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Sample records for activated macrophages m1

  1. 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.

  2. Effect of macrophage classical (M1) activation on implant-adherent macrophage interactions with Staphylococcus epidermidis: A murine in vitro model system.

    PubMed

    Park, Kyung R; Bryers, James D

    2012-08-01

    A model in vitro system was developed for eliciting classical (M1) activation of surface-adherent murine macrophages, which was then used to study the interaction of the M1 macrophages with Staphylococcus epidermidis. Glass substrata were first covalently grafted with a mixture of methoxy- and biotin-terminated silanated polyethylene glycol. Interferon (IFN)-γ and/or lipopolysaccharide (LPS), ligands known to induce the highly microbicidal M1 activation state in macrophages, were biotinylated and immobilized by way of a streptavidin intermediate to the biotin-PEG base substratum. Assessment of mouse bone marrow-derived macrophage (BMDM) interleukin (IL)-12(p40) and nitric oxide response to the fabricated surfaces confirmed that the model system achieved activation of adherent macrophage: IFN-γ-presenting surfaces primed cells for M1 activation, LPS-presenting surfaces elicited innate activation, and surface presenting a combination of IFN-γ and LPS induced M1 activation. The phagocytic and microbicidal capacity of activated, surface-adherent BMDM was evaluated using S. epidermidis, a bacterial species prevalent in implant-associated infections. Results indicate that M1 activation of implant-adherent macrophages trends towards diminishing their phagocytic capacity, but enhances their microbicidal capacity for S. epidermidis.

  3. Critical Role of Regulator G-Protein Signaling 10 (RGS10) in Modulating Macrophage M1/M2 Activation

    PubMed Central

    Lee, Jae-Kyung; Chung, Jaegwon; Kannarkat, George T.; Tansey, Malú G.

    2013-01-01

    Regulator of G protein signaling 10 (RGS10), a GTPase accelerating protein (GAP) for G alpha subunits, is a negative regulator of NF-κB in microglia. Here, we investigated the role of RGS10 in macrophages, a closely related myeloid-derived cell type. Features of classical versus alternative activation were assessed in Rgs10-/- peritoneal and bone marrow-derived macrophages upon LPS or IL-4 treatments, respectively. Our results showed that Rgs10-/- macrophages produced higher levels of pro-inflammatory cytokines including TNF, IL-1β and IL-12p70 in response to LPS treatment and exerted higher cytotoxicity on dopaminergic MN9D neuroblastoma cells. We also found that Rgs10-/- macrophages displayed a blunted M2 phenotype upon IL-4 priming. Specifically, Rgs10-/- macrophages displayed lower YM1 and Fizz1 mRNA levels as measured by QPCR compared to wild type macrophages upon IL-4 treatment and this response was not attributable to differences in IL-4 receptor expression. Importantly, phagocytic activities of Rgs10-/- macrophages were blunted in response to IL-4 priming and/or LPS treatments. However, there was no difference in chemotaxis between Rgs10-/- and WT macrophages. Our data indicate that Rgs10-/- macrophages displayed dysregulated M1 responses along with blunted M2 alternative activation responses, suggesting that RGS10 plays an important role in determining macrophage activation responses. PMID:24278459

  4. Porphyromonas gingivalis Lipopolysaccharide Weakly Activates M1 and M2 Polarized Mouse Macrophages but Induces Inflammatory Cytokines

    PubMed Central

    Holden, James A.; Attard, Troy J.; Laughton, Katrina M.; Mansell, Ashley; O'Brien-Simpson, Neil M.

    2014-01-01

    Porphyromonas gingivalis is associated with chronic periodontitis, an inflammatory disease of the tooth's supporting tissues. Macrophages are important in chronic inflammatory conditions, infiltrating tissue and becoming polarized to an M1 or M2 phenotype. As responses to stimuli differ between these phenotypes, we investigated the effect of P. gingivalis lipopolysaccharide (LPS) on M1 and M2 macrophages. M1 and M2 polarized macrophages were produced from murine bone marrow macrophages (BMMϕ) primed with gamma interferon (IFN-γ) or interleukin-4 (IL-4), respectively, and incubated with a low or high dose of P. gingivalis LPS or control TLR2 and TLR4 ligands. In M1-Mϕ, the high dose of P. gingivalis LPS (10 μg/ml) significantly increased the expression of CD40, CD86, inducible nitric oxide synthase, and nitric oxide secretion. The low dose of P. gingivalis LPS (10 ng/ml) did not induce costimulatory or antibacterial molecules but did increase the secretion of IL-1α, IL-6, IL-12p40, IL-12p70, and tumor necrosis factor alpha (TNF-α). P. gingivalis LPS marginally increased the expression of CD206 and YM-1, but it did enhance arginase expression by M2-Mϕ. Furthermore, the secretion of the chemokines KC, RANTES, eotaxin, and MCP-1 from M1, M2, and nonpolarized Mϕ was enhanced by P. gingivalis LPS. TLR2/4 knockout macrophages combined with the TLR activation assays indicated that TLR2 is the main activating receptor for P. gingivalis LPS and whole cells. In conclusion, although P. gingivalis LPS weakly activated M1-Mϕ or M2-Mϕ compared to control TLR ligands, it induced the secretion of inflammatory cytokines, particularly TNF-α from M1-Mϕ and IL-10 from M2-Mϕ, as well as chemotactic chemokines from polarized macrophages. PMID:25047849

  5. Vibrio cholerae porin OmpU mediates M1-polarization of macrophages/monocytes via TLR1/TLR2 activation.

    PubMed

    Khan, Junaid; Sharma, Praveen K; Mukhopadhaya, Arunika

    2015-11-01

    Polarization of the monocytes and macrophages toward the M1 and M2 states is important for hosts' defense against the pathogens. Moreover, it plays a crucial role to resolve the overwhelming inflammatory responses that can be harmful to the host. Polarization of macrophages/monocytes can be induced by pathogen-associated molecular patterns (PAMPs). PAMP-mediated monocyte/macrophage polarization is important during the infection, as pathogen can suppress host immune system by altering the polarization status of the macrophages/monocytes. OmpU, an outer membrane porin protein of Vibrio cholerae, possesses the ability to induce pro-inflammatory responses in monocytes/macrophages. It is also able to down-regulate the LPS-mediated activation of the monocytes/macrophages. Such observation leads us to believe that OmpU may induce a state that can be called as M1/M2-intermediate state. In the present study, we evaluated a set of M1 and M2 markers in RAW 264.7 murine macrophage cell line, and THP-1 human monocytic cell line, in response to the purified OmpU protein. We observed that OmpU, as a PAMP, induced M1-polarization by activating the Toll-like receptor (TLR) signaling pathway. OmpU induced formation of TLR1/TLR2-heterodimers. OmpU-mediated TLR-activation led to the MyD88 recruitment to the TLR1/TLR2 complex. MyD88, in turn, recruited IRAK1. Ultimately, OmpU-mediated signaling led to the activation and subsequent nuclear translocation of the NFκB p65 subunit. We also observed that blocking of the TLR1, TLR2, IRAK1, and NFκB affected OmpU-mediated production of M1-associated pro-inflammatory cytokines such as TNFα and IL-6.

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

    PubMed

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

    2015-01-01

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

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

    PubMed Central

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

    2015-01-01

    The roots and rhizomes of Glycyrrhiza species (licorice) have been widely used as natural sweeteners and herbal medicines. The aim of this study is to investigate the effect of glycyrrhizic acid (GA) from licorice on macrophage polarization. Both phenotypic and functional activities of murine bone marrow-derived macrophages (BMDMs) treated by GA were assessed. Our results showed that GA obviously increased the cell surface expression of CD80, CD86, and MHCII molecules. Meanwhile, GA upregulated the expression of CCR7 and the production of TNF-α, IL-12, IL-6, and NO (the markers of classically activated (M1) macrophages), whereas it downregulated the expression of MR, Ym1, and Arg1 (the markers of alternatively activated (M2) macrophage). The functional tests showed that GA dramatically enhanced the uptake of FITC-dextran and E. coli K88 by BMDMs and decreased the intracellular survival of E. coli K88 and S. typhimurium. Moreover, we demonstrated that JNK and NF-κB activation are required for GA-induced NO and M1-related cytokines production, while ERK1/2 pathway exhibits a regulatory effect via induction of IL-10. Together, these findings indicated that GA promoted polarization of M1 macrophages and enhanced its phagocytosis and bactericidal capacity. The results expanded our knowledge about the role of GA in macrophage polarization. PMID:26664149

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

    PubMed Central

    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 SOCS3hi-expressing, but not SOCS1hi-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

  9. 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

  10. PPAR Activation Induces M1 Macrophage Polarization via cPLA2-COX-2 Inhibition, Activating ROS Production against Leishmania mexicana

    PubMed Central

    Díaz-Gandarilla, J. A.; Osorio-Trujillo, C.; Hernández-Ramírez, V. I.; Talamás-Rohana, P.

    2013-01-01

    Defence against Leishmania depends upon Th1 inflammatory response and, a major problem in susceptible models, is the turnoff of the leishmanicidal activity of macrophages with IL-10, IL-4, and COX-2 upregulation, as well as immunosuppressive PGE2, all together inhibiting the respiratory burst. Peroxisome proliferator-activated receptors (PPAR) activation is responsible for macrophages polarization on Leishmania susceptible models where microbicide functions are deactivated. In this paper, we demonstrated that, at least for L. mexicana, PPAR activation, mainly PPARγ, induced macrophage activation through their polarization towards M1 profile with the increase of microbicide activity against intracellular pathogen L. mexicana. PPAR activation induced IL-10 downregulation, whereas the production of proinflammatory cytokines such as TNF-α, IL-1β, and IL-6 remained high. Moreover, PPAR agonists treatment induced the deactivation of cPLA2-COX-2-prostaglandins pathway together with an increase in TLR4 expression, all of whose criteria meet the M1 macrophage profile. Finally, parasite burden, in treated macrophages, was lower than that in infected nontreated macrophages, most probably associated with the increase of respiratory burst in these treated cells. Based on the above data, we conclude that PPAR agonists used in this work induces M1 macrophages polarization via inhibition of cPLA2 and the increase of aggressive microbicidal activity via reactive oxygen species (ROS) production. PMID:23555077

  11. HCV core protein inhibits polarization and activity of both M1 and M2 macrophages through the TLR2 signaling pathway

    PubMed Central

    Zhang, Qianqian; Wang, Yang; Zhai, Naicui; Song, Hongxiao; Li, Haijun; Yang, Yang; Li, Tianyang; Guo, Xiaolin; Chi, Baorong; Niu, Junqi; Crispe, Ian Nicholas; Su, Lishan; Tu, Zhengkun

    2016-01-01

    Hepatitis C virus (HCV) establishes persistent infection in most infected patients, and eventually causes chronic hepatitis, cirrhosis, and hepatocellular carcinoma in some patients. Monocytes and macrophages provide the first line of defense against pathogens, but their roles in HCV infection remains unclear. We have reported that HCV core protein (HCVc) manipulates human blood-derived dendritic cell development. In the present study, we tested whether HCVc affects human blood-derived monocyte differentiating into macrophages. Results showed that HCVc inhibits monocyte differentiation to either M1 or M2 macrophages through TLR2, associated with impaired STATs signaling pathway. Moreover, HCVc inhibits phagocytosis activity of M1 and M2 macrophages, M1 macrophage-induced autologous and allogeneic CD4+ T cell activation, but promotes M2 macrophage-induced autologous and allogeneic CD4+ T cell activation. In conclusion, HCVc inhibits monocyte-derived macrophage polarization via TLR2 signaling, leading to dysfunctions of both M1 and M2 macrophages in chronic HCV infected patients. This may contribute to the mechanism of HCV persistent infection, and suggest that blockade of HCVc might be a novel therapeutic approach to treating HCV infection. PMID:27786268

  12. Exosome-like vesicles derived by Schistosoma japonicum adult worms mediates M1 type immune- activity of macrophage.

    PubMed

    Wang, Lifu; Li, Zhitao; Shen, Jia; Liu, Zhen; Liang, Jinyi; Wu, Xiaoying; Sun, Xi; Wu, Zhongdao

    2015-05-01

    Exosomes are 30-100-nm membrane vesicles of endocytic origin that are released into the extracellular space upon fusion of the multi-vesicular bodies (MVB) with the plasma membrane, while initial studies described that the role of exosomes was a reticulocyte cargo-disposal mechanism allowing remodeling of the plasma membrane during the maturation of reticulocytes to erythrocytes. Recent studies indicate that exosomes are secreted by most cells and pathogens and play an important role in intercellular signaling and exert regulatory function by carrying bioactive molecules. As numerous pathogens, adult worm of Schistosoma japonicum (S. japonicum) reside in mesenteric veins of definitive host including man and mammal animals. It was reported that the worms or the eggs also have specialized secretion systems to export effector proteins or other molecules into host target cells. However, the mechanisms involved remained unclear. This study investigated the isolation of the exosome-like vesicles secreted by S. japonicum adult worms and its immune activity on microphage in vitro. In this report, we identified exosome-based secretion as a new mechanism for protein secretion by S. japonicum. Electron microscopy tomography revealed the previously unidentified ultrastructural detail of exosome-like vesicles with high resolution; they were found to be typical spherical shape and to have a diverse population that varies in size of 30-100 nm. Exosome-like vesicles isolated from S. japonicum contained a significantly different protein compared with debris pelleted and the apoptosis body. We also demonstrate that macrophages were preferentially differentiated into the M1 subtype while being treated with S. japonicum exosome-like vesicles. This study reveals there are exosome-like vesicles derived by S. japonicum adult worms, and the exosome-like vesicles can mediate M1-type immune- activity of macrophage.

  13. Modification of TAK1 by O-linked N-acetylglucosamine facilitates TAK1 activation and promotes M1 macrophage polarization.

    PubMed

    Zhang, Dongmei; Xu, Zhiwei; Tao, Tao; Liu, Xiaojuan; Sun, Xiaolei; Ji, Yuhong; Han, Lijian; Qiu, Huiyuan; Zhu, Guizhou; Shen, Yifen; Zhu, Liang; Shen, Aiguo

    2016-11-01

    Macrophages play many different roles in tissue inflammation and immunity, and the plasticity of macrophage polarization is closely associated with acute inflammatory responses. O-GlcNAcylation is an important type of post-translational modification, which subtly modulates inflammation responses. Transforming growth factor (TGF)-β-activated kinase 1 (TAK1) is a key serine/threonine protein kinase that mediates signals transduced by pro-inflammatory cytokines such as TGF-β, tumor necrosis factor (TNF), and interleukin-1 (IL-1). It is here reported that TGFβ-activated kinase (TAK1) is modified with N-acetylglucosamine (O-GlcNAc) on S427. Both IL-1 and osmotic stress, which are known as the TAK1-signaling inducers, significantly trigger the O-GlcNAcylation of TAK1 in macrophages. By overexpressing wild-type (WT) or S427A TAK1 mutant into macrophages, it was determined that O-GlcNAcylation of TAK1 on S427 is required for T187/S192 phosphorylation and full activation of TAK1 upon stimulation with IL-1α and NaCl. Aborting O-GlcNAcylation of TAK1 on S427 was found to inhibit the downstream JNK and nuclear factor-κB activation and reduce the final amount of cytokines produced in activated macrophages to a great extent. Results also showed that overexpression of the O-GlcNAcylation-deficient mutant of TAK1 promotes LPS-mediated apoptosis in macrophages. Importantly, TAK1 O-GlcNAcylation was found to promote M1 macrophage polarization in activated macrophages. Taken together, these data demonstrate that O-GlcNAcylation of TAK1 on S427 critically regulates the pro-inflammatory activation and M1 polarization of macrophages via modulation of the TAK1/JNK/NF-κB signaling pathway.

  14. Dectin-1 Activation by a Natural Product β-Glucan Converts Immunosuppressive Macrophages into an M1-like Phenotype.

    PubMed

    Liu, Min; Luo, Fengling; Ding, Chuanlin; Albeituni, Sabrin; Hu, Xiaoling; Ma, Yunfeng; Cai, Yihua; McNally, Lacey; Sanders, Mary Ann; Jain, Dharamvir; Kloecker, Goetz; Bousamra, Michael; Zhang, Huang-ge; Higashi, Richard M; Lane, Andrew N; Fan, Teresa W-M; Yan, Jun

    2015-11-15

    Tumor-associated macrophages (TAM) with an alternatively activated phenotype have been linked to tumor-elicited inflammation, immunosuppression, and resistance to chemotherapies in cancer, thus representing an attractive target for an effective cancer immunotherapy. In this study, we demonstrate that particulate yeast-derived β-glucan, a natural polysaccharide compound, converts polarized alternatively activated macrophages or immunosuppressive TAM into a classically activated phenotype with potent immunostimulating activity. This process is associated with macrophage metabolic reprograming with enhanced glycolysis, Krebs cycle, and glutamine utilization. In addition, particulate β-glucan converts immunosuppressive TAM via the C-type lectin receptor dectin-1-induced spleen tyrosine kinase-Card9-Erk pathway. Further in vivo studies show that oral particulate β-glucan treatment significantly delays tumor growth, which is associated with in vivo TAM phenotype conversion and enhanced effector T cell activation. Mice injected with particulate β-glucan-treated TAM mixed with tumor cells have significantly reduced tumor burden with less blood vascular vessels compared with those with TAM plus tumor cell injection. In addition, macrophage depletion significantly reduced the therapeutic efficacy of particulate β-glucan in tumor-bearing mice. These findings have established a new paradigm for macrophage polarization and immunosuppressive TAM conversion and shed light on the action mode of β-glucan treatment in cancer.

  15. Photobiomodulation with 660-nm and 780-nm laser on activated J774 macrophage-like cells: Effect on M1 inflammatory markers.

    PubMed

    Fernandes, Kristianne Porta Santos; Souza, Nadhia Helena Costa; Mesquita-Ferrari, Raquel Agnelli; Silva, Daniela de Fatima Teixeira da; Rocha, Lilia Alves; Alves, Agnelo Neves; Sousa, Kaline de Brito; Bussadori, Sandra Kalil; Hamblin, Michael R; Nunes, Fábio Daumas

    2015-12-01

    M1 profile macrophages exert a major influence on initial tissue repair process. Few days after the occurrence of injury, macrophages in the injured region exhibit a M2 profile, attenuate the effects of the M1 population, and stimulate the reconstruction of the damaged tissue. The different effects of macrophages in the healing process suggest that these cells could be the target of therapeutic interventions. Photobiomodulation has been used to accelerate tissue repair, but little is known regarding its effect on macrophages. In the present study, J774 macrophages were activated to simulate the M1 profile and irradiated with two different sets of laser parameters (780 nm, 70 mW, 2.6J/cm(2), 1.5s and 660 nm, 15 mW, 7.5 J/cm(2), 20s). IL-6, TNF-α, iNOS and COX-2 gene and protein expression were analyzed by RT-qPCR and ELISA. Both lasers were able to reduce TNF-α and iNOS expression, and TNF-α and COX-2 production, although the parameters used for 780 nm laser provided an additional decrease. 660 nm laser parameters resulted in an up-regulation of IL-6 expression and production. These findings imply a distinct, time-dependent modulation by the two different sets of laser parameters, suggesting that the best modulation may involve more than one combination of parameters.

  16. Rapamycin unbalances the polarization of human macrophages to M1.

    PubMed

    Mercalli, Alessia; Calavita, Ines; Dugnani, Erica; Citro, Antonio; Cantarelli, Elisa; Nano, Rita; Melzi, Raffaella; Maffi, Paola; Secchi, Antonio; Sordi, Valeria; Piemonti, Lorenzo

    2013-10-01

    Plasticity is a hallmark of macrophages, and in response to environmental signals these cells undergo different forms of polarized activation, the extremes of which are called classic (M1) and alternative (M2). Rapamycin (RAPA) is crucial for survival and functions of myeloid phagocytes, but its effects on macrophage polarization are not yet studied. To address this issue, human macrophages obtained from six normal blood donors were polarized to M1 or M2 in vitro by lipopolysaccharide plus interferon-γ or interleukin-4 (IL-4), respectively. The presence of RAPA (10 ng/ml) induced macrophage apoptosis in M2 but not in M1. Beyond the impact on survival in M2, RAPA reduced CXCR4, CD206 and CD209 expression and stem cell growth factor-β, CCL18 and CCL13 release. In contrast, in M1 RAPA increased CD86 and CCR7 expression and IL-6, tumour necrosis factor-α and IL-1β release but reduced CD206 and CD209 expression and IL-10, vascular endothelial growth factor and CCL18 release. In view of the in vitro data, we examined the in vivo effect of RAPA monotherapy (0·1 mg/kg/day) in 12 patients who were treated for at least 1 month before islet transplant. Cytokine release by Toll-like receptor 4-stimulated peripheral blood mononuclear cells showed a clear shift to an M1-like profile. Moreover, macrophage polarization 21 days after treatment showed a significant quantitative shift to M1. These results suggest a role of mammalian target of rapamycin (mTOR) into the molecular mechanisms of macrophage polarization and propose new therapeutic strategies for human M2-related diseases through mTOR inhibitor treatment.

  17. Activation of tumor suppressor protein p53 is required for Theiler's murine encephalomyelitis virus-induced apoptosis in M1-D macrophages.

    PubMed

    Son, Kyung-No; Pugazhenthi, Subbiah; Lipton, Howard L

    2009-10-01

    Theiler's murine encephalomyelitis virus (TMEV) is a highly cytolytic picornavirus that persists in the mouse central nervous system (CNS) largely in macrophages with infection maintained by macrophage-to-macrophage spread. Infected macrophages in the CNS undergo apoptosis. We recently showed that M1-D macrophages infected with the low-neurovirulence TMEV BeAn virus became apoptotic through the mitochondrial pathway that is Bax mediated. Our present analyses of the molecular events and signaling pathway(s) culminating in the mitochondrial outer membrane permeabilization that initiates the caspase cascade and apoptosis of BeAn virus-infected M1-D macrophages revealed activation of p38 mitogen-activated protein kinase by 2 to 3 h postinfection (p.i.), followed by phosphorylation of tumor suppressor protein p53 Ser 15 at 3 to 6 h p.i., stabilizing p53 levels until 6 h p.i. Activated p53 upregulated the transcription of proapoptotic puma and noxa genes at 2 to 4 h p.i. and their BH3-only protein expression, followed by the loss of detectable prosurvival Mcl-1 and A1 proteins at 4 to 10 h p.i. Degradation of the prosurvival proteins is known to release Bax, which forms homo-oligomers and translocates into and permeabilizes the mitochondrial outer membrane. Inhibition of phospho-p38 by two specific inhibitors, SB203580 and BIRB796, led to a significant decrease in apoptosis at 10 h p.i., with no effect on virus titers (only SB203580 tested). Together, these data indicate that p53 activation is required for the induction of apoptosis in infected M1-D cells.

  18. Probiotic Bacillus amyloliquefaciens mediate M1 macrophage polarization in mouse bone marrow-derived macrophages.

    PubMed

    Ji, Jian; Hu, Sheng-Lan; Cui, Zhi-Wen; Li, Wei-Fen

    2013-05-01

    Depending on the microenvironment, macrophages can acquire distinct functional phenotypes, referred to as classically activated M1 and M2. M1 macrophages are considered potent effector cells that kill intracellular pathogens, and M2 macrophages promote the resolution of wound healing. In this study, we are interested to know whether probiotic Bacillus amyloliquefaciens (Ba) can induce macrophages polarization. Real-time fluorescence PCR analysis demonstrated that the expression of IL-1β, iNOS, TNF-α and IL-6 genes for M1 macrophages was significantly increased at 1.5 h after probiotic Ba treatment compared to the probiotic Ba-free treatment (P < 0.01), whereas the expression of M2 macrophage marker genes (Arg1, Fizz1, MR, Ym1) was decreased (P < 0.05). Furthermore, the phagocytic activity was dramatically increased in the Ba-treated BMDMs using a FITC-dextran endocytosis assay. Together, these findings indicated that probiotic Ba facilitated polarization of M1 macrophages and enhanced its phagocytic capacity. The results expanded our knowledge about probiotic function-involved macrophage polarization.

  19. Cervical Cancer Cell Supernatants Induce a Phenotypic Switch from U937-Derived Macrophage-Activated M1 State into M2-Like Suppressor Phenotype with Change in Toll-Like Receptor Profile

    PubMed Central

    Sánchez-Reyes, Karina; Bravo-Cuellar, Alejandro; Hernández-Flores, Georgina; Lerma-Díaz, José Manuel; Jave-Suárez, Luis Felipe; Gómez-Lomelí, Paulina; de Celis, Ruth; Aguilar-Lemarroy, Adriana; Domínguez-Rodríguez, Jorge Ramiro; Ortiz-Lazareno, Pablo Cesar

    2014-01-01

    Cervical cancer (CC) is the second most common cancer among women worldwide. Infection with human papillomavirus (HPV) is the main risk factor for developing CC. Macrophages are important immune effector cells; they can be differentiated into two phenotypes, identified as M1 (classically activated) and M2 (alternatively activated). Macrophage polarization exerts profound effects on the Toll-like receptor (TLR) profile. In this study, we evaluated whether the supernatant of human CC cells HeLa, SiHa, and C-33A induces a shift of M1 macrophage toward M2 macrophage in U937-derived macrophages. Results. The results showed that soluble factors secreted by CC cells induce a change in the immunophenotype of macrophages from macrophage M1 into macrophage M2. U937-derived macrophages M1 released proinflammatory cytokines and nitric oxide; however, when these cells were treated with the supernatant of CC cell lines, we observed a turnover of M1 toward M2. These cells increased CD163 and IL-10 expression. The expression of TLR-3, -7, and -9 is increased when the macrophages were treated with the supernatant of CC cells. Conclusions. Our result strongly suggests that CC cells may, through the secretion of soluble factors, induce a change of immunophenotype M1 into M2 macrophages. PMID:25309919

  20. Macrophage Polarisation: an Immunohistochemical Approach for Identifying M1 and M2 Macrophages

    PubMed Central

    Barros, Mário Henrique M.; Hauck, Franziska; Dreyer, Johannes H.; Kempkes, Bettina; Niedobitek, Gerald

    2013-01-01

    Macrophage polarization is increasingly recognised as an important pathogenetic factor in inflammatory and neoplastic diseases. Proinflammatory M1 macrophages promote T helper (Th) 1 responses and show tumoricidal activity. M2 macrophages contribute to tissue repair and promote Th2 responses. CD68 and CD163 are used to identify macrophages in tissue sections. However, characterisation of polarised macrophages in situ has remained difficult. Macrophage polarisation is regulated by transcription factors, pSTAT1 and RBP-J for M1, and CMAF for M2. We reasoned that double-labelling immunohistochemistry for the detection of macrophage markers together with transcription factors may be suitable to characterise macrophage polarisation in situ. To test this hypothesis, we have studied conditions associated with Th1- and Th2-predominant immune responses: infectious mononucleosis and Crohn’s disease for Th1 and allergic nasal polyps, oxyuriasis, wound healing and foreign body granulomas for predominant Th2 response. In all situations, CD163+ cells usually outnumbered CD68+ cells. Moreover, CD163+ cells, usually considered as M2 macrophages, co-expressing pSTAT1 and RBP-J were found in all conditions examined. The numbers of putative M1 macrophages were higher in Th1- than in Th2-associated diseases, while more M2 macrophages were seen in Th2- than in Th1 related disorders. In most Th1-related diseases, the balance of M1 over M2 cells was shifted towards M1 cells, while the reverse was observed for Th2-related conditions. Hierarchical cluster analysis revealed two distinct clusters: cluster I included Th1 diseases together with cases with high numbers of CD163+pSTAT1+, CD68+pSTAT1+, CD163+RBP-J+ and CD68+RBP-J+ macrophages; cluster II comprised Th2 conditions together with cases displaying high numbers of CD163+CMAF+ and CD68+CMAF+ macrophages. These results suggest that the detection of pSTAT1, RBP-J, and CMAF in the context of CD68 or CD163 expression is a suitable tool

  1. Unprimed, M1 and M2 Macrophages Differentially Interact with Porphyromonas gingivalis.

    PubMed

    Lam, Roselind S; O'Brien-Simpson, Neil M; Holden, James A; Lenzo, Jason C; Fong, Shao B; Reynolds, Eric C

    2016-01-01

    Porphyromonas gingivalis is a keystone pathogen in the development of chronic periodontitis. Tissue macrophages are amongst the first immune cells to respond to bacteria and depending on the cytokine profile at the infection site, macrophages are primed to react to infection in different ways. Priming of naive macrophages with IFN-γ produces a classical pro-inflammatory, antibacterial M1 macrophage after TLR ligation, whereas priming with IL-4 induces an anti-inflammatory tissue-repair M2 phenotype. Previous work has shown that M1 are preferentially generated in gingival tissue following infection with P. gingivalis. However, few studies have investigated the interactions of macrophage subsets with P. gingivalis cells. The aim of this study was to determine the ability of naive, M1 and M2 macrophages to phagocytose P. gingivalis and investigate how this interaction affects both the bacterial cell and the macrophage. M1 and M2 macrophages were both found to have enhanced phagocytic capacity compared with that of naive macrophages, however only the naive and M1 macrophages were able to produce a respiratory burst in order to clear the bacteria from the phagosome. P. gingivalis was found to persist in naive and M2, but not M1 macrophages for 24 hours. Phagocytosis of P. gingivalis also induced high levels of TNF-α, IL-12 and iNOS in M1 macrophages, but not in naive or M2 macrophages. Furthermore, infection of macrophages with P. gingivalis at high bacteria to macrophage ratios, while inducing an inflammatory response, was also found to be deleterious to macrophage longevity, with high levels of apoptotic cell death found in macrophages after infection. The activation of M1 macrophages observed in this study may contribute to the initiation and maintenance of a pro-inflammatory state during chronic periodontitis. PMID:27383471

  2. Unprimed, M1 and M2 Macrophages Differentially Interact with Porphyromonas gingivalis

    PubMed Central

    Lenzo, Jason C.; Fong, Shao B.; Reynolds, Eric C.

    2016-01-01

    Porphyromonas gingivalis is a keystone pathogen in the development of chronic periodontitis. Tissue macrophages are amongst the first immune cells to respond to bacteria and depending on the cytokine profile at the infection site, macrophages are primed to react to infection in different ways. Priming of naive macrophages with IFN-γ produces a classical pro-inflammatory, antibacterial M1 macrophage after TLR ligation, whereas priming with IL-4 induces an anti-inflammatory tissue-repair M2 phenotype. Previous work has shown that M1 are preferentially generated in gingival tissue following infection with P. gingivalis. However, few studies have investigated the interactions of macrophage subsets with P. gingivalis cells. The aim of this study was to determine the ability of naive, M1 and M2 macrophages to phagocytose P. gingivalis and investigate how this interaction affects both the bacterial cell and the macrophage. M1 and M2 macrophages were both found to have enhanced phagocytic capacity compared with that of naive macrophages, however only the naive and M1 macrophages were able to produce a respiratory burst in order to clear the bacteria from the phagosome. P. gingivalis was found to persist in naive and M2, but not M1 macrophages for 24 hours. Phagocytosis of P. gingivalis also induced high levels of TNF-α, IL-12 and iNOS in M1 macrophages, but not in naive or M2 macrophages. Furthermore, infection of macrophages with P. gingivalis at high bacteria to macrophage ratios, while inducing an inflammatory response, was also found to be deleterious to macrophage longevity, with high levels of apoptotic cell death found in macrophages after infection. The activation of M1 macrophages observed in this study may contribute to the initiation and maintenance of a pro-inflammatory state during chronic periodontitis. PMID:27383471

  3. Myeloid cell-derived inducible nitric oxide synthase suppresses M1 macrophage polarization.

    PubMed

    Lu, Geming; Zhang, Ruihua; Geng, Shuo; Peng, Liang; Jayaraman, Padmini; Chen, Chun; Xu, Feifong; Yang, Jianjun; Li, Qin; Zheng, Hao; Shen, Kimberly; Wang, Juan; Liu, Xiyu; Wang, Weidong; Zheng, Zihan; Qi, Chen-Feng; Si, Chuanping; He, John Cijiang; Liu, Kebin; Lira, Sergio A; Sikora, Andrew G; Li, Liwu; Xiong, Huabao

    2015-03-27

    Here we show that iNOS-deficient mice display enhanced classically activated M1 macrophage polarization without major effects on alternatively activated M2 macrophages. eNOS and nNOS mutant mice show comparable M1 macrophage polarization compared with wild-type control mice. Addition of N6-(1-iminoethyl)-L-lysine dihydrochloride, an iNOS inhibitor, significantly enhances M1 macrophage polarization while S-nitroso-N-acetylpenicillamine, a NO donor, suppresses M1 macrophage polarization. NO derived from iNOS mediates nitration of tyrosine residues in IRF5 protein, leading to the suppression of IRF5-targeted M1 macrophage signature gene activation. Computational analyses corroborate a circuit that fine-tunes the expression of IL-12 by iNOS in macrophages, potentially enabling versatile responses based on changing microenvironments. Finally, studies of an experimental model of endotoxin shock show that iNOS deficiency results in more severe inflammation with an enhanced M1 macrophage activation phenotype. These results suggest that NO derived from iNOS in activated macrophages suppresses M1 macrophage polarization.

