrew W B

    2014-03-01

    Activation of the innate immune system is critical for clearance of bacterial pathogens to limit systemic infections and host tissue damage. Here, we report a key role for calpain proteases in bacterial clearance in mice with acute peritonitis. Using transgenic mice expressing Cre recombinase primarily in innate immune cells (fes-Cre), we generated conditional capns1 knockout mice. Consistent with capns1 being essential for stability and function of the ubiquitous calpains (calpain-1, calpain-2), peritoneal cells from these mice had reduced levels of calpain-2/capns1, and reduced proteolysis of their substrate selenoprotein K. Using an acute bacterial peritonitis model, we observed impaired bacterial killing within the peritoneum and development of bacteremia in calpain knockout mice. These defects correlated with significant reductions in IL-1α release, neutrophil recruitment, and generation of reactive oxygen species in calpain knockout mice with acute bacterial peritonitis. Peritoneal macrophages from calpain knockout mice infected with enterobacteria ex vivo, were competent in phagocytosis of bacteria, but showed impaired clearance of intracellular bacteria compared with control macrophages. Together, these results implicate calpains as key mediators of effective innate immune responses to acute bacterial infections, to prevent systemic dissemination of bacteria that can lead to sepsis.

  16. Impairing autophagy in retinal pigment epithelium leads to inflammasome activation and enhanced macrophage-mediated angiogenesis

    PubMed Central

    Liu, Jian; Copland, David A.; Theodoropoulou, Sofia; Chiu, Hsi An Amy; Barba, Miriam Durazo; Mak, Ka Wang; Mack, Matthias; Nicholson, Lindsay B.; Dick, Andrew D.

    2016-01-01

    Age-related decreases in autophagy contribute to the progression of age-related macular degeneration (AMD). We have now studied the interaction between autophagy impaired in retinal pigment epithelium (RPE) and the responses of macrophages. We find that dying RPE cells can activate the macrophage inflammasome and promote angiogenesis. In vitro, inhibiting rotenone-induced autophagy in RPE cells elicits caspase-3 mediated cell death. Co-culture of damaged RPE with macrophages leads to the secretion of IL-1β, IL-6 and nitrite oxide. Exogenous IL-6 protects the dysfunctional RPE but IL-1β causes enhanced cell death. Furthermore, IL-1β toxicity is more pronounced in dysfunctional RPE cells showing reduced IRAK3 gene expression. Co-culture of macrophages with damaged RPE also elicits elevated levels of pro-angiogenic proteins that promote ex vivo choroidal vessel sprouting. In vivo, impaired autophagy in the eye promotes photoreceptor and RPE degeneration and recruitment of inflammasome-activated macrophages. The degenerative tissue environment drives an enhanced pro-angiogenic response, demonstrated by increased size of laser-induced choroidal neovascularization (CNV) lesions. The contribution of macrophages was confirmed by depletion of CCR2+ monocytes, which attenuates CNV in the presence of RPE degeneration. Our results suggest that the interplay between perturbed RPE homeostasis and activated macrophages influences key features of AMD development. PMID:26847702

  17. Feline lectin activity is critical for the cellular entry of feline infectious peritonitis virus.

    PubMed

    Regan, Andrew D; Ousterout, David G; Whittaker, Gary R

    2010-08-01

    Feline infectious peritonitis is a lethal disease of felids caused by systemic infection with a feline coronavirus. Here, we report identification and analysis of the feline homologue to the human lectin DC-SIGN and show that it is a coreceptor for virulent strains of serotype 1 and serotype 2 feline coronaviruses.

  18. Treatment of dextran sodium sulfate-induced experimental colitis by adoptive transfer of peritoneal cells.

    PubMed

    Liu, Ting; Ren, Jun; Wang, Wei; Wei, Xia-wei; Shen, Guo-bo; Liu, Yan-tong; Luo, Min; Xu, Guang-chao; Shao, Bin; Deng, Sen-yi; He, Zhi-yao; Liang, Xiao; Liu, Yu; Wen, Yan-Zhu; Xiang, Rong; Yang, Li; Deng, Hong-xin; Wei, Yu-quan

    2015-11-13

    The adoptive transfer of the natural regulatory B cells and macrophages should be a useful treatment for inflammation and autoimmune disease. However, it is usually difficult to isolate these cells from the tissues and expand them. Here, we investigated the feasibility of adoptively transferring peritoneal cells (PCs) as a treatment for DSS-induced colitis. We found that peritoneal cavity can provide an easily accessible site for harvesting enough number of PCs, namely, two-dose PCs for the treatment from a mouse in one operation. Adoptive therapy of these cells from healthy mice or those with disease is effectively in reducing the disease activity score. The natural B cells and macrophages of the infused PCs can selectively migrate to lesion sites and regulate the expression of Stat3, NF-κB, Smad3 and Smad7. Additionally, PCs exert dual activity of IL-10 and TGF-β secreted spontaneously by both peritoneal B cells and macrophages, which in turn enhance the induction of regulatory B cells and Macrophages in microenvironment of inflammation. Moreover, PCs can re-establish immunological tolerance in the OVA-immunized mice. Thus, our findings provide a new strategy for colitis therapy and could be of importance in additional exploration of other inflammation and autoimmune diseases therapy.

  19. Treatment of dextran sodium sulfate-induced experimental colitis by adoptive transfer of peritoneal cells

    PubMed Central

    Liu, Ting; Ren, Jun; Wang, Wei; Wei, Xia-wei; Shen, Guo-bo; Liu, Yan-tong; Luo, Min; Xu, Guang-chao; Shao, Bin; Deng, Sen-yi; He, Zhi-yao; Liang, Xiao; Liu, Yu; Wen, Yan-Zhu; Xiang, Rong; Yang, Li; Deng, Hong-xin; Wei, Yu-quan

    2015-01-01

    The adoptive transfer of the natural regulatory B cells and macrophages should be a useful treatment for inflammation and autoimmune disease. However, it is usually difficult to isolate these cells from the tissues and expand them. Here, we investigated the feasibility of adoptively transferring peritoneal cells (PCs) as a treatment for DSS-induced colitis. We found that peritoneal cavity can provide an easily accessible site for harvesting enough number of PCs, namely, two-dose PCs for the treatment from a mouse in one operation. Adoptive therapy of these cells from healthy mice or those with disease is effectively in reducing the disease activity score. The natural B cells and macrophages of the infused PCs can selectively migrate to lesion sites and regulate the expression of Stat3, NF−κB, Smad3 and Smad7. Additionally, PCs exert dual activity of IL-10 and TGF-β secreted spontaneously by both peritoneal B cells and macrophages, which in turn enhance the induction of regulatory B cells and Macrophages in microenvironment of inflammation. Moreover, PCs can re-establish immunological tolerance in the OVA-immunized mice. Thus, our findings provide a new strategy for colitis therapy and could be of importance in additional exploration of other inflammation and autoimmune diseases therapy. PMID:26565726

  20. Hyponatremia, hypophosphatemia, and hypouricemia in a girl with macrophage activation syndrome.

    PubMed

    Yamazawa, Kazuki; Kodo, Kazuki; Maeda, Jun; Omori, Sayu; Hida, Mariko; Mori, Tetsuya; Awazu, Midori

    2006-12-01

    Macrophage activation syndrome, a life-threatening complication of rheumatic disorders, is accompanied by the overproduction of cytokines. We describe a girl with macrophage activation syndrome complicating systemic-onset juvenile arthritis who developed hyponatremia, hypophosphatemia, and hypouricemia associated with a high level of serum tumor necrosis factor alpha. Renal proximal tubule dysfunction was considered to be the cause, which may be attributable to tumor necrosis factor alpha.

  1. Translational Regulation of Specific mRNAs Controls Feedback Inhibition and Survival during Macrophage Activation

    PubMed Central

    Schott, Johanna; Reitter, Sonja; Philipp, Janine; Haneke, Katharina; Schäfer, Heiner; Stoecklin, Georg

    2014-01-01

    For a rapid induction and efficient resolution of the inflammatory response, gene expression in cells of the immune system is tightly regulated at the transcriptional and post-transcriptional level. The control of mRNA translation has emerged as an important determinant of protein levels, yet its role in macrophage activation is not well understood. We systematically analyzed the contribution of translational regulation to the early phase of the macrophage response by polysome fractionation from mouse macrophages stimulated with lipopolysaccharide (LPS). Individual mRNAs whose translation is specifically regulated during macrophage activation were identified by microarray analysis. Stimulation with LPS for 1 h caused translational activation of many feedback inhibitors of the inflammatory response including NF-κB inhibitors (Nfkbid, Nfkbiz, Nr4a1, Ier3), a p38 MAPK antagonist (Dusp1) and post-transcriptional suppressors of cytokine expression (Zfp36 and Zc3h12a). Our analysis showed that their translation is repressed in resting and de-repressed in activated macrophages. Quantification of mRNA levels at a high temporal resolution by RNASeq allowed us to define groups with different expression patterns. Thereby, we were able to distinguish mRNAs whose translation is actively regulated from mRNAs whose polysomal shifts are due to changes in mRNA levels. Active up-regulation of translation was associated with a higher content in AU-rich elements (AREs). For one example, Ier3 mRNA, we show that repression in resting cells as well as de-repression after stimulation depends on the ARE. Bone-marrow derived macrophages from Ier3 knockout mice showed reduced survival upon activation, indicating that IER3 induction protects macrophages from LPS-induced cell death. Taken together, our analysis reveals that translational control during macrophage activation is important for cellular survival as well as the expression of anti-inflammatory feedback inhibitors that promote the

  2. Characterization of phosphodiesterase 4 in guinea-pig macrophages: multiple activities, association states and sensitivity to selective inhibitors

    PubMed Central

    Kelly, John J; Barnes, Peter J; Giembycz, Mark A

    1998-01-01

    The cyclic AMP phosphodiesterases (PDE) in guinea-pig peritoneal macrophages were isolated, partially characterized and their role in regulating the cyclic AMP content in intact cells evaluated.Differential centrifugation of macrophage lysates revealed that ∼90% of the PDE activity was membrane-bound and exclusively hydrolyzed cyclic AMP. This activity was not removed by KCl (200 mM) but was readily solubilized by the non-ionic detergent, Triton X-100 (1% v/v). Greater than 80% of the hydrolytic activity was suppressed by the PDE4 inhibitors, R-rolipram and nitraquazone with IC50s of 240 and 540 nM, respectively.Anion-exchange chromatography of the total protein extracted from macrophages resolved two major peaks of cyclic AMP PDE activity that were insensitive to cyclic GMP (10 μM), calmodulin (50 units plus 2 mM CaCl2) and a PDE3 inhibitor, SK&F 95654 (10 μM), but were markedly suppressed by RS-rolipram (10 μM). The two peaks of PDE activity were arbitrarily designated CPPDE4α and CPPDE4β with respect to the order from which they were eluted from the column where the prefix, CP, refers to the species, Cavia porcellus.The hydrolysis of cyclic AMP catalyzed by CPPDE4α and CPPDE4β conformed to Michaelis-Menten kinetic behaviour with similar Kms (13.4 and 6.4 μM, respectively).Thermal denaturation of membrane-bound PDE4 at 50°C followed bi-exponential kinetics with t1/2 values of 1.5 and 54.7 min for the first and second components, respectively. In contrast, CPPDE4α and CPPDE4β each decayed mono-exponentially with significantly different thermostabilities (t1/2=2.77 and 1.15 min, respectively).Gel filtration of CPPDE4β separated two peaks of rolipram-sensitive PDE activity. The main peak eluted at a volume indicative of a ∼180 kDa protein but was preceded by a much larger form of the enzyme that had an estimated weight of 750 kDa. Size exclusion chromatography of CPPDE4α resolved a broad peak of activity with molecular weights

  3. Monocyte to macrophage differentiation-associated (MMD) positively regulates ERK and Akt activation and TNF-α and NO production in macrophages.

    PubMed

    Liu, Qiang; Zheng, Jin; Yin, Dan-Dan; Xiang, Jie; He, Fei; Wang, Yao-Chun; Liang, Liang; Qin, Hong-Yan; Liu, Li; Liang, Ying-Min; Han, Hua

    2012-05-01

    Macrophage activation is modulated by both environmental cues and endogenous programs. In the present study, we investigated the role of a PAQR family protein, monocyte to macrophage differentiation-associated (MMD), in macrophage activation and unveiled its underlying molecular mechanism. Our results showed that while MMD expression could be detected in all tissues examined, its expression level is significantly up-regulated upon monocyte differentiation. Within cells, EGFP-MMD fusion protein could be co-localized to endoplasmic reticulum, mitochondria, Golgi apparatus, but not lysosomes and cytoplasm. MMD expression is up-regulated in macrophages after LPS stimulation, and this might be modulated by RBP-J, the critical transcription factor of Notch signaling. Overexpression of MMD in macrophages increased the production of TNF-α and NO upon LPS stimulation. We found that MMD overexpression enhanced ERK1/2 and Akt phosphorylation in macrophages after LPS stimulation. Blocking Erk or Akt by pharmacological agent reduced TNF-α or NO production in MMD-overexpressing macrophages, respectively. These results suggested that MMD modulates TNF-α and NO production in macrophages, and this process might involves Erk or Akt.

  4. The Dipeptidyl Peptidases 4, 8, and 9 in Mouse Monocytes and Macrophages: DPP8/9 Inhibition Attenuates M1 Macrophage Activation in Mice.

    PubMed

    Waumans, Yannick; Vliegen, Gwendolyn; Maes, Lynn; Rombouts, Miche; Declerck, Ken; Van Der Veken, Pieter; Vanden Berghe, Wim; De Meyer, Guido R Y; Schrijvers, Dorien; De Meester, Ingrid

    2016-02-01

    Atherosclerosis remains the leading cause of death in Western countries. Dipeptidyl peptidase (DPP) 4 has emerged as a novel target for the prevention and treatment of atherosclerosis. Family members DPP8 and 9 are abundantly present in macrophage-rich regions of atherosclerotic plaques, and DPP9 inhibition attenuates activation of human M1 macrophages in vitro. Studying this family in a mouse model for atherosclerosis would greatly advance our knowledge regarding their potential as therapeutic targets. We found that DPP4 is downregulated during mouse monocyte-to-macrophage differentiation. DPP8 and 9 expression seems relatively low in mouse monocytes and macrophages. Viability of primary mouse macrophages is unaffected by DPP4 or DPP8/9 inhibition. Importantly, DPP8/9 inhibition attenuates macrophage activation as IL-6 secretion is significantly decreased. Mouse macrophages respond similarly to DPP inhibition, compared to human macrophages. This shows that the mouse could become a valid model species for the study of DPPs as therapeutic targets in atherosclerosis.

  5. Model-Based Characterization of Inflammatory Gene Expression Patterns of Activated Macrophages

    PubMed Central

    Ehlting, Christian; Thomas, Maria; Zanger, Ulrich M.; Sawodny, Oliver; Häussinger, Dieter; Bode, Johannes G.