  4. Novel Markers to Delineate Murine M1 and M2 Macrophages

    PubMed Central

    Jablonski, Kyle A.; Amici, Stephanie A.; Webb, Lindsay M.; Ruiz-Rosado, Juan de Dios; Popovich, Phillip G.; Partida-Sanchez, Santiago; Guerau-de-Arellano, Mireia

    2015-01-01

    Classically (M1) and alternatively activated (M2) macrophages exhibit distinct phenotypes and functions. It has been difficult to dissect macrophage phenotypes in vivo, where a spectrum of macrophage phenotypes exists, and also in vitro, where low or non-selective M2 marker protein expression is observed. To provide a foundation for the complexity of in vivo macrophage phenotypes, we performed a comprehensive analysis of the transcriptional signature of murine M0, M1 and M2 macrophages and identified genes common or exclusive to either subset. We validated by real-time PCR an M1-exclusive pattern of expression for CD38, G-protein coupled receptor 18 (Gpr18) and Formyl peptide receptor 2 (Fpr2) whereas Early growth response protein 2 (Egr2) and c-Myc were M2-exclusive. We further confirmed these data by flow cytometry and show that M1 and M2 macrophages can be distinguished by their relative expression of CD38 and Egr2. Egr2 labeled more M2 macrophages (~70%) than the canonical M2 macrophage marker Arginase-1, which labels 24% of M2 macrophages. Conversely, CD38 labeled most (71%) in vitro M1 macrophages. In vivo, a similar CD38+ population greatly increased after LPS exposure. Overall, this work defines exclusive and common M1 and M2 signatures and provides novel and improved tools to distinguish M1 and M2 murine macrophages. PMID:26699615

  5. M1-like Macrophage Polarization Promotes Orthodontic Tooth Movement.

    PubMed

    He, D; Kou, X; Yang, R; Liu, D; Wang, X; Luo, Q; Song, Y; Liu, F; Yan, Y; Gan, Y; Zhou, Y

    2015-09-01

    Macrophages play a crucial role in inflammatory-mediated bone loss. Orthodontic tooth movement (OTM) is associated with inflammatory bone remodeling. However, whether and how macrophages contribute to mechanical force-induced OTM remains unknown. In this study, we hypothesized that polarization of M1-like macrophages may contribute to the OTM. Orthodontic nickel-titanium springs were applied to the upper first molars of rats or mice to induce OTM. The distance of OTM gradually increased after mechanical force was applied to the rats for 5 and 10 d. M1-like macrophage polarization and expression of M1 cytokine tumor necrosis factor (TNF)-α also increased after force application. More importantly, monocyte/macrophage depletion in mice by injection of clodronate liposomes decreased the distance of OTM and the number of tartrate-resistant acid phosphatase (TRAP)-positive osteoclasts and CD68(+) macrophages, accompanied by reduced expressions of M1 markers TNF-α and inducible nitric oxide synthase (iNOS), whereas systemic transfusion of M1 macrophages in mice increased them. Further experiments showed that injection of recombinant TNF-α increased the distance of OTM and the number of TRAP-positive osteoclasts and CD68(+) macrophages, as well as upregulated the expression of TNF-α and iNOS. Blockage of TNF-α by etanercept injection reduced the distance of OTM and the number of TRAP-positive osteoclasts and CD68(+) macrophages, as well as decreased the levels of TNF-α and iNOS. These data suggest that M1-like macrophage polarization promotes alveolar bone resorption and consequent OTM after mechanical force application.

  6. Anatomy of a Discovery: M1 and M2 Macrophages

    PubMed Central

    Mills, Charles Dudley

    2015-01-01

    M1 and M2 macrophage-type responses kill or repair in vivo. The unique ability of macrophages to make these polar opposite type of responses provides primary host protection and maintains tissue homeostasis throughout the animal kingdom. In humans and other higher animals, M1 and M2-type macrophage responses also initiate and direct T cells/adaptive immunity to provide additional protection such as Th1 (cytotoxic) or Th2 (antibody-mediated) type responses. Hence, macrophages were renamed M1 and M2 to indicate the central role of macrophages/innate immunity in immune systems. These findings indicate that the long held notion that adaptive immunity controls innate immunity was backward: a sea change in understanding how immune responses occur. The clinical impact of M1/kill and M2/repair responses is immense playing pivotal roles in curing (or causing) many diseases including infections, cancer, autoimmunity, and atherosclerosis. How M1/M2 came to be is an interesting story that, like life, involved Direction, Determination, Discouragement, and Discovery. PMID:25999950

  7. Salmonella typhimurium-induced M1 macrophage polarization is dependent on the bacterial O antigen.

    PubMed

    Luo, Fengling; Sun, Xiaoming; Qu, Zhen; Zhang, Xiaolian

    2016-02-01

    Recently, macrophages were shown to be capable of differentiating toward two phenotypes after antigen stimulation: a classically activated (M1) or an alternatively activated phenotype (M2). To investigate the effect of Salmonella enteric serovar typhimurium (S. typhimurium) on macrophage differentiation, we compared macrophage phenotypes after infection of murine bone marrow-derived macrophages with wild-type S. typhimurium and its isogenic rfc mutant. S. typhimurium C5 induced M1 macrophage polarization and enhanced inducible nitric oxide synthase expression by macrophages; this induction was dependent on Toll-like receptor 4. In contrast, the Δrfc mutant (S. typhimurium C5 rfc::Km(r)) lost this function and induced an M2 response in the macrophages. Here, we propose that S. typhimurium C5 is capable of polarizing macrophages towards the M1 phenotype and that this polarization is dependent on the O antigen encoded by rfc. Our finding indicates that M1 macrophage polarization induced by S. typhimurium may be related to the ability of this intracellular bacterium to survive and replicate within macrophages, which is essential for systemic disease.

  8. Molecular Mechanisms That Influence the Macrophage M1–M2 Polarization Balance

    PubMed Central

    Wang, Nan; Liang, Hongwei; Zen, Ke

    2014-01-01

    As an essential component of innate immunity, macrophages have multiple functions in both inhibiting or promoting cell proliferation and tissue repair. Diversity and plasticity are hallmarks of macrophages. Classical M1 and alternative M2 activation of macrophages, mirroring the Th1–Th2 polarization of T cells, represent two extremes of a dynamic changing state of macrophage activation. M1-type macrophages release cytokines that inhibit the proliferation of surrounding cells and damage contiguous tissue, and M2-type macrophages release cytokines that promote the proliferation of contiguous cells and tissue repair. M1–M2 polarization of macrophage is a tightly controlled process entailing a set of signaling pathways, transcriptional and posttranscriptional regulatory networks. An imbalance of macrophage M1–M2 polarization is often associated with various diseases or inflammatory conditions. Therefore, identification of the molecules associated with the dynamic changes of macrophage polarization and understanding their interactions is crucial for elucidating the molecular basis of disease progression and designing novel macrophage-mediated therapeutic strategies. PMID:25506346

  9. Much More than M1 and M2 Macrophages, There are also CD169+ and TCR+ Macrophages

    PubMed Central

    Chávez-Galán, Leslie; Olleros, Maria L.; Vesin, Dominique; Garcia, Irene

    2015-01-01

    Monocytes are considered to be precursor cells of the mononuclear phagocytic system, and macrophages are one of the leading members of this cellular system. Macrophages play highly diverse roles in maintaining an organism’s integrity by either directly participating in pathogen elimination or repairing tissue under sterile inflammatory conditions. There are different subpopulations of macrophages and each one has its own characteristics and functions. In this review, we summarize present knowledge on the polarization of macrophages that allows the generation of subpopulations called classically activated macrophages or M1 and alternative activated macrophages or M2. Furthermore, there are macrophages that their origin and characterization still remain unclear but have been involved as main players in some human pathologies. Thus, we also review three other categories of macrophages: tumor-associated macrophages, CD169+ macrophages, and the recently named TCR+ macrophages. Based on the literature, we provide information on the molecular characterization of these macrophage subpopulations and their specific involvement in several human pathologies such as cancer, infectious diseases, obesity, and asthma. The refined characterization of the macrophage subpopulations can be useful in designing new strategies, supplementing those already established for the treatment of diseases using macrophages as a therapeutic target. PMID:26074923

  10. M1 and M2 Macrophages: The Chicken and the Egg of Immunity

    PubMed Central

    Mills, Charles D.; Ley, Klaus

    2015-01-01

    The purpose of this perspective is to describe a critical advance in understanding how immune responses work. Macrophages are required for all animal life: ‘Inhibit’ type macrophages in all animals (called M1) can rapidly kill pathogens, and are thus the primary host defense, and ‘Heal’ type macrophages (M2) routinely repair and maintain tissue integrity. Macrophages perform these activities in all animals without T cells, and also in T cell-deficient vertebrates. Although adaptive immunity can amplify macrophage polarization, the long-held notion that macrophages need to be ‘activated’ or ‘alternatively activated’ by T cells is incorrect; indeed, immunology has had it backward. M1/M2-type macrophages necessarily direct T cells toward Th1- or Th2-like activities, respectively. That such macrophage-innate activities are the central directing element in immune responses is a dramatic change in understanding how immune systems operate. Most important, this revelation is opening up whole new approaches to immunotherapy. For example, many modern diseases, such as cancer and atherosclerosis, may not display ‘foreign’ antigens. However, there are clear imbalances in M1/M2-type responses. Correcting such innate imbalances can result in better health. Macrophages are the chicken and the egg of immunity. PMID:25138714

  11. β-Adrenergic-stimulated macrophages: Comprehensive localization in the M1-M2 spectrum.

    PubMed

    Lamkin, Donald M; Ho, Hsin-Yun; Ong, Tiffany H; Kawanishi, Carly K; Stoffers, Victoria L; Ahlawat, Nivedita; Ma, Jeffrey C Y; Arevalo, Jesusa M G; Cole, Steve W; Sloan, Erica K

    2016-10-01

    β-Adrenergic signaling can regulate macrophage involvement in several diseases and often produces anti-inflammatory properties in macrophages, which are similar to M2 properties in a dichotomous M1 vs. M2 macrophage taxonomy. However, it is not clear that β-adrenergic-stimulated macrophages may be classified strictly as M2. In this in vitro study, we utilized recently published criteria and transcriptome-wide bioinformatics methods to map the relative polarity of murine β-adrenergic-stimulated macrophages within a wider M1-M2 spectrum. Results show that β-adrenergic-stimulated macrophages did not fit entirely into any one pre-defined category of the M1-M2 spectrum but did express genes that are representative of some M2 side categories. Moreover, transcript origin analysis of genome-wide transcriptional profiles located β-adrenergic-stimulated macrophages firmly on the M2 side of the M1-M2 spectrum and found active suppression of M1 side gene transcripts. The signal transduction pathways involved were mapped through blocking experiments and bioinformatics analysis of transcription factor binding motifs. M2-promoting effects were mediated specifically through β2-adrenergic receptors and were associated with CREB, C/EBPβ, and ATF transcription factor pathways but not with established M1-M2 STAT pathways. Thus, β-adrenergic-signaling induces a macrophage transcriptome that locates on the M2 side of the M1-M2 spectrum but likely accomplishes this effect through a signaling pathway that is atypical for M2-spectrum macrophages. PMID:27485040

  12. Aurora kinase a regulates m1 macrophage polarization and plays a role in experimental autoimmune encephalomyelitis.

    PubMed

    Ding, Lixia; Gu, Haijuan; Gao, Xiaoming; Xiong, Sidong; Zheng, Biao

    2015-04-01

    Macrophage polarization is a dynamic and integral process of tissue inflammation and remodeling. Here we demonstrate an important role of Aurora kinase A in the regulation of inflammatory M1 macrophage polarization. We found that there was an elevated expression of Aurora-A in M1 macrophages and inhibition of Aurora-A by small molecules or specific siRNA selectively led to the suppression of M1 polarization, sparing over the M2 macrophage differentiation. At the molecular level, we found that the effects of Aurora-A in M1 macrophages were mediated through the down-regulation of NF-κB pathway and subsequent IRF5 expression. In an autoimmune disease model, experimental autoimmune encephalitis (EAE), treatment with Aurora kinase inhibitor blocked the disease development and shifted the macrophage phenotype from inflammatory M1 to anti-inflammatory M2. Thus, this study reveals a novel function of Aurora-A in controlling the polarization of macrophages, and modification of Aurora-A activity may lead to a new therapeutic approach for chronic inflammatory diseases.

  13. Yeast (Saccharomyces cerevisiae) Polarizes Both M-CSF- and GM-CSF-Differentiated Macrophages Toward an M1-Like Phenotype.

    PubMed

    Seif, Michelle; Philippi, Anja; Breinig, Frank; Kiemer, Alexandra K; Hoppstädter, Jessica

    2016-10-01

    Macrophages are a heterogeneous and plastic cell population with two main phenotypes: pro-inflammatory classically activated macrophages (M1) and anti-inflammatory alternatively activated macrophages (M2). Saccharomyces cerevisiae is a promising vehicle for the delivery of vaccines. It is well established that S. cerevisiae is taken up by professional phagocytic cells. However, the response of human macrophages to S. cerevisiae is ill-defined. In this study, we characterized the interaction between S. cerevisiae and M1- or M2-like macrophages. M1-like macrophages had a higher yeast uptake capacity than M2-like macrophages, but both cell types internalized opsonized yeast to the same extent. The M1 surface markers HLAII and CD86 were upregulated after yeast uptake in M1- and M2-like macrophages. Moreover, mRNA expression levels of pro-inflammatory cytokines, such as TNF-α, IL-12, and IL-6, increased, whereas the expression of anti-inflammatory mediators did not change. These results demonstrate that S. cerevisiae can target both M1 and M2 macrophages, paralleled by skewing toward an M1 phenotype. Thus, the use of yeast-based delivery systems might be a promising approach for the treatment of pathologic conditions that would benefit from the presence of M1-polarized macrophages, such as cancer.

  14. Enhanced M1/M2 macrophage ratio promotes orthodontic root resorption.

    PubMed

    He, D; Kou, X; Luo, Q; Yang, R; Liu, D; Wang, X; Song, Y; Cao, H; Zeng, M; Gan, Y; Zhou, Y

    2015-01-01

    Mechanical force-induced orthodontic root resorption is a major clinical challenge in orthodontic treatment. Macrophages play an important role in orthodontic root resorption, but the underlying mechanism remains unclear. In this study, we examined the mechanism by which the ratio of M1 to M2 macrophage polarization affects root resorption during orthodontic tooth movement. Root resorption occurred when nickel-titanium coil springs were applied on the upper first molars of rats for 3 to 14 d. Positively stained odontoclasts or osteoclasts with tartrate-resistant acid phosphatase were found in resorption areas. Meanwhile, M1-like macrophages positive for CD68 and inducible nitric oxide synthase (iNOS) persistently accumulated on the compression side of periodontal tissues. In addition, the expressions of the M1 activator interferon-γ and the M1-associated pro-inflammatory cytokine tumor necrosis factor (TNF)-α were upregulated on the compression side of periodontal tissues. When the coil springs were removed at the 14th day after orthodontic force application, root resorption was partially rescued. The number of CD68(+)CD163(+) M2-like macrophages gradually increased on the compression side of periodontal tissues. The levels of M2 activator interleukin (IL)-4 and the M2-associated anti-inflammatory cytokine IL-10 also increased. Systemic injection of the TNF-α inhibitor etanercept or IL-4 attenuated the severity of root resorption and decreased the ratio of M1 to M2 macrophages. These data imply that the balance between M1 and M2 macrophages affects orthodontic root resorption. Root resorption was aggravated by an enhanced M1/M2 ratio but was partially rescued by a reduced M1/M2 ratio.

  15. Rac2 Controls Tumor Growth, Metastasis and M1-M2 Macrophage Differentiation In Vivo

    PubMed Central

    Joshi, Shweta; Singh, Alok R.; Zulcic, Muamera; Bao, Lei; Messer, Karen; Ideker, Trey; Dutkowski, Janusz; Durden, Donald L.

    2014-01-01

    Although it is well-established that the macrophage M1 to M2 transition plays a role in tumor progression, the molecular basis for this process remains incompletely understood. Herein, we demonstrate that the small GTPase, Rac2 controls macrophage M1 to M2 differentiation and the metastatic phenotype in vivo. Using a genetic approach, combined with syngeneic and orthotopic tumor models we demonstrate that Rac2-/- mice display a marked defect in tumor growth, angiogenesis and metastasis. Microarray, RT-PCR and metabolomic analysis on bone marrow derived macrophages isolated from the Rac2-/- mice identify an important role for Rac2 in M2 macrophage differentiation. Furthermore, we define a novel molecular mechanism by which signals transmitted from the extracellular matrix via the α4β1 integrin and MCSF receptor lead to the activation of Rac2 and potentially regulate macrophage M2 differentiation. Collectively, our findings demonstrate a macrophage autonomous process by which the Rac2 GTPase is activated downstream of the α4β1 integrin and the MCSF receptor to control tumor growth, metastasis and macrophage differentiation into the M2 phenotype. Finally, using gene expression and metabolomic data from our Rac2-/- model, and information related to M1-M2 macrophage differentiation curated from the literature we executed a systems biologic analysis of hierarchical protein-protein interaction networks in an effort to develop an iterative interactome map which will predict additional mechanisms by which Rac2 may coordinately control macrophage M1 to M2 differentiation and metastasis. PMID:24770346

  16. Aldosterone Induces Renal Fibrosis and Inflammatory M1-Macrophage Subtype via Mineralocorticoid Receptor in Rats

    PubMed Central

    Martín-Fernández, Beatriz; Rubio-Navarro, Alfonso; Cortegano, Isabel; Ballesteros, Sandra; Alía, Mario; Cannata-Ortiz, Pablo; Olivares-Álvaro, Elena; Egido, Jesús; de Andrés, Belén; Gaspar, María Luisa; de las Heras, Natalia; Lahera, Vicente; Moreno, Juan Antonio

    2016-01-01

    We aimed to evaluate macrophages heterogeneity and structural, functional and inflammatory alterations in rat kidney by aldosterone + salt administration. The effects of treatment with spironolactone on above parameters were also analyzed. Male Wistar rats received aldosterone (1 mgkg-1d-1) + 1% NaCl for 3 weeks. Half of the animals were treated with spironolactone (200 mg kg-1d-1). Systolic and diastolic blood pressures were elevated (p<0.05) in aldosterone + salt–treated rats. Relative kidney weight, collagen content, fibronectin, macrophage infiltrate, CTGF, Col I, MMP2, TNF-α, CD68, Arg2, and SGK-1 were increased (p<0.05) in aldosterone + salt–treated rats, being reduced by spironolactone (p<0.05). Increased iNOS and IFN-γ mRNA gene expression (M1 macrophage markers) was observed in aldosterone + salt rats, whereas no significant differences were observed in IL-10 and gene ArgI mRNA expression or ED2 protein content (M2 macrophage markers). All the observed changes were blocked with spironolactone treatment. Macrophage depletion with liposomal clodronate reduced macrophage influx and inflammatory M1 markers (INF-γ or iNOS), whereas interstitial fibrosis was only partially reduced after this intervention, in aldosterone plus salt-treated rats. In conclusion, aldosterone + salt administration mediates inflammatory M1 macrophage phenotype and increased fibrosis throughout mineralocorticoid receptors activation. PMID:26730742

  17. Anti-CD47 Treatment Stimulates Phagocytosis of Glioblastoma by M1 and M2 Polarized Macrophages and Promotes M1 Polarized Macrophages In Vivo

    PubMed Central

    Kahn, Suzana A.; Azad, Tej D.; Gholamin, Sharareh; Xu, Chelsea Y.; Liu, Jie; Achrol, Achal S.; Richard, Chase; Sommerkamp, Pia; Schoen, Matthew Kenneth; McCracken, Melissa N.; Majeti, Ravi; Weissman, Irving; Mitra, Siddhartha S.; Cheshier, Samuel H.

    2016-01-01

    Tumor-associated macrophages (TAMs) represent an important cellular subset within the glioblastoma (WHO grade IV) microenvironment and are a potential therapeutic target. TAMs display a continuum of different polarization states between antitumorigenic M1 and protumorigenic M2 phenotypes, with a lower M1/M2 ratio correlating with worse prognosis. Here, we investigated the effect of macrophage polarization on anti-CD47 antibody-mediated phagocytosis of human glioblastoma cells in vitro, as well as the effect of anti-CD47 on the distribution of M1 versus M2 macrophages within human glioblastoma cells grown in mouse xenografts. Bone marrow-derived mouse macrophages and peripheral blood-derived human macrophages were polarized in vitro toward M1 or M2 phenotypes and verified by flow cytometry. Primary human glioblastoma cell lines were offered as targets to mouse and human M1 or M2 polarized macrophages in vitro. The addition of an anti-CD47 monoclonal antibody led to enhanced tumor-cell phagocytosis by mouse and human M1 and M2 macrophages. In both cases, the anti-CD47-induced phagocytosis by M1 was more prominent than that for M2. Dissected tumors from human glioblastoma xenografted within NOD.Cg-Prkdcscid Il2rgtm1Wjl/SzJ mice and treated with anti-CD47 showed a significant increase of M1 macrophages within the tumor. These data show that anti-CD47 treatment leads to enhanced tumor cell phagocytosis by both M1 and M2 macrophage subtypes with a higher phagocytosis rate by M1 macrophages. Furthermore, these data demonstrate that anti-CD47 treatment alone can shift the phenotype of macrophages toward the M1 subtype in vivo. PMID:27092773

  18. Anti-CD47 Treatment Stimulates Phagocytosis of Glioblastoma by M1 and M2 Polarized Macrophages and Promotes M1 Polarized Macrophages In Vivo.

    PubMed

    Zhang, Michael; Hutter, Gregor; Kahn, Suzana A; Azad, Tej D; Gholamin, Sharareh; Xu, Chelsea Y; Liu, Jie; Achrol, Achal S; Richard, Chase; Sommerkamp, Pia; Schoen, Matthew Kenneth; McCracken, Melissa N; Majeti, Ravi; Weissman, Irving; Mitra, Siddhartha S; Cheshier, Samuel H

    2016-01-01

    Tumor-associated macrophages (TAMs) represent an important cellular subset within the glioblastoma (WHO grade IV) microenvironment and are a potential therapeutic target. TAMs display a continuum of different polarization states between antitumorigenic M1 and protumorigenic M2 phenotypes, with a lower M1/M2 ratio correlating with worse prognosis. Here, we investigated the effect of macrophage polarization on anti-CD47 antibody-mediated phagocytosis of human glioblastoma cells in vitro, as well as the effect of anti-CD47 on the distribution of M1 versus M2 macrophages within human glioblastoma cells grown in mouse xenografts. Bone marrow-derived mouse macrophages and peripheral blood-derived human macrophages were polarized in vitro toward M1 or M2 phenotypes and verified by flow cytometry. Primary human glioblastoma cell lines were offered as targets to mouse and human M1 or M2 polarized macrophages in vitro. The addition of an anti-CD47 monoclonal antibody led to enhanced tumor-cell phagocytosis by mouse and human M1 and M2 macrophages. In both cases, the anti-CD47-induced phagocytosis by M1 was more prominent than that for M2. Dissected tumors from human glioblastoma xenografted within NOD.Cg-Prkdcscid Il2rgtm1Wjl/SzJ mice and treated with anti-CD47 showed a significant increase of M1 macrophages within the tumor. These data show that anti-CD47 treatment leads to enhanced tumor cell phagocytosis by both M1 and M2 macrophage subtypes with a higher phagocytosis rate by M1 macrophages. Furthermore, these data demonstrate that anti-CD47 treatment alone can shift the phenotype of macrophages toward the M1 subtype in vivo.

  19. Rabbit M1 and M2 macrophages can be induced by human recombinant GM-CSF and M-CSF.

    PubMed

    Yamane, Kazuyoshi; Leung, Kai-Poon

    2016-09-01

    Macrophages can change their phenotype in response to environmental cues. Polarized macrophages are broadly classified into two groups: classical activated M1 and alternative activated M2. Characterization of human macrophages has been widely studied, but polarized macrophages in rabbits have not been characterized. We characterized rabbit macrophages that were polarized using human recombinant GM-CSF and M-CSF. GM-CSF-treated macrophages had higher mRNA expression of proinflammatory cytokines (M1 phenotype) than did the M-CSF-treated counterpart. By contrast, high levels of TGF-β and IL-10 expression (M2 phenotype) were found in M-CSF-treated macrophages. The present study may be useful to understand roles of polarized macrophages in rabbit disease models. PMID:27642558

  20. An M1-like Macrophage Polarization in Decidual Tissue during Spontaneous Preterm Labor That Is Attenuated by Rosiglitazone Treatment.

    PubMed

    Xu, Yi; Romero, Roberto; Miller, Derek; Kadam, Leena; Mial, Tara N; Plazyo, Olesya; Garcia-Flores, Valeria; Hassan, Sonia S; Xu, Zhonghui; Tarca, Adi L; Drewlo, Sascha; Gomez-Lopez, Nardhy

    2016-03-15

    Decidual macrophages are implicated in the local inflammatory response that accompanies spontaneous preterm labor/birth; however, their role is poorly understood. We hypothesized that decidual macrophages undergo a proinflammatory (M1) polarization during spontaneous preterm labor and that PPARγ activation via rosiglitazone (RSG) would attenuate the macrophage-mediated inflammatory response, preventing preterm birth. In this study, we show that: 1) decidual macrophages undergo an M1-like polarization during spontaneous term and preterm labor; 2) anti-inflammatory (M2)-like macrophages are more abundant than M1-like macrophages in decidual tissue; 3) decidual M2-like macrophages are reduced in preterm pregnancies compared with term pregnancies, regardless of the presence of labor; 4) decidual macrophages express high levels of TNF and IL-12 but low levels of peroxisome proliferator-activated receptor γ (PPARγ) during spontaneous preterm labor; 5) decidual macrophages from women who underwent spontaneous preterm labor display plasticity by M1↔M2 polarization in vitro; 6) incubation with RSG reduces the expression of TNF and IL-12 in decidual macrophages from women who underwent spontaneous preterm labor; and 7) treatment with RSG reduces the rate of LPS-induced preterm birth and improves neonatal outcomes by reducing the systemic proinflammatory response and downregulating mRNA and protein expression of NF-κB, TNF, and IL-10 in decidual and myometrial macrophages in C57BL/6J mice. In summary, we demonstrated that decidual M1-like macrophages are associated with spontaneous preterm labor and that PPARγ activation via RSG can attenuate the macrophage-mediated proinflammatory response, preventing preterm birth and improving neonatal outcomes. These findings suggest that the PPARγ pathway is a new molecular target for future preventative strategies for spontaneous preterm labor/birth.

  1. Paracoccin Induces M1 Polarization of Macrophages via Interaction with TLR4.

    PubMed

    Freitas, Mateus S; Oliveira, Aline F; da Silva, Thiago A; Fernandes, Fabrício F; Gonçales, Relber A; Almeida, Fausto; Roque-Barreira, Maria C

    2016-01-01

    The fungal human pathogen Paracoccidioides brasiliensis contains paracoccin (PCN), a multi-domain protein that has lectin and N-acetyl-glucosaminidase activities, which account for its effects on the growth and morphogenesis of the fungus and on the activation of host macrophages through its interaction with TLR N-glycans. With the purpose of detailing the knowledge on the effects of PCN on macrophages, we used recombinant PCN expressed in Pichia pastoris (p-rPCN) to stimulate isolated murine peritoneal macrophages. The activation of these cells manifested through the release of high levels of inflammatory mediators, such as nitric oxide, TNF-α, IL-12p40, and IL-6. Furthermore, peritoneal macrophages stimulated with p-rPCN increased the relative expression of STAT1, SOCS3, and iNOS2 mRNA (M1 polarization markers). However, the expression of Arginase-1, Ym-1, and FIZZ1 (M2 polarization markers) remained at basal levels. Interestingly, the observed M1 macrophages' polarization triggered by p-rPCN was abolished in cells obtained from knockout Toll-like receptor-4 mice. In this case, the p-rPCN-induced production of pro-inflammatory mediators was blocked too. These results demonstrate that the classical activation of macrophages induced by paracoccin depends on TLR4. Taken together, the results of our study indicate that paracoccin acts as a TLR agonist able to modulate immunity and exerts biological activities that favor its applicability as an immunotherapeutic agent to combat systemic fungal infections. PMID:27458431

  2. Opposite Effects of M1 and M2 Macrophage Subtypes on Lung Cancer Progression

    PubMed Central

    Yuan, Ang; Hsiao, Yi-Jing; Chen, Hsuan-Yu; Chen, Huei-Wen; Ho, Chao-Chi; Chen, Yu-Yun; Liu, Yi-Chia; Hong, Tsai-Hsia; Yu, Sung-Liang; Chen, Jeremy J.W.; Yang, Pan-Chyr

    2015-01-01

    Macrophages in a tumor microenvironment have been characterized as M1- and M2-polarized subtypes. Here, we discovered the different macrophages’ impacts on lung cancer cell A549. The M2a/M2c subtypes promoted A549 invasion and xenograft tumor growth. The M1 subtype suppressed angiogenesis. M1 enhanced the sensitivity of A549 to cisplatin and decreased the tube formation activity and cell viability of A549 cells by inducing apoptosis and senescence. Different macrophage subtypes regulated genes involved in the immune response, cytoskeletal remodeling, coagulation, cell adhesion, and apoptosis pathways in A549 cells, which was a pattern that correlated with the altered behaviors of the A549 cells. Furthermore, we found that the identified M1/M2 gene signatures were significantly correlated with the extended overall survival of lung cancer patients. These results suggest that M1/M2 gene expression signature may be used as a prognostic indicator for lung cancer patients, and M1/M2 polarization may be a target of investigation of immune-modulating therapies for lung cancer in the future. PMID:26399191

  3. Elastin-Derived Peptides Promote Abdominal Aortic Aneurysm Formation by Modulating M1/M2 Macrophage Polarization.

    PubMed

    Dale, Matthew A; Xiong, Wanfen; Carson, Jeffrey S; Suh, Melissa K; Karpisek, Andrew D; Meisinger, Trevor M; Casale, George P; Baxter, B Timothy

    2016-06-01

    Abdominal aortic aneurysm is a dynamic vascular disease characterized by inflammatory cell invasion and extracellular matrix degradation. Damage to elastin in the extracellular matrix results in release of elastin-derived peptides (EDPs), which are chemotactic for inflammatory cells such as monocytes. Their effect on macrophage polarization is less well known. Proinflammatory M1 macrophages initially are recruited to sites of injury, but, if their effects are prolonged, they can lead to chronic inflammation that prevents normal tissue repair. Conversely, anti-inflammatory M2 macrophages reduce inflammation and aid in wound healing. Thus, a proper M1/M2 ratio is vital for tissue homeostasis. Abdominal aortic aneurysm tissue reveals a high M1/M2 ratio in which proinflammatory cells and their associated markers dominate. In the current study, in vitro treatment of bone marrow-derived macrophages with EDPs induced M1 macrophage polarization. By using C57BL/6 mice, Ab-mediated neutralization of EDPs reduced aortic dilation, matrix metalloproteinase activity, and proinflammatory cytokine expression at early and late time points after aneurysm induction. Furthermore, direct manipulation of the M1/M2 balance altered aortic dilation. Injection of M2-polarized macrophages reduced aortic dilation after aneurysm induction. EDPs promoted a proinflammatory environment in aortic tissue by inducing M1 polarization, and neutralization of EDPs attenuated aortic dilation. The M1/M2 imbalance is vital to aneurysm formation. PMID:27183603

  4. Paracoccin Induces M1 Polarization of Macrophages via Interaction with TLR4

    PubMed Central

    Freitas, Mateus S.; Oliveira, Aline F.; da Silva, Thiago A.; Fernandes, Fabrício F.; Gonçales, Relber A.; Almeida, Fausto; Roque-Barreira, Maria C.