    2016-01-01

    Macrophages are cells with remarkable plasticity. They integrate signals from their microenvironment leading to context-dependent polarization into classically (M1) or alternatively (M2) activated macrophages, representing two extremes of a broad spectrum of divergent phenotypes. Thereby, macrophages deliver protective and pro-regenerative signals towards injured tissue but, depending on the eliciting damage, may also be responsible for the generation and aggravation of tissue injury. Although incompletely understood, there is emerging evidence that macrophage polarization is critical for these antagonistic roles. To identify activation-specific expression patterns of chemokines and cytokines that may confer these distinct effects a systems biology approach was applied. A comprehensive literature-based Boolean model was developed to describe the M1 (LPS-activated) and M2 (IL-4/13-activated) polarization types. The model was validated using high-throughput transcript expression data from murine bone marrow derived macrophages. By dynamic modeling of gene expression, the chronology of pathway activation and autocrine signaling was estimated. Our results provide a deepened understanding of the physiological balance leading to M1/M2 activation, indicating the relevance of co-regulatory signals at the level of Akt1 or Akt2 that may be important for directing macrophage polarization. PMID:27464342

  6. High salt primes a specific activation state of macrophages, M(Na).

    PubMed

    Zhang, Wu-Chang; Zheng, Xiao-Jun; Du, Lin-Juan; Sun, Jian-Yong; Shen, Zhu-Xia; Shi, Chaoji; Sun, Shuyang; Zhang, Zhiyuan; Chen, Xiao-Qing; Qin, Mu; Liu, Xu; Tao, Jun; Jia, Lijun; Fan, Heng-Yu; Zhou, Bin; Yu, Ying; Ying, Hao; Hui, Lijian; Liu, Xiaolong; Yi, Xianghua; Liu, Xiaojing; Zhang, Lanjing; Duan, Sheng-Zhong

    2015-08-01

    High salt is positively associated with the risk of many diseases. However, little is known about the mechanisms. Here we showed that high salt increased proinflammatory molecules, while decreased anti-inflammatory and proendocytic molecules in both human and mouse macrophages. High salt also potentiated lipopolysaccharide-induced macrophage activation and suppressed interleukin 4-induced macrophage activation. High salt induced the proinflammatory aspects by activating p38/cFos and/or Erk1/2/cFos pathways, while inhibited the anti-inflammatory and proendocytic aspects by Erk1/2/signal transducer and activator of transcription 6 pathway. Consistent with the in vitro results, high-salt diet increased proinflammatory gene expression of mouse alveolar macrophages. In mouse models of acute lung injury, high-salt diet aggravated lipopolysaccharide-induced pulmonary macrophage activation and inflammation in lungs. These results identify a novel macrophage activation state, M(Na), and high salt as a potential environmental risk factor for lung inflammation through the induction of M(Na).

  7. Macrophages from disease resistant B2 haplotype chickens activate T lymphocytes more effectively than macrophages from disease susceptible B19 birds.

    PubMed

    Collisson, Ellen; Griggs, Lisa; Drechsler, Yvonne

    2017-02-01

    Resistance to respiratory pathogens, including coronavirus-induced infection and clinical illness in chickens has been correlated with the B (MHC) complex and differential ex vivo macrophage responses. In the current study, in vitro T lymphocyte activation measured by IFNγ release was significantly higher in B2 versus B19 haplotypes. AIV infection of macrophages was required to activate T lymphocytes and prior in vivo exposure of chickens to NP AIV plasmid enhanced responses to infected macrophages. This study suggests that the demonstrated T lymphocyte activation is in part due to antigen presentation by the macrophages as well as cytokine release by the infected macrophages, with B2 haplotypes showing stronger activation. These responses were present both in CD4 and CD8 T lymphocytes. In contrast, T lymphocytes stimulated by ConA showed greater IFNγ release of B19 haplotype cells, further indicating the greater responses in B2 haplotypes to infection is due to macrophages, but not T cells. In summary, resistance of B2 haplotype chickens appears to be directly linked to a more vigorous innate immune response and the role macrophages play in activating adaptive immunity.

  8. A novel fluorescent probe for the detection of myeloperoxidase activity in atherosclerosis-associated macrophages

    PubMed Central

    Shepherd, Joanna; Hilderbrand, Scott A.; Waterman, Peter; Heinecke, Jay W.; Weissleder, Ralph; Libby, Peter

    2009-01-01

    SUMMARY The myeloperoxidase (MPO)-derived oxidant hypochlorous acid (HOCl/OCl−) is implicated in the pathogenesis of atherosclerosis and other inflammatory states. We have synthesized a novel imaging probe, sulfonaphthoaminophenyl fluorescein (SNAPF), that selectively reacts to HOCl. SNAPF detects HOCl produced by stimulated MPO-expressing cells cultured from human whole blood, as well as HOCl from bone marrow (BM)-derived macrophages isolated from transgenic mice that express human MPO. Two lines of evidence indicate that SNAPF permits the in vivo imaging of HOCl production. First, we used this approach to demonstrate HOCl production by neutrophils in experimental murine peritonitis. Second, we detected HOCl production by MPO expressing cells in human atherosclerotic arteries. Thus, fluorescence reflectance imaging by SNAPF may provide a valuable non-invasive molecular imaging tool for implicating HOCl and MPO in the damage of inflamed tissues. PMID:18022561

  9. Enhancement of Anti-Inflammatory Activity of Curcumin Using Phosphatidylserine-Containing Nanoparticles in Cultured Macrophages.

    PubMed

    Wang, Ji; Kang, Yu-Xia; Pan, Wen; Lei, Wan; Feng, Bin; Wang, Xiao-Juan

    2016-06-20

    Macrophages are one kind of innate immune cells, and produce a variety of inflammatory cytokines in response to various stimuli, such as oxidized low density lipoprotein found in the pathogenesis of atherosclerosis. In this study, the effect of phosphatidylserine on anti-inflammatory activity of curcumin-loaded nanostructured lipid carriers was investigated using macrophage cultures. Different amounts of phosphatidylserine were used in the preparation of curcumin nanoparticles, their physicochemical properties and biocompatibilities were then compared. Cellular uptake of the nanoparticles was investigated using a confocal laser scanning microscope and flow cytometry analysis in order to determine the optimal phosphatidylserine concentration. In vitro anti-inflammatory activities were evaluated in macrophages to test whether curcumin and phosphatidylserine have interactive effects on macrophage lipid uptake behavior and anti-inflammatory responses. Here, we showed that macrophage uptake of phosphatidylserine-containing nanostructured lipid carriers increased with increasing amount of phosphatidylserine in the range of 0%-8%, and decreased when the phosphatidylserine molar ratio reached over 12%. curcumin-loaded nanostructured lipid carriers significantly inhibited lipid accumulation and pro-inflammatory factor production in cultured macrophages, and evidently promoted release of anti-inflammatory cytokines, when compared with curcumin or phosphatidylserine alone. These results suggest that the delivery system using PS-based nanoparticles has great potential for efficient delivery of drugs such as curcumin, specifically targeting macrophages and modulation of their anti-inflammatory functions.

  10. Activation of TLR3/interferon signaling pathway by bluetongue virus results in HIV inhibition in macrophages.

    PubMed

    Dai, Ming; Wang, Xu; Li, Jie-Liang; Zhou, Yu; Sang, Ming; Liu, Jin-Biao; Wu, Jian-Guo; Ho, Wen-Zhe

    2015-12-01

    Bluetongue virus (BTV), a nonenveloped double-stranded RNA virus, is a potent inducer of type Ι interferons in multiple cell systems. In this study, we report that BTV16 treatment of primary human macrophages induced both type I and III IFN expression, resulting in the production of multiple antiviral factors, including myxovirus resistance protein A, 2',5'-oligoadenylate synthetase, and the IFN-stimulated gene 56. Additionally, BTV-treated macrophages expressed increased HIV restriction factors (apolipoprotein B mRNA-editing enzyme catalytic polypeptide 3 G/F/H) and CC chemokines (macrophage inflammatory protein 1-α, macrophage inflammatory protein 1-β, regulated on activation of normal T cell expressed and secreted), the ligands for HIV entry coreceptor CC chemokine receptor type 5. BTV16 also induced the expression of tetherin, which restricts HIV release from infected cells. Furthermore, TLR3 signaling of macrophages by BTV16 resulted in the induction of several anti-HIV microRNAs (miRNA-28, -29a, -125b, -150, -223, and -382). More importantly, the induction of antiviral responses by BTV resulted in significant suppression of HIV in macrophages. These findings demonstrate the potential of BTV-mediated TLR3 activation in macrophage innate immunity against HIV.