    2016-01-01

    The fungal human pathogen Paracoccidioides brasiliensis contains paracoccin (PCN), a multi-domain protein that has lectin and N-acetyl-glucosaminidase activities, which account for its effects on the growth and morphogenesis of the fungus and on the activation of host macrophages through its interaction with TLR N-glycans. With the purpose of detailing the knowledge on the effects of PCN on macrophages, we used recombinant PCN expressed in Pichia pastoris (p-rPCN) to stimulate isolated murine peritoneal macrophages. The activation of these cells manifested through the release of high levels of inflammatory mediators, such as nitric oxide, TNF-α, IL-12p40, and IL-6. Furthermore, peritoneal macrophages stimulated with p-rPCN increased the relative expression of STAT1, SOCS3, and iNOS2 mRNA (M1 polarization markers). However, the expression of Arginase-1, Ym-1, and FIZZ1 (M2 polarization markers) remained at basal levels. Interestingly, the observed M1 macrophages’ polarization triggered by p-rPCN was abolished in cells obtained from knockout Toll-like receptor-4 mice. In this case, the p-rPCN-induced production of pro-inflammatory mediators was blocked too. These results demonstrate that the classical activation of macrophages induced by paracoccin depends on TLR4. Taken together, the results of our study indicate that paracoccin acts as a TLR agonist able to modulate immunity and exerts biological activities that favor its applicability as an immunotherapeutic agent to combat systemic fungal infections. PMID:27458431

  5. The MSHA strain of Pseudomonas aeruginosa (PA-MSHA) inhibits gastric carcinoma progression by inducing M1 macrophage polarization.

    PubMed

    Wang, Changming; Hu, Zunqi; Zhu, Zhenxin; Zhang, Xin; Wei, Ziran; Zhang, Yu; Hu, Dali; Cai, Qingping

    2016-05-01

    Macrophages play crucial roles in promoting tumor development and progression. In the present study, we found that the mannose-sensitive hemagglutination pilus strain of Pseudomonas aeruginosa (PA-MSHA) was efficient in inducing M1 macrophage polarization. PA-MSHA treatment increases expression of M1-related cytokines and promotes activation of murine peritoneal macrophages (MPM). Interestingly, PA-MSHA inhibits cell proliferation and migration and induces the apoptosis of gastric carcinoma cells. These effects of PA-MSHA on M1 polarization were associated with activation of NF-κB expression. Thus, inducing polarization of M1 by PA-MSHA may be one potential strategy for inhibiting gastric carcinoma progression in mice.

  6. Differences in forward angular light scattering distributions between M1 and M2 macrophages

    NASA Astrophysics Data System (ADS)

    Halaney, David L.; Zahedivash, Aydin; Phipps, Jennifer E.; Wang, Tianyi; Dwelle, Jordan; Saux, Claude Jourdan Le; Asmis, Reto; Milner, Thomas E.; Feldman, Marc D.

    2015-11-01

    The ability to distinguish macrophage subtypes noninvasively could have diagnostic potential in cancer, atherosclerosis, and diabetes, where polarized M1 and M2 macrophages play critical and often opposing roles. Current methods to distinguish macrophage subtypes rely on tissue biopsy. Optical imaging techniques based on light scattering are of interest as they can be translated into biopsy-free strategies. Because mitochondria are relatively strong subcellular light scattering centers, and M2 macrophages are known to have enhanced mitochondrial biogenesis compared to M1, we hypothesized that M1 and M2 macrophages may have different angular light scattering profiles. To test this, we developed an in vitro angle-resolved forward light scattering measurement system. We found that M1 and M2 macrophage monolayers scatter relatively unequal amounts of light in the forward direction between 1.6 deg and 3.2 deg with M2 forward scattering significantly more light than M1 at increasing angles. The ratio of forward scattering can be used to identify the polarization state of macrophage populations in culture.

  7. Differences in forward angular light scattering distributions between M1 and M2 macrophages.

    PubMed

    Halaney, David L; Zahedivash, Aydin; Phipps, Jennifer E; Wang, Tianyi; Dwelle, Jordan; Saux, Claude Jourdan Le; Asmis, Reto; Milner, Thomas E; Feldman, Marc D

    2015-11-01

    The ability to distinguish macrophage subtypes noninvasively could have diagnostic potential in cancer, atherosclerosis, and diabetes, where polarized M1 and M2 macrophages play critical and often opposing roles. Current methods to distinguish macrophage subtypes rely on tissue biopsy. Optical imaging techniques based on light scattering are of interest as they can be translated into biopsy-free strategies. Because mitochondria are relatively strong subcellular light scattering centers, and M2 macrophages are known to have enhanced mitochondrial biogenesis compared to M1, we hypothesized that M1 and M2 macrophages may have different angular light scattering profiles. To test this, we developed an in vitro angle-resolved forward light scattering measurement system. We found that M1 and M2 macrophage monolayers scatter relatively unequal amounts of light in the forward direction between 1.6 deg and 3.2 deg with M2 forward scattering significantly more light than M1 at increasing angles. The ratio of forward scattering can be used to identify the polarization state of macrophage populations in culture. PMID:26538329

  8. Augmented macrophage differentiation and polarization of tumor-associated macrophages towards M1 subtype in listeria-administered tumor-bearing host.

    PubMed

    Rai, Rakesh K; Vishvakarma, Naveen K; Mohapatra, Tribhuban M; Singh, Sukh Mahendra

    2012-09-01

    This study investigates the effect of Listeria administration on differentiation of macrophages from precursor bone marrow cells and functional status of tumor-associated macrophages (TAM). Listeria administration not only resulted in an augmented infiltration of tumor by F4/80 macrophages but also repolarized the functional status of TAM displaying features of some M1 macrophage subtype with upregulated phagocytosis and tumoricidal activity accompanied by altered expression of monocarboxylate transporter-1, toll-like receptor-2, surface markers: CD11c, interleukin-2 receptor, CD62L, and secreted molecules: nitric oxide, interleukin (IL)-1, IL-6, tumor necrosis factor-α, and vascular endothelial growth factor. Declined tumor cell survival and modulated repertoire of cytokines: interferon-γ, IL-6, IL-10, and transforming growth factor-β in tumor microenvironment indicated their role in polarization of TAM towards proinflammatory state. Bone marrow cell of Listeria-administered tumor-bearing mice showed augmented survival, declined expression of p53 upregulated modulator of apoptosis with an upregulated differentiation into activation responsive bone marrow-derived macrophages along with altered expression of macrophage-colony stimulating factor, macrophage-colony stimulating factor receptor, and granulocyte macrophage-colony stimulating factor receptor. These findings indicate that Listeria infection is associated with an augmented differentiation of macrophages accompanied by tumoricidal activation of TAM.

  9. Tim-3 promotes intestinal homeostasis in DSS colitis by inhibiting M1 polarization of macrophages.

    PubMed

    Jiang, Xingwei; Yu, Jiahui; Shi, Qingzhu; Xiao, Yan; Wang, Wei; Chen, Guojiang; Zhao, Zhi; Wang, Renxi; Xiao, He; Hou, Chunmei; Feng, Jiannan; Ma, Yuanfang; Shen, Beifen; Wang, Lili; Li, Yan; Han, Gencheng

    2015-10-01

    Tim-3 is involved in the physiopathology of inflammatory bowel disease (IBD), but the underlying mechanism is unknown. Here, we demonstrated that, in mouse with DSS colitis, Tim-3 inhibited the polarization of pathogenic pro-inflammatory M1 macrophages, while Tim-3 downregulation or blockade resulted in an increased M1 response. Adoptive transfer of Tim-3-silenced macrophages worsened DSS colitis and enhanced inflammation, while Tim-3 overexpression attenuated DSS colitis by decreasing the M1 macrophage response. Co-culture of Tim-3-overexpressing macrophages with intestinal lymphocytes decreased the pro-inflammatory response. Tim-3 shaped intestinal macrophage polarization may be TLR-4 dependent since Tim-3 blockade failed to exacerbate colitis or increase M1 macrophage response in the TLR-4 KO model. Finally, Tim-3 signaling inhibited phosphorylation of IRF3, a TLR-4 downstream transcriptional factor regulating macrophage polarization. A better understanding of this pathway may shed new light on colitis pathogenesis and result in a new therapeutic strategy.

  10. Effects of IRF1 and IFN-β interaction on the M1 polarization of macrophages and its antitumor function

    PubMed Central

    XIE, CHANGLI; LIU, CUIYING; WU, BITAO; LIN, YAN; MA, TINGTING; XIONG, HAIYU; WANG, QIN; LI, ZIWEI; MA, CHENYU; TU, ZHIGUANG

    2016-01-01

    Macrophages that differentiate from precursor monocytes can be polarized into a classically activated (M1) or alternatively activated (M2) status depending on different stimuli. Generally, interferon (IFN)-γ and lipopolysaccharide (LPS) are considered the classical stimuli with which to establish M1 polarization. IFN regulatory factor (IRF)1 and IFN-β are two crucial molecules involved in IFN-γ- and LPS-initialed signaling. However, the association between IRF1 and IFN-β in the context of the M1 polarization of macrophages is not yet fully understood. In this study, we demonstrate that U937-derived macrophages, in response to IFN-γ and LPS stimulation, readily acquire an M1 status, indicated by the increased expression of interleukin (IL)-12, IL-6, IL-23, tumor necrosis factor (TNF)-α and the M1-specific cell surface antigen, CD86, and the decreased expression of the M2-specific mannose receptor, CD206. However, the knockdown of IRF1 in U937-derived macrophages led to an impaired M1 status, as indicated by the decreased expression of the above-mentioned M1 markers, and the increased expression of the M2 markers, CD206 and IL-10. A similar phenomenon was observed in the M1 macrophages in which IFN-β was inhibited. Furthermore, we demonstrated that IRF1 and IFN-β may interact with each other in the IFN-γ- and LPS-initiated signaling pathway, and contribute to the IRF5 regulation of M1 macrophages. In addition, the conditioned medium collected from the M1 macrophages in which IRF1 or IFN-β were inhibited, exerted pro-tumor effects on the HepG2 and SMMC-7721 cells, as indicated by an increase in proliferation, the inhibition of apoptosis and an enhanced invasion capability. The findings of our study suggest that the interactions of IRF1, IFN-β and IRF5 are involved in the M1 polarization of macro phages and have antitumor functions. These data may provide a novel antitumor strategy for targeted cancer therapy. PMID:27176664

  11. An unrestrained proinflammatory M1 macrophage population induced by iron impairs wound healing in humans and mice

    PubMed Central

    Sindrilaru, Anca; Peters, Thorsten; Wieschalka, Stefan; Baican, Corina; Baican, Adrian; Peter, Henriette; Hainzl, Adelheid; Schatz, Susanne; Qi, Yu; Schlecht, Andrea; Weiss, Johannes M.; Wlaschek, Meinhard; Sunderkötter, Cord; Scharffetter-Kochanek, Karin

    2011-01-01

    Uncontrolled macrophage activation is now considered to be a critical event in the pathogenesis of chronic inflammatory diseases such as atherosclerosis, multiple sclerosis, and chronic venous leg ulcers. However, it is still unclear which environmental cues induce persistent activation of macrophages in vivo and how macrophage-derived effector molecules maintain chronic inflammation and affect resident fibroblasts essential for tissue homeostasis and repair. We used a complementary approach studying human subjects with chronic venous leg ulcers, a model disease for macrophage-driven chronic inflammation, while establishing a mouse model closely reflecting its pathogenesis. Here, we have shown that iron overloading of macrophages — as was found to occur in human chronic venous leg ulcers and the mouse model — induced a macrophage population in situ with an unrestrained proinflammatory M1 activation state. Via enhanced TNF-α and hydroxyl radical release, this macrophage population perpetuated inflammation and induced a p16INK4a-dependent senescence program in resident fibroblasts, eventually leading to impaired wound healing. This study provides insight into the role of what we believe to be a previously undescribed iron-induced macrophage population in vivo. Targeting this population may hold promise for the development of novel therapies for chronic inflammatory diseases such as chronic venous leg ulcers. PMID:21317534

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

    PubMed

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

    2014-01-01

    Human T2D is characterized by a low-grade systemic inflammation, loss of β-cells, and diminished insulin production. Local islet immunity is still poorly understood, and hence, we evaluated macrophage subpopulations in pancreatic islets in the well-established murine model of T2D, the db/db mouse. Already at 8 weeks of disease, on average, 12 macrophages were observed in the diabetic islets, whereas only two were recorded in the nondiabetic littermates. On a detailed level, the islet resident macrophages increased fourfold compared with nondiabetic littermates, whereas a pronounced recruitment (eightfold) of a novel subset of macrophages (CD68+F4/80-) was observed. The majority of the CD68+F4/80+ but only 40% of the CD68+F4/80- islet macrophages expressed CD11b. Both islet-derived macrophage subsets expressed moderate MHC-II, high galectin-3, and low CD80/CD86 levels, suggesting the cells to be macrophages rather than DCs. On a functional level, the vast majority of the macrophages in the diabetic islets was of the proinflammatory, M1-like phenotype. The systemic immunity in diabetic animals was characterized by a low-grade inflammation with elevated cytokine levels and increase of splenic cytokine, producing CD68+F4/80- macrophages. In late-stage diabetes, the cytokine signature changed toward a TGF-β-dominated profile, coinciding with a significant increase of galectin-3-positive macrophages in the spleen. In summary, our results show that proinflammatory M1-like galectin-3+ CD80/CD86(low) macrophages invade diabetic islets. Moreover, the innate immunity matures in a diabetes-dependent manner from an initial proinflammatory toward a profibrotic phenotype, supporting the concept that T2D is an inflammatory disease. PMID:24009176

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

    PubMed

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

    2014-01-01

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

  14. Human monocytes and macrophages undergo M1-type inflammatory polarization in response to high levels of glucose.

    PubMed

    Torres-Castro, Israel; Arroyo-Camarena, Úrsula D; Martínez-Reyes, Camilo P; Gómez-Arauz, Angélica Y; Dueñas-Andrade, Yareth; Hernández-Ruiz, Joselín; Béjar, Yadira L; Zaga-Clavellina, Verónica; Morales-Montor, Jorge; Terrazas, Luis I; Kzhyshkowska, Julia; Escobedo, Galileo

    2016-08-01

    Emerging data suggest that elevated glucose may promote inflammatory activation of monocytic lineage cells with the ability to injure vascular endothelial tissue of diabetic patients, however evidence in primary human monocytes and macrophages is still insufficient. We investigated the effect of high glucose concentration on the inflammatory capacity of human macrophages in vitro and examined whether similar responses were detectable in circulating monocytes from prediabetic patients. Primary monocytes were isolated from healthy blood donors and differentiated into macrophages. Differentiated macrophages were exposed to normal levels of glucose (NG), high glucose (HG) or high mannitol as osmotic pressure control (OP) for three days. Using PCR, ELISA and flow cytometry, we found that HG macrophages showed overexpression of CD11c and inducible nitric oxide synthase as well as down-regulation of arginase-1 and interleukin (IL)-10 with respect to NG and OP macrophages. Consistent with in vitro results, circulating monocytes from hyperglycemic patients exhibited higher levels of CD11c and lower expression of CD206 than monocytes from normoglycemic controls. In subjects with hyperglycemia, elevation in CD11c(+) monocytes was associated with increased obesity, insulin resistance, and triglyceridemia as well as low serum IL-10. Our data suggest that human monocytes and macrophages undergo M1-like inflammatory polarization when exposed to high levels of glucose on in vitro culture conditions and in patients with hyperglycemia. These results demonstrate that excess glucose has direct effects on macrophage activation though the molecular mechanisms mediating such a response remain to be elucidated. PMID:27269375

  15. Galectin-12 enhances inflammation by promoting M1 polarization of macrophages and reduces insulin sensitivity in adipocytes.

    PubMed

    Wan, Lei; Lin, Hui-Ju; Huang, Chi-Chun; Chen, Ying-Chi; Hsu, Yu-An; Lin, Chia-Hung; Lin, Hsiu-Chu; Chang, Ching-Yao; Huang, Su-Hua; Lin, Jane-Ming; Liu, Fu-Tong

    2016-07-01

    Galectin-12 is a member of an animal lectin family with affinity for β-galactosides and containing consensus amino acid sequences. Here, we found that galectin-12 was expressed in macrophages and thus aimed to determine how galectin-12 affects inflammation and macrophage polarization and activation. The ablation of galectin-12 did not affect bone marrow cells to differentiate into macrophages, but reduced phagocytic activity against Escherichia coli and lowered the secretion of nitric oxide. The ablation of galectin-12 also resulted in the polarization of macrophages into the M2 direction, as indicated by increases in the levels of M2 markers, namely, resistin-like β (FIZZ1) and chitinase 3-like 3 (Ym1), as well as a reduction in the expression levels of a number of M1 pro-inflammatory cytokines. We found that the diminished expression of pro-inflammatory cytokines in macrophages resulting from galectin-12 deletion was due to reduced activation of IKKα/β, Akt and ERK, which in turn caused decreased activation of NF-κB and activator protein 1. The activation of STAT3 was much higher in Gal12(-/-) macrophages activated by lipopolysaccharide, which was correlated with higher levels of IL-10. Adipocytes showed higher insulin sensitivity when treated with Gal12(-/-) macrophage-conditioned media than those treated with Gal12(+/+) macrophages. We conclude galectin-12 negatively regulates macrophage polarization into the M2 population, resulting in enhanced inflammatory responses and also in turn causing decreased insulin sensitivity in adipocytes. This has implications in the treatment of a wide spectrum of metabolic disorders.

  16. Curcumin retunes cholesterol transport homeostasis and inflammation response in M1 macrophage to prevent atherosclerosis.

    PubMed

    Chen, Fang-Yuan; Zhou, Juan; Guo, Ning; Ma, Wang-Ge; Huang, Xin; Wang, Huan; Yuan, Zu-Yi

    2015-11-27

    Lipoprotein cholesterol metabolism dysfunction in the arterial wall is a major contributor to atherosclerosis, and excessive lipid intake and failed cholesterol homeostasis may accelerate the atherogenic process. Curcumin exerts multiple effects by alleviating inflammation, hyperlipidemia, and atherosclerosis; however, its role in cholesterol transport homeostasis and its underlying impact on inflammatory M1 macrophages are poorly understood. This work aimed to investigate the effect of curcumin on cholesterol transport, the inflammatory response and cell apoptosis in M1 macrophages. RAW264.7 macrophages (M0) were induced with LPS plus IFN-γ for 12 h to develop a M1 subtype and were then incubated with curcumin at different concentrations (6.25 and 12.5 μmol/L) in the presence or absence of oxLDL. Then, cholesterol influx/efflux and foam cell formation as well as inflammation and apoptosis were evaluated. It was found that curcumin increased cholesterol uptake measured by the Dil-oxLDL binding assay, and simultaneously increased cholesterol efflux carried out by Apo-A1 and HDL in M1 cells. Curcumin further reinforced ox-LDL-induced cholesterol esterification and foam cell formation as determined by Oil Red O and BODIPY staining. Moreover, curcumin dramatically reduced ox-LDL-induced cytokine production such as IL-1β, IL-6 as well as TNF-α and M1 cell apoptosis. We also found that curcumin upregulated CD36 and ABCA1 in M1 macrophages. Curcumin increased PPARγ expression, which in turn promoted CD36 and ABCA1 expression. In conclusion, curcumin may increase the ability of M1 macrophages to handle harmful lipids, thus promoting lipid processing, disposal and removal, which may support cholesterol homeostasis and exert an anti-atherosclerotic effect.

  17. Dynamic Changes of Microglia/Macrophage M1 and M2 Polarization in Theiler's Murine Encephalomyelitis.

    PubMed

    Herder, Vanessa; Iskandar, Cut Dahlia; Kegler, Kristel; Hansmann, Florian; Elmarabet, Suliman Ahmed; Khan, Muhammad Akram; Kalkuhl, Arno; Deschl, Ulrich; Baumgärtner, Wolfgang; Ulrich, Reiner; Beineke, Andreas

    2015-11-01

    Microglia and macrophages play a central role for demyelination in Theiler's murine encephalomyelitis (TME) virus infection, a commonly used infectious model for chronic-progressive multiple sclerosis. In order to determine the dynamic changes of microglia/macrophage polarization in TME, the spinal cord of Swiss Jim Lambert (SJL) mice was investigated by gene expression profiling and immunofluorescence. Virus persistence and demyelinating leukomyelitis were confirmed by immunohistochemistry and histology. Electron microscopy revealed continuous myelin loss together with abortive myelin repair during the late chronic infection phase indicative of incomplete remyelination. A total of 59 genes out of 151 M1- and M2-related genes were differentially expressed in TME virus-infected mice over the study period. The onset of virus-induced demyelination was associated with a dominating M1 polarization, while mounting M2 polarization of macrophages/microglia together with sustained prominent M1-related gene expression was present during the chronic-progressive phase. Molecular results were confirmed by immunofluorescence, showing an increased spinal cord accumulation of CD16/32(+) M1-, arginase-1(+) M2- and Ym1(+) M2-type cells associated with progressive demyelination. The present study provides a comprehensive database of M1-/M2-related gene expression involved in the initiation and progression of demyelination supporting the hypothesis that perpetuating interaction between virus and macrophages/microglia induces a vicious circle with persistent inflammation and impaired myelin repair in TME.

  18. A novel strain of Bacteroides fragilis enhances phagocytosis and polarises M1 macrophages

    PubMed Central

    Deng, Huimin; Li, Zhengchao; Tan, Yafang; Guo, Zhaobiao; Liu, Yangyang; Wang, Ye; Yuan, Yuan; Yang, Ruifu; Bi, Yujing; Bai, Yang; Zhi, Fachao

    2016-01-01

    Commensal Bacteroides fragilis possesses immune-regulatory characteristics. Consequently, it has been proposed as a potential novel probiotic because of its therapeutic effects on immune imbalance, mental disorders and inflammatory diseases. Macrophages play a central role in the immune response, developing either a classical-M1 or an alternative-M2 phenotype after stimulation with various signals. The interactions between macrophages and B. fragilis, however, remain to be defined. Here, a new isolate of B. fragilis, ZY-312, was shown to possess admirable properties, including tolerance to simulated gastric fluid, intestinal fluid and ox bile, and good safety (MOI = 100, 200) and adherent ability (MOI = 100) to LoVo cells. Isolate ZY-312 cell lysate promoted phagocytosis of fluorescent microspheres and pathogenic bacteria in bone marrow-derived macrophage (BMDM) cells. Gene expression of IL-12, iNOS and IL-1β in BMDM cells was increased after treatment with ZY-312, indicating the induction of M1 macrophages, consistent with enhanced secretion of NO. Cell surface expression of CD80 and CD86 was also increased. This study is the first to demonstrate that B. fragilis enhances the phagocytic functions of macrophages, polarising them to an M1 phenotype. Our findings provide insight into the close relationship between B. fragilis and the innate immune system. PMID:27381366

  19. Identity Crisis: CD301b(+) Mononuclear Phagocytes Blur the M1-M2 Macrophage Line.

    PubMed

    Knudsen, Nelson H; Lee, Chih-Hao

    2016-09-20

    Obesity shifts the immune phenotype from M2 macrophage polarization to M1, which causes metabolic dysfunction. In this issue of Immunity, Kumamoto et al. (2016) identify a tissue-resident mononuclear phagocyte population that promotes weight gain and glucose intolerance but are defined by the M2 marker CD301b. PMID:27653596

  20. Identity Crisis: CD301b(+) Mononuclear Phagocytes Blur the M1-M2 Macrophage Line.

    PubMed

    Knudsen, Nelson H; Lee, Chih-Hao

    2016-09-20

    Obesity shifts the immune phenotype from M2 macrophage polarization to M1, which causes metabolic dysfunction. In this issue of Immunity, Kumamoto et al. (2016) identify a tissue-resident mononuclear phagocyte population that promotes weight gain and glucose intolerance but are defined by the M2 marker CD301b.

  1. Programmed death 1 deficiency induces the polarization of macrophages/microglia to the M1 phenotype after spinal cord injury in mice.

    PubMed

    Yao, Anhui; Liu, Fangfang; Chen, Kun; Tang, Liang; Liu, Ling; Zhang, Kun; Yu, Caiyong; Bian, Ganlan; Guo, Hongmin; Zheng, Jingjing; Cheng, Peng; Ju, Gong; Wang, Jian

    2014-07-01

    The inflammatory response following spinal cord injury (SCI) involves the activation of resident microglia and the infiltration of macrophages. Macrophages and microglia can be polarized into the classically activated proinflammatory M1 phenotype or the alternatively activated anti-inflammatory M2 phenotype. Programmed cell death 1 (PD-1) is a critical immune inhibitory receptor involved in innate and adaptive immune responses. However, whether PD-1 is involved in the modulation of macrophage/microglial polarization is unknown. In this study, the mRNA levels of pd1 gradually increased after SCI, and PD-1 protein was found in macrophages/microglia in injured spinal cord sections. PD-1 knockout (KO) mice showed poor locomotor recovery after spinal cord crushing compared with wild-type mice. M1-type macrophages/microglia accumulated in greater numbers in the injured spinal cord of PD-1-KO mice. Under polarized stimulation, induced expression of PD-1 occurred in cultured macrophages and microglia. PD-1 suppressed M1 polarization by reducing the phosphorylation of signal transducer and activator of transcription 1 (STAT1) and promoted M2 polarization by increasing STAT6 phosphorylation. In PD-1-KO mice, the M1 response was enhanced via the activation of STAT1 and nuclear factor-kappa B. Furthermore, PD-1 played various roles in phagocytosis in macrophages and microglia. Therefore, our results suggest that PD-1 signaling plays an important role in the regulation of macrophage/microglial polarization. Thus, deregulated PD-1 signaling may induce the polarization of macrophages/microglia toward the M1 phenotype. Overall, our results provide new insights into the modulatory mechanisms of macrophage/microglial polarization, thereby possibly facilitating the development of new therapies for SCI via the regulation of macrophage/microglial polarization through PD-1 signaling.

  2. Targeting CD64 mediates elimination of M1 but not M2 macrophages in vitro and in cutaneous inflammation in mice and patient biopsies

    PubMed Central

    Hristodorov, Dmitrij; Mladenov, Radoslav; von Felbert, Verena; Huhn, Michael; Fischer, Rainer; Barth, Stefan; Thepen, Theo

    2015-01-01

    Macrophages are key players in controlling the immune response that can adapt to microenvironmental signals. This results in distinct polarization states (classical M1 or alternative M2), that play a differential role in immune regulation. In general, the M1 contribute to onset of inflammation, whereas the M2 orchestrate resolution and repair, whereby failure to switch from predominantly M1 to M2 reinforces a pro-inflammatory environment and chronic inflammation. Here, we show selective elimination of M1 macrophages in vitro by a range of CD64-targeted immunotoxins, including H22(scFv)-ETA'. After re-polarization of already polarized macrophages, still only M1 polarization showed sensitivity toward CD64-directed immunotoxins. The selectivity for M1 was found linked to reduced endosomal protease activity in M1 macrophages as demonstrated by inhibition of endosomal proteases. Using the H22(scFv)-ETA' in a transgenic mouse model for chronic cutaneous inflammation, the M1 specificity was confirmed in vivo and a beneficial effect on inflammation demonstrated. Also ex vivo on skin biopsies from atopic dermatitis and diabetes type II patients with chronically-inflamed skin, a clear M1 specific effect was found. This indicates the potential relevance for human application. Our data show that targeting M1 macrophages through CD64 can be instrumental in developing novel intervention strategies for chronic inflammatory conditions. PMID:26218624

  3. Low shear stress induces M1 macrophage polarization in murine thin-cap atherosclerotic plaques.

    PubMed

    Seneviratne, Anusha N; Cole, Jennifer E; Goddard, Michael E; Park, Inhye; Mohri, Zahra; Sansom, Stephen; Udalova, Irina; Krams, Rob; Monaco, Claudia

    2015-12-01

    Macrophages, a significant component of atherosclerotic plaques vulnerable to acute complications, can be pro-inflammatory (designated M1), regulatory (M2), lipid- (Mox) or Heme-induced (Mhem). We showed previously that low (LSS) and oscillatory (OSS) shear stress cause thin-cap fibroatheroma and stable smooth muscle cell-rich plaque formation respectively in ApoE-knockout (ApoE(-/-)) mice. Here we investigated whether different shear stress conditions relate to specific changes in macrophage polarization and plaque morphology by applying a shear stress-altering cast to the carotid arteries of high fat-fed ApoE(-/-) mice. The M1 markers iNOS and IRF5 were highly expressed in macrophage-rich areas of LSS lesions compared to OSS lesions 6weeks after cast placement, while the M2 marker Arginase-1, and Mox/Mhem markers HO-1 and CD163 were elevated in OSS lesions. Our data indicates shear stress could be an important determinant of macrophage polarization in atherosclerosis, with low shear promoting M1 programming.

  4. CD68(+)HLA-DR(+) M1-like macrophages promote motility of HCC cells via NF-κB/FAK pathway.

    PubMed

    Wang, Hao; Wang, Xianteng; Li, Xia; Fan, Yuchen; Li, Guosheng; Guo, Chun; Zhu, Faliang; Zhang, Lining; Shi, Yongyu

    2014-04-01

    TAM is a prominent component of inflammatory microenvironment, presenting M1 and M2 polarized states in HCC. The objective of this study is to investigate the relationship between M1-polarized macrophages and metastasis in HCC. We used immunohistochemical double-staining method to inspect the infiltration of CD68(+)HLA-DR(+) M1-like macrophages in HCC tissues. The M1-polarized macrophage was derived from THP-1 cell treated by LPS and IFN-γ in vitro. Transwell migration assay was used to evaluate whether the M1-polarized macrophage enhanced motility of HCC cells in the presence or absence of NF-κB inhibitor Bay 11-7802. The activation of NF-κB and FAK signaling pathways was examined by Western blot assay. Our results showed that the density of CD68(+)HLA-DR(+) TAM in the HCC with metastasis is significantly higher than that in the HCC without metastasis. Moreover, the conditioned medium from the M1 macrophages promote the migration of HCC cells and induced the activation of NF-κB and FAK signaling. The promoted migration of HCC cells was abrogated by the Bay 11-7802, as well as the activation of NF-κB and FAK pathway. Our findings implied a pro-metastatic role of M1-like TAM in HCC.

  5. 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.