  11. Low Dose BCG Infection as a Model for Macrophage Activation Maintaining Cell Viability

    PubMed Central

    Chávez-Galán, Leslie; Vesin, Dominique; Martinvalet, Denis

    2016-01-01

    Mycobacterium bovis BCG, the current vaccine against tuberculosis, is ingested by macrophages promoting the development of effector functions including cell death and microbicidal mechanisms. Despite accumulating reports on M. tuberculosis, mechanisms of BCG/macrophage interaction remain relatively undefined. In vivo, few bacilli are sufficient to establish a mycobacterial infection; however, in vitro studies systematically use high mycobacterium doses. In this study, we analyze macrophage/BCG interactions and microenvironment upon infection with low BCG doses and propose an in vitro model to study cell activation without affecting viability. We show that RAW macrophages infected with BCG at MOI 1 activated higher and sustained levels of proinflammatory cytokines and transcription factors while MOI 0.1 was more efficient for early stimulation of IL-1β, MCP-1, and KC. Both BCG infection doses induced iNOS and NO in a dose-dependent manner and maintained nuclear and mitochondrial structures. Microenvironment generated by MOI 1 induced macrophage proliferation but not MOI 0.1 infection. In conclusion, BCG infection at low dose is an efficient in vitro model to study macrophage/BCG interactions that maintains macrophage viability and mitochondrial structures. This represents a novel model that can be applied to BCG research fields including mycobacterial infections, cancer immunotherapy, and prevention of autoimmunity and allergies. PMID:27833923

  12. Low Dose BCG Infection as a Model for Macrophage Activation Maintaining Cell Viability.

    PubMed

    Chávez-Galán, Leslie; Vesin, Dominique; Martinvalet, Denis; Garcia, Irene

    2016-01-01

    Mycobacterium bovis BCG, the current vaccine against tuberculosis, is ingested by macrophages promoting the development of effector functions including cell death and microbicidal mechanisms. Despite accumulating reports on M. tuberculosis, mechanisms of BCG/macrophage interaction remain relatively undefined. In vivo, few bacilli are sufficient to establish a mycobacterial infection; however, in vitro studies systematically use high mycobacterium doses. In this study, we analyze macrophage/BCG interactions and microenvironment upon infection with low BCG doses and propose an in vitro model to study cell activation without affecting viability. We show that RAW macrophages infected with BCG at MOI 1 activated higher and sustained levels of proinflammatory cytokines and transcription factors while MOI 0.1 was more efficient for early stimulation of IL-1β, MCP-1, and KC. Both BCG infection doses induced iNOS and NO in a dose-dependent manner and maintained nuclear and mitochondrial structures. Microenvironment generated by MOI 1 induced macrophage proliferation but not MOI 0.1 infection. In conclusion, BCG infection at low dose is an efficient in vitro model to study macrophage/BCG interactions that maintains macrophage viability and mitochondrial structures. This represents a novel model that can be applied to BCG research fields including mycobacterial infections, cancer immunotherapy, and prevention of autoimmunity and allergies.

  13. Relationship of MMP-14 and TIMP-3 Expression with Macrophage Activation and Human Atherosclerotic Plaque Vulnerability

    PubMed Central

    Johnson, Jason L.; Jenkins, Nicholas P.; Huang, Wei-Chun; Sala-Newby, Graciela B.; Scholtes, Vincent P. W.; Moll, Frans L.; Pasterkamp, Gerard; Newby, Andrew C.

    2014-01-01

    Matrix metalloproteinase-14 (MMP-14) promotes vulnerable plaque morphology in mice, whereas tissue inhibitor of metalloproteinases-3 (TIMP-3) overexpression is protective. MMP-14hi  TIMP-3lo rabbit foam cells are more invasive and more prone to apoptosis than MMP-14lo  TIMP-3hi cells. We investigated the implications of these findings for human atherosclerosis. In vitro generated macrophages and foam-cell macrophages, together with atherosclerotic plaques characterised as unstable or stable, were examined for expression of MMP-14, TIMP-3, and inflammatory markers. Proinflammatory stimuli increased MMP-14 and decreased TIMP-3 mRNA and protein expression in human macrophages. However, conversion to foam-cells with oxidized LDL increased MMP-14 and decreased TIMP-3 protein, independently of inflammatory mediators and partly through posttranscriptional mechanisms. Within atherosclerotic plaques, MMP-14 was prominent in foam-cells with either pro- or anti-inflammatory macrophage markers, whereas TIMP-3 was present in less foamy macrophages and colocalised with CD206. MMP-14 positive macrophages were more abundant whereas TIMP-3 positive macrophages were less abundant in plaques histologically designated as rupture prone. We conclude that foam-cells characterised by high MMP-14 and low TIMP-3 expression are prevalent in rupture-prone atherosclerotic plaques, independent of pro- or anti-inflammatory activation. Therefore reducing MMP-14 activity and increasing that of TIMP-3 could be valid therapeutic approaches to reduce plaque rupture and myocardial infarction. PMID:25301980

  14. Peritoneal Dialysis

    PubMed Central

    Al-Natour, Mohammed; Thompson, Dustin

    2016-01-01

    Peritoneal dialysis is becoming more important in the management of patients with end-stage renal disease. Because of the efforts of the “Fistula First Breakthrough Initiative,” dialysis venous access in the United States has become focused on promoting arteriovenous fistula creation and reducing the number of patients who start dialysis with a tunneled catheter. This is important because tunneled catheters can lead to infection, endocarditis, and early loss of more long-term access. When planned for, peritoneal dialysis can offer patients the opportunity to start dialysis at home without jeopardizing central access or the possibilities of eventual arteriovenous fistula creation. The purpose of this review is to highlight the indications, contraindications, and procedural methods for implanting peritoneal dialysis catheters in the interventional radiology suite. PMID:27011420

  15. The tumoricidal properties of inflammatory tissue macrophages and multinucleate giant cells.

    PubMed Central

    Poste, G.

    1979-01-01

    Peritoneal exudate cells from C3H/HeN mice infected with bacille Calmette Guérin (BCG) and subcutaneous inflammatory macrophages from uninfected mice exhibit spontaneous cytotoxicity for tumor cells in vitro, but their tumoricidal activity can be increased by incubation in vitro with lymphokines released by mitogen- or antigen-stimulated lymphocytes. Inflammatory macrophages from these sites are only susceptible to activation in vitro by lymphokines for a short period (less than 4 days) following their initial emigration from the circulation to the site of inflammation. The expression of tumoricidal activity by activated macrophages is similarly short-lived (less than 4 days). Once the tumoricidal state is lost it cannot be restored by further incubation with lymphokines in vitro. Fusion of macrophages to form multinucleate giant cells (MGCs) accompanies the loss of tumoricidal activity and the onset of resistance to activation by lymphokines, but the fusion process is not responsible for these changes, since unfused macrophages are similarly affected. Activation and acquisition of tumoricidal properties is confined to young macrophages recruited from the circulation during acute inflammation. Older macrophages and MGCs in chronic inflammatory lesions in which recruitment of new macrophages has ceased are nontumoricidal and are refractory to activation by lymphokines in vitro. These findings are discussed in relation to the efficiency of macrophage-mediated destruction of tumors in vivo and the amplification of macrophage antitumor activity by immunotherapeutic agents. Images Figure 3 Figure 1 Figure 2 PMID:382866

  16. Hyper-Inflammation and Skin Destruction Mediated by Rosiglitazone Activation of Macrophages in IL-6 Deficiency

    PubMed Central

    Das, Lopa M; Rosenjack, Julie; Au, Liemin; Galle, Pia S; Hansen, Morten B; Cathcart, Martha K; McCormick, Thomas S; Cooper, Kevin D; Silverstein, Roy L; Lu, Kurt Q