  6. 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. PMID:23375938

  7. Monocyte Differentiation towards Protumor Activity Does Not Correlate with M1 or M2 Phenotypes

    PubMed Central

    Chimal-Ramírez, G. Karina; Espinoza-Sánchez, Nancy Adriana; Chávez-Sánchez, Luis; Arriaga-Pizano, Lourdes

    2016-01-01

    Macrophages facilitate breast cancer progression. Macrophages were initially classified as M1 or M2 based on their distinct metabolic programs and then expanded to include antitumoral (M1) and protumoral (M2) activities. However, it is still uncertain what markers define the pro- and antitumoral phenotypes and what conditions lead to their formation. In this study, monocytic cell lines and primary monocytes were subjected to commonly reported protocols of M1/M2 polarization and conditions known to engage monocytes into protumoral functions. The results showed that only IDO enzyme and CD86 M1 markers were upregulated correlating with M1 polarization. TNF-α, CCR7, IL-10, arginase I, CD36, and CD163 were expressed indistinguishably from M1 or M2 polarization. Similarly, protumoral engaging resulted in upregulation of both M1 and M2 markers, with conditioned media from the most aggressive breast cancer cell line promoting the greatest changes. In spite of the mixed phenotype, M1-polarized macrophages exhibited the highest expression/secretion of inflammatory mediators, many of which have previously been associated with breast cancer aggressiveness. These data argue that although the existence of protumoral macrophages is unquestionable, their associated phenotypes and the precise conditions driving their formation are still unclear, and those conditions may need both M1 and M2 stimuli. PMID:27376091

  8. Lactobacillus plantarum CLP-0611 ameliorates colitis in mice by polarizing M1 to M2-like macrophages.

    PubMed

    Jang, Se-Eun; Han, Myung Joo; Kim, Se-Young; Kim, Dong-Hyun

    2014-07-01

    The TNF-α expression-inhibitory effect of lactic acid bacteria (LAB) isolated from kimchi were measured in lipopolysaccharide (LPS)-stimulated peritoneal macrophages. Among the LAB evaluated, Lactobacillus plantarum CLP-0611 inhibited the IL-1β and IL-6 expression, as well as the NF-κB and AP1 activation in LPS-stimulated peritoneal macrophages. Therefore, we investigated its inhibitory effect on 2,4,6-trinitrobenzene sulfonic acid (TNBS)-induced colitis in mice. TNBS significantly induced colon shortening, as well as myeloperoxidase activity and macroscopic score. Oral administration of CLP-0611 significantly reduced TNBS-induced body weight loss, colon shortening, myeloperoxidase activity, IRAK-1 phosphorylation, NF-κB and MAP kinase (p38, ERK, JNK) activation, and iNOS and COX-2 expression. CLP-0611 also inhibited TNBS-induced expression of TNF-α, IL-1β, and IL-6. However, IL-10 expression was induced. CLP-0611 also induced the production of M2 macrophage markers (IL-10, arginase I and CD206). Based on these findings, CLP-0611 inhibits TLR-4-linked NF-κB and MAPK signaling pathways and polarizes M1 to M2-like macrophages, thus ameliorating colitis.

  9. Macrophage M1/M2 polarization dynamically adapts to changes in cytokine microenvironments in Cryptococcus neoformans infection.

    PubMed

    Davis, Michael J; Tsang, Tiffany M; Qiu, Yafeng; Dayrit, Jeremy K; Freij, Joudeh B; Huffnagle, Gary B; Olszewski, Michal A

    2013-06-18

    The outcome of cryptococcal pneumonia correlates with local macrophage polarization status, as M1 and M2 polarization marks protective and nonprotective responses, respectively. Overall, pulmonary macrophage polarization status changes over time during a cryptococcal infection. This could have been caused by repolarization of individual macrophages or by a replacement of M2-polarized cells by new M1-polarized cells. To explore the ability of macrophages to change between polarization states, we conducted a series of experiments using in vitro macrophages. Coculture of macrophages with Cryptococcus neoformans resulted in development of a weak M1-like phenotype, with modestly increased inducible nitric oxide synthase (iNOS) but lacking interleukin 6 (IL-6) induction. The C. neoformans-induced M1-like polarization state was plastic, as macrophages stimulated first with C. neoformans and then with gamma interferon (IFN-γ) or IL-4 expressed mRNA polarization patterns similar to those stimulated with cytokines alone. To further evaluate macrophage polarization plasticity, cytokine stimulatory conditions were established which fully polarized macrophages. IFN-γ and IL-4 stimulation differentially induced complete M1 and M2 polarization, defined by differential expression of marker mRNA panels, surface marker expression, and tumor necrosis factor alpha (TNF-α) protein production. Switching IFN-γ- to IL-4-stimulating conditions, and vice versa, resulted in uniform changes in profiles of polarization marker genes consistent with the most recent cytokine environment. Furthermore, the ability of sequentially stimulated macrophages to inhibit C. neoformans reflected the most recent polarizing condition, independent of previous polarization. Collectively, these data indicate that M1/M2 macrophage polarization phenotypes are highly plastic to external signals, and interventions which therapeutically repolarize macrophages could be beneficial for treatment of cryptococcosis.

  10. M1 muscarinic receptor activation mediates cell death in M1-HEK293 cells.

    PubMed

    Graham, E Scott; Woo, Kerhan K; Aalderink, Miranda; Fry, Sandie; Greenwood, Jeffrey M; Glass, Michelle; Dragunow, Mike

    2013-01-01

    HEK293 cells have been used extensively to generate stable cell lines to study G protein-coupled receptors, such as muscarinic acetylcholine receptors (mAChRs). The activation of M1 mAChRs in various cell types in vitro has been shown to be protective. To further investigate M1 mAChR-mediated cell survival, we generated stable HEK293 cell-lines expressing the human M1 mAChR. M1 mAChRs were efficiently expressed at the cell surface and efficiently internalised within 1 h by carbachol. Carbachol also induced early signalling cascades similar to previous reports. Thus, ectopically expressed M1 receptors behaved in a similar fashion to the native receptor over short time periods of analysis. However, substantial cell death was observed in HEK293-M1 cells within 24 h after carbachol application. Death was only observed in HEK cells expressing M1 receptors and fully blocked by M1 antagonists. M1 mAChR-stimulation mediated prolonged activation of the MEK-ERK pathway and resulted in prolonged induction of the transcription factor EGR-1 (>24 h). Blockade of ERK signalling with U0126 did not reduce M1 mAChR-mediated cell-death significantly but inhibited the acute induction of EGR-1. We investigated the time-course of cell death using time-lapse microscopy and xCELLigence technology. Both revealed the M1 mAChR cytotoxicity occurs within several hours of M1 activation. The xCELLigence assay also confirmed that the ERK pathway was not involved in cell-death. Interestingly, the MEK blocker did reduce carbachol-mediated cleaved caspase 3 expression in HEK293-M1 cells. The HEK293 cell line is a widely used pharmacological tool for studying G-protein coupled receptors, including mAChRs. Our results highlight the importance of investigating the longer term fate of these cells in short term signalling studies. Identifying how and why activation of the M1 mAChR signals apoptosis in these cells may lead to a better understanding of how mAChRs regulate cell-fate decisions.

  11. Interleukin-17A neutralization alleviated ocular neovascularization by promoting M2 and mitigating M1 macrophage polarization.

    PubMed

    Zhu, Yanji; Tan, Wei; Demetriades, Anna M; Cai, Yujuan; Gao, Yushuo; Sui, Ailing; Lu, Qing; Shen, Xi; Jiang, Chunhui; Xie, Bing; Sun, Xinghuai

    2016-04-01

    Neovascularization (NV), as a cardinal complication of several ocular diseases, has been intensively studied, and research has shown its close association with inflammation and immune cells. In the present study, the role of interleukin-17A (IL-17A) in angiogenesis in the process of ocular NV both in vivo and in vitro was investigated. Also, a paracrine role of IL-17A was demonstrated in the crosstalk between endothelial cells and macrophages in angiogenesis. In the retinas of mice with retinopathy of prematurity, the IL-17A expression increased significantly at postnatal day 15 (P15) and P18 during retinal NV. Mice given IL-17A neutralizing antibody (NAb) developed significantly reduced choroidal NV and retinal NV. Studies on vascular endothelial growth factor (VEGF) over-expressing mice suggested that IL-17A modulated NV through the VEGF pathway. Furthermore, IL-17A deficiency shifted macrophage polarization toward an M2 phenotype during retinal NV with significantly reduced M1 cytokine expression compared with wild-type controls. In vitro assays revealed that IL-17A treated macrophage supernatant gave rise to elevated human umbilical vascular endothelial cell proliferation, tube formation and VEGF receptor 1 and receptor 2 expression. Therefore, IL-17A could potentially serve as a novel target for treating ocular NV diseases. The limitation of this study involved the potential mechanisms, such as which transcription accounted for macrophage polarization and how the subsequent cytokines were modulated when macrophages were polarized. Further studies need to be undertaken to definitively determine the extent to which IL-17A neutralizing anti-angiogenic activity depends on macrophage modulation compared with anti-VEGF treatment.

  12. Fully human MAP-fusion protein selectively targets and eliminates proliferating CD64(+) M1 macrophages.

    PubMed

    Hristodorov, Dmitrij; Mladenov, Radoslav; Fischer, Rainer; Barth, Stefan; Thepen, Theo

    2016-05-01

    Classical immunotoxins compromise a binding component (for example, a ligand, antibody or fragment thereof) and a cytotoxic component, usually derived from bacteria or plants (for example, Pseudomonas exotoxin A or ricin). Despite successful testing in vitro, the clinical development of immunotoxins has been hampered by immunogenicity and unsatisfactory safety profiles. Therefore, research has focused on fully human pro-apoptotic components suitable for the development of cytolytic fusion proteins (CFP). We recently reported that human microtubule-associated protein tau (MAP) can induce apoptosis when delivered to rapidly proliferating cancer cells. Here, we describe a new fully human CFP called H22(scFv)-MAP, which specifically targets CD64(+) cells. We show that H22(scFv)-MAP can efficiently kill proliferating HL-60 pro-monocytic cells in vitro. In addition, the human CFP specifically eliminates polarized M1 macrophages in a transgenic mouse model of cutaneous chronic inflammation. Because M1 macrophages promote the pathogenesis of many chronic inflammatory diseases, targeting this cell population with H22(scFv)-MAP could help to treat diseases such as atopic dermatitis, rheumatoid arthritis and inflammatory bowel disease.

  13. M1- and M2-Type Macrophage Responses Are Predictive of Adverse Outcomes in Human Atherosclerosis

    PubMed Central

    de Gaetano, Monica; Crean, Daniel; Barry, Mary; Belton, Orina

    2016-01-01

    Atherosclerosis is an inflammatory disease caused by endothelial injury, lipid deposition, and oxidative stress. This progressive disease can be converted into an acute clinical event by plaque rupture and thrombosis. In the context of atherosclerosis, the underlying cause of myocardial infarction and stroke, macrophages uniquely possess a dual functionality, regulating lipid accumulation and metabolism and sustaining the chronic inflammatory response, two of the most well-documented pathways associated with the pathogenesis of the disease. Macrophages are heterogeneous cell populations and it is hypothesized that, during the pathogenesis of atherosclerosis, macrophages in the developing plaque can switch from a pro-inflammatory (MΦ1) to an anti-inflammatory (MΦ2) phenotype and vice versa, depending on the microenvironment. The aim of this study was to identify changes in macrophage subpopulations in the progression of human atherosclerotic disease. Established atherosclerotic plaques from symptomatic and asymptomatic patients with existing coronary artery disease undergoing carotid endarterectomy were recruited to the study. Comprehensive histological and immunohistochemical analyses were performed to quantify the cellular content and macrophage subsets of atherosclerotic lesion. In parallel, expression of MΦ1 and MΦ2 macrophage markers were analyzed by real-time PCR and Western blot analysis. Gross analysis and histological staining demonstrated that symptomatic plaques presented greater hemorrhagic activity and the internal carotid was the most diseased segment, based on the predominant prevalence of fibrotic and necrotic tissue, calcifications, and hemorrhagic events. Immunohistochemical analysis showed that both MΦ1 and MΦ2 macrophages are present in human plaques. However, MΦ2 macrophages are localized to more stable locations within the lesion. Importantly, gene and protein expression analysis of MΦ1/MΦ2 markers evidenced that MΦ1 markers and Th1

  14. M1- and M2-Type Macrophage Responses Are Predictive of Adverse Outcomes in Human Atherosclerosis.

    PubMed

    de Gaetano, Monica; Crean, Daniel; Barry, Mary; Belton, Orina

    2016-01-01

    Atherosclerosis is an inflammatory disease caused by endothelial injury, lipid deposition, and oxidative stress. This progressive disease can be converted into an acute clinical event by plaque rupture and thrombosis. In the context of atherosclerosis, the underlying cause of myocardial infarction and stroke, macrophages uniquely possess a dual functionality, regulating lipid accumulation and metabolism and sustaining the chronic inflammatory response, two of the most well-documented pathways associated with the pathogenesis of the disease. Macrophages are heterogeneous cell populations and it is hypothesized that, during the pathogenesis of atherosclerosis, macrophages in the developing plaque can switch from a pro-inflammatory (MΦ1) to an anti-inflammatory (MΦ2) phenotype and vice versa, depending on the microenvironment. The aim of this study was to identify changes in macrophage subpopulations in the progression of human atherosclerotic disease. Established atherosclerotic plaques from symptomatic and asymptomatic patients with existing coronary artery disease undergoing carotid endarterectomy were recruited to the study. Comprehensive histological and immunohistochemical analyses were performed to quantify the cellular content and macrophage subsets of atherosclerotic lesion. In parallel, expression of MΦ1 and MΦ2 macrophage markers were analyzed by real-time PCR and Western blot analysis. Gross analysis and histological staining demonstrated that symptomatic plaques presented greater hemorrhagic activity and the internal carotid was the most diseased segment, based on the predominant prevalence of fibrotic and necrotic tissue, calcifications, and hemorrhagic events. Immunohistochemical analysis showed that both MΦ1 and MΦ2 macrophages are present in human plaques. However, MΦ2 macrophages are localized to more stable locations within the lesion. Importantly, gene and protein expression analysis of MΦ1/MΦ2 markers evidenced that MΦ1 markers and Th1

  15. M1/M2-macrophage phenotypes regulate renal calcium oxalate crystal development

    PubMed Central

    Taguchi, Kazumi; Okada, Atsushi; Hamamoto, Shuzo; Unno, Rei; Moritoki, Yoshinobu; Ando, Ryosuke; Mizuno, Kentaro; Tozawa, Keiichi; Kohri, Kenjiro; Yasui, Takahiro

    2016-01-01

    In our previous report, M2-macrophage (Mφs) deficient mice showed increased renal calcium oxalate (CaOx) crystal formation; however, the role of Mφs-related-cytokines and chemokines that affect kidney stone formation remains unknown. Here, we investigated the role of M1/M2s in crystal development by using in vitro and in vivo approaches. The crystal phagocytic rate of bone marrow-derived M2Mφs was higher than that of bone marrow-derived Mφs and M1Mφs and increased on co-culture with renal tubular cells (RTCs). However, the amount of crystal attachment on RTCs reduced on co-culture with M2Mφs. In six hyperoxaluric C57BL/6J mice, M1Mφ transfusion and induction by LPS and IFN-γ facilitated renal crystal formation, whereas M2Mφ transfusion and induction by IL-4 and IL-13 suppressed renal crystal formation compared with the control. These M2Mφ treatments reduced the expression of crystal-related genes, such as osteopontin and CD44, whereas M1Mφ treatment increased the expression of pro-inflammatory and adhesion-related genes such as IL-6, inducible NOS, TNF-α, C3, and VCAM-1. The expression of M2Mφ-related genes was lower whereas that of M1Mφ-related genes was higher in papillary tissue of CaOx stone formers. Overall, our results suggest that renal crystal development is facilitated by M1Mφs, but suppressed by M2Mφs. PMID:27731368

  16. M2/M1 ratio of tumor associated macrophages and PPAR-gamma expression in uveal melanomas with class 1 and class 2 molecular profiles.

    PubMed

    Herwig, Martina C; Bergstrom, Chris; Wells, Jill R; Höller, Tobias; Grossniklaus, Hans E

    2013-02-01

    Macrophages have been found to be negative predictors of outcome in patients with uveal melanoma. In particular, recent studies point toward a disease-progressing role of proangiogenic M2 macrophages in melanomas with monosomy 3. Although most studies implicate a protective effect of PPAR-gamma activation in tumors, PPAR-gamma has also been shown to promote the polarization of M1 macrophages toward the M2 phenotype. The purpose of this investigation was first, to characterize the phenotype of tumor infiltrating macrophages and second, to study PPAR-gamma expression in uveal melanomas with molecular gene expression profile as prognostic predictors for patients' outcome. Twenty specimens from patients with uveal melanoma were analyzed for clinical and histologic tumor characteristics. The molecular RNA profile (class 1 or class 2) was commercially determined. Using immunohistochemical techniques, the specimens were dual labeled for CD68 and CD163. CD68 + CD163- M1 macrophages and CD68 + CD163+ M2 macrophages were analyzed in ten high power fields sparing macrophage-poor areas and a mean value was calculated for each tumor. The tumors were immunostained for von Willebrand factor and the micro vascular density (MVD) was analyzed according to Foss. To assess the proliferative rate of each tumor, Ki67 expression was evaluated in ten high power fields followed by calculation of a mean value. Expression of PPAR-gamma was evaluated using a score from 0 (no staining) to 3 (tumor entirely stained). Statistical analysis and a respective correlation were made between histologic characteristics, molecular profile, type of tumor infiltrating macrophages (M1 vs. M2), MVD, proliferative rate, and PPAR-gamma expression. Our results showed a correlation between the ratio of M2/M1 macrophages and the molecular profile with a ratio of approximately 1 corresponding to molecular class 1 and a ratio of approximately 2 corresponding to molecular class 2 (p = 0.01). The ratio of M2/M1

  17. Grapefruit-derived nanovectors deliver miR-18a for treatment of liver metastasis of colon cancer by induction of M1 macrophages

    PubMed Central

    Teng, Yun; Mu, Jingyao; Hu, Xin; Samykutty, Abhilash; Zhuang, Xiaoying; Deng, Zhongbin; Zhang, Lifeng; Cao, Pengxiao; Yan, Jun; Miller, Donald; Zhang, Huang-Ge

    2016-01-01

    Liver metastasis accounts for many of the cancer deaths in patients. Effective treatment for metastatic liver tumors is not available. Here, we provide evidence for the role of miR-18a in the induction of liver M1 (F4/80+interferon gamma (IFNγ)+IL-12+) macrophages. We found that miR-18a encapsulated in grapefruit-derived nanovector (GNV) mediated inhibition of liver metastasis that is dependent upon the induction of M1 (F4/80+IFNγ+IL-12+) macrophages; depletion of macrophages eliminated its anti-metastasis effect. Furthermore, the miR-18a mediated induction of macrophage IFNγ by targeting IRF2 is required for subsequent induction of IL-12. IL-12 then activates natural killer (NK) and natural killer T (NKT) cells for inhibition of liver metastasis of colon cancer. This conclusion is supported by the fact that knockout of IFNγ eliminates miR-18a mediated induction of IL-12, miR-18a treatment has an anti-metastatic effects in T cell deficient mice but there is no anti-metastatic effect on NK and NKT deficient mice. Co-delivery of miR-18a and siRNA IL-12 to macrophages did not result in activation of co-cultured NK and NKT cells. Taken together our results indicate that miR-18a can act as an inhibitor for liver metastasis through induction of M1 macrophages. PMID:27028860

  18. Cardiosphere-Derived Cells Facilitate Heart Repair by Modulating M1/M2 Macrophage Polarization and Neutrophil Recruitment

    PubMed Central

    Hasan, Al Shaimaa; Luo, Lan; Yan, Chen; Zhang, Tian-Xia; Urata, Yoshishige; Goto, Shinji; Mangoura, Safwat A.; Abdel-Raheem, Mahmoud H.; Zhang, Shouhua; Li, Tao-Sheng

    2016-01-01

    Cardiosphere-derived cells (CDCs), one of the promising stem cell sources for myocardial repair, have been tested in clinical trials and resulted in beneficial effects; however, the relevant mechanisms are not fully understood. In this study, we examined the hypothesis that CDCs favor heart repair by switching the macrophages from a pro-inflammatory phenotype (M1) into a regulatory anti-inflammatory phenotype (M2). Macrophages from mice were cultured with CDCs-conditioned medium or with fibroblasts-conditioned medium as a control. Immunostaining showed that CDCs-conditioned medium significantly enhanced the expression of CD206 (a marker for M2 macrophages), but decreased the expression of CD86 (a marker for M1 macrophages) 3 days after culture. For animal studies, we used an acute myocardial infarction model of mice. We injected CDCs, fibroblasts, or saline only into the border zone of infarction. Then we collected the heart tissues for histological analysis 5 and 14 days after treatment. Compared with control animals, CDCs treatment significantly decreased M1 macrophages and neutrophils but increased M2 macrophages in the infarcted heart. Furthermore, CDCs-treated mice had reduced infarct size and fewer apoptotic cells compared to the controls. Our data suggest that CDCs facilitate heart repair by modulating M1/M2 macrophage polarization and neutrophil recruitment, which may provide a new insight into the mechanisms of stem cell-based myocardial repair. PMID:27764217

  19. The Distribution of Macrophages with a M1 or M2 Phenotype in Relation to Prognosis and the Molecular Characteristics of Colorectal Cancer

    PubMed Central

    Dahlin, Anna M.; Rutegård, Jörgen; Öberg, Åke; Oldenborg, Per-Arne; Palmqvist, Richard

    2012-01-01

    High macrophage infiltration has been correlated to improved survival in colorectal cancer (CRC). Tumor associated macrophages (TAMs) play complex roles in tumorigenesis since they are believed to hold both tumor preventing (M1 macrophages) and tumor promoting (M2 macrophages) activities. Here we have applied an immunohistochemical approach to determine the degree of infiltrating macrophages with a M1 or M2 phenotype in clinical specimens of CRC in relation to prognosis, both in CRC in general but also in subgroups of CRC defined by microsatellite instability (MSI) screening status and the CpG island methylator phenotype (CIMP). A total of 485 consecutive CRC specimens were stained for nitric oxide synthase 2 (NOS2) (also denoted iNOS) as a marker for the M1 macrophage phenotype and the scavenger receptor CD163 as a marker for the M2 macrophage phenotype. The average infiltration of NOS2 and CD163 expressing macrophages along the invasive tumor front was semi-quantitatively evaluated using a four-graded scale. Two subtypes of macrophages, displaying M1 (NOS2+) or M2 (CD163+) phenotypes, were recognized. We observed a significant correlation between the amount of NOS2+ and CD163+ cells (P<0.0001). A strong inverse correlation to tumor stage was found for both NOS2 (P<0.0001) and CD163 (P<0.0001) infiltration. Furthermore, patients harbouring tumors highly infiltrated by NOS2+ cells had a significantly better prognosis than those infiltrated by few NOS2+ cells, and this was found to be independent of MSI screening status and CIMP status. No significant difference was found on cancer-specific survival in groups of CRC with different NOS2/CD163 ratios. In conclusion, an increased infiltration of macrophages with a M1 phenotype at the tumor front is accompanied by a concomitant increase in macrophages with a M2 phenotype, and in a stage dependent manner correlated to a better prognosis in patients with CRC. PMID:23077543

  20. CD200+ and CD200- macrophages accumulated in ischemic lesions of rat brain: the two populations cannot be classified as either M1 or M2 macrophages.

    PubMed

    Matsumoto, Shirabe; Tanaka, Junya; Yano, Hajime; Takahashi, Hisaaki; Sugimoto, Kana; Ohue, Shiro; Inoue, Akihiro; Aono, Hitomi; Kusakawa, Akari; Watanabe, Hideaki; Kumon, Yoshiaki; Ohnishi, Takanori

    2015-05-15

    Two types of macrophages in lesion core of rat stroke model were identified according to NG2 chondroitin sulfate proteoglycan (NG2) and CD200 expression. NG2(+) macrophages were CD200(-), and vice versa. NG2(-) macrophages expressed two splice variants of CD200 that are CD200L and CD200S. CD200(+) macrophages expressed CD8, CD68, CD163, CCL2, inducible nitric oxide synthase, interleukin-1β, Toll-like receptor 4 and transforming growth factor β, whilst NG2(+) cells expressed a costimulatory factor CD86. Both cell types expressed insulin-like growth factor 1 and CD200R. These results demonstrate that the two macrophage types cannot be classified as either M1 or M2. PMID:25903723

  1. PICK1 confers anti-inflammatory effects in acute liver injury via suppressing M1 macrophage polarization.

    PubMed

    Xie, Juan; Wu, Xiaoqin; Zhou, Qun; Yang, Yang; Tian, Yuanyao; Huang, Cheng; Meng, Xiaoming; Li, Jun

    2016-08-01

    Protein interacting with C kinase 1 (PICK1) is a scaffolding protein mainly implicated in neurological diseases, however, the function of PICK1 in acute liver injury (ALI) remains unknown. Our study found a dramatical decrease in mRNA and protein levels of PICK1 in liver tissues and isolated Kupffer cells (KCs) from the liver in mice with ALI. Furthermore, pretreatment the mice with ALI with FSC-231, a pharmacological inhibitor of PICK1, could significantly augment inflammatory response. Furthermore, in vitro studies showed that both lipopolysaccharide (LPS) and interferon gamma (IFN-γ) significantly reduced the expression of PICK1, while IL-4 elevated its expression in RAW 264.7 cells. Additionally, over-expression of PICK1 inhibited the expression of M1 biomarkers by suppressing NF-κB activity, and enhanced the expression of M2 biomarkers by promoting STAT6 activity. In contrast, knockdown of PICK1 or FSC-231 pretreatment promoted M1 polarization and suppressed M2 polarization. Besides, caveolin-1 was identified as a potential target gene controlled by PICK1 in RAW 264.7 cells. Mechanistic investigation revealed a dual role of PICK1 in regulating macrophage polarization and implied PICK1 as a potential therapeutic target in ALI.

  2. ABCG1 regulates mouse adipose tissue macrophage cholesterol levels and ratio of M1 to M2 cells in obesity and caloric restriction.

    PubMed

    Wei, Hao; Tarling, Elizabeth J; McMillen, Timothy S; Tang, Chongren; LeBoeuf, Renée C

    2015-12-01

    In addition to triacylglycerols, adipocytes contain a large reserve of unesterified cholesterol. During adipocyte lipolysis and cell death seen during severe obesity and weight loss, free fatty acids and cholesterol become available for uptake and processing by adipose tissue macrophages (ATMs). We hypothesize that ATMs become cholesterol enriched and participate in cholesterol clearance from adipose tissue. We previously showed that ABCG1 is robustly upregulated in ATMs taken from obese mice and further enhanced by caloric restriction. Here, we found that ATMs taken from obese and calorie-restricted mice derived from transplantation of WT or Abcg1-deficient bone marrow are cholesterol enriched. ABCG1 levels regulate the ratio of classically activated (M1) to alternatively activated (M2) ATMs and their cellular cholesterol content. Using WT and Abcg1(-/-) cultured macrophages, we found that Abcg1 is most highly expressed by M2 macrophages and that ABCG1 deficiency is sufficient to retard macrophage chemotaxis. However, changes in myeloid expression of Abcg1 did not protect mice from obesity or impaired glucose homeostasis. Overall, ABCG1 modulates ATM cholesterol content in obesity and weight loss regimes leading to an alteration in M1 to M2 ratio that we suggest is due to the extent of macrophage egress from adipose tissue.

  3. Plaque Size Is Decreased but M1 Macrophage Polarization and Rupture Related Metalloproteinase Expression Are Maintained after Deleting T-Bet in ApoE Null Mice

    PubMed Central

    Tsaousi, Aikaterini; Hayes, Elaine M.; Di Gregoli, Karina; Bond, Andrew R.; Bevan, Laura

    2016-01-01

    Background Thelper1 (Th1) lymphocytes have been previously implicated in atherosclerotic plaque growth but their role in plaque vulnerability to rupture is less clear. We investigated whether T-bet knockout that prevents Th1 lymphocyte differentiation modulates classical (M1) macrophage activation or production of matrix degrading metalloproteinases (MMPs) and their tissue inhibitors, TIMPs. Methods & Results We studied the effect of T-bet deletion in apolipoproteinE (ApoE) knockout mice fed a high fat diet (HFD) or normal chow diet (ND). Transcript levels of M1/M2 macrophage polarization markers, selected MMPs and TIMPs were measured by RT-qPCR in macrophages isolated from subcutaneous granulomas or in whole aortae. Immunohistochemistry of aortic sinus (AS) and brachiocephalic artery (BCA) plaques was conducted to quantify protein expression of the same factors. Deletion of T-bet decreased mRNA for the M1 marker NOS-2 in granuloma macrophages but levels of M2 markers (CD206, arginase-1 and Ym-1), MMPs-2, -9, -12, -13, -14 and -19 or TIMPs-1 to -3 were unchanged. No mRNA differences were observed in aortic extracts from mice fed a HFD for 12 weeks. Moreover, AS and BCA plaques were similarly sized between genotypes, and had similar areas stained for NOS-2, COX-2, MMP-12 and MMP-14 proteins. T-bet deletion increased MMP-13, MMP-14 and arginase-1 in AS plaques. After 35 weeks of ND, T-bet deletion reduced the size of AS and BCA plaques but there were no differences in the percentage areas stained for M1 or M2 markers, MMPs-12, -13, -14, or TIMP-3. Conclusions Absence of Th1 lymphocytes is associated with reduced plaque size in ApoE knockout mice fed a normal but not high fat diet. In either case, M1 macrophage polarization and expression of several MMPs related to plaque instability are either maintained or increased. PMID:26886778

  4. 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

  5. Secreted protein acidic and rich in cysteine facilitates age-related cardiac inflammation and macrophage M1 polarization

    PubMed Central

    Toba, Hiroe; de Castro Brás, Lisandra E.; Baicu, Catalin F.; Zile, Michael R.; Lindsey, Merry L.

    2015-01-01

    To investigate the role of secreted protein acidic and rich in cysteine (SPARC) in age-related cardiac inflammation, we studied six groups of mice: young (3–5 mo old), middle-aged (10–12 mo old), and old (18–29 mo old) C57BL/6 wild-type (WT) and SPARC-null (Null) mice (n = 7–10/group). Cardiac function and structure were determined by echocardiography. The left ventricle was used for cytokine gene array and macrophage quantification by immunohistochemistry. Macrophage infiltration increased with age in WT (n = 5–6/group, P < 0.05 for young vs. old), but not in Null. Proinflammatory markers (Ccl5, Cx3cl1, Ccr2, and Cxcr3) increased in middle-aged and old WT, whereas they were increased only in old Null compared with respective young (n = 5–6/group, P < 0.05 for all). These results suggest that SPARC deletion delayed age-related cardiac inflammation. To further assess how SPARC affects inflammation, we stimulated peritoneal macrophages with SPARC (n = 4). SPARC treatment increased expression of proinflammatory macrophage M1 markers and decreased anti-inflammatory M2 markers. Echocardiography (n = 7–10/group) revealed an age-related increase in wall thickness of the left ventricle in WT (0.76 ± 0.02 mm in young vs. 0.91 ± 0.03 mm in old; P < 0.05) but not in Null (0.78 ± 0.01 mm in young vs. 0.84 ± 0.02 mm in old). In conclusion, SPARC deletion delayed age-related increases in macrophage infiltration and proinflammatory cytokine expression in vivo and in vitro. SPARC acts as an important mediator of age-related cardiac inflammation by increasing the expression of macrophage M1 markers and decreasing M2 markers. PMID:25877699

  6. Human macrophage polarization in vitro: maturation and activation methods compared.

    PubMed

    Vogel, Daphne Y S; Glim, Judith E; Stavenuiter, Andrea W D; Breur, Marjolein; Heijnen, Priscilla; Amor, Sandra; Dijkstra, Christine D; Beelen, Robert H J

    2014-09-01

    Macrophages form a heterogeneous cell population displaying multiple functions, and can be polarized into pro- (M1) or anti-inflammatory (M2) macrophages, by environmental factors. Their activation status reflects a beneficial or detrimental role in various diseases. Currently several in vitro maturation and activation protocols are used to induce an M1 or M2 phenotype. Here, the impact of different maturation factors (NHS, M-CSF, or GM-CSF) and activation methods (IFN-γ/LPS, IL-4, dexamethason, IL-10) on the macrophage phenotype was determined. Regarding macrophage morphology, pro-inflammatory (M1) activation stimulated cell elongation, and anti-inflammatory (M2) activation induced a circular appearance. Activation with pro-inflammatory mediators led to increased CD40 and CD64 expression, whereas activation with anti-inflammatory factors resulted in increased levels of MR and CD163. Production of pro-inflammatory cytokines was induced by activation with IFN-γ/LPS, and TGF-β production was enhanced by the maturation factors M-CSF and GM-CSF. Our data demonstrate that macrophage marker expression and cytokine production in vitro is highly dependent on both maturation and activation methods. In vivo macrophage activation is far more complex, since a plethora of stimuli are present. Hence, defining the macrophage activation status ex vivo on a limited number of markers could be indecisive. From this study we conclude that maturation with M-CSF or GM-CSF induces a moderate anti- or pro-inflammatory state respectively, compared to maturation with NHS. CD40 and CD64 are the most distinctive makers for human M1 and CD163 and MR for M2 macrophage activation and therefore can be helpful in determining the activation status of human macrophages ex vivo.