    2015-01-01

    Injury initiates recruitment of macrophages to support tissue repair; however, excessive macrophage activity may exacerbate tissue damage causing further destruction and subsequent delay in wound repair. Here we show that the peroxisome proliferation–activated receptor-γ agonist, rosiglitazone (Rosi), a medication recently reintroduced as a drug to treat diabetes and with known anti-inflammatory properties, paradoxically generates pro-inflammatory macrophages. This is observed in both IL-6-deficient mice and control wild-type mice experimentally induced to produce high titers of auto-antibodies against IL-6, mimicking IL-6 deficiency in human diseases. IL-6 deficiency when combined with Rosi-mediated upregulation of suppressor of cytokine signaling 3 leads to an altered ratio of nuclear signal transducer and activator of transcription 3/NF-κB that allows hyper-induction of inducible nitric oxide synthase (iNOS). Macrophages activated in this manner cause de novo tissue destruction, recapitulating human chronic wounds, and can be reversed in vivo by recombinant IL-6, blocking macrophage infiltration, or neutralizing iNOS. This study provides insight into an unanticipated paradoxical role of Rosi in mediating hyper-inflammatory macrophage activation significant for diseases associated with IL-6 deficiency. PMID:25184961

  17. Augmentation of macrophage growth-stimulating activity of lipids by their peroxidation

    SciTech Connect

    Yui, S.; Yamazaki, M. )

    1990-02-15

    Previously, we reported that some kinds of lipids (cholesterol esters, triglycerides, and some negatively charged phospholipids) that are constituents of lipoproteins or cell membranes induce growth of peripheral macrophages in vitro. In this paper, we examined the effect of peroxidation of lipids on their macrophage growth-stimulating activity because lipid peroxidation is observed in many pathological states such as inflammation. When phosphatidylserine, one of the phospholipids with growth-stimulating activity, was peroxidized by UV irradiation, its macrophage growth-stimulating activity was augmented in proportion to the extent of its peroxidation. The activity of phosphatidylethanolamine was also increased by UV irradiation. On the other hand, phosphatidylcholine or highly unsaturated free fatty acids, such as arachidonic acid and eicosapentaenoic acid, did not induce macrophage growth irrespective of whether they were peroxidized. The augmented activity of UV-irradiated phosphatidylserine was not affected by the coexistence of an antioxidant, vitamin E or BHT. These results suggest that some phospholipids included in damaged cells or denatured lipoproteins which are scavenged by macrophages in vivo may induce growth of peripheral macrophages more effectively when they are peroxidized by local pathological processes.

  18. Schistosoma mansoni Hemozoin Modulates Alternative Activation of Macrophages via Specific Suppression of Retnla Expression and Secretion

    PubMed Central

    Truscott, Martha; Evans, D. Andrew; Gunn, Matt

    2013-01-01

    The trematode Schistosoma mansoni is one of the etiological agents of schistosomiasis, a key neglected tropical disease responsible for an estimated annual loss of 70 million disability-adjusted life years. Hematophagy represents the primary nutrient acquisition pathway of this parasite, but digestion of hemoglobin also liberates toxic heme. Schistosomes detoxify heme via crystallization into hemozoin, which is subsequently regurgitated into the host's circulation. Here we demonstrate that during experimental schistosomiasis, hemozoin accumulating in the mouse liver is taken up by phagocytes at a time coincident with the development of the egg-induced T-helper 2 (Th2) granulomatous immune response. Furthermore, the uptake of hemozoin also coincides with the hepatic expression of markers of alternative macrophage activation. Alternatively activated macrophages are a key effector cell population associated with protection against schistosomiasis, making hemozoin well placed to play an important immunomodulatory role in this disease. To systematically explore this hypothesis, S. mansoni hemozoin was purified and added to in vitro bone marrow-derived macrophage cultures concurrently exposed to cytokines chosen to reflect the shifting state of macrophage activation in vivo. Macrophages undergoing interleukin-4 (IL-4)-induced alternative activation in the presence of hemozoin developed a phenotype specifically lacking in Retnla, a characteristic alternatively activated macrophage product associated with regulation of Th2 inflammatory responses. As such, in addition to its important detoxification role during hematophagy, we propose that schistosome hemozoin also provides a potent immunomodulatory function in the coevolved network of host-parasite relationships during schistosomiasis. PMID:23090958

  19. Statin attenuates experimental anti-glomerular basement membrane glomerulonephritis together with the augmentation of alternatively activated macrophages.

    PubMed

    Fujita, Emiko; Shimizu, Akira; Masuda, Yukinari; Kuwahara, Naomi; Arai, Takashi; Nagasaka, Shinya; Aki, Kaoru; Mii, Akiko; Natori, Yasuhiro; Iino, Yasuhiko; Katayama, Yasuo; Fukuda, Yuh

    2010-09-01

    Macrophages are heterogeneous and include classically activated M1 and alternatively activated M2 macrophages, characterized by pro- and anti-inflammatory functions, respectively. Macrophages that express heme oxygenase-1 also exhibit anti-inflammatory effects. We assessed the anti-inflammatory effects of statin in experimental anti-glomerular basement membrane glomerulonephritis and in vitro, focusing on the macrophage heterogeneity. Rats were induced anti-glomerular basement membrane glomerulonephritis and treated with atorvastatin (20 mg/kg/day) or vehicle (control). Control rats showed infiltration of macrophages in the glomeruli at day 3 and developed crescentic glomerulonephritis by day 7, together with increased mRNA levels of the M1 macrophage-associated cytokines, interferon-gamma, tumor necrosis factor-alpha, and interleukin-12. In contrast, statin reduced the level of proteinuria, reduced infiltration of macrophages in glomeruli with suppression of monocyte chemotactic protein-1 expression, and inhibited the formation of necrotizing and crescentic lesions. The number of glomerular ED3-positive macrophages decreased with down-regulation of M1 macrophage-associated cytokines. Furthermore, statin augmented ED2-positive M2 macrophages with up-regulation of the M2 macrophage-associated chemokines and cytokines, chemokine (C-C motif) Iigand-17 and interleukin-10. Statin also increased the glomerular interleukin-10-expressing heme oxygenase-1-positive macrophages. Statin inhibited macrophage development, and suppressed ED3-positive macrophages, but augmented ED2-positive macrophages in M2-associated cytokine environment in vitro. We conclude that the anti-inflammatory effects of statin in glomerulonephritis are mediated through inhibition of macrophage infiltration as well as augmentation of anti-inflammatory macrophages.

  20. HCV dsRNA-Activated Macrophages Inhibit HCV Replication in Hepatocytes

    PubMed Central

    Wang, Yizhong; Li, Jieliang; Wang, Xu; Zhou, Yu; Zhang, Ting; Ho, Wenzhe

    2015-01-01

    Background: Macrophages play critical roles in innate immune response in the liver. Whether macrophages participate in liver innate immunity against HCV replication is poorly understood Objectives: The aim of this study was to investigate the role of macrophages in liver innate immunity against HCV replication. Materials and Methods: Freshly isolated monocytes were purified from peripheral blood of healthy adult donors. Macrophages refer to 7-day-cultured monocytes in vitro. A hepatoma cell line (Huh7) was infected with HCV JFH-1 to generate in vitro HCV infectious system. RT-PCR was used to determine HCV RNA and mRNA levels of genes expression. ELISA was used to measure the protein level of interferon-α (IFN-α) and western blot was used to determine protein expression level of Toll-like receptor 3 (TLR3). Results: HCV dsRNA induced the expression of type I IFN (IFN-α/β) in monocyte-derived macrophages. HCV dsRNA also induced the expression of TLR3 and IFN regulatory factor-7 (IRF-7), the key regulators of the IFN signaling pathway. When HCV JFH-1-infected Huh7 cells were co-cultured with macrophages activated with HCV dsRNA or incubated in media conditioned with supernatant (SN) from HCV dsRNA-activated macrophages, HCV replication was significantly suppressed. This macrophage SN action on HCV inhibition was mediated through type I IFN, which was evidenced by the observation that antibody to type I IFN receptor could neutralize the macrophages-mediated anti-HCV effect. The role of type I IFN in macrophages-mediated anti-HCV activity is further supported by the observation that HCV dsRNA-activated macrophages SN treatment induced the expression of several IFN-stimulated genes (ISGs), ISG15, ISG56, OAS-1, OAS-2, MxA and Viperin in HCV-infected Huh7 cells. Conclusions: Macrophages may play an important role in liver innate immunity against HCV replication through a type I IFN-dependent mechanism. PMID:26322111

  1. Macrophage Stimulating Protein (MSP) evokes superoxide anion production by human macrophages of different origin

    PubMed Central

    Brunelleschi, Sandra; Penengo, Lorenza; Lavagno, Luisa; Santoro, Claudio; Colangelo, Donato; Viano, Ilario; Gaudino, Giovanni

    2001-01-01

    Macrophage Stimulating Protein (MSP), a serum factor related to Hepatocyte Growth Factor, was originally discovered to stimulate chemotaxis of murine resident peritoneal macrophages. MSP is the ligand for Ron, a member of the Met subfamily of tyrosine kinase receptors. The effects of MSP on human macrophages and the role played in human pathophysiology have long been elusive.We show here that human recombinant MSP (hrMSP) evokes a dose-dependent superoxide anion production in human alveolar and peritoneal macrophages as well as in monocyte-derived macrophages, but not in circulating human monocytes. Consistently, the mature Ron protein is expressed by the MSP responsive cells but not by the unresponsive monocytes. The respiratory burst evoked by hrMSP is quantitatively higher than the one induced by N-formylmethionyl-leucyl-phenylalanine and similar to phorbol myristate acetate-evoked one.To investigate the mechanisms involved in NADPH oxidase activation, leading to superoxide anion production, different signal transduction inhibitors were used. By using the non selective tyrosine kinase inhibitor genistein, the selective c-Src inhibitor PP1, the tyrosine phosphatase inhibitor sodium orthovanadate, the phosphatidylinositol 3-kinase inhibitor wortmannin, the p38 inhibitor SB203580, the MEK inhibitor PD098059, we demonstrate that hrMSP-evoked superoxide production is mediated by tyrosine kinase activity, requires the activation of Src but not of PI 3-kinase. We also show that MAP kinase and p38 signalling pathways are involved.These results clearly indicate that hrMSP induces the respiratory burst in human macrophages but not in monocytes, suggesting for the MSP/Ron complex a role of activator as well as of possible marker for human mature macrophages. PMID:11704649

  2. Trypanosoma cruzi: modification of macrophage function during infection

    PubMed Central

    1977-01-01

    Infection of mice with Trypanosoma cruzi and subsequent intraperitoneal challenge with heat-killed trypanosomes elicits peritoneal macrophages which display in vitro microbicidal activity against trypomastigotes of T. cruzi. These cells also display other activated properties including rapid spreading, intense membrane activity, secretion of high levels of plasminogen activator, and ingestion mediated by the C3 receptor. An intravenous infection with BCG, followed by an intraperitoneal challenge with mycobacterial antigens brings about macrophages with similar properties. These criteria of macrophage activation were compared in normal and BCG- or T. cruzi-immune mice, with or without an intraperitoneal challenge with specific or unrelated antigens. Trypanocidal activity is displayed by both BCG- and T. cruzi-immune macrophages after intraperitoneal challenge with either antigen. Resident-immune macrophages from both T. cruzi- and BCG-infected mice show a trypanostatic, rather than trypanocidal activity. Macrophages from noninfected mice, challenged with the same antigens, show neither trypanostatic nor trypanocidal activity. Increased secretion of plasminogen activator shows a definite immunological specificity. Challenge with the specific antigen induces the appearance of macrophages secreting high levels of plasminogen activator, while unrelated antigens induce much smaller levels. Noninfected mice challenged with the same antigens do not display any enchancement in secretion. In contrast, increased spreading and phagocytosis mediated by the complement receptor are also displayed by cells from noninfected mice challenged with any of the agents tested. PMID:327012

  3. Oral administration of lipopolysaccharides activates B-1 cells in the peritoneal cavity and lamina propria of the gut and induces autoimmune symptoms in an autoantibody transgenic mouse

    PubMed Central

    1994-01-01

    About a half of the antierythrocyte autoantibody transgenic (autoAb Tg) mice, in which almost all B cells are detected in the spleen, lymph nodes, and Peyer's patches, but not in the peritoneal cavity, suffer from autoimmune hemolytic anemia. The occurrence of this disease is strongly linked to production of autoAb by activated peritoneal B-1 cells in the Tg mice. In this study, we have shown that oral administration of lipopolysaccharides (LPS) activated B-1 cells in the lamina propria of the gut as well as the peritoneal cavity in the healthy Tg mice and induced the autoimmune symptoms in all the Tg mice. The activation of peritoneal and lamina propria B-1 cells by enteric LPS is found not only in the anti-RBC autoAb Tg mice and normal mice but also in the aly mice which congenitally lack lymph nodes and Peyer's patches. These results suggest that B-1 cells in the two locations may form a common pool independent of Peyer's patches and lymph nodes, and can be activated by enteric thymus-independent antigens or polyclonal activators such as LPS. The induction of autoimmune hemolytic anemia in the Tg mice by enteric LPS through the activation of B-1 cells in the lamina propria of gut and in the peritoneal cavity suggests that B-1 cells and bacterial infection may play a pathogenic role in the onset of autoimmune diseases. PMID:8006578

  4. PGC-1β suppresses saturated fatty acid-induced macrophage inflammation by inhibiting TAK1 activation.

    PubMed

    Chen, Hongen; Liu, Yan; Li, Di; Song, Jiayi; Xia, Min

    2016-02-01

    Inflammation of infiltrated macrophages in adipose tissue is a key contributor to the initiation of adipose insulin resistance. These macrophages are exposed to high local concentrations of free fatty acids (FFAs) and can be proinflammatory activated by saturated fatty acids (SFAs). However, the regulatory mechanisms on SFA-induced macrophage inflammation are still elusive. Peroxisome proliferator-activated receptor γ coactivator-1β (PGC-1β) is a member of the PGC-1 family of transcriptional coactivators and has been reported to play a key role in SFAs metabolism and in the regulation of inflammatory signaling. However, it remains unclear whether PGC-1β is involved in SFA-induced macrophage inflammation. In this study, we found that PGC-1β expression was significantly decreased in response to palmitic acid (PA) in macrophages in a dose dependent manner. PGC-1β inhibited PA induced TNFα, MCP-1, and IL-1β mRNA and protein expressions. Furthermore, PGC-1β significantly antagonized PA induced macrophage nuclear factor-κB (NF-κB) p65 and JUN N-terminal kinase activation. Mechanistically, we revealed that TGF-β-activated kinase 1 (TAK1) and its adaptor protein TAK1 binding protein 1 (TAB1) played a dominant role in the regulatory effects of PGC-1β. We confirmed that PGC-1β inhibited downstream inflammatory signals via binding with TAB1 and thus preventing TAB1/TAK1 binding and TAK1 activation. Finally, we showed that PGC-1β overexpression in PA treated macrophages improved adipocytes PI3K-Akt insulin signaling in a paracrine fashion. Collectively, our results uncovered a novel mechanism on how macrophage inflammation induced by SFAs was regulated and suggest a potential target in the treatment of obesity induced insulin resistance.

  5. In vitro modulation of macrophage functions by 1,1-dimethylhydrazine (UDMH): Possible mechanism for UDMH-induced immuno-enhancement.

    PubMed

    Tarr, M J; Olsen, R G; Bowen, B L; Fertel, R H

    1988-01-01

    The in vitro effects of 1,1-dimethylhydrazine (UDMH) on prostaglandin E(2) (PGE(2)) synthesis, chemiluminescence, phagocytosis, microbicidal activity and chemotaxis in murine enriched-macrophage populations were evaluated. PGE(2) synthesis by resident peritoneal macrophages and chemiluminescence by activated macrophages were markedly suppressed in the presence of UDMH; phagocytosis and microbicidal activity were slightly to moderately suppressed, and chemotaxis was not affected. Two of these functions (PGE(2) synthesis and chemiluminescence) reflect macrophage immunoregulatory properties, and the UDMH-induced abrogation of these functions may be related to the previously reported immuno-enhancing effects of UDMH.