  7. 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.

  8. PTEN inhibits macrophage polarization from M1 to M2 through CCL2 and VEGF-A reduction and NHERF-1 synergism.

    PubMed

    Li, Ning; Qin, Junfang; Lan, Lan; Zhang, Hongyao; Liu, Fang; Wu, Zhaozhen; Ni, Hong; Wang, Yue

    2015-01-01

    PTEN has been studied in several tumor models as a tumor suppressor. In this study, we explored the role of PTEN in the inhibition state of polarized M2 subtype of macrophage in tumor microenvironment (TME) and the underlying mechanisms. To elucidate the potential effect in TME, RAW 264.7 macrophages and 4T1 mouse breast cancer cells were co-cultured to reconstruct tumor microenvironment. After PTEN was down-regulated with shRNA, the expression of CCL2 and VEGF-A, which are definited to promote the formation of M2 macrophages, have a dramatically increase on the level of both gene and protein in co-cultured RAW 264.7 macrophages. And at the same time, NHERF-1 (Na(+)/H(+) exchanger regulating factor-1), another tumor suppressor has a similar tendency to PTEN. Q-PCR and WB results suggested that PTEN and NHERF-1 were consistent with one another no matter at mRNA or protein level when exposed to the same stimulus. Coimmunoprecipitation and immunofluorescence techniques confirmed that PTEN and NHERF-1 were coprecipitated, and NHERF-1 protein expression was properly reduced with rCCL2 effect. In addition, cell immunofluorescence images revealed a profound transferance, in co-cultured RAW 264.7 macrophages, an up-regulation of NHERF-1 could promote the PTEN marked expression on the cell membrane, and this form for the interaction was not negligible. These observations illustrate PTEN with a certain synergy of NHERF-1, as well as down-regulation of CCL2 suppressing M2 macrophage transformation pathway. The results suggest that the activation of PTEN and NHERF-1 may impede the evolution of macrophages beyond the M1 into M2 phenotype in tumor microenvironment.

  9. NOTCH reprograms mitochondrial metabolism for proinflammatory macrophage activation

    PubMed Central

    Xu, Jun; Chi, Feng; Guo, Tongsheng; Punj, Vasu; Lee, W.N. Paul; French, Samuel W.; Tsukamoto, Hidekazu

    2015-01-01

    Metabolic reprogramming is implicated in macrophage activation, but the underlying mechanisms are poorly understood. Here, we demonstrate that the NOTCH1 pathway dictates activation of M1 phenotypes in isolated mouse hepatic macrophages (HMacs) and in a murine macrophage cell line by coupling transcriptional upregulation of M1 genes with metabolic upregulation of mitochondrial oxidative phosphorylation and ROS (mtROS) to augment induction of M1 genes. Enhanced mitochondrial glucose oxidation was achieved by increased recruitment of the NOTCH1 intracellular domain (NICD1) to nuclear and mitochondrial genes that encode respiratory chain components and by NOTCH-dependent induction of pyruvate dehydrogenase phosphatase 1 (Pdp1) expression, pyruvate dehydrogenase activity, and glucose flux to the TCA cycle. As such, inhibition of the NOTCH pathway or Pdp1 knockdown abrogated glucose oxidation, mtROS, and M1 gene expression. Conditional NOTCH1 deficiency in the myeloid lineage attenuated HMac M1 activation and inflammation in a murine model of alcoholic steatohepatitis and markedly reduced lethality following endotoxin-mediated fulminant hepatitis in mice. In vivo monocyte tracking further demonstrated the requirement of NOTCH1 for the migration of blood monocytes into the liver and subsequent M1 differentiation. Together, these results reveal that NOTCH1 promotes reprogramming of mitochondrial metabolism for M1 macrophage activation. PMID:25798621

  10. Treatment in vitro with PPARα and PPARγ ligands drives M1-to-M2 polarization of macrophages from T. cruzi-infected mice.

    PubMed

    Penas, Federico; Mirkin, Gerardo A; Vera, Marcela; Cevey, Ágata; González, Cintia D; Gómez, Marisa I; Sales, María Elena; Goren, Nora B

    2015-05-01

    Trypanosoma cruzi, the etiological agent of Chagas' disease, induces a persistent inflammatory response. Macrophages are a first line cell phenotype involved in the clearance of infection. Upon parasite uptake, these cells increase inflammatory mediators like NO, TNF-α, IL-1β and IL-6, leading to parasite killing. Although desired, inflammatory response perpetuation and exacerbation may lead to tissue damage. Peroxisome proliferator-activated receptors (PPARs) are ligand-dependent nuclear transcription factors that, besides regulating lipid and carbohydrate metabolism, have a significant anti-inflammatory effect. This is mediated through the interaction of the receptors with their ligands. PPARγ, one of the PPAR isoforms, has been implicated in macrophage polarization from M1, the classically activated phenotype, to M2, the alternatively activated phenotype, in different models of metabolic disorders and infection. In this study, we show for the first time that, besides PPARγ, PPARα is also involved in the in vitro polarization of macrophages isolated from T. cruzi-infected mice. Polarization was evidenced by a decrease in the expression of NOS2 and proinflammatory cytokines and the increase in M2 markers like Arginase I, Ym1, mannose receptor and TGF-β. Besides, macrophage phagocytic activity was significantly enhanced, leading to increased parasite load. We suggest that modulation of the inflammatory response by both PPARs might be due, at least in part, to a change in the profile of inflammatory macrophages. The potential use of PPAR agonists as modulators of overt inflammatory response during the course of Chagas' disease deserves further investigation.

  11. 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

  12. 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

  13. A double feedback loop mediated by microRNA-23a/27a/24-2 regulates M1 versus M2 macrophage polarization and thus regulates cancer progression.

    PubMed

    Ma, Sisi; Liu, Min; Xu, Zhenbiao; Li, Yanshuang; Guo, Hui; Ge, Yehua; Liu, Yanxin; Zheng, Dexian; Shi, Juan

    2016-03-22

    In response to microenvironmental signals, macrophages undergo different types of activation, including the "classic" pro-inflammatory phenotype (also called M1) and the "alternative" anti-inflammatory phenotype (also called M2). Macrophage polarized activation has profound effects on immune and inflammatory responses, but mechanisms underlying the various types of macrophage is still in its infancy. In this study, we reported that M1-type stimulation could down-regulate miR-23a/27a/24-2 cluster transcription through the binding of NF-κB to this cluster's promoter and that miR-23a in turn activated the NF-κB pathway by targeting A20 and thus promoted the production of pro-inflammatory cytokines. Furthermore, STAT6 occupied the miR-23a/27a/24-2 cluster promoter and activated their transcription in IL-4-stimulated macrophages. In addition, miR-23a in turn suppressed the JAK1/STAT-6 pathway and reduced the production of M2 type cytokines by targeting JAK1 and STAT-6 directly, while miR-27a showed the same phenotype by targeting IRF4 and PPAR-γ. The miR-23a/27a/24-2 cluster was shown to be significantly decreased in TAMs of breast cancer patients, and macrophages overexpressing the miR-23a/27a/24-2 cluster inhibited tumor growth in vivo. Taken together, these data integrated microRNA expression and function into macrophage polarization networks and identified a double feedback loop consisting of the miR-23a/27a/24-2 cluster and the key regulators of the M1 and M2 macrophage polarization pathway. Moreover, miR-23a/27a/24-2 regulates the polarization of tumor-associated macrophages and thus promotes cancer progression.

  14. IL-35 Decelerates the Inflammatory Process by Regulating Inflammatory Cytokine Secretion and M1/M2 Macrophage Ratio in Psoriasis.

    PubMed

    Zhang, Junfeng; Lin, Yi; Li, Chunlei; Zhang, Xiaomei; Cheng, Lin; Dai, Lei; Wang, Youcui; Wang, Fangfang; Shi, Gang; Li, Yiming; Yang, Qianmei; Cui, Xueliang; Liu, Yi; Wang, Huiling; Zhang, Shuang; Yang, Yang; Xiang, Rong; Li, Jiong; Yu, Dechao; Wei, Yuquan; Deng, Hongxin

    2016-09-15

    IL-35 downregulates Th17 cell development and suppresses certain types of autoimmune inflammation such as collagen-induced arthritis and experimental autoimmune uveitis. Psoriasis is thought to be initiated by abnormal interactions between cutaneous keratinocytes and systemic immune cells. However, the role of IL-35 in psoriasis remains unclear. In this study, we assessed IL-35 in three well-known psoriasis models: a human keratinocyte cell line (HaCaT), a keratin 14 (K14)-vascular endothelial growth factor A (VEGF-A)-transgenic (Tg) mouse model, and an imiquimod-induced psoriasis mouse model. First, we found that IL-35 suppressed the expression of IL-6, CXCL8, and S100A7, which are highly upregulated by a mixture of five proinflammatory cytokines in HaCaT. Second, a plasmid coding for the human IL-35 sequence coated with cationic liposomes showed potent immunosuppressive effects on K14-VEGF-A-Tg and imiquimod-induced psoriasis mouse models. In the K14-VEGF-A-Tg model, our results showed that several types of proinflammatory cytokines were significantly reduced, whereas IL-10 was remarkably induced by IL-35. Compared with pcDNA3.1, there was a small number of CD4(+)IL-17(+) T cells and a large number of CD4(+)IL-10(+) and CD4(+)CD25(+)Foxp3(+) T cells in the IL-35 group. Most importantly, we found that IL-35 decreased the total number of macrophages and ratio of M1/M2 macrophages, which has not been reported previously. In addition, compared with dexamethasone, IL-35 showed long-term therapeutic efficacy. In summary, our results strongly indicate that IL-35 plays a potent immunosuppressive role in psoriasis. Thus, IL-35 has potential for development as a new therapeutic strategy for patients with chronic psoriasis and other cutaneous inflammatory diseases.

  15. IL-35 Decelerates the Inflammatory Process by Regulating Inflammatory Cytokine Secretion and M1/M2 Macrophage Ratio in Psoriasis.

    PubMed

    Zhang, Junfeng; Lin, Yi; Li, Chunlei; Zhang, Xiaomei; Cheng, Lin; Dai, Lei; Wang, Youcui; Wang, Fangfang; Shi, Gang; Li, Yiming; Yang, Qianmei; Cui, Xueliang; Liu, Yi; Wang, Huiling; Zhang, Shuang; Yang, Yang; Xiang, Rong; Li, Jiong; Yu, Dechao; Wei, Yuquan; Deng, Hongxin

    2016-09-15

    IL-35 downregulates Th17 cell development and suppresses certain types of autoimmune inflammation such as collagen-induced arthritis and experimental autoimmune uveitis. Psoriasis is thought to be initiated by abnormal interactions between cutaneous keratinocytes and systemic immune cells. However, the role of IL-35 in psoriasis remains unclear. In this study, we assessed IL-35 in three well-known psoriasis models: a human keratinocyte cell line (HaCaT), a keratin 14 (K14)-vascular endothelial growth factor A (VEGF-A)-transgenic (Tg) mouse model, and an imiquimod-induced psoriasis mouse model. First, we found that IL-35 suppressed the expression of IL-6, CXCL8, and S100A7, which are highly upregulated by a mixture of five proinflammatory cytokines in HaCaT. Second, a plasmid coding for the human IL-35 sequence coated with cationic liposomes showed potent immunosuppressive effects on K14-VEGF-A-Tg and imiquimod-induced psoriasis mouse models. In the K14-VEGF-A-Tg model, our results showed that several types of proinflammatory cytokines were significantly reduced, whereas IL-10 was remarkably induced by IL-35. Compared with pcDNA3.1, there was a small number of CD4(+)IL-17(+) T cells and a large number of CD4(+)IL-10(+) and CD4(+)CD25(+)Foxp3(+) T cells in the IL-35 group. Most importantly, we found that IL-35 decreased the total number of macrophages and ratio of M1/M2 macrophages, which has not been reported previously. In addition, compared with dexamethasone, IL-35 showed long-term therapeutic efficacy. In summary, our results strongly indicate that IL-35 plays a potent immunosuppressive role in psoriasis. Thus, IL-35 has potential for development as a new therapeutic strategy for patients with chronic psoriasis and other cutaneous inflammatory diseases. PMID:27527600

  16. STAT1 Signaling within Macrophages Is Required for Antifungal Activity against Cryptococcus neoformans

    PubMed Central

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

    2015-01-01

    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. PMID:26351277

  17. 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

  18. [Molecular mechanisms regulating the activity of macrophages].

    PubMed

    Onoprienko, L V

    2011-01-01

    This article reviews modern concepts of the most common types of macrophage activation: classical, alternative, and type II. Molecular mechanisms of induction and regulation of these three types of activation are discussed. Any population of macrophages was shown to change its properties depending on its microenvironment and concrete biological situation (the "functional plasticity of macrophages"). Many intermediate states of macrophages were described along with the most pronounced and well-known activation types (classical activation, alternative activation, and type II activation). These intermediate states are characterized by a variety of combinations of their biological properties, including elements of the three afore mentioned types of activation. Macrophage activity is regulated by a complex network of interrelated cascade mechanisms.

  19. The effect of Lycium barbarum on spinal cord injury, particularly its relationship with M1 and M2 macrophage in rats

    PubMed Central

    2013-01-01

    Background Our past researches suggested that L. barbarum exhibits direct neuroprotective and immune regulatory effects on the central nervous system, which are highly related to the events involved in the spinal cord injury, but not yet been investigated. Immune responses play an important role in the development of the pathology after secondary injury, particularly the M1 and M2 types of macrophage, on which special emphasis was laid in this study. Methods In our previous studies L. barbarum was administrated orally from 7 days before the injury to ensure a stabilized concentration in the blood. For clinical application, L. barbarum can only be administered after the injury. Therefore, both pre-injury and post-injury administration protocols were compared. In vivo and in vitro studies were conducted and analyzed immunohistochemically, including Western blotting. Results The lesion size in the pre-treated group was much larger than that in the post-treated group. To explain this difference, we first studied the effect of L. barbarum on astrocytes, which forms the glial scar encircling the lesion. L. barbarum did not significantly affect the astrocytes. Then we studied the effect of L. barbarum on microglia/macrophages, particularly the M1 and M2 polarization. After spinal cord injury, the deleterious M1 cells dominant the early period, whereas the beneficial M2 cells dominate later. We found that in the pre-treated group L. barbarum significantly enhanced the expression of M1 cells and suppressed that of M2 cells, while in the post-treated group LBP markedly promoted the activity of M2 cells. This explained the difference between the pre- and post-treated groups. Conclusions Lycium barbarum has been wildly accepted to have beneficial effects in various central nervous system diseases. Our finding of deleterious effect of LBP administered at early period of spinal cord injury, indicates that its application should be avoided. The substantial beneficial effect of

  20. 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

  1. Melanoma exosome induction of endothelial cell GM-CSF in pre-metastatic lymph nodes may result in different M1 and M2 macrophage mediated angiogenic processes.

    PubMed

    Hood, Joshua L

    2016-09-01

    Angiogenesis is a key process in the preparation of lymph nodes for melanoma metastasis. Granulocyte macrophage colony stimulating factor (GM-CSF) induces hypoxia inducible factor 1 alpha (HIF-1α) in M1 or HIF-2α in M2 polarized macrophages. HIF-1α promotes neoangiogenesis while HIF-2α facilitates morphogenic normalization of neovasculature. Melanoma exosomes induce GM-CSF expression by endothelial cells in vitro and HIF-1α expression in pre-metastatic lymph nodes in vivo. This suggest a relationship between melanoma exosome induced endothelial GM-CSF and macrophage mediated angiogenesis in lymph nodes. Theoretically, induction of endothelial cell derived GM-CSF by melanoma exosomes mediates different angiogenic functions in pre-metastatic lymph nodes depending on subcapsular sinus (SCS) macrophage polarity. To explore this hypothesis, experiments utilizing melanoma exosomes in a lymph node model are outlined. Despite their opposing immune functions, indirect melanoma exosome stimulation of M1 or M2 SCS macrophages via endothelial derived GM-CSF in lymph nodes may induce different although complementary pro-tumor angiogenic processes. PMID:27515216

  2. Maternal immune activation leads to activated inflammatory macrophages in offspring

    PubMed Central

    Onore, Charity E.; Schwartzer, Jared J.; Careaga, Milo; Bennan, Robert F.; Ashwood, Paul

    2015-01-01

    Several epidemiological studies have shown an association between infection or inflammation during pregnancy and increased risk of autism in the child. In addition, animal models have illustrated that maternal inflammation during gestation can cause autism-relevant behaviors in the offspring; so called maternal immune activation (MIA) models. More recently, permanent changes in T cell cytokine responses were reported in children with autism and in offspring of MIA mice; however, the cytokine responses of other immune cell populations have not been thoroughly investigated in these MIA models. Similar to changes in T cell function, we hypothesized that following MIA, offspring will have long-term changes in macrophage function. To test this theory, we utilized the poly (I:C) MIA mouse model in C57BL/6J mice and examined macrophage cytokine production in adult offspring. Pregnant dams were given either a single injection of 20 mg/kg polyinosinic–polycytidylic acid, poly (I:C), or saline delivered intraperitoneally on gestational day 12.5. When offspring of poly (I:C) treated dams reached 10 weeks of age, femurs were collected and bone marrow-derived macrophages were generated. Cytokine production was measured in bone marrow-derived macrophages incubated for 24 h in either growth media alone, LPS, IL-4/LPS, or IFN-γ/LPS. Following stimulation with LPS alone, or the combination of IFN-γ/LPS, macrophages from offspring of poly (I:C) treated dams produced higher levels of IL-12(p40) (p < 0.04) suggesting an increased M1 polarization. In addition, even without the presence of a polarizing cytokine or LPS stimulus, macrophages from offspring of poly (I:C) treated dams exhibited a higher production of CCL3 (p = 0.05). Moreover, CCL3 levels were further increased when stimulated with LPS, or polarized with either IL-4/LPS or IFN-γ/LPS (p < 0.05) suggesting a general increase in production of this chemokine. Collectively, these data suggest that MIA can produce lasting

  3. Purinergic signaling during macrophage differentiation results in M2 alternative activated macrophages.

    PubMed

    Barberà-Cremades, Maria; Baroja-Mazo, Alberto; Pelegrín, Pablo

    2016-02-01

    Macrophages represent a highly heterogenic cell population of the innate immune system, with important roles in the initiation and resolution of the inflammatory response. Purinergic signaling regulates both M1 and M2 macrophage function at different levels by controlling the secretion of cytokines, phagocytosis, and the production of reactive oxygen species. We found that extracellular nucleotides arrest macrophage differentiation from bone marrow precursors via adenosine and P2 receptors. This results in a mature macrophage with increased expression of M2, but not M1, genes. Similar to adenosine and ATP, macrophage growth arrested with LPS treatment resulted in an increase of the M2-related marker Ym1. Recombinant Ym1 was able to affect macrophage proliferation and could, potentially, be involved in the arrest of macrophage growth during hematopoiesis.

  4. 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).

  5. 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

    2015-01-01

    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). PMID:26287131

  6. EPA protects against muscle damage in the mdx mouse model of Duchenne muscular dystrophy by promoting a shift from the M1 to M2 macrophage phenotype.

    PubMed

    Carvalho, Samara Camaçari de; Apolinário, Leticia Montanholi; Matheus, Selma Maria Michelin; Santo Neto, Humberto; Marques, Maria Julia

    2013-11-15

    In dystrophic mdx mice and in Duchenne muscular dystrophy, inflammation contributes to myonecrosis. Previously, we demonstrated that eicosapentaenoic acid (EPA) decreased inflammation and necrosis in dystrophic muscle. In the present study, we examined the effects of EPA and the corticoid deflazacort (DFZ) as modulators of M1 (iNOS-expressing cells) and M2 (CD206-expressing cells) macrophages. Mdx mice (14 days old) received EPA or DFZ for 16 days. The diaphragm, biceps brachii and quadriceps muscles were studied. Immunofluorescence, immunoblotting and ELISA assays showed that EPA increased interleucin-10, reduced interferon-γ and was more effective than DFZ in promoting a shift from M1 to M2.

  7. The Role of M1 and M2 Macrophages in Prostate Cancer in relation to Extracapsular Tumor Extension and Biochemical Recurrence after Radical Prostatectomy

    PubMed Central

    Lanciotti, M.; Masieri, L.; Raspollini, M. R.; Minervini, A.; Mari, A.; Comito, G.; Giannoni, E.; Carini, M.; Chiarugi, P.; Serni, S.

    2014-01-01

    Introduction. The aim of our work was to investigate the causal connection between M1 and M2 macrophage phenotypes occurrence and prostate cancer, their correlation with tumor extension (ECE), and biochemical recurrence (BR). Patient and Methods. Clinical and pathological data were prospectively gathered from 93 patients treated with radical prostatectomy. Correlations of commonly used variables were evaluated with uni- and multivariate analysis. The relationship between M1 and M2 occurrence and BR was also assessed with Kaplan-Meier survival analysis. Results. Above all in 63.4% there was a M2 prevalence. M1 occurred more frequently in OC disease, while M2 was more represented in ECE. At univariate analysis biopsy and pathologic GS and M2 were statistically correlated with ECE. Only pathologic GS and M2 confirmed to be correlated with ECE. According to macrophage density BCR free survival curves presented a statistically significant difference. When we stratified our population for M1 and M2,we did not find any statistical difference among curves. At univariate analysis GS, pTNM, and positive margins resulted to be significant predictors of BCR, while M1 and M2 did not achieve the statistical significance. At multivariate analysis, only GS and pathologic stage were independent predictors of BR. Conclusion. In our study patients with higher density of M count were associated with poor prognosis; M2 phenotype was significantly associated with ECE. PMID:24738060

  8. 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

  9. 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

  10. High salt reduces the activation of IL-4- and IL-13-stimulated macrophages.

    PubMed

    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

    2015-11-01

    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.

  11. 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

  12. Activation of Muscarinic M1 Acetylcholine Receptors Induces Long-Term Potentiation in the Hippocampus.

    PubMed

    Dennis, Siobhan H; Pasqui, Francesca; Colvin, Ellen M; Sanger, Helen; Mogg, Adrian J; Felder, Christian C; Broad, Lisa M; Fitzjohn, Steve M; Isaac, John T R; Mellor, Jack R

    2016-01-01

    Muscarinic M1 acetylcholine receptors (M1Rs) are highly expressed in the hippocampus, and their inhibition or ablation disrupts the encoding of spatial memory. It has been hypothesized that the principal mechanism by which M1Rs influence spatial memory is by the regulation of hippocampal synaptic plasticity. Here, we use a combination of recently developed, well characterized, selective M1R agonists and M1R knock-out mice to define the roles of M1Rs in the regulation of hippocampal neuronal and synaptic function. We confirm that M1R activation increases input resistance and depolarizes hippocampal CA1 pyramidal neurons and show that this profoundly increases excitatory postsynaptic potential-spike coupling. Consistent with a critical role for M1Rs in synaptic plasticity, we now show that M1R activation produces a robust potentiation of glutamatergic synaptic transmission onto CA1 pyramidal neurons that has all the hallmarks of long-term potentiation (LTP): The potentiation requires NMDA receptor activity and bi-directionally occludes with synaptically induced LTP. Thus, we describe synergistic mechanisms by which acetylcholine acting through M1Rs excites CA1 pyramidal neurons and induces LTP, to profoundly increase activation of CA1 pyramidal neurons. These features are predicted to make a major contribution to the pro-cognitive effects of cholinergic transmission in rodents and humans. PMID:26472558

  13. Monocytes and macrophages, implications for breast cancer migration and stem cell-like activity and treatment

    PubMed Central

    Ward, Rebecca; Sims, Andrew H.; Lee, Alexander; Lo, Christina; Wynne, Luke; Yusuf, Humza; Gregson, Hannah; Lisanti, Michael P.; Sotgia, Federica; Landberg, Göran; Lamb, Rebecca

    2015-01-01

    Macrophages are a major cellular constituent of the tumour stroma and contribute to breast cancer prognosis. The precise role and treatment strategies to target macrophages remain elusive. As macrophage infiltration is associated with poor prognosis and high grade tumours we used the THP-1 cell line to model monocyte-macrophage differentiation in co-culture with four breast cancer cell lines (MCF7, T47D, MDA-MB-231, MDA-MB-468) to model in vivo cellular interactions. Polarisation into M1 and M2 subtypes was confirmed by specific cell marker expression of ROS and HLA-DR, respectively. Co-culture with all types of macrophage increased migration of ER-positive breast cancer cell lines, while M2-macrophages increased mammosphere formation, compared to M1-macrophages, in all breast cancer cells lines. Treatment of cells with Zoledronate in co-culture reduced the “pro-tumourigenic” effects (increased mammospheres/migration) exerted by macrophages. Direct treatment of breast cancer cells in homotypic culture was unable to reduce migration or mammosphere formation. Macrophages promote “pro-tumourigenic” cellular characteristics of breast cancer cell migration and stem cell activity. Zoledronate targets macrophages within the microenvironment which in turn, reduces the “pro-tumourigenic” characteristics of breast cancer cells. Zoledronate offers an exciting new treatment strategy for both primary and metastatic breast cancer. PMID:26008983

  14. 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.

  15. Statin Attenuates Experimental Anti-Glomerular Basement Membrane Glomerulonephritis Together with the Augmentation of Alternatively Activated Macrophages

    PubMed Central

    Fujita, Emiko; Shimizu, Akira; Masuda, Yukinari; Kuwahara, Naomi; Arai, Takashi; Nagasaka, Shinya; Aki, Kaoru; Mii, Akiko; Natori, Yasuhiro; Iino, Yasuhiko; Katayama, Yasuo; Fukuda, Yuh

    2010-01-01

    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-γ, tumor necrosis factor-α, 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. PMID:20696778

  16. In vitro dissection of the membrane and RNP binding activities of influenza virus M1 protein.

    PubMed

    Baudin, F; Petit, I; Weissenhorn, W; Ruigrok, R W

    2001-03-01

    Spontaneous proteolysis of influenza virus M1 protein during crystallisation has defined an N-terminal domain of amino acids 1--164. Full-length M1, the N-terminal domain, and the C-terminal part of M1 (residues 165--252) were produced in Escherichia coli. In vitro tests showed that only full-length M1 and its N-terminal domain bind to negatively charged liposomes and that only full-length M1 and its C-terminal part bind to RNP. However, only full-length M1 had transcription inhibition activity. Several independent experimental approaches indicate that in vitro transcription inhibition occurs through polymerisation/aggregation of M1 onto RNP, or of M1 onto M1 already bound to RNP, rather than by binding to a specific active site on the nucleoprotein or the polymerase. The structure/function of influenza virus M1 will be compared with that of the Ebola virus matrix protein, VP40. PMID:11222100

  17. PI3K/Akt Signaling Pathway Modulates Influenza Virus Induced Mouse Alveolar Macrophage Polarization to M1/M2b

    PubMed Central

    Zhao, Xiangfeng; Dai, Jianping; Xiao, Xuejun; Wu, Liqi; Zeng, Jun; Sheng, Jiangtao; Su, Jinghua; Chen, Xiaoxuan; Wang, Gefei; Li, Kangsheng

    2014-01-01

    Macrophages polarized to M1 (pro-inflammation) or M2 (anti-inflammation) phenotypes in response to environmental signals. In this study, we examined the polarization of alveolar macrophage (AM), following induction by different influenza virus strains (ST169 (H1N1), ST602 (H3N2) and HKG9 (H9N2)). Macrophages from other tissues or cell line exert alternative responding pattern, and AM is necessary for investigating the respiratory system. AM polarized toward the M1 phenotype after 4 hours of infection by all three virus strains, and AM to presented M2b phenotype after 8 hours induction, and immunosuppressive phenotype after 24 hours of induction. Protein expression assay showed similar results as the gene expression analysis for phenotype verification. The ELISA assay showed that TNF-α secretion was up-regulated after 4 and 8 hours of infection by influenza viruses, and it returned to basal levels after 24 hours of infection. IL-10 expression was elevated after 8 and 24 hours of infection. Immunofluorescence showed that iNOS expression was up-regulated but not Arg1 expression. Influenza virus notably increased phospho-Akt but not phospho-Erk1/2 or phospho-p38, and the AM polarization pattern have been changed by LY294002 (PI3K inhibitor). In conclusion, our results demonstrate the dynamic polarization of AM induced by influenza viruses, and suggested that PI3K/Akt signaling pathway modulates AM polarization to M1/M2b. PMID:25105760

  18. 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

  19. Extended Practice of a Motor Skill Is Associated with Reduced Metabolic Activity in M1

    PubMed Central

    PICARD, NATHALIE; MATSUZAKA, YOSHIYA; STRICK, PETER L.

    2013-01-01

    How does long-term training and the development of motor skill modify the activity of the primary motor cortex (M1)? To address this issue we trained monkeys for ~1–6 years to perform visually-guided and internally-generated sequences of reaching movements. Then, we used 14C-2-deoxyglucose (2DG) uptake and single neuron recording to measure metabolic and neuron activity in M1. After extended practice, we observed a profound reduction of metabolic activity in M1 for the performance of internally-generated compared to visually-guided tasks. In contrast, measures of neuron firing displayed little difference during the two tasks. These findings suggest that the development of skill through extended practice results in a reduction in the synaptic activity required to produce internally-generated, but not visually-guided sequences of movements. Thus, practice leading to skilled performance results in more efficient generation of neuronal activity in M1. PMID:23912947

  20. Mangiferin inhibits macrophage classical activation via downregulating interferon regulatory factor 5 expression.

    PubMed

    Wei, Zhiquan; Yan, Li; Chen, Yixin; Bao, Chuanhong; Deng, Jing; Deng, Jiagang

    2016-08-01

    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

  1. 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

  2. Critical illness induces alternative activation of M2 macrophages in adipose tissue

    PubMed Central

    2011-01-01

    Introduction We recently reported macrophage accumulation in adipose tissue of critically ill patients. Classically activated macrophage accumulation in adipose tissue is a known feature of obesity, where it is linked with increasing insulin resistance. However, the characteristics of adipose tissue macrophage accumulation in critical illness remain unknown. Methods We studied macrophage markers with immunostaining and gene expression in visceral and subcutaneous adipose tissue from healthy control subjects (n = 20) and non-surviving prolonged critically ill patients (n = 61). For comparison, also subcutaneous in vivo adipose tissue biopsies were studied from 15 prolonged critically ill patients. Results Subcutaneous and visceral adipose tissue biopsies from non-surviving prolonged critically ill patients displayed a large increase in macrophage staining. This staining corresponded with elevated gene expression of "alternatively activated" M2 macrophage markers arginase-1, IL-10 and CD163 and low levels of the "classically activated" M1 macrophage markers tumor necrosis factor (TNF)-α and inducible nitric-oxide synthase (iNOS). Immunostaining for CD163 confirmed positive M2 macrophage staining in both visceral and subcutaneous adipose tissue biopsies from critically ill patients. Surprisingly, circulating levels and tissue gene expression of the alternative M2 activators IL-4 and IL-13 were low and not different from controls. In contrast, adipose tissue protein levels of peroxisome proliferator-activated receptor-γ (PPARγ), a nuclear receptor required for M2 differentiation and acting downstream of IL-4, was markedly elevated in illness. In subcutaneous abdominal adipose tissue biopsies from surviving critically ill patients, we could confirm positive macrophage staining with CD68 and CD163. We also could confirm elevated arginase-1 gene expression and elevated PPARγ protein levels. Conclusions Unlike obesity, critical illness evokes adipose tissue

  3. Cholesteryl ester hydrolase activity is abolished in HSL-/- macrophages but unchanged in macrophages lacking KIAA1363.