  6. Understanding the Mysterious M2 Macrophage through Activation Markers and Effector Mechanisms

    PubMed Central

    Rőszer, Tamás

    2015-01-01

    The alternatively activated or M2 macrophages are immune cells with high phenotypic heterogeneity and are governing functions at the interface of immunity, tissue homeostasis, metabolism, and endocrine signaling. Today the M2 macrophages are identified based on the expression pattern of a set of M2 markers. These markers are transmembrane glycoproteins, scavenger receptors, enzymes, growth factors, hormones, cytokines, and cytokine receptors with diverse and often yet unexplored functions. This review discusses whether these M2 markers can be reliably used to identify M2 macrophages and define their functional subdivisions. Also, it provides an update on the novel signals of the tissue environment and the neuroendocrine system which shape the M2 activation. The possible evolutionary roots of the M2 macrophage functions are also discussed. PMID:26089604

  7. METEORIN-LIKE is a cytokine associated with barrier tissues and alternatively activated macrophages

    PubMed Central

    Ushach, Irina; Burkhardt, Amanda M.; Martinez, Cynthia; Hevezi, Peter A.; Gerber, Peter Arne; Buhren, Bettina Alexandra; Schrumpf, Holger; Valle-Rios, Ricardo; Vazquez, Monica I.; Homey, Bernhard; Zlotnik, Albert

    2014-01-01

    Cytokines are involved in many functions of the immune system including initiating, amplifying and resolving immune responses. Through bioinformatics analyses of a comprehensive database of gene expression (BIGE: Body Index of Gene Expression) we observed that a small secreted protein encoded by a poorly characterized gene called meteorin-like (METRNL), is highly expressed in mucosal tissues, skin and activated macrophages. Further studies indicate that Metrnl is produced by Alternatively Activated Macrophages (AAM) and M-CSF cultured bone marrow macrophages (M2-like macrophages). In the skin, METRNL is expressed by resting fibroblasts and IFNγ-treated keratinocytes. A screen of human skin-associated diseases showed significant over-expression of METRNL in psoriasis, prurigo nodularis, actinic keratosis and atopic dermatitis. METRNL is also up-regulated in synovial membranes of human rheumatoid arthritis. Taken together, these results indicate that Metrnl represents a novel cytokine, which is likely involved in both innate and acquired immune responses. PMID:25486603

  8. Functional Activity of Monocytes and Macrophages in HTLV-1 Infected Subjects

    PubMed Central

    Amorim, Camila F.; Souza, Anselmo S.; Diniz, Angela G.; Carvalho, Natália B.; Santos, Silvane B.; Carvalho, Edgar M.

    2014-01-01

    The Human T lymphotropic virus type-1 (HTLV-1) infects predominantly T cells, inducing proliferation and lymphocyte activation. Additionally, HTLV-1 infected subjects are more susceptible to other infections caused by other intracellular agents. Monocytes/macrophages are important cells in the defense against intracellular pathogens. Our aims were to determine the frequency of monocytes subsets, expression of co-stimulatory molecules in these cells and to evaluate microbicidal ability and cytokine and chemokine production by macrophages from HTLV-1 infected subjects. Participants were 23 HTLV-1 carriers (HC), 22 HAM/TSP patients and 22 healthy subjects (HS) not infected with HTLV-1. The frequencies of monocyte subsets and expression of co-stimulatory molecules were determined by flow cytometry. Macrophages were infected with L. braziliensis or stimulated with LPS. Microbicidal activity of macrophages was determined by optic microscopy. Cytokines/chemokines from macrophage supernatants were measured by ELISA. HAM/TSP patients showed an increase frequency of intermediate monocytes, but expression of co-stimulatory molecules was similar between the groups. Macrophages from HTLV-1 infected individuals were infected with L. braziliensis at the same ratio than macrophages from HS, and all the groups had the same ability to kill Leishmania parasites. However, macrophages from HTLV-1 infected subjects produced more CXCL9 and CCL5, and less IL-10 than cells from HS. While there was no correlation between IFN-γ and cytokine/chemokine production by macrophages, there was a correlation between proviral load and TNF and CXCL10. These data showed a dissociation between the inflammatory response and microbicidal ability of macrophages from HTLV-1 infected subjects. While macrophages ability to kill an intracellular pathogen did not differ among HTLV-1 infected subjects, these cells secreted high amount of chemokines even in unstimulated cultures. Moreover the increasing

  9. Contribution of alternatively activated macrophages to allergic lung inflammation: a tale of mice and men.

    PubMed

    Dasgupta, Preeta; Keegan, Achsah D

    2012-01-01

    The concept that macrophages play an active role in inflammatory responses began its development in the late 1800s with the now iconic studies by Elie Metchnikoff using starfish larvae and Daphnia [reviewed in Kaufmann SHE: Nat Immunol 2008;9:705-712 and Cavaillon JM: J Leukoc Biol 2011;90:413-424]. Based on his observation of the phagocyte response to a foreign body (rose thorn) and yeast, he proposed that phagocytes acted in host defense and were active participants in the inflammatory process. Flash forward more than 100 years and we find that these basic tenets hold true. However, it is now appreciated that macrophages come in many different flavors and can adopt a variety of nuanced phenotypes depending on the tissue environment in which the macrophage is found. In this brief review, we discuss the role of one type of macrophage termed the alternatively activated macrophage (AAM), also known as the M2 type of macrophage, in regulating allergic lung inflammation and asthma. Recent studies using mouse models of allergic lung inflammation and samples from human asthma patients contribute to the emerging concept that AAMs are not just bystanders of the interleukin (IL)-4- and IL-13-rich environment found in allergic asthma but are also active players in orchestrating allergic lung disease.

  10. ROS-responsive activatable photosensitizing agent for imaging and photodynamic therapy of activated macrophages.

    PubMed

    Kim, Hyunjin; Kim, Youngmi; Kim, In-Hoo; Kim, Kyungtae; Choi, Yongdoo

    2013-01-01

    The optical properties of macrophage-targeted theranostic nanoparticles (MacTNP) prepared from a Chlorin e6 (Ce6)-hyaluronic acid (HA) conjugate can be activated by reactive oxygen species (ROS) in macrophage cells. MacTNP are nonfluorescent and nonphototoxic in their native state. However, when treated with ROS, especially peroxynitrite, they become highly fluorescent and phototoxic. In vitro cell studies show that MacTNP emit near-infrared (NIR) fluorescence inside activated macrophages. The NIR fluorescence is quenched in the extracellular environment. MacTNP are nontoxic in macrophages up to a Ce6 concentration of 10 μM in the absence of light. However, MacTNP become phototoxic upon illumination in a light dose-dependent manner. In particular, significantly higher phototoxic effect is observed in the activated macrophage cells compared to human dermal fibroblasts and non-activated macrophages. The ROS-responsive MacTNP, with their high target-to-background ratio, may have a significant potential in selective NIR fluorescence imaging and in subsequent photodynamic therapy of atherosclerosis with minimum side effects.

  11. Effect of cinnamon water extract on monocyte-to-macrophage differentiation and scavenger receptor activity

    PubMed Central

    2014-01-01

    Background Water soluble cinnamon extract has been shown to increase insulin sensitivity and modulate macrophage activation, a desirable trait for the management of obesity or atherosclerosis. Our present study investigated whether cinnamon water extract (CWE) may influence the differentiation of monocytes into macrophages and the activity of macrophage scavenger receptors, commonly observed in atherosclerotic lesions. Methods We investigated the effect of CWE on the expression of various surface markers and the uptake of acetylated low density lipoprotein (LDL) in phorbol-12-myristate-13-acetate (PMA)-stimulated THP-1 cells. The protein levels of PMA or macrophage-colony stimulating factor (M-CSF)-stimulated type 1 macrophage scavenger receptor (SRA) were analyzed. Finally, the role of extracellar signal-related kinase (ERK) 1/2 in SRA synthesis and the effect of CWE on PMA-stimulated ERK1/2 were determined. Results CWE inhibited the differentiation of monocyte by decreasing the expression of CD11b, CD36 and SRA and the uptake of acetyl LDL. CWE suppressed the upregulation of SRA by M-CSF and modulated ERK1/2 activity, which was required for PMA-induced SRA synthesis. Conclusions Our results demonstrate that CWE was able to interfere with monocyte differentiation and macrophage scavenger activity, indicating its potential in preventing the development of atherosclerotic lesions. PMID:24602512

  12. PARP9 and PARP14 cross-regulate macrophage activation via STAT1 ADP-ribosylation

    PubMed Central

    Iwata, Hiroshi; Goettsch, Claudia; Sharma, Amitabh; Ricchiuto, Piero; Goh, Wilson Wen Bin; Halu, Arda; Yamada, Iwao; Yoshida, Hideo; Hara, Takuya; Wei, Mei; Inoue, Noriyuki; Fukuda, Daiju; Mojcher, Alexander; Mattson, Peter C.; Barabási, Albert-László; Boothby, Mark; Aikawa, Elena; Singh, Sasha A.; Aikawa, Masanori

    2016-01-01

    Despite the global impact of macrophage activation in vascular disease, the underlying mechanisms remain obscure. Here we show, with global proteomic analysis of macrophage cell lines treated with either IFNγ or IL-4, that PARP9 and PARP14 regulate macrophage activation. In primary macrophages, PARP9 and PARP14 have opposing roles in macrophage activation. PARP14 silencing induces pro-inflammatory genes and STAT1 phosphorylation in M(IFNγ) cells, whereas it suppresses anti-inflammatory gene expression and STAT6 phosphorylation in M(IL-4) cells. PARP9 silencing suppresses pro-inflammatory genes and STAT1 phosphorylation in M(IFNγ) cells. PARP14 induces ADP-ribosylation of STAT1, which is suppressed by PARP9. Mutations at these ADP-ribosylation sites lead to increased phosphorylation. Network analysis links PARP9–PARP14 with human coronary artery disease. PARP14 deficiency in haematopoietic cells accelerates the development and inflammatory burden of acute and chronic arterial lesions in mice. These findings suggest that PARP9 and PARP14 cross-regulate macrophage activation. PMID:27796300

  13. Vaccine-induced modulation of gene expression in turbot peritoneal cells. A microarray approach.

    PubMed

    Fontenla, Francisco; Blanco-Abad, Verónica; Pardo, Belén G; Folgueira, Iria; Noia, Manuel; Gómez-Tato, Antonio; Martínez, Paulino; Leiro, José M; Lamas, Jesús

    2016-07-01

    We used a microarray approach to examine changes in gene expression in turbot peritoneal cells after injection of the fish with vaccines containing the ciliate parasite Philasterides dicentrarchi as antigen and one of the following adjuvants: chitosan-PVMMA microspheres, Freund́s complete adjuvant, aluminium hydroxide gel or Matrix-Q (Isconova, Sweden). We identified 374 genes that were differentially expressed in all groups of fish. Forty-two genes related to tight junctions and focal adhesions and/or actin cytoskeleton were differentially expressed in free peritoneal cells. The profound changes in gene expression related to cell adherence and cytoskeleton may be associated with cell migration and also with the formation of cell-vaccine masses and their attachment to the peritoneal wall. Thirty-five genes related to apoptosis were differentially expressed. Although most of the proteins coded by these genes have a proapoptotic effect, others are antiapoptotic, indicating that both types of signals occur in peritoneal leukocytes of vaccinated fish. Interestingly, many of the genes related to lymphocytes and lymphocyte activity were downregulated in the groups injected with vaccine. We also observed decreased expression of genes related to antigen presentation, suggesting that macrophages (which were abundant in the peritoneal cavity after vaccination) did not express these during the early inflammatory response in the peritoneal cavity. Finally, several genes that participate in the inflammatory response were differentially expressed, and most participated in resolution of inflammation, indicating that an M2 macrophage response is generated in the peritoneal cavity of fish one day post vaccination.

  14. High and low molecular weight hyaluronic acid differentially influence macrophage activation.

    PubMed

    Rayahin, Jamie E; Buhrman, Jason S; Zhang, Yu; Koh, Timothy J; Gemeinhart, Richard A

    2015-07-13

    Macrophages exhibit phenotypic diversity permitting wide-ranging roles in maintaining physiologic homeostasis. Hyaluronic acid, a major glycosaminoglycan of the extracellular matrix, has been shown to have differential signaling based on its molecular weight. With this in mind, the main objective of this study was to elucidate the role of hyaluronic acid molecular weight on macrophage activation and reprogramming. Changes in macrophage activation were assessed by activation state selective marker measurement, specifically quantitative real time polymerase chain reaction, and cytokine enzyme-linked immunoassays, after macrophage treatment with differing molecular weights of hyaluronic acid under four conditions: the resting state, concurrent with classical activation, and following inflammation involving either classically or alternatively activated macrophages. Regardless of initial polarization state, low molecular weight hyaluronic acid induced a classically activated-like state, confirmed by up-regulation of pro-inflammatory genes, including nos2, tnf, il12b, and cd80, and enhanced secretion of nitric oxide and TNF-α. High molecular weight hyaluronic acid promoted an alternatively activated-like state, confirmed by up regulation of pro-resolving gene transcription, including arg1, il10, and mrc1, and enhanced arginase activity. Overall, our observations suggest that macrophages undergo phenotypic changes dependent on molecular weight of hyaluronan that correspond to either (1) pro-inflammatory response for low molecular weight HA or (2) pro-resolving response for high molecular weight HA. These observations bring significant further understanding of the influence of extracellular matrix polymers, hyaluronic acid in particular, on regulating the inflammatory response of macrophages. This knowledge can be used to guide the design of HA-containing biomaterials to better utilize the natural response to HAs.

  15. High and low molecular weight hyaluronic acid differentially influence macrophage activation

    PubMed Central

    Rayahin, Jamie E.; Buhrman, Jason S.; Zhang, Yu; Koh, Timothy J.; Gemeinhart, Richard A.

    2015-01-01

    Macrophages exhibit phenotypic diversity permitting wide-ranging roles in maintaining physiologic homeostasis. Hyaluronic acid, a major glycosaminoglycan of the extracellular matrix, has been shown to have differential signaling based on its molecular weight. With this in mind, the main objective of this study was to elucidate the role of hyaluronic acid molecular weight on macrophage activation and reprogramming. Changes in macrophage activation were assessed by activation state selective marker measurement, specifically quantitative real time polymerase chain reaction, and cytokine enzyme-linked immunoassays, after macrophage treatment with differing molecular weights of hyaluronic acid under four conditions: the resting state, concurrent with classical activation, and following inflammation involving either classically or alternatively activated macrophages. Regardless of initial polarization state, low molecular weight hyaluronic acid induced a classically activated-like state, confirmed by up-regulation of pro-inflammatory genes, including nos2, tnf, il12b, and cd80, and enhanced secretion of nitric oxide and TNF-α. High molecular weight hyaluronic acid promoted an alternatively activated-like state, confirmed by up regulation of pro-resolving gene transcription, including arg1, il10, and mrc1, and enhanced arginase activity. Overall, our observations suggest that macrophages undergo phenotypic changes dependent on molecular weight of hyaluronan that correspond to either (1) pro-inflammatory response for low molecular weight HA or (2) pro-resolving response for high molecular weight HA. These observations bring significant further understanding of the influence of extracellular matrix polymers, hyaluronic acid in particular, on regulating the inflammatory response of macrophages. This knowledge can be used to guide the design of HA-containing biomaterials to better utilize the natural response to HAs. PMID:26280020