    PubMed

    Buchebner, Marlene; Pfeifer, Thomas; Rathke, Nora; Chandak, Prakash G; Lass, Achim; Schreiber, Renate; Kratzer, Adelheid; Zimmermann, Robert; Sattler, Wolfgang; Koefeler, Harald; Fröhlich, Eleonore; Kostner, Gerhard M; Birner-Gruenberger, Ruth; Chiang, Kyle P; Haemmerle, Guenter; Zechner, Rudolf; Levak-Frank, Sanja; Cravatt, Benjamin; Kratky, Dagmar

    2010-10-01

    Cholesteryl ester (CE) accumulation in macrophages represents a crucial event during foam cell formation, a hallmark of atherogenesis. Here we investigated the role of two previously described CE hydrolases, hormone-sensitive lipase (HSL) and KIAA1363, in macrophage CE hydrolysis. HSL and KIAA1363 exhibited marked differences in their abilities to hydrolyze CE, triacylglycerol (TG), diacylglycerol (DG), and 2-acetyl monoalkylglycerol ether (AcMAGE), a precursor for biosynthesis of platelet-activating factor (PAF). HSL efficiently cleaved all four substrates, whereas KIAA1363 hydrolyzed only AcMAGE. This contradicts previous studies suggesting that KIAA1363 is a neutral CE hydrolase. Macrophages of KIAA1363(-/-) and wild-type mice exhibited identical neutral CE hydrolase activity, which was almost abolished in tissues and macrophages of HSL(-/-) mice. Conversely, AcMAGE hydrolase activity was diminished in macrophages and some tissues of KIAA1363(-/-) but unchanged in HSL(-/-) mice. CE turnover was unaffected in macrophages lacking KIAA1363 and HSL, whereas cAMP-dependent cholesterol efflux was influenced by HSL but not by KIAA1363. Despite decreased CE hydrolase activities, HSL(-/-) macrophages exhibited CE accumulation similar to wild-type (WT) macrophages. We conclude that additional enzymes must exist that cooperate with HSL to regulate CE levels in macrophages. KIAA1363 affects AcMAGE hydrolase activity but is of minor importance as a direct CE hydrolase in macrophages.

  4. MMP-10 Regulates Collagenolytic Activity of Alternatively Activated Resident Macrophages

    PubMed Central

    Rohani, Maryam G.; McMahan, Ryan S.; Razumova, Maria V.; Hertz, Angie L.; Cieslewicz, Maryelise; Pun, Suzie H.; Regnier, Michael; Wang, Ying; Birkland, Timothy P.; Parks, William C.

    2015-01-01

    MMP-10 is expressed by macrophages and epithelium in response to injury, but its functions in wound repair are unknown. We observed increased collagen deposition and skin stiffness in Mmp10−/− wounds with no difference in collagen expression or re-epithelialization. Increased collagen deposition in Mmp10−/− wounds was accompanied by less collagenolytic activity and reduced expression of specific metallocollagenases, particularly MMP-8 and MMP-13, where MMP-13 was the key collagenase. Ablation and adoptive transfer approaches and cell-based models demonstrated that the MMP-10-dependent collagenolytic activity was a product of alternatively activated (M2) resident macrophages. These data demonstrate a critical role for macrophage MMP-10 in controlling the tissue remodeling activity of macrophages and moderating scar formation during wound repair. PMID:25927164

  5. Macrophage activation and its role in repair and pathology after spinal cord injury.

    PubMed

    Gensel, John C; Zhang, Bei

    2015-09-01

    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.

  6. MiR-16 regulates mouse peritoneal macrophage polarization and affects T-cell activation.

    PubMed

    Jia, Xiaoqin; Li, Xiaomin; Shen, Yating; Miao, Junjun; Liu, Hao; Li, Guoli; Wang, Zhengbing

    2016-10-01

    MiR-16 is a tumour suppressor that is down-regulated in certain human cancers. However, little is known on its activity in other cell types. In this study, we examined the biological significance and underlying mechanisms of miR-16 on macrophage polarization and subsequent T-cell activation. Mouse peritoneal macrophages were isolated and induced to undergo either M1 polarization with 100 ng/ml of interferon-γ and 20 ng/ml of lipopolysaccharide, or M2 polarization with 20 ng/ml of interleukin (IL)-4. The identity of polarized macrophages was determined by profiling cell-surface markers by flow cytometry and cytokine production by ELISA. Macrophages were infected with lentivirus-expressing miR-16 to assess the effects of miR-16. Effects on macrophage-T cell interactions were analysed by co-culturing purified CD4(+) T cells with miR-16-expressing peritoneal macrophages, and measuring activation marker CD69 by flow cytometry and cytokine secretion by ELISA. Bioinformatics analysis was applied to search for potential miR-16 targets and understand its underlying mechanisms. MiR-16-induced M1 differentiation of mouse peritoneal macrophages from either the basal M0- or M2-polarized state is indicated by the significant up-regulation of M1 marker CD16/32, repression of M2 marker CD206 and Dectin-1, and increased secretion of M1 cytokine IL-12 and nitric oxide. Consistently, miR-16-expressing macrophages stimulate the activation of purified CD4(+) T cells. Mechanistically, miR-16 significantly down-regulates the expression of PD-L1, a critical immune suppressor that controls macrophage-T cell interaction and T-cell activation. MiR-16 plays an important role in shifting macrophage polarization from M2 to M1 status, and functionally activating CD4(+) T cells. This effect is potentially mediated through the down-regulation of immune suppressor PD-L1.

  7. Vocal Fold Fibroblasts Immunoregulate Activated Macrophage Phenotype

    PubMed Central

    King, Suzanne N.; Chen, Fei; Jetté, Marie E.; Thibeault, Susan L.

    2012-01-01

    Recent evidence suggests that fibroblasts play a critical role in regulating inflammation during wound healing because they express several inflammatory mediators in response to bacteria. The objective of this study was to analyze the effects of lipopolysaccaride (LPS) on the immunomodulatory properties of vocal fold fibroblasts (VFF) derived from polyps, scar and normal tissue co-cultured with macrophages, to provide insight into their interactions during the inflammatory process. Fibroblasts were co-cultured with CD14+ monocytes and after 7 days, wells were treated with LPS for 24 and 72 hours. Culture supernatants were collected and concentrations of TNF-α, IL-6, IL-8, IL-10, IL-12, IL-1β, and MCP-1 were quantified by ELISA. Normal VFF and CD14+ monocultures were used as controls. Twenty-four hours after LPS activation, macrophages co-cultured with polyp VFF had significantly increased expression of TNF-α, IL-1β, IL-12, and IL-10 compared to controls (p<0.0001). In contrast, macrophages co-cultured with scar VFF had significantly lower expression of TNF-α, IL-1β and IL-12 with significantly higher IL-10 compared to control (p<0.0001). After 72 hours, macrophages co-cultured with polyp VFF increased expression of TNF-α, IL-1β, IL-10, IL-6, IL-8, MCP-1 and TGF-β (p<0.01) and macrophages co-cultured with scar VFF significantly decreased their expression of IL-1β and IL-12 compared to control (p<0.0001). Scar VFF at both time points produced significantly lower levels of IL-8, MCP-1, IL-6 and TGF-β compared to controls (p<0.05). Based on our findings, VFF and macrophages secrete several inflammatory mediators that modify their diverse functions. Polyp and scar VFF may play a role in regulating abnormal inflammatory responses, which could result in excessive ECM deposition that disrupts the function of the vocal folds. PMID:23123198

  8. Mouse macrophage polarity and ROCK1 activity depend on RhoA and non-apoptotic Caspase 3.

    PubMed

    Liu, Yianzhu; Minze, Laurie J; Mumma, Lindsay; Li, Xian C; Ghobrial, Rafik M; Kloc, Malgorzata

    2016-02-15

    The macrophages have different subtypes with different functions in immune response and disease. It has been generally accepted that M1 macrophages are responsible for stimulation of immune system and inflammation while M2 macrophages play a role in tissue repair. Irrespective of the type, macrophage functions depend on actin cytoskeleton, which is under the control of small GTPase RhoA pathway and its downstream effector ROCK1. We generated RhoA-deleted macrophages and compared the effect of RhoA deletion on M0, M1 and M2 macrophage phenotype. Our studies showed that, unexpectedly, the RhoA deletion did not eliminate macrophage ROCK1 expression and increased ROCK1 activity. The RhoA deletion effect on macrophage phenotype, structure and polarity was different for each subtype. Moreover, our study indicates that the up-regulation of ROCK1 activity in RhoA-deleted macrophages and macrophage phenotype/polarity are dependent on non-apoptotic Caspase-3 and are sensitive to Caspase-3 inhibition. These novel findings will revise/complement our understanding of RhoA pathway regulation of cell structure and polarity. PMID:26875770

  9. 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.

  10. 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.

  11. Activation of mesenchymal stem cells by macrophages promotes tumor progression through immune suppressive effects

    PubMed Central

    Jia, Xiao-hua; Feng, Guo-wei; Wang, Zhong-liang; Du, Yang; Shen, Chen; Hui, Hui; Peng, Dong; Li, Zong-jin; Kong, De-ling; Tian, Jie

    2016-01-01

    Cancer development and progression is linked to tumor-associated macrophages (TAMs). Distinct TAMs subsets perform either protective or pathogenic effects in cancer. A protective role in carcinogenesis has been described for M1 macrophages, which activate antitumor mechanisms. By comparison, TAMs isolated from solid and metastatic tumors have a suppressive M2-like phenotype, which could support multiple aspects of tumor progression. Currently, it has not been clearly understood how macrophages in tumor-associated stroma could be hijacked to support tumor growth. Mesenchymal stem cells (MSCs) actively interact with components of the innate immune system and display both anti-inflammatory and pro-inflammatory effects. Here, we tested whether MSCs could favor the tumor to escape from immunologic surveillance in the presence of M1 macrophages. We found that MSCs educated by M1 condition medium (cMSCs) possessed a greatly enhanced ability in promoting tumor growth in vivo. Examination of cytokines/chemokines showed that the cMSCs acquired a regulatory profile, which expressed high levels of iNOS and MCP1. Consistent with an elevated MCP1 expression in cMSCs, the tumor-promoting effect of the cMSCs depended on MCP1 mediated macrophage recruitment to tumor sites. Furthermore, IL-6 secreted by the cMSCs could polarize infiltrated TAMs into M2-like macrophages. Therefore, when macrophages changed into M1 pro-inflammation type in tumor microenvironment, the MSCs would act as poor sensors and switchers to accelerate tumor growth. PMID:26988913

  12. Cytolytic activity against tumor cells by macrophage cell lines and augmentation by macrophage stimulants.

    PubMed

    Taniyama, T; Holden, H T

    1980-07-15

    Previous studies have shown that macrophage cell lines retained the ability to phagocytize, to secrete lysosomal enzymes, and to function as effector cells in antibody-dependent cellular cytoxicity. In this paper, the cytolytic activity of murine macrophage cell lines against tumor target cells was assessed using an 18-h 51Cr release assay. Of the macrophage cell lines tested, RAW 264, PU5-1.8 and IC-21 had intermediate to high levels of spontaneous cytolytic activity, P388D, and J774 had low to intermediate levels, while /WEHI-3 showed little or no cytolytic activity against RBL-5, MBL-2 and TU-5 target cells. Tumor-cell killing by macrophage cell lines could be augmented by the addition of macrophage stimulants, such as bacterial lipopolysaccharide and poly I:C, indicating that the activation of macrophages by these stimulants does not require the participation of other cell types. Treatment with interferon also augmented the tumor-cell killing by macrophage cell lines. Although the mechanism by which these cell lines exert their spontaneous or boosted cytotoxic activity is not clear, it does not appear to be due to depletion of nutrients since cell lines with high metabolic and proliferative activities, such as WEHI-3 and RBL-5, showed little or no cytotoxicity and supernatants from the macrophage cell lines did not exert any cytotoxic effects in their essay. Thus, it appears that the different macrophage cell lines represent different levels of activation and/or differentiation and may be useful for studying the development of these processes as well as providing a useful tool for analyzing the mechanisms of macrophage-mediated cytolysis. PMID:6165690

  13. 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.

  14. Adipose tissue macrophages in insulin-resistant subjects are associated with collagen VI and fibrosis and demonstrate alternative activation.

    PubMed

    Spencer, Michael; Yao-Borengasser, Aiwei; Unal, Resat; Rasouli, Neda; Gurley, Catherine M; Zhu, Beibei; Peterson, Charlotte A; Kern, Philip A

    2010-12-01

    Adipose tissue macrophages are associated with insulin resistance and are linked to changes in the extracellular matrix. To better characterize adipose macrophages, the extracellular matrix, and adipocyte-macrophage interactions, gene expression from adipose tissue and the stromal vascular fraction was assessed for markers of inflammation and fibrosis, and macrophages from obese and lean subjects were counted and characterized immunohistochemically. Coculture experiments examined the effects of adipocyte-macrophage interaction. Collagen VI gene expression was associated with insulin sensitivity and CD68 (r = -0.56 and 0.60, P < 0.0001) and with other markers of inflammation and fibrosis. Compared with adipose tissue from lean subjects, adipose tissue from obese subjects contained increased areas of fibrosis, which correlated inversely with insulin sensitivity (r = -0.58, P < 0.02) and positively with macrophage number (r = 0.70, P < 0.01). Although macrophages in crownlike structures (CLS) were more abundant in obese adipose tissue, the majority of macrophages were associated with fibrosis and were not organized in CLS. Macrophages in CLS were predominantly M1, but most other macrophages, particularly those in fibrotic areas, were M2 and also expressed CD150, a marker of M2c macrophages. Coculture of THP-1 macrophages with adipocytes promoted the M2 phenotype, with a lower level of IL-1 expression and a higher ratio of IL-10 to IL-12. Transforming growth factor-β (TGF-β) was more abundant in M2 macrophages and was further increased by coculture with adipocytes. Downstream effectors of TGF-β, such as plasminogen activator inhibitor-1, collagen VI, and phosphorylated Smad, were increased in macrophages and adipocytes. Thus adipose tissue of insulin-resistant humans demonstrated increased fibrosis, M2 macrophage abundance, and TGF-β activity.

  15. Molecular imaging of macrophage enzyme activity in cardiac inflammation

    PubMed Central

    Ali, Muhammad; Pulli, Benjamin; Chen, John W.

    2014-01-01

    Molecular imaging is highly advantageous as various insidious inflammatory events can be imaged in a serial and quantitative fashion. Combined with the conventional imaging modalities like computed tomography (CT), magnetic resonance (MR) and nuclear imaging, it helps us resolve the extent of ongoing pathology, quantify inflammation and predict outcome. Macrophages are increasingly gaining importance as an imaging biomarker in inflammatory cardiovascular diseases. Macrophages, recruited to the site of injury, internalize necrotic or foreign material. Along with phagocytosis, activated macrophages release proteolytic enzymes like matrix metalloproteinases (MMPs) and cathepsins into the extracellular environment. Pro-inflammatory monocytes and macrophages also induce tissue oxidative damage through the inflammatory enzyme myeloperoxidase (MPO). In this review we will highlight recent advances in molecular macrophage imaging. Particular stress will be given to macrophage functional and enzymatic activity imaging which targets phagocytosis, proteolysis and myeloperoxidase activity imaging. PMID:24729833

  16. AKT mediated glycolytic shift regulates autophagy in classically activated macrophages.

    PubMed

    Matta, Sumit Kumar; Kumar, Dhiraj

    2015-09-01

    Autophagy is considered as an innate defense mechanism primarily due to its role in the targeting of intracellular pathogens for lysosomal degradation. Here we report inhibition of autophagy as an adaptive response in classically activated macrophages that helps achieve high cellular ROS production and cell death-another hallmark of innate mechanisms. We show prolonged classical activation of Raw 264.7 macrophages by treating them with IFN-γ and LPS inhibited autophagy. The inhibition of autophagy was dependent on nitric oxide (NO) production which activated the AKT-mTOR signaling, the known negative regulators of autophagy. Autophagy inhibition in these cells was accompanied with a shift to aerobic glycolysis along with a decline in the mitochondrial membrane potential (MOMP). The decline in MOMP coupled with autophagy inhibition led to increased mitochondrial content and considerably elevated cellular ROS, eventually causing cell death. Next, using specific siRNA mediated knockdowns we show AKT was responsible for the glycolytic shift and autophagy inhibition in activated macrophages. Surprisingly, AKT knockdown in activated macrophages also rescued them from cell death. Finally we show that AKT mediated autophagy inhibition in the activated macrophages correlated with the depletion of glucose from the extracellular medium, and glucose supplementation not only rescued autophagy levels and reversed other phenotypes of activated macrophages, but also inhibited cell death. Thus we report here a novel link between AKT mediated glycolytic metabolism and autophagy in the activated macrophages, and provide a possible mechanism for sustained macrophage activation in vivo.

  17. Lysophosphatidylcholine perpetuates macrophage polarization toward classically activated phenotype in inflammation.

    PubMed

    Qin, Xiaofei; Qiu, Chunguang; Zhao, Luosha

    2014-01-01

    Pro-inflammatory macrophages are involved in vascular inflammation and serve as the major effector cells in the pathophysiology of atherosclerosis. Phosphatidylcholine (PC) is a major phospholipid moiety affixed to oxidized low-density lipoprotein (oxLDL) and thought to play important roles in the development of atherosclerosis. In this study we described that a bioactive lipid derivative, lysophosphatidylcholine (lysoPC), generated from hydrolysis of the PC moiety of oxidized LDL, promoted and stabilized a strong M1 phenotype in macrophage polarization. Another derivative, 9-hydroxyoctadecadienoic acid (9-HODE), did not show the similar biological function. Blockade of G protein coupled receptor, G2A, which mediates the signal transduction of lysoPC, diminished the effects of lysoPC on the macrophage polarization toward M1 phenotype. The results provide insights into the new mechanism on how oxidized LDL participates in tissue inflammation in atherosclerosis. PMID:24841857

  18. Whole-cell MALDI-TOF MS: a new tool to assess the multifaceted activation of macrophages.

    PubMed

    Ouedraogo, Richard; Daumas, Aurélie; Ghigo, Eric; Capo, Christian; Mege, Jean-Louis; Textoris, Julien

    2012-10-22

    Whole-cell MALDI-TOF MS is routinely used to identify bacterial species in clinical samples. This technique has also proven to allow identification of intact mammalian cells, including macrophages. Here, we wondered whether this approach enabled the assessment human macrophages plasticity. The whole-cell MALDI-TOF spectra of macrophages stimulated with IFN-γ and IL-4, two inducers of M1 and M2 macrophage polarisation, consisted of peaks ranging from 2 to 12 kDa. The spectra of unstimulated and stimulated macrophages were clearly different. The fingerprints induced by the M1 agonists, IFN-γ, TNF, LPS and LPS+IFN-γ, and the M2 agonists, IL-4, TGF-β1 and IL-10, were specific and readily identifiable. Thus, whole-cell MALDI-TOF MS was able to characterise M1 and M2 macrophage subtypes. In addition, the fingerprints induced by extracellular (group B Streptococcus, Staphylococcus aureus) or intracellular (BCG, Orientia tsutsugamushi, Coxiella burnetii) bacteria were bacterium-specific. The whole-cell MALDI-TOF MS fingerprints therefore revealed the multifaceted activation of human macrophages. This approach opened a new avenue of studies to assess the immune response in the clinical setting, by monitoring the various activation patterns of immune cells in pathological conditions.

  19. 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

  20. Alpha-D-galactosylation of surface fucoglycoconjugate(s) upon stimulation/activation of murine peritoneal macrophages.

    PubMed

    Petryniak, J

    1992-04-01

    Murine resident macrophages express, on their surface, carbohydrate epitopes which undergo changes during their stimulation/activation as monitored by binding of 125I labelled Evonymus europaea and Griffonia simplicifolia I-B4 lectins. Treatment of the stimulated macrophages with coffee bean alpha-galactosidase abolished binding of the GS I-B4 isolectin and changed the binding pattern of the Evonymus lectin. The affinity (Ka) of Evonymus lectin for alpha-galactosidase-treated macrophages decreased approximately 23-fold, from 1.25 x 10(8) M-1 to 5.5 x 10(6) M-1. Subsequent digestion of alpha-galactosidase-treated macrophages with alpha-L-fucosidase from Trichomonas foetus, further reduced binding of Evonymus lectin. Resident macrophages showed the same pattern of Evonymus lectin binding, with the same affinity, as alpha-galactosidase-treated, stimulated macrophages. These results, together with a consideration of the carbohydrate binding specificity of the Evonymus lectin which, in the absence of alpha-D-galactosyl groups, requires alpha-L-fucosyl groups for binding, indicate the presence, on resident macrophages, of glycoconjugates with terminal alpha-L-fucosyl residues. It is also concluded that during macrophage stimulation/activation alpha-D-galactosyl residues are added to this glycoconjugate and that they form part of the receptor for Evonymus lectin. The same glycoconjugate(s) is/are also expressed on the activated macrophage IC-21 cell line which exhibits the same characteristics as that of stimulated peritoneal macrophages, i.e., it contains alpha-D-galactosyl end groups and is resistant to the action of trypsin. Both lectins were also specifically bound to Corynaebacterium parvum activated macrophages. PMID:1344714

  1. 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

  2. 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

    2015-12-01

    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.

  3. Suppression of microRNA activity amplifies IFN-γ-induced macrophage activation and promotes anti-tumour immunity.

    PubMed

    Baer, Caroline; Squadrito, Mario Leonardo; Laoui, Damya; Thompson, Danielle; Hansen, Sarah K; Kiialainen, Anna; Hoves, Sabine; Ries, Carola H; Ooi, Chia-Huey; De Palma, Michele

    2016-07-01

    Tumour-associated macrophages (TAMs) largely express an alternatively activated (or M2) phenotype, which entails immunosuppressive and tumour-promoting capabilities. Reprogramming TAMs towards a classically activated (M1) phenotype may thwart tumour-associated immunosuppression and unleash anti-tumour immunity. Here we show that conditional deletion of the microRNA (miRNA)-processing enzyme DICER in macrophages prompts M1-like TAM programming, characterized by hyperactive IFN-γ/STAT1 signalling. This rewiring abated the immunosuppressive capacity of TAMs and fostered the recruitment of activated cytotoxic T lymphocytes (CTLs) to the tumours. CTL-derived IFN-γ exacerbated M1 polarization of Dicer1-deficient TAMs and inhibited tumour growth. Remarkably, DICER deficiency in TAMs negated the anti-tumoral effects of macrophage depletion by anti-CSF1R antibodies, and enabled complete tumour eradication by PD1 checkpoint blockade or CD40 agonistic antibodies. Finally, genetic rescue of Let-7 miRNA activity in Dicer1-deficient TAMs partly restored their M2-like phenotype and decreased tumour-infiltrating CTLs. These findings suggest that DICER/Let-7 activity opposes IFN-γ-induced, immunostimulatory M1-like TAM activation, with potential therapeutic implications. PMID:27295554

  4. 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. PMID:27261736

  5. 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.

  6. 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.

  7. 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. PMID:27482886

  8. Cellular metabolism and macrophage functional polarization.

    PubMed

    Zhu, Linnan; Zhao, Qingjie; Yang, Tao; Ding, Wenjun; Zhao, Yong

    2015-01-01

    Macrophages are a functionally heterogeneous cell population that is mainly shaped by a variety of microenvironmental stimuli. Interferon γ (IFN-γ), interleukin-1β (IL-1β), and lipopolysaccharide (LPS) induce a classical activation of macrophages (M1), whereas IL-4 and IL-13 induce an alternative activation program in macrophages (M2). Reprogramming of intracellular metabolisms is required for the proper polarization and functions of activated macrophages. Similar to the Warburg effect observed in tumor cells, M1 macrophages increase glucose consumption and lactate release and decreased oxygen consumption rate. In comparison, M2 macrophages mainly employ oxidative glucose metabolism pathways. In addition, fatty acids, vitamins, and iron metabolisms are also related to macrophage polarization. However, detailed metabolic pathways involved in macrophages have remained elusive. Understanding the bidirectional interactions between cellular metabolism and macrophage functions in physiological and pathological situations and the regulatory pathways involved may offer novel therapies for macrophage-associated diseases.

  9. Alternative activation modifies macrophage resistance to Mycobacterium bovis.

    PubMed

    Castillo-Velázquez, Uziel; Aranday-Cortés, Elihú; Gutiérrez-Pabello, José A

    2011-07-01

    The aim of this study was to evaluate the influence of macrophage alternative activation in the intracellular pathogen natural disease resistance phenotype of the host. Macrophage monolayers from resistant (R) (3) or susceptible (S) (3) cattle donors were treated with 10 ng/ml of bovine recombinant IL-4 (rbIL-4), and infected with virulent and avirulent Mycobacterium bovis (MOI 10:1). Bactericidal assays were performed to assess the bacterial phagocytic index and intracellular survival. Total RNA was reverse transcribed and used to analyze the relative changes in gene expression of IL-10, IL-12, IL-18 IL-1β, TNF-α, MCP-1, MCP-2, IL-6, MIP-1, MIP-3, iNOS, ARGII and SLAM by real time PCR. Cell supernatants were collected and nitric oxide and arginase production was assessed. Apoptosis induction was measured by TUNEL. IL-4 treatment increased the phagocytic index in both R and S macrophages; however intracellular survival was augmented mainly in S macrophages. Alternative activation decreased gene expression of pro-inflammatory cytokines, nitric oxide production and DNA fragmentation mainly in R macrophages. On the other hand, arginase production was not different between R and S macrophages. Alternative activation modifies the macrophage response against M. bovis. IL-4 treatment minimized the functional differences that exist between R and S macrophages.

  10. The macrophage response to bacteria. Modulation of macrophage functional activity by peptidoglycan from Moraxella (Branhamella) catarrhalis.

    PubMed Central

    Keller, R; Gustafson, J E; Keist, R

    1992-01-01

    Moraxella (Branhamella) catarrhalis organisms have been shown to be particularly efficient in inducing in a pure population of bone marrow-derived mononuclear phagocytes secretory and cellular activities. In the present study, the ability of peptidoglycan from this Gram-negative organism to trigger a macrophage response was compared with that elicited by peptidoglycan from Staphylococcus aureus and Bacillus subtilis. The results show that the three peptidoglycans were similarly active in triggering the secretion of tumour necrosis factor and tumouricidal activity but differed considerably in their ability to induce the generation of nitrite in macrophages; in this respect, peptidoglycan from M. catarrhalis was particularly potent. The impressive capacity of M. catarrhalis peptidoglycan to induce in low concentration the secretion of tumour necrosis factor and nitrite and tumouricidal activity may, in addition to its lipopolysaccharide, contribute to the extraordinary potential of this organism to trigger the functional activities of macrophages. PMID:1516255

  11. Mycobacterium tuberculosis- induced neutrophil extracellular traps activate human macrophages.

    PubMed

    Braian, Clara; Hogea, Valentin; Stendahl, Olle

    2013-01-01

    Neutrophils activated by Mycobacterium tuberculosis (Mtb) form neutrophil extracellular traps (NETs), containing DNA and several biologically active cytosolic and granular proteins. These NETs may assist in the innate immune defense against different pathogens. We investigated whether the NET-forming neutrophils mediate an activating signal to macrophages during the early multicellular inflammatory reaction and granuloma formation. Mtb-induced NETs were found to be reactive oxygen species dependent and phagocytosis dependent. A neutrophil elastase inhibitor also delayed NET formation. However, NET formation occurred independently of Mtb-induced apoptosis. We observed close interactions between macrophages and Mtb-activated neutrophils, where macrophages bound and phagocytosed NETs. Significant secretion of the cytokines interleukin (IL)-6, tumor necrosis factor-α, IL-1β and IL-10 were detected from macrophages cocultured with NETs from Mtb-activated but not phorbol myristate acetate-activated neutrophils. NETs binding heat shock protein 72 (Hsp72) or recombinant Hsp72 were able to trigger cytokine release from macrophages. Only Mtb-induced NETs contained Hsp72, suggesting that these NETs can transfer this danger signal to adjacent macrophages. We propose that Hsp72 sequestered in NETs plays an important role in the interaction between neutrophils and macrophages during the early innate immune phase of an Mtb infection. The immunomodulatory role of NETs and proteins derived from them may influence not only chronic inflammation during tuberculosis but also immune regulation and autoimmunity.

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

    PubMed Central

    2014-01-01

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

  13. Brazilian Red Propolis Attenuates Inflammatory Signaling Cascade in LPS-Activated Macrophages

    PubMed Central

    Bueno-Silva, Bruno; Kawamoto, Dione; Ando-Suguimoto, Ellen S.; Alencar, Severino M.; Rosalen, Pedro L.; Mayer, Marcia P. A.

    2015-01-01

    Although previous studies suggested an anti-inflammatory property of Brazilian red propolis (BRP), the mechanisms involved in the anti-inflammatory effects of BRP and its activity on macrophages were still not elucidated. This study aimed to evaluate whether BRP attenuates the inflammatory effect of LPS on macrophages and to investigate its underlying mechanisms. BRP was added to RAW 264.7 murine macrophages after activation with LPS. NO production, cell viability, cytokines profile were evaluated. Activation of inflammatory signaling pathways and macrophage polarization were determined by RT-qPCR and Western blot. BRP at 50 μg/ml inhibited NO production by 78% without affecting cell viability. Cd80 and Cd86 were upregulated whereas mrc1 was down regulated by BRP indicating macrophage polarization at M1. BRP attenuated the production of pro-inflammatory mediators IL-12, GM-CSF, IFN-Ɣ, IL-1β in cell supernatants although levels of TNF- α and IL-6 were slightly increased after BRP treatment. Levels of IL-4, IL-10 and TGF-β were also reduced by BRP. BRP significantly reduced the up-regulation promoted by LPS of transcription of genes in inflammatory signaling (Pdk1, Pak1, Nfkb1, Mtcp1, Gsk3b, Fos and Elk1) and of Il1β and Il1f9 (fold-change rate > 5), which were further confirmed by the inhibition of NF-κB and MAPK signaling pathways. Furthermore, the upstream adaptor MyD88 adaptor-like (Mal), also known as TIRAP, involved in TLR2 and TLR4 signaling, was down- regulated in BRP treated LPS-activated macrophages. Given that BRP inhibited multiple signaling pathways in macrophages involved in the inflammatory process activated by LPS, our data indicated that BRP is a noteworthy food-source for the discovery of new bioactive compounds and a potential candidate to attenuate exhacerbated inflammatory diseases. PMID:26660901

  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. 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.

  16. 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

  17. Macrophage polarization in inflammatory diseases.

    PubMed

    Liu, Yan-Cun; Zou, Xian-Biao; Chai, Yan-Fen; Yao, Yong-Ming

    2014-01-01

    Diversity and plasticity are two hallmarks of macrophages. M1 macrophages (classically activated macrophages) are pro-inflammatory and have a central role in host defense against infection, while M2 macrophages (alternatively activated macrophages) are associated with responses to anti-inflammatory reactions and tissue remodeling, and they represent two terminals of the full spectrum of macrophage activation. Transformation of different phenotypes of macrophages regulates the initiation, development, and cessation of inflammatory diseases. Here we reviewed the characters and functions of macrophage polarization in infection, atherosclerosis, obesity, tumor, asthma, and sepsis, and proposed that targeting macrophage polarization and skewing their phenotype to adapt to the microenvironment might hold great promise for the treatment of inflammatory diseases.

  18. Macrophage activation and polarization modify P2X7 receptor secretome influencing the inflammatory process

    PubMed Central

    de Torre-Minguela, Carlos; Barberà-Cremades, Maria; Gómez, Ana I.; Martín-Sánchez, Fátima; Pelegrín, Pablo

    2016-01-01

    The activation of P2X7 receptor (P2X7R) on M1 polarized macrophages induces the assembly of the NLRP3 inflammasome leading to the release of pro-inflammatory cytokines and the establishment of the inflammatory response. However, P2X7R signaling to the NLRP3 inflammasome is uncoupled on M2 macrophages without changes on receptor activation. In this study, we analyzed P2X7R secretome in wild-type and P2X7R-deficient macrophages polarized either to M1 or M2 and proved that proteins released after P2X7R stimulation goes beyond caspase-1 secretome. The characterization of P2X7R-secretome reveals a new function of this receptor through a fine-tuning of protein release. We found that P2X7R stimulation in macrophages is able to release potent anti-inflammatory proteins, such as Annexin A1, independently of their polarization state suggesting for first time a potential role for P2X7R during resolution of the inflammation and not linked to the release of pro-inflammatory cytokines. These results are of prime importance for the development of therapeutics targeting P2X7R. PMID:26935289

  19. Molecular cloning and function characterization of a new macrophage-activating protein from Tremella fuciformis.

    PubMed

    Hung, Chih-Liang; Chang, An-Ju; Kuo, Xhao-Kai; Sheu, Fuu

    2014-02-19

    Silver ear mushroom ( Tremella fuciformis ) is an edible fungus with health benefits. In this study, we purified a new T. fuciformis protein (TFP) and demonstrated its ability to activate primary murine macrophages. The isolation procedure involved ammonium sulfate fractionation and ion exchange chromatography. TFP naturally formed a 24 kDa homodimeric protein and did not contain glycan residues. The TFP gene was cloned using the rapid amplification of cDNA ends method, and the cDNA sequence of TFP was composed of 408 nucleotides with a 336 nucleotide open reading frame encoding a 112 amino acid protein. TFP was capable of stimulating TNF-α, IL-1β, IL-1ra, and IL-12 production in addition to CD86/MHC class II expression, mRNA expression of M1-type chemokines, and nuclear NF-κB accumulation in murine peritoneal macrophage cells. Furthermore, TFP failed to stimulate TLR4-neutralized and TLR4-knockout macrophages, suggesting that TLR4 is a required receptor for TFP signaling on macrophages. Taken together, these results indicate that TFP may be an important bioactive compound from T. fuciformis that induces M1-polarized activation through a TLR4-dependent NF-κB signaling pathway. PMID:24400969

  20. Fish Oil-Derived Long-Chain n-3 Polyunsaturated Fatty Acids Reduce Expression of M1-Associated Macrophage Markers in an ex vivo Adipose Tissue Culture Model, in Part through Adiponectin.

    PubMed

    De Boer, Anna A; Monk, Jennifer M; Liddle, Danyelle M; Power, Krista A; Ma, David W L; Robinson, Lindsay E

    2015-01-01

    Adipose tissue (AT) macrophages (ATM) play a key role in obesity-associated pathologies, and their phenotype can be influenced by the local tissue microenvironment. Interestingly, long-chain n-3 polyunsaturated fatty acids (LC n-3 PUFA) and the LC n-3 PUFA-upregulated adipokine, adiponectin (Ad), may mitigate excessive ATM inflammatory M1-polarization responses. However, to what extent LC n-3 PUFA and Ad work in concert to affect macrophage phenotype has not been examined. Thus, we used an established ex vivo AT organ culture model using visceral AT from mice fed a control (CON; 10% w/w safflower oil) n-6 PUFA-rich diet or an isocaloric fish oil (FO; 3% w/w menhaden oil + 7% w/w safflower oil)-derived LC n-3 PUFA-rich diet to generate AT conditioned media (ACM). We then evaluated if CON or FO ACM affected macrophage polarization markers in a model designed to mimic acute [18 h ACM plus lipopolysaccharide (LPS) for the last 6 h] or chronic (macrophages treated with LPS-challenged CON or FO ACM for 24 h) inflammation ± Ad-neutralizing antibody and the LPS-neutralizing agent, polymyxin B. In the acute inflammation model, macrophages treated with FO ACM had decreased lipid uptake and mRNA expression of M1 markers (Nos2, Nfκb, Il6, Il18, Ccl2, and Ccl5) compared with CON ACM (p ≤ 0.05); however, these effects were largely attenuated when Ad was neutralized (p > 0.05). Furthermore, in the chronic inflammation model, macrophages treated with FO ACM had decreased mRNA expression of M1 markers (Nos2, Tnfα, Ccl2, and Il1β) and IL-6 and CCL2 secretion (p ≤ 0.05); however, some of these effects were lost when Ad was neutralized, and were further exacerbated when both Ad and LPS were neutralized. Taken together, this work shows that LC n-3 PUFA and Ad work in concert to suppress certain M1 macrophage responses. Thus, future strategies to modulate the ATM phenotype should consider the role of both LC n-3 PUFA and Ad in mitigating obese AT

  1. 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

  2. The macrophages in rheumatic diseases

    PubMed Central

    Laria, Antonella; Lurati, Alfredomaria; Marrazza, Mariagrazia; Mazzocchi, Daniela; Re, Katia Angela; Scarpellini, Magda

    2016-01-01

    Macrophages belong to the innate immune system giving us protection against pathogens. However it is known that they are also involved in rheumatic diseases. Activated macrophages have two different phenotypes related to different stimuli: M1 (classically activated) and M2 (alternatively activated). M1 macrophages release high levels of pro-inflammatory cytokines, reactive nitrogen and oxygen intermediates killing microorganisms and tumor cells; while M2 macrophages are involved in resolution of inflammation through phagocytosis of apoptotic neutrophils, reduced production of pro-inflammatory cytokines, and increased synthesis of mediators important in tissue remodeling, angiogenesis, and wound repair. The role of macrophages in the different rheumatic diseases is different according to their M1/M2 macrophages phenotype. PMID:26929657

  3. 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. PMID:25242651

  4. 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.

  5. Loss of MCP-1 alters macrophage polarization and reduces NFκB activation in the foreign body response

    PubMed Central

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

    2014-01-01

    Implantation of biomaterials elicits a foreign body response characterized by fusion of macrophages to form foreign body giant cells and fibrotic encapsulation. Studies of macrophage polarization 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 PDMS disks in the peritoneal cavity of WT and MCP-1 KO mice. We analyzed classical (M1) and alternative (M2) gene expression via Q-PCR, immunohistochemistry, and ELISA 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 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. PMID:25242651

  6. The synergistic interaction between the calcineurin B subunit and IFN-γ enhances macrophage antitumor activity

    PubMed Central

    Su, Z; Yang, R; Zhang, W; Xu, L; Zhong, Y; Yin, Y; Cen, J; DeWitt, J P; Wei, Q

    2015-01-01

    Macrophages are involved in tumor growth and progression. They infiltrate into tumors and cause inflammation, which creates a microenvironment favoring tumor growth and metastasis. However, certain stimuli may induce macrophages to act as tumor terminators. Here we report that the calcineurin B subunit (CnB) synergizes with IFN-γ to make macrophages highly cytotoxic to cancer cells. Furthermore, CnB and IFN-γ act synergistically to polarize mouse tumor-associated macrophages, as well as human monocyte-derived macrophages to an M1-like phenotype. This synergy is mediated by the crosstalk between CnB-engaged integrin αM-p38 MAPK signaling and IFN-γ-initiated p38/PKC-δ/Jak2 signaling. Interestingly, the signal transducer and activator of transcription 1 (STAT1) is a key factor that orchestrates the synergy of CnB and IFN-γ, and the phosphorylation status at Ser727 and Tyr701 of STAT1 is directly regulated by CnB and IFN-γ. PMID:25950470

  7. Active autophagy but not lipophagy in macrophages with defective lipolysis

    PubMed Central

    Schlager, Stefanie; Chandak, Prakash G.; Korbelius, Melanie; Gottschalk, Benjamin; Leopold, Christina; Obrowsky, Sascha; Rainer, Silvia; Doddapattar, Prakash; Aflaki, Elma; Wegscheider, Martin; Sachdev, Vinay; Graier, Wolfgang F.; Kolb, Dagmar; Radovic, Branislav; Kratky, Dagmar

    2015-01-01

    During autophagy, autophagosomes fuse with lysosomes to degrade damaged organelles and misfolded proteins. Breakdown products are released into the cytosol and contribute to energy and metabolic building block supply, especially during starvation. Lipophagy has been defined as the autophagy-mediated degradation of lipid droplets (LDs) by lysosomal acid lipase. Adipose triglyceride lipase (ATGL) is the major enzyme catalyzing the initial step of lipolysis by hydrolyzing triglycerides (TGs) in cytosolic LDs. Consequently, most organs and cells, including macrophages, lacking ATGL accumulate TGs, resulting in reduced intracellular free fatty acid concentrations. Macrophages deficient in hormone-sensitive lipase (H0) lack TG accumulation albeit reduced in vitro TG hydrolase activity. We hypothesized that autophagy is activated in lipase-deficient macrophages to counteract their energy deficit. We therefore generated mice lacking both ATGL and HSL (A0H0). Macrophages from A0H0 mice showed 73% reduced neutral TG hydrolase activity, resulting in TG-rich LD accumulation. Increased expression of cathepsin B, accumulation of LC3-II, reduced expression of p62 and increased DQ-BSA dequenching suggest intact autophagy and functional lysosomes in A0H0 macrophages. Markedly decreased acid TG hydrolase activity and lipid flux independent of bafilomycin A1 treatment, however, argue against effective lysosomal degradation of LDs in A0H0 macrophages. We conclude that autophagy of proteins and cell organelles but not of LDs is active as a compensatory mechanism to circumvent and balance the reduced availability of energy substrates in A0H0 macrophages. PMID:26143381

  8. Bion M1. Peculiarities of life activities of microbes in 30-day spaceflight

    NASA Astrophysics Data System (ADS)

    Viacheslav, Ilyin; Korshunov, Denis; Morozova, Julia; Voeikova, Tatiana; Tyaglov, Boris; Novikova, Liudmila; Krestyanova, Irina; Emelyanova, Lydia

    The aim of this work was to analyze the influence of space flight factors ( SFF) to microorganism strains , exposed inside unmanned spacecraft Bion M-1 during the 30- day space flight. Objectives of the work - the study of the influence of the SFF exchange chromosomal DNA in crosses microorganisms of the genus Streptomyces; the level of spontaneous phage induction of lysogenic strains fS31 from Streptomyces lividans 66 and Streptomyces coelicolor A3 ( 2 ) on the biosynthesis of the antibiotic tylosin strain of Streptomyces fradiae; survival electrogenic bacteria Shewanella oneidensis MR- 1 is used in the microbial fuel cell As a result of this work it was found that the SFF affect the exchange of chromosomal DNA by crossing strains of Streptomyces. Was detected polarity crossing , expressed in an advantageous contribution chromosome fragment of one of the parent strains in recombinant offspring. This fact may indicate a more prolonged exposure of cells in microgravity and , as a consequence, the transfer of longer fragments of chromosomal DNA This feature is the transfer of genetic material in microgravity could lead to wider dissemination and horizontal transfer of chromosomal and plasmid DNA of symbiotic microflora astronauts and other strains present in the spacecraft. It was shown no effect on the frequency of recombination PCF and the level of mutation model reversion of auxotrophic markers to prototrophy It was demonstrated that PCF increase the level of induction of cell actinophage fS31 lysogenic strain of S. lividans 66, but did not affect the level of induction of this phage cells S. coelicolor A3 ( 2). It is shown that the lower the level of synthesis PCF antibiotic aktinorodina (actinorhodin) in lysogenic strain S. coelicolor A3 ( 2). 66 Strains of S. lividans and S. coelicolor A3 ( 2 ) can be used as a biosensor for studying the effect on microorganisms PCF It is shown that the effect of the PCF reduces synthesis of tylosin and desmicosyn S. fradiae at

  9. Discovery and Characterization of Novel Allosteric Potentiators of M1 Muscarinic Receptors Reveals Multiple Modes of Activity

    PubMed Central

    Marlo, Joy E.; Niswender, Colleen M.; Days, Emily L.; Bridges, Thomas M.; Xiang, Yun; Rodriguez, Alice L.; Shirey, Jana K.; Brady, Ashley E.; Nalywajko, Tasha; Luo, Qingwei; Austin, Cheryl A.; Williams, Michael Baxter; Kim, Kwangho; Williams, Richard; Orton, Darren; Brown, H. Alex; Lindsley, Craig W.; Weaver, C. David; Conn, P. Jeffrey

    2009-01-01

    Activators of M1 muscarinic acetylcholine receptors (mAChRs) may provide novel treatments for schizophrenia and Alzheimer's disease. Unfortunately, the development of M1-active compounds has resulted in nonselective activation of the highly related M2 to M5 mAChR subtypes, which results in dose-limiting side effects. Using a functional screening approach, we identified several novel ligands that potentiated agonist activation of M1 with low micromolar potencies and induced 5-fold or greater leftward shifts of the acetylcholine (ACh) concentration-response curve. These ligands did not compete for binding at the ACh binding site, indicating that they modulate receptor activity by binding to allosteric sites. The two most selective compounds, cyclopentyl 1,6-dimethyl-4-(6-nitrobenzo[d][1,3]-dioxol-5-yl)-2-oxo-1,2,3,4-tetrahydropyrimidine-5-carboxylate (VU0090157) and (E)-2-(4-ethoxyphenylamino)-N′-((2-hydroxynaphthalen-1-yl)methylene)acetohydrazide (VU0029767), induced progressive shifts in ACh affinity at M1 that were consistent with their effects in a functional assay, suggesting that the mechanism for enhancement of M1 activity by these compounds is by increasing agonist affinity. These compounds were strikingly different, however, in their ability to potentiate responses at a mutant M1 receptor with decreased affinity for ACh and in their ability to affect responses of the allosteric M1 agonist, 1-[1′-(2-tolyl)-1,4′-bipiperidin-4-yl]-1,3-dihydro-2H-benzimidazol-2-one. Furthermore, these two compounds were distinct in their abilities to potentiate M1-mediated activation of phosphoinositide hydrolysis and phospholipase D. The discovery of multiple structurally distinct positive allosteric modulators of M1 is an exciting advance in establishing the potential of allosteric modulators for selective activation of this receptor. These data also suggest that structurally diverse M1 potentiators may act by distinct mechanisms and differentially regulate receptor

  10. Casticin induces ovarian cancer cell apoptosis by repressing FoxM1 through the activation of FOXO3a

    PubMed Central

    JIANG, LING; CAO, XIAO-CHENG; CAO, JIAN-GUO; LIU, FEI; QUAN, MEI-FANG; SHENG, XI-FENG; REN, KAI-QUN

    2013-01-01

    Casticin, a polymethoxyflavone, is reported to have anticancer activities. The aim of the present study was to examine the molecular mechanisms by which casticin induces apoptosis in ovarian cancer cells. The human ovarian cancer cell lines SKOV3 and A2780 were cultured in vitro. Various molecular techniques, including histone/DNA enzyme-linked immunosorbent assay (ELISA), reverse transcription polymerase chain reaction (RT-PCR), western blot analysis and gene transfection, were used to assess the expression of FOXO3a and forkhead box protein M1 (FoxM1) in casticin-treated ovarian cancer cell lines. Casticin-induced apoptotic cell death was accompanied by the activation of transcription factor FOXO3a, with a concomitant decrease in the expression levels of FoxM1 and its downstream target factors, namely survivin and polo-like kinase 1 (PLK1), and an increase in p27KIP1. A small inhibitory RNA (siRNA) knockout of FoxM1 potentiated casticin-induced apoptosis in ovarian cancer cells. Silencing FOXO3a expression using siRNA increased FoxM1 expression levels and clearly attenuated the induction of apoptosis by casticin treatment. These results show that casticin-induced apoptosis in ovarian cancer may be caused by the activation of FOXO3a, leading to FoxM1 inhibition. PMID:23761826

  11. An Antibody Biosensor Establishes the Activation of the M1 Muscarinic Acetylcholine Receptor during Learning and Memory*♦

    PubMed Central

    Butcher, Adrian J.; Bradley, Sophie J.; Prihandoko, Rudi; Brooke, Simon M.; Mogg, Adrian; Bourgognon, Julie-Myrtille; Macedo-Hatch, Timothy; Edwards, Jennifer M.; Bottrill, Andrew R.; Challiss, R. A. John; Broad, Lisa M.; Felder, Christian C.; Tobin, Andrew B.

    2016-01-01

    Establishing the in vivo activation status of G protein-coupled receptors would not only indicate physiological roles of G protein-coupled receptors but would also aid drug discovery by establishing drug/receptor engagement. Here, we develop a phospho-specific antibody-based biosensor to detect activation of the M1 muscarinic acetylcholine receptor (M1 mAChR) in vitro and in vivo. Mass spectrometry phosphoproteomics identified 14 sites of phosphorylation on the M1 mAChR. Phospho-specific antibodies to four of these sites established that serine at position 228 (Ser228) on the M1 mAChR showed extremely low levels of basal phosphorylation that were significantly up-regulated by orthosteric agonist stimulation. In addition, the M1 mAChR-positive allosteric modulator, 1-(4-methoxybenzyl)-4-oxo-1,4-dihydroquinoline-3-carboxylic acid, enhanced acetylcholine-mediated phosphorylation at Ser228. These data supported the hypothesis that phosphorylation at Ser228 was an indicator of M1 mAChR activation. This was further supported in vivo by the identification of phosphorylated Ser228 on the M1 mAChR in the hippocampus of mice following administration of the muscarinic ligands xanomeline and 1-(4-methoxybenzyl)-4-oxo-1,4-dihydroquinoline-3-carboxylic acid. Finally, Ser228 phosphorylation was seen to increase in the CA1 region of the hippocampus following memory acquisition, a response that correlated closely with up-regulation of CA1 neuronal activity. Thus, determining the phosphorylation status of the M1 mAChR at Ser228 not only provides a means of establishing receptor activation following drug treatment both in vitro and in vivo but also allows for the mapping of the activation status of the M1 mAChR in the hippocampus following memory acquisition thereby establishing a link between M1 mAChR activation and hippocampus-based memory and learning. PMID:26826123

  12. Contribution of Macrophage Polarization to Metabolic Diseases.

    PubMed

    Komohara, Yoshihiro; Fujiwara, Yukio; Ohnishi, Koji; Shiraishi, Daisuke; Takeya, Motohiro

    2016-01-01

    Macrophage activation is one of the major immunological events in the pathogenesis of various diseases. Recent studies have disclosed that complicated mechanisms are involved in macrophage activation and polarization, and many published research articles have been based on the M1/M2 polarization concept. It is considered that M1- and M2-like macrophages are associated with T helper (Th)1-type and Th2-type immune responses, respectively, via several immune mediators. In this article, we summarize the correlations between macrophage polarization and metabolic disorders in both humans and mice and discuss the contribution of macrophage polarization to the pathogenic process of metabolic diseases.

  13. p47 GTPases Regulate Toxoplasma gondii Survival in Activated Macrophages

    PubMed Central

    Butcher, Barbara A.; Greene, Robert I.; Henry, Stanley C.; Annecharico, Kimberly L.; Weinberg, J. Brice; Denkers, Eric Y.; Sher, Alan; Taylor, Gregory A.

    2005-01-01

    The cytokine gamma interferon (IFN-γ) is critical for resistance to Toxoplasma gondii. IFN-γ strongly activates macrophages and nonphagocytic host cells to limit intracellular growth of T. gondii; however, the cellular factors that are required for this effect are largely unknown. We have shown previously that IGTP and LRG-47, members of the IFN-γ-regulated family of p47 GTPases, are required for resistance to acute T. gondii infections in vivo. In contrast, IRG-47, another member of this family, is not required. In the present work, we addressed whether these GTPases are required for IFN-γ-induced suppression of T. gondii growth in macrophages in vitro. Bone marrow macrophages that lacked IGTP or LRG-47 displayed greatly attenuated IFN-γ-induced inhibition of T. gondii growth, while macrophages that lacked IRG-47 displayed normal inhibition. Thus, the ability of the p47 GTPases to limit acute infection in vivo correlated with their ability to suppress intracellular growth in macrophages in vitro. Using confocal microscopy and sucrose density fractionation, we demonstrated that IGTP largely colocalizes with endoplasmic reticulum markers, while LRG-47 was mainly restricted to the Golgi. Although both IGTP and LRG-47 localized to vacuoles containing latex beads, neither protein localized to vacuoles containing live T. gondii. These results suggest that IGTP and LRG-47 are able to regulate host resistance to acute T. gondii infections through their ability to inhibit parasite growth within the macrophage. PMID:15908352

  14. 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

  15. 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.

  16. 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.

  17. Palmitoleate Reverses High Fat-induced Proinflammatory Macrophage Polarization via AMP-activated Protein Kinase (AMPK)*

    PubMed Central

    Chan, Kenny L.; Pillon, Nicolas J.; Sivaloganathan, Darshan M.; Costford, Sheila R.; Liu, Zhi; Théret, Marine; Chazaud, Benedicte; Klip, Amira

    2015-01-01

    A rise in tissue-embedded macrophages displaying “M1-like” proinflammatory polarization is a hallmark of metabolic inflammation during a high fat diet or obesity. Here we show that bone marrow-derived macrophages (BMDM) from high fat-fed mice retain a memory of their dietary environment in vivo (displaying the elevated proinflammatory genes Cxcl1, Il6, Tnf, Nos2) despite 7-day differentiation and proliferation ex vivo. Notably, 6-h incubation with palmitoleate (PO) reversed the proinflammatory gene expression and cytokine secretion seen in BMDM from high fat-fed mice. BMDM from low fat-fed mice exposed to palmitate (PA) for 18 h ex vivo also showed elevated expression of proinflammatory genes (Cxcl1, Il6, Tnf, Nos2, and Il12b) associated with M1 polarization. Conversely, PO treatment increased anti-inflammatory genes (Mrc1, Tgfb1, Il10, Mgl2) and oxidative metabolism, characteristic of M2 macrophages. Therefore, saturated and unsaturated fatty acids bring about opposite macrophage polarization states. Coincubation of BMDM with both fatty acids counteracted the PA-induced Nos2 expression in a PO dose-dependent fashion. PO also prevented PA-induced IκBα degradation, RelA nuclear translocation, NO production, and cytokine secretion. Mechanistically, PO exerted its anti-inflammatory function through AMP-activated protein kinase as AMP kinase knockout or inhibition by Compound C offset the PO-dependent prevention of PA-induced inflammation. These results demonstrate a nutritional memory of BMDM ex vivo, highlight the plasticity of BMDM polarization in response to saturated and unsaturated fatty acids, and identify the potential to reverse diet- and saturated fat-induced M1-like polarization by administering palmitoleate. These findings could have applicability to reverse obesity-linked inflammation in metabolically relevant tissues. PMID:25987561

  18. Palmitoleate Reverses High Fat-induced Proinflammatory Macrophage Polarization via AMP-activated Protein Kinase (AMPK).

    PubMed

    Chan, Kenny L; Pillon, Nicolas J; Sivaloganathan, Darshan M; Costford, Sheila R; Liu, Zhi; Théret, Marine; Chazaud, Benedicte; Klip, Amira

    2015-07-01

    A rise in tissue-embedded macrophages displaying "M1-like" proinflammatory polarization is a hallmark of metabolic inflammation during a high fat diet or obesity. Here we show that bone marrow-derived macrophages (BMDM) from high fat-fed mice retain a memory of their dietary environment in vivo (displaying the elevated proinflammatory genes Cxcl1, Il6, Tnf, Nos2) despite 7-day differentiation and proliferation ex vivo. Notably, 6-h incubation with palmitoleate (PO) reversed the proinflammatory gene expression and cytokine secretion seen in BMDM from high fat-fed mice. BMDM from low fat-fed mice exposed to palmitate (PA) for 18 h ex vivo also showed elevated expression of proinflammatory genes (Cxcl1, Il6, Tnf, Nos2, and Il12b) associated with M1 polarization. Conversely, PO treatment increased anti-inflammatory genes (Mrc1, Tgfb1, Il10, Mgl2) and oxidative metabolism, characteristic of M2 macrophages. Therefore, saturated and unsaturated fatty acids bring about opposite macrophage polarization states. Coincubation of BMDM with both fatty acids counteracted the PA-induced Nos2 expression in a PO dose-dependent fashion. PO also prevented PA-induced IκBα degradation, RelA nuclear translocation, NO production, and cytokine secretion. Mechanistically, PO exerted its anti-inflammatory function through AMP-activated protein kinase as AMP kinase knockout or inhibition by Compound C offset the PO-dependent prevention of PA-induced inflammation. These results demonstrate a nutritional memory of BMDM ex vivo, highlight the plasticity of BMDM polarization in response to saturated and unsaturated fatty acids, and identify the potential to reverse diet- and saturated fat-induced M1-like polarization by administering palmitoleate. These findings could have applicability to reverse obesity-linked inflammation in metabolically relevant tissues.

  19. M1 macrophage infiltrations and histological changes in the liver after portal vein embolization using fibrinogen and OK432 in the rat.

    PubMed

    Sato, Tetsu; Marubashi, Shigeru; Kenjo, Akira; Tsuchiya, Takao; Kimura, Takashi; Sato, Naoya; Watanabe, Junichiro; Tasaki, Kazuhiro; Hashimoto, Yuko; Wada, Ikuo; Gotoh, Mitsukazu

    2016-05-01

    The mechanism of anti-tumor effect of transarterial Immuno-Embolization (TIE) using OK-432 has not been well elucidated. In this study, we aimed to investigate the tissue injury and immune response after portal venous embolization (PVE) with/without OK-432. Embolic materials (L group: lipiodol, LF group: lipiodol+fibrinogen, LO group: lipiodol+OK-432, LFO group: lipiodol+fibrinogen+OK-432) were administered via the right portal vein in Wistar rats. The histological findings in LFO group demonstrated liver damage with severe architectural changes. The concentrations of CD68(+) cells were observed in a time-dependent manner; it was significantly increased in the LO group on day 1 and in the LFO group on day 3. CD68(+)CD163(-) macrophages significantly increased in the LFO group on day 7 (P<0.05). In conclusion, PVE with fibrinogen and OK-432 markedly increased the CD68(+)CD163(-) infiltrating macrophages around the peri-portal area in the liver. This novel technique could be applied as immune-enhanced chemo-embolization of liver tumors. PMID:27062693

  20. Emodin Bidirectionally Modulates Macrophage Polarization and Epigenetically Regulates Macrophage Memory.

    PubMed

    Iwanowycz, Stephen; Wang, Junfeng; Altomare, Diego; Hui, Yvonne; Fan, Daping

    2016-05-27

    Macrophages are pleiotropic cells capable of performing a broad spectrum of functions. Macrophage phenotypes are classified along a continuum between the extremes of proinflammatory M1 macrophages and anti-inflammatory M2 macrophages. The seemingly opposing functions of M1 and M2 macrophages must be tightly regulated for an effective and proper response to foreign molecules or damaged tissue. Excessive activation of either M1 or M2 macrophages contributes to the pathology of many diseases. Emodin is a Chinese herb-derived compound and has shown potential to inhibit inflammation in various settings. In this study, we tested the ability of emodin to modulate the macrophage response to both M1 and M2 stimuli. Primary mouse macrophages were stimulated with LPS/IFNγ or IL4 with or without emodin, and the effects of emodin on gene transcription, cell signaling pathways, and histone modifications were examined by a variety of approaches, including microarray, quantitative real-time PCR, Western blotting, chromatin immunoprecipitation, and functional assays. We found that emodin bidirectionally tunes the induction of LPS/IFNγ- and IL4-responsive genes through inhibiting NFκB/IRF5/STAT1 signaling and IRF4/STAT6 signaling, respectively. Thereby, emodin modulates macrophage phagocytosis, migration, and NO production. Furthermore, emodin inhibited the removal of H3K27 trimethylation (H3K27m3) marks and the addition of H3K27 acetylation (H3K27ac) marks on genes required for M1 or M2 polarization of macrophages. In conclusion, our data suggest that emodin is uniquely able to suppress the excessive response of macrophages to both M1 and M2 stimuli and therefore has the potential to restore macrophage homeostasis in various pathologies.

  1. Enforced Expression of Hoxa3 Inhibits Classical and Promotes Alternative Activation of Macrophages In Vitro and In Vivo

    PubMed Central

    Al Sadoun, Hadeel; Burgess, Matthew; Hentges, Kathryn E.

    2016-01-01

    The regulated differentiation of macrophages (mφs) and their subsequent activation into proinflammatory or prohealing subtypes is critical for efficient wound healing. Chronic wounds such as diabetic (db) ulcers are associated with dysregulation of macrophage function. Whereas non-db mφs polarize to an M2-like, prohealing phenotype during the late stages of healing, db-derived mφs continue to display an M1-like, proinflammatory, or a mixed M1-like/M2-like phenotype. We have previously shown that sustained expression of Hoxa3 reduces the excessive number of leukocytes within the db wound; however, the effect of Hoxa3 on mφ polarization was unknown. In this study, we show that Hoxa3 protein transduction of mφs in vitro enhances macrophage maturation, inhibits M1 polarization, and promotes M2 polarization, in part via regulation of Pu.1/Spi1 and Stat6. Sustained expression of Hoxa3 in vivo in db wounds reduces the number of Nos2+ (M1-like) mφs, increases the number of Arg1+ and VEGF+ (M2-like) mφs, and accelerates healing in a DNA-binding independent manner. Our findings suggest a role for Hox protein activity in promoting M1-to-M2-like phenotypic switching via interactions with myeloid transcription factors and provide insight into mechanisms regulating this process in db wound healing. PMID:27342843

  2. Activation Biosensor for G Protein-Coupled Receptors: A FRET-Based m1 Muscarinic Activation Sensor That Regulates Gq

    PubMed Central

    Chang, Seungwoo; Ross, Elliott M.

    2012-01-01

    We describe the design, construction and validation of a fluorescence sensor to measure activation by agonist of the m1 muscarinic cholinergic receptor, a prototypical class I Gq-coupled receptor. The sensor uses an established general design in which Förster resonance energy transfer (FRET) from a circularly permuted CFP mutant to FlAsH, a selectively reactive fluorescein, is decreased 15–20% upon binding of a full agonist. Notably, the sensor displays essentially wild-type capacity to catalyze activation of Gαq, and the purified and reconstituted sensor displays appropriate regulation of affinity for agonists by Gq. We describe the strategies used to increase the agonist-driven change in FRET while simultaneously maintaining regulatory interactions with Gαq, in the context of the known structures of Class I G protein-coupled receptors. The approach should be generally applicable to other Class I receptors which include numerous important drug targets. PMID:23029161

  3. Human atherosclerotic plaque alternative macrophages display low cholesterol handling but high phagocytosis because of distinct activities of the PPARɣ and LXRα pathways

    PubMed Central

    Chinetti-Gbaguidi, Giulia; Baron, Morgane; Bouhlel, Mohamed Amine; Vanhoutte, Jonathan; Copin, Corinne; Sebti, Yasmine; Derudas, Bruno; Mayi, Thérèse; Bories, Gael; Tailleux, Anne; Haulon, Stéphane; Zawadzki, Christophe; Jude, Brigitte; Staels, Bart

    2011-01-01

    Rationale A crucial step in atherogenesis is the infiltration of the sub-endothelial space of large arteries by monocytes where they differentiate into macrophages and transform into lipid-loaded foam cells. Macrophages are heterogeneous cells which adapt their response to environmental cytokines. Th1 cytokines promote monocyte differentiation into M1 macrophages, while Th2 cytokines trigger an “alternative” M2 phenotype. Objective We previously reported the presence of CD68+MR+ M2 macrophages in human atherosclerotic plaques. However, the function of these plaque CD68+MR+ macrophages is still unknown. Methods and Results Histological analysis revealed that CD68+MR+ locate far from the lipid core of the plaque and contain smaller lipid droplets compared to CD68+MR− macrophages. IL-4 polarized CD68+MR+ display a reduced capacity to handle and efflux cellular cholesterol due to low expression levels of the nuclear receptor Liver X Receptor (LXR)α and its target genes, ABCA1 and ApoE, caused by the high 15-lipoxygenase activity in CD68+MR+ macrophages. By contrast, CD68+MR+ highly express opsonins and receptors involved in phagocytosis resulting in high phagocytic activity. In M2 macrophages, Peroxisome Proliferator-Activated receptor (PPAR)γ activation enhances the phagocytic, but not the cholesterol trafficking pathways. Conclusions These data identify a distinct macrophage sub-population with a low susceptibility to become foam cells, but high phagocytic activity due to different regulatory activities of the PPARγ-LXRα pathways. PMID:21350215

  4. Visualisation of nitric oxide generated by activated murine macrophages.

    PubMed

    Leone, A M; Furst, V W; Foxwell, N A; Cellek, S; Moncada, S

    1996-04-01

    We have visualised the release and approximate diffusion profile of nitric oxide (NO) from activated murine macrophages using a high transmission microscope coupled to a high sensitivity photon counting camera. The images generated by NO were cell-associated and spread over an area of approximately 175 micrometers from the activated macrophage. The signals obtained were dependent on the presence of exogenous L-arginine in the medium and followed a time course similar to that previously described for the generation of NO by the inducible form of NO synthase. The light signal was attenuated by the inhibitor of NO synthase, N omega-nitro-L-arginine methyl ester. Studies using superoxide-deficient macrophages further confirmed that the signals detected were generated by NO rather than reactive oxygen intermediates. PMID:8660339

  5. Activation of murine macrophages and lymphocytes by Ureaplasma diversum.

    PubMed Central

    Chelmonska-Soyta, A; Miller, R B; Ruhnke, L; Rosendal, S

    1994-01-01

    Ureaplasma diversum is a pathogen in the bovine reproductive tract. The objective of the research was to study interactions with macrophages and lymphocytes which might elucidate aspects of pathogenetic mechanisms of this organism. We studied the activation of murine macrophages of C3H/HeN (LPS-responder) and C3H/HeJ (LPS-low-responder) genotype for TNF-alpha, IL-6, IL-1 and nitric oxide production and blastogenic response of C3H/HeJ splenocytes after Ureaplasma diversum stimulation. Live and heat-killed U. diversum induced TNF-alpha, IL-6 and IL-1 in peritoneal macrophage cultures of both C3H/HeN and C3H/HeJ mice in a dose dependent manner. Interferon-gamma modulated the cytokine production, by increasing the production of TNF-alpha, IL-6 and nitric oxide, but IL-1 secretion was only enhanced in C3H/HeJ macrophages stimulated by live ureaplasmas. Supernatant of U. diversum sonicate was mitogenic for murine spleen lymphocytes. The blastogenic response was dose dependent, and stimulation with both U. diversum and Concanavalin A seemed to have an additive effect. These results suggest that U. diversum, similar to other mycoplasmas, activates murine macrophages and lymphoid cells. The studies should be repeated with bovine cells in order to elucidate pathogenetic aspects of inflammation in cattle caused by U. diversum. PMID:7889459

  6. 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

  7. Opposite Cross-Talk by Oleate and Palmitate on Insulin Signaling in Hepatocytes through Macrophage Activation*

    PubMed Central

    Pardo, Virginia; González-Rodríguez, Águeda; Guijas, Carlos; Balsinde, Jesús; Valverde, Ángela M.

    2015-01-01

    Chronic low grade inflammation in adipose tissue during obesity is associated with an impairment of the insulin signaling cascade. In this study, we have evaluated the impact of palmitate or oleate overload of macrophage/Kupffer cells in triggering stress-mediated signaling pathways, in lipoapoptosis, and in the cross-talk with insulin signaling in hepatocytes. RAW 264.7 macrophages or Kupffer cells were stimulated with oleate or palmitate, and levels of M1/M2 polarization markers and the lipidomic profile of eicosanoids were analyzed. Whereas proinflammatory cytokines and total eicosanoids were elevated in macrophages/Kupffer cells stimulated with palmitate, enhanced arginase 1 and lower leukotriene B4 (LTB4) levels were detected in macrophages stimulated with oleate. When hepatocytes were pretreated with conditioned medium (CM) from RAW 264.7 or Kupffer cells loaded with palmitate (CM-P), phosphorylation of stress kinases and endoplasmic reticulum stress signaling was increased, insulin signaling was impaired, and lipoapoptosis was detected. Conversely, enhanced insulin receptor-mediated signaling and reduced levels of the phosphatases protein tyrosine phosphatase 1B (PTP1B) and phosphatase and tensin homolog (PTEN) were found in hepatocytes treated with CM from macrophages stimulated with oleate (CM-O). Supplementation of CM-O with LTB4 suppressed insulin sensitization and increased PTP1B and PTEN. Furthermore, LTB4 decreased insulin receptor tyrosine phosphorylation in hepatocytes, activated the NFκB pathway, and up-regulated PTP1B and PTEN, these effects being mediated by LTB4 receptor BTL1. In conclusion, oleate and palmitate elicit an opposite cross-talk between macrophages/Kupffer cells and hepatocytes. Whereas CM-P interferes at the early steps of insulin signaling, CM-O increases insulin sensitization, possibly by reducing LTB4. PMID:25792746

  8. Inability of tumour cells to elicit the respiratory burst in cytotoxic, activated macrophages.

    PubMed Central

    Bryant, S M; Hill, H R

    1982-01-01

    Activated macrophages from Corynebacterium parvum-treated mice are cytotoxic to non-antibody-coated tumour cells and have an augmented respiratory burst potential when compared to resident macrophages. We have investigated the possible involvement of the respiratory burst as an effector mechanism in this type of tumour killing. Scavengers of toxic metabolites of oxygen such as catalase, superoxide dismutase, 2,3-dihydroxybenzoate, ethanol, and cytochrome c did not inhibit macrophage cytotoxicity in this system. To investigate whether or not neoplastic cells stimulate the macrophage respiratory burst, we exposed activated macrophages to viable tumour cells and monitored macrophage superoxide anion production, chemiluminescence, and hexose monophosphate shunt activity. None of these indicators of the macrophage respiratory burst was stimulated by the tumour cells towards which the macrophages were cytotoxic. The data suggest that the macrophages burst is not utilized as an effector mechanism in the non-antibody-mediated macrophage tumour cytotoxicity reaction. PMID:6277777

  9. Genome-Wide Analysis of Antiviral Signature Genes in Porcine Macrophages at Different Activation Statuses

    PubMed Central

    Sang, Yongming; Brichalli, Wyatt; Rowland, Raymond R. R.; Blecha, Frank

    2014-01-01

    Macrophages (MФs) can be polarized to various activation statuses, including classical (M1), alternative (M2), and antiviral states. To study the antiviral activation status of porcine MФs during porcine reproductive and respiratory syndrome virus (PRRSV) infection, we used RNA Sequencing (RNA-Seq) for transcriptomic analysis of differentially expressed genes (DEGs). Sequencing assessment and quality evaluation showed that our RNA-Seq data met the criteria for genome-wide transcriptomic analysis. Comparisons of any two activation statuses revealed more than 20,000 DEGs that were normalized to filter out 153–5,303 significant DEGs [false discovery rate (FDR) ≤0.001, fold change ≥2] in each comparison. The highest 5,303 significant DEGs were found between lipopolysaccharide- (LPS) and interferon (IFN)γ-stimulated M1 cells, whereas only 153 significant DEGs were detected between interleukin (IL)-10-polarized M2 cells and control mock-activated cells. To identify signature genes for antiviral regulation pertaining to each activation status, we identified a set of DEGs that showed significant up-regulation in only one activation state. In addition, pathway analyses defined the top 20–50 significantly regulated pathways at each activation status, and we further analyzed DEGs pertinent to pathways mediated by AMP kinase (AMPK) and epigenetic mechanisms. For the first time in porcine macrophages, our transcriptomic analyses not only compared family-wide differential expression of most known immune genes at different activation statuses, but also revealed transcription evidence of multiple gene families. These findings show that using RNA-Seq transcriptomic analyses in virus-infected and status-synchronized macrophages effectively profiled signature genes and gene response pathways for antiviral regulation, which may provide a framework for optimizing antiviral immunity and immune homeostasis. PMID:24505295

  10. Tumor-Cell Co-Culture Induced Alternative Activation of Macrophages Is Modulated by Interferons In Vitro

    PubMed Central

    Müller-Quernheim, Ulrike Carolin; Potthast, Lars; Müller-Quernheim, Joachim

    2012-01-01

    Tumor-associated macrophages infiltrate tumors and facilitate tumor growth. Here, we analyzed M1 and M2 marker expression in the course of co-culture-driven macrophage differentiation and investigated the influence of interferons (IFNs) on this differentiation. To generate monocyte-derived macrophages (MDMs) 1×106 monocytes of healthy volunteers were cultivated either with 25×103 adherent A549/mL or in medium containing 50% A549 conditioned medium (CM) for 72 h in the presence or absence of IFN-α, β or γ, respectively. Supernatants were tested for CCL18 (M2 marker) and CXCL10 (M1 marker) by enzyme-linked immunosorbent assay. CCL18 and CXCL10 release by MDM is increased by the presence of A549 cells, but also when cultured in A549 CM. On stimulation with IFN-γ, we observe an increased release of the M1 marker CXCL10 and a decreased release of CCL18. Type I IFNs also increases CXCL10 release. Thus, A549 releases a soluble factor which enhances CCL18 production and M2 polarization, indicating that a localized specific cytokine milieu, as found in the environment of a tumor or in fibrotic lung tissue, favors alternative activation of macrophages. In the presence of IFN-γ, M2 differentiation is attenuated as shown by the decrease of the M2 chemokine CCL18 and by the increase of the M1 chemokine CXCL10. However, CXCL10 levels were also increased by the co-culture, which indicates a simultaneous classical activation (M1) or the formation of a M1/M2 hybrid. PMID:22280057

  11. 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

  12. 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…

  13. 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...

  14. Activation of PPARγ by a Natural Flavonoid Modulator, Apigenin Ameliorates Obesity-Related Inflammation Via Regulation of Macrophage Polarization.

    PubMed

    Feng, Xiujing; Weng, Dan; Zhou, Feifei; Owen, Young D; Qin, Haohan; Zhao, Jingfa; WenYu; Huang, Yahong; Chen, Jiajia; Fu, Haijian; Yang, Nanfei; Chen, Dianhua; Li, Jianxin; Tan, Renxiang; Shen, Pingping

    2016-07-01

    PPARγ has emerged as a master regulator of macrophage polarization and is the molecular target of the thiazolidinedione drugs. Here we show that apigenin binds and activates PPARγ by acting as a modulator. Activation of PPARγ by apigenin blocks p65 translocation into nuclei through inhibition of p65/PPARγ complex translocation into nuclei, thereby decreasing NF-κB activation and favoringM2 macrophage polarization. In HFD and ob/ob mice, apigenin significantly reverses M1 macrophage into M2 and reduces the infiltration of inflammatory cells in liver and adipose tissues, as well as decreases the levels of pro-inflammatory cytokines, thereby alleviating inflammation. Strikingly, apigenin reduces liver and muscular steatosis, decreases the levels of ALT, AST, TC and TG, improving glucose resistance obviously. Unlike rosiglitazone, apigenin does not cause significant weight gain, osteoporosis et al. Our findings identify apigenin as a modulator of PPARγ and a potential lead compound for treatment of metabolic disorders. PMID:27374313

  15. Granulocyte-macrophage colony-stimulating factor primes interleukin-13 production by macrophages via protease-activated receptor-2.

    PubMed

    Aoki, Manabu; Yamaguchi, Rui; Yamamoto, Takatoshi; Ishimaru, Yasuji; Ono, Tomomichi; Sakamoto, Arisa; Narahara, Shinji; Sugiuchi, Hiroyuki; Hirose, Eiji; Yamaguchi, Yasuo

    2015-04-01

    Chronic inflammation is often linked to the presence of type 2-polarized macrophages, which are induced by the T helper type 2 cytokines interleukin-4 and interleukin-13 (IL-13). IL-13 is a key mediator of tissue fibrosis caused by T helper type 2-based inflammation. Human neutrophil elastase (HNE) plays a pivotal role in the pathogenesis of pulmonary fibrosis. This study investigated the priming effect of granulocyte-macrophage colony-stimulating factor (GM-CSF) on IL-13 expression by macrophages stimulated with HNE. Adherent macrophages were obtained from primary cultures of human mononuclear cells. Expression of IL-13 mRNA and protein by GM-CSF-dependent macrophages was investigated after stimulation with HNE, using the polymerase chain reaction and enzyme-linked immunosorbent assay. GM-CSF had a priming effect on IL-13 mRNA and protein expression by macrophages stimulated with HNE, while this effect was not observed for various other cytokines. GM-CSF-dependent macrophages showed a significant increase in the expression of protease activated receptor-2 (PAR-2) mRNA and protein. The response of IL-13 mRNA to HNE was significantly decreased by pretreatment with alpha1-antitrypsin, a PAR-2 antibody (SAM11), or a PAR-2 antagonist (ENMD-1068). These findings suggest that stimulation with HNE can induce IL-13 production by macrophages, especially GM-CSF-dependent macrophages. Accordingly, neutrophil elastase may have a key role in fibrosis associated with chronic inflammation.

  16. Macrophage activation and human immunodeficiency virus infection: HIV replication directs macrophages towards a pro-inflammatory phenotype while previous activation modulates macrophage susceptibility to infection and viral production.

    PubMed

    Porcheray, Fabrice; Samah, Boubekeur; Léone, Cathie; Dereuddre-Bosquet, Nathalie; Gras, Gabriel

    2006-05-25

    Macrophages are pivotal for the regulation of immune and inflammatory responses, but whether their role in HIV infection is protective or deleterious remains unclear. In this study, we investigated the effect of pro- and anti-inflammatory stimuli on macrophage sensitivity to two different aspects of HIV infection: their susceptibility to infection stricto sensu, which we measured by endpoint titration method, and their ability to support virus spread, which we measured by using an RT activity assay in infection kinetics. We show a partially protective role for pro-inflammatory agents as well as for IL-4. We also illustrate that various different stimuli display differential effects on macrophage susceptibility to HIV and on virus replication that occurs thereafter. On the other hand, HIV replication strongly repressed CD206 and CD163 expression, thus clearly orientating macrophages towards a pro-inflammatory phenotype, but independently of TNF. Taken together, our results emphasize that HIV infection of macrophages sets up inflammation at the cell level but through unexpected mechanisms. This may limit target susceptibility and participate in virus clearance but may also result in tissue damage.

  17. MiR-127 modulates macrophage polarization and promotes lung inflammation and injury by activating the JNK pathway.

    PubMed

    Ying, Hangjie; Kang, Yanhua; Zhang, Hang; Zhao, Dongjiu; Xia, Jingyan; Lu, Zhe; Wang, Huanhuan; Xu, Feng; Shi, Liyun

    2015-02-01

    A polarized macrophage response is presumed to have a pivotal role in a variety of immunological pathophysiology. However, the molecular mechanism underlying macrophage functional shaping remains largely unknown. In this study, we reveal a pivotal role of miR-127 in macrophage development and thereby the pathogenesis of inflammation and lung injury. In particular, miR-127 was demonstrated to be prominently induced upon TLR engagement and repressed by the M2-prone cytokines. Enforced expression of miR-127 in macrophages resulted in significantly increased production of proinflammatory cytokines, whereas deletion of miR-127 impaired M1 gene expression and led to a M2-biased response. Accordingly, intratracheal administration of miR-127 resulted in an exaggerated pulmonary inflammation and injury. Conversely, antagonizing of miR-127 suppressed production of the proinflammatory cytokines and rendered the mice more refractory to the inflammation-associated pathology. Mechanistically, miR-127 demonstrated to target B cell lymphoma 6 (Bcl6) and remarkably downregulated its expression and subsequently dual specificity phosphatase 1 (Dusp1), which in turn enhanced the activation of JNK kinase and hence the development of proinflammatory macrophages. Thereby, reconstitution with the expression of Bcl6 or Dusp1 or inhibition of JNK activity impaired miR-127-mediated skewing of M1 proinflammatory macrophages, whereas interference of Bcl6 or Dusp1 expression abrogated the anti-inflammatory property of anti-miR-127. Together, these data establish miR-127 as a molecular switch during macrophage development and as a potential target for treatment of inflammatory diseases.

  18. Biodegradable chitosan microparticles induce delayed STAT-1 activation and lead to distinct cytokine responses in differentially polarized human macrophages in vitro.

    PubMed

    Fong, David; Ariganello, Marianne B; Girard-Lauzière, Joël; Hoemann, Caroline D

    2015-01-01

    Current data suggest that chitosan activates wound macrophages to release endogenous factors that guide mesenchymal stem cell (MSC) to bone fractures. We tested the hypothesis that chitosan, a polymer containing glucosamine and N-acetyl glucosamine, stimulates macrophages in different polarization states to release functional MSC chemokines and mainly anabolic factors. Low-serum conditioned medium was collected from M0, M1 and M2a U937 macrophages previously differentiated with phorbol myristate acetate (PMA) and exposed or not for 24h to chitosan microparticles (80% degree of deacetylation, DDA, 130kDa). Chitosan particles were highly phagocytosed. Chitosan enhanced anabolic factor release from M0 and M2a macrophages (MCP-1, IP-10, MIP-1beta, IL-1ra, IL-10, PDGF), and IL-1beta release, with 25- to 400-fold excess IL-1ra over IL-1beta. In M1 macrophages, chitosan enhanced IL-1beta without enhancing or suppressing inflammatory factor release (IL-6, IP-10, IL-8). M0 and M2a macrophages, with or without chitosan stimulation, produced conditioned medium that promoted 2-fold more MSC chemotaxis than low-serum control medium, while M1-conditioned medium failed to induce MSC chemotaxis. Acetylated chitosan induced U937 macrophages to release IL-1ra without STAT-6 activation, and also induced a delayed STAT-1 activation/IP-10 release response that was not observed using non-biodegradable chitosan (98% DDA, 130kDa). In primary human macrophages, acetylated chitosan enhanced IL-1ra release without inducing IL-1beta, and required PMA priming to elicit STAT-1 activation and IP-10 release. We conclude that biodegradable chitosan particles enhance M0 and M2a macrophage anabolic responses independent of the IL4/STAT-6 axis, by inducing excess IL-1ra over IL-1beta and more chemokine release, without altering their inherent capacity to attract MSCs. PMID:25449925

  19. Phosphorylation of CRTC3 by the salt-inducible kinases controls the interconversion of classically activated and regulatory macrophages.

    PubMed

    Clark, Kristopher; MacKenzie, Kirsty F; Petkevicius, Kasparas; Kristariyanto, Yosua; Zhang, Jiazhen; Choi, Hwan Geun; Peggie, Mark; Plater, Lorna; Pedrioli, Patrick G A; McIver, Ed; Gray, Nathanael S; Arthur, J Simon C; Cohen, Philip

    2012-10-16

    Macrophages acquire strikingly different properties that enable them to play key roles during the initiation, propagation, and resolution of inflammation. Classically activated (M1) macrophages produce proinflammatory mediators to combat invading pathogens and respond to tissue damage in the host, whereas regulatory macrophages (M2b) produce high levels of anti-inflammatory molecules, such as IL-10, and low levels of proinflammatory cytokines, like IL-12, and are important for the resolution of inflammatory responses. A central problem in this area is to understand how the formation of regulatory macrophages can be promoted at sites of inflammation to prevent and/or alleviate chronic inflammatory and autoimmune diseases. Here, we demonstrate that the salt-inducible kinases (SIKs) restrict the formation of regulatory macrophages and that their inhibition induces striking increases in many of the characteristic markers of regulatory macrophages, greatly stimulating the production of IL-10 and other anti-inflammatory molecules. We show that SIK inhibitors elevate IL-10 production by inducing the dephosphorylation of cAMP response element-binding protein (CREB)-regulated transcriptional coactivator (CRTC) 3, its dissociation from 14-3-3 proteins and its translocation to the nucleus where it enhances a gene transcription program controlled by CREB. Importantly, the effects of SIK inhibitors on IL-10 production are lost in macrophages that express a drug-resistant mutant of SIK2. These findings identify SIKs as a key molecular switch whose inhibition reprograms macrophages to an anti-inflammatory phenotype. The remarkable effects of SIK inhibitors on macrophage function suggest that drugs that target these protein kinases may have therapeutic potential for the treatment of inflammatory and autoimmune diseases.

  20. Crosstalk between circadian rhythmicity, mitochondrial dynamics and macrophage bactericidal activity

    PubMed Central

    Oliva-Ramírez, Jacqueline; Moreno-Altamirano, María Maximina B; Pineda-Olvera, Benjamín; Cauich-Sánchez, Patricia; Sánchez-García, F Javier

    2014-01-01

    Biological functions show rhythmic fluctuations with 24-hr periodicity regulated by circadian proteins encoded by the so-called ‘clock’ genes. The absence or deregulation of circadian proteins in mice leads to metabolic disorders and in vitro models have shown that the synthesis of pro-inflammatory cytokines by macrophages follows a circadian rhythm so showing a link between circadian rhythmicity, metabolism and immunity. Recent evidence reveals that mitochondrial shape, position and size, collectively referred to as mitochondrial dynamics, are related to both cell metabolism and immune function. However, studies addressing the simultaneous crosstalk between circadian rhythm, mitochondrial dynamics and cell immune function are scarce. Here, by using an in vitro model of synchronized murine peritoneal macrophages, we present evidence that the mitochondrial dynamics and the mitochondrial membrane potential (Δψm) follow a circadian rhythmic pattern. In addition, it is shown that the fusion of mitochondria along with high Δψm, indicative of high mitochondrial activity, precede the highest phagocytic and bactericidal activity of macrophages on Salmonella typhimurium. Taken together, our results suggest a timely coordination between circadian rhythmicity, mitochondrial dynamics, and the bactericidal capacity of macrophages. PMID:24903615

  1. Quinoline-based clioquinol and nitroxoline exhibit anticancer activity inducing FoxM1 inhibition in cholangiocarcinoma cells

    PubMed Central

    Chan-on, Waraporn; Huyen, Nguyen Thi Bich; Songtawee, Napat; Suwanjang, Wilasinee; Prachayasittikul, Supaluk; Prachayasittikul, Virapong

    2015-01-01

    Purpose Fork head box M1 (FoxM1) is an oncogenic transcription factor frequently elevated in numerous cancers, including cholangiocarcinoma (CCA). A growing body of evidence documents its diverse functions contributing to tumorigenesis and cancer progression. As such, discovery of agents that can target FoxM1 would be valuable for the treatment of CCA. The quinoline-based compounds, namely clioquinol (CQ) and nitroxoline (NQ), represent a new class of anticancer drug. However, their efficacy and underlying mechanisms have not been elucidated in CCA. In this study, anticancer activities and inhibitory effects of CQ and NQ on FoxM1 signaling were explored using CCA cells. Methods The effects of CQ and NQ on cell viability and proliferation were evaluated using the colorimetric 3-(4,5-dimethylthiazol-2yl)-5-(3-carboxymethoxyphenyl)-(4-sulfophenyl)-2H-tetrazolium (MTS assay). Colony formation and cell migration affected by CQ and NQ were investigated using a clonogenic and a wound healing assay, respectively. To demonstrate the agents’ effects on FoxM1 signaling, expression levels of the target genes were quantitatively determined using real-time polymerase chain reaction. Results CQ and NQ significantly inhibited cell survival of HuCCT1 and Huh28 in a dose- and a time-dependent fashion. Further investigations using the rapidly proliferating HuCCT1 cells revealed significant suppression of cell proliferation and colony formation induced by low doses of the compounds. Treatment of CQ and NQ repressed expression of cyclin D1 but enhanced expression of p21. Most importantly, upon CQ and NQ treatment, expression of oncogenic FoxM1 was markedly decreased concomitant with downregulation of various FoxM1’s downstream targets including cdc25b, CENP-B, and survivin. In addition, the compounds distinctly impaired HuCCT1 migration as well as inhibited expression of matrix metalloproteinase (MMP)-2 and MMP-9. Conclusion Collectively, this study reports for the first time the

  2. Polyethylenimine-coated SPIONs trigger macrophage activation through TLR-4 signaling and ROS production and modulate podosome dynamics.

    PubMed

    Mulens-Arias, Vladimir; Rojas, José M; Pérez-Yagüe, Sonia; Morales, María P; Barber, Domingo F

    2015-06-01

    Polyethylenimine (PEI) is widely used as transfection agent in preclinical studies, both in vitro and in vivo. Due to their unique chemical and physical properties, SPIONs (superparamagnetic iron oxide nanoparticles) have been thoroughly studied as nanocarriers. PEI appears to activate different immune cells to an inflammatory response (M1/TH1), whereas the SPION-induced response seems to be context-dependent; the immunogenicity of the combination of these components has not been studied. Here we show that PEI-coated SPIONs (PMag) activate macrophages, as determined by measuring IL-12 secretion into culture medium and upregulation of several genes linked to the M1 phenotype. PMag-induced phosphorylation of p38 MAPK, p44/p42 MAPK and JNK, and upregulation of CD40, CD80, CD86 and I-A/I-E activation markers. PMag-induced macrophage activation depended partially on TLR4 (Toll-like receptor 4) and ROS (reactive oxygen species) signaling. Comparison of these responses with the LPS (lipopolysaccharide)-induced phenotype showed differences in gene expression profiling. PMag positively modulated podosome formation in murine macrophages, but hampered gelatin degradation by these cells. In conclusion, PMag induced an M1-like phenotype that was partially dependent on both TLR4 and ROS. These results show the adjuvant potential of PMag and suggest their use in vaccination schedules.

  3. Alternatively activated macrophages derived from monocytes and tissue macrophages are phenotypically and functionally distinct

    PubMed Central

    Gundra, Uma Mahesh; Girgis, Natasha M.; Ruckerl, Dominik; Jenkins, Stephen; Ward, Lauren N.; Kurtz, Zachary D.; Wiens, Kirsten E.; Tang, Mei San; Basu-Roy, Upal; Mansukhani, Alka; Allen, Judith E.

    2014-01-01

    Macrophages adopt an alternatively activated phenotype (AAMs) when activated by the interleukin-4receptor(R)α. AAMs can be derived either from proliferation of tissue resident macrophages or recruited inflammatory monocytes, but it is not known whether these different sources generate AAMs that are phenotypically and functionally distinct. By transcriptional profiling analysis, we show here that, although both monocyte and tissue-derived AAMs expressed high levels of Arg1, Chi3l3, and Retnla, only monocyte-derived AAMs up-regulated Raldh2 and PD-L2. Monocyte-derived AAMs were also CX3CR1-green fluorescent protein (GFP)high and expressed CD206, whereas tissue-derived AAMs were CX3CR1-GFP and CD206 negative. Monocyte-derived AAMs had high levels of aldehyde dehydrogenase activity and promoted the differentiation of FoxP3+ cells from naïve CD4+ cells via production of retinoic acid. In contrast, tissue-derived AAMs expressed high levels of uncoupling protein 1. Hence monocyte-derived AAM have properties associated with immune regulation, and the different physiological properties associated with AAM function may depend on the distinct lineage of these cells. PMID:24695852

  4. Macrophages as effector cells of protective immunity in murine schistosomiasis: macrophage activation in mice vaccinated with radiation-attenuated cercariae.

    PubMed Central

    James, S L; Natovitz, P C; Farrar, W L; Leonard, E J

    1984-01-01

    Cell-mediated immune responses contributing to macrophage activation were compared in mice that demonstrated partial resistance to challenge Schistosoma mansoni infection as a result of vaccination with radiation-attenuated cercariae or of ongoing low-grade primary infection. Vaccinated mice developed significant delayed hypersensitivity reactions to soluble schistosome antigens in vivo. Splenocytes from vaccinated animals responded to in vitro culture with various specific antigens (soluble adult worm extract, living or disrupted schistosomula) by proliferation and production of macrophage-activating lymphokines as did lymphocytes from S. mansoni-infected animals. Macrophage-activating factors produced by spleen cells from vaccinated mice upon specific antigen stimulation eluted as a single peak on Sephadex G-100 with a molecular weight of approximately 50,000 and contained gamma interferon activity. Moreover, peritoneal macrophages with larvicidal and tumoricidal activity were recovered from vaccinated mice after intraperitoneal challenge with soluble schistosome antigens, a procedure also observed to elicit activated macrophages in S. mansoni-infected animals. These observations demonstrate that vaccination with irradiated cercariae stimulates many of the same cellular responses observed after primary S. mansoni infection, and suggest that lymphokine-activated macrophages may participate in the effector mechanism of vaccine-induced and concomitant immunity to challenge schistosome infection. This is the first demonstration of a potential immune effector mechanism in the irradiated vaccine model. PMID:6609885

  5. Magnetometric measurements of macrophage activity in the liver after administration of different perfluorochemicals.

    PubMed

    Koester, M B; Lutz, J

    1994-01-01

    The activity of liver macrophages was evaluated using a magnetometric method after administration of different perfluorochemicals. Following treatment with perfluoroctylbromide a significant shorter time period of diminished macrophage activity was found compared with a mixture of perfluorodecalin and perfluorotripropylamine. Results obtained with the magnetometric method on liver macrophages were more sensitive compared with those of colloidal carbon clearance of total body RES.

  6. 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

  7. Delineation of Diverse Macrophage Activation Programs in Response to Intracellular Parasites and Cytokines

    PubMed Central

    Zhang, Shuyi; Kim, Charles C.; Batra, Sajeev; McKerrow, James H.; Loke, P'ng

    2010-01-01

    Background The ability to reside and proliferate in macrophages is characteristic of several infectious agents that are of major importance to public health, including the intracellular parasites Trypanosoma cruzi (the etiological agent of Chagas disease) and Leishmania species (etiological agents of Kala-Azar and cutaneous leishmaniasis). Although recent studies have elucidated some of the ways macrophages respond to these pathogens, the relationships between activation programs elicited by these pathogens and the macrophage activation programs elicited by bacterial pathogens and cytokines have not been delineated. Methodology/Principal Findings To provide a global perspective on the relationships between macrophage activation programs and to understand how certain pathogens circumvent them, we used transcriptional profiling by genome-wide microarray analysis to compare the responses of mouse macrophages following exposure to the intracellular parasites T. cruzi and Leishmania mexicana, the bacterial product lipopolysaccharide (LPS), and the cytokines IFNG, TNF, IFNB, IL-4, IL-10, and IL-17. We found that LPS induced a classical activation state that resembled macrophage stimulation by the Th1 cytokines IFNG and TNF. However, infection by the protozoan pathogen L. mexicana produced so few transcriptional changes that the infected macrophages were almost indistinguishable from uninfected cells. T. cruzi activated macrophages produced a transcriptional signature characterized by the induction of interferon-stimulated genes by 24 h post-infection. Despite this delayed IFN response by T. cruzi, the transcriptional response of macrophages infected by the kinetoplastid pathogens more closely resembled the transcriptional response of macrophages stimulated by the cytokines IL-4, IL-10, and IL-17 than macrophages stimulated by Th1 cytokines. Conclusions/Significance This study provides global gene expression data for a diverse set of biologically significant pathogens and

  8. Effects of inhibitors of tumoricidal activity upon schistosomulum killing by activated macrophages.

    PubMed

    James, S L; Glaven, J A

    1987-12-01

    Larvae of the helminth parasite Schistosoma mansoni are efficiently killed in vitro by lymphokine-activated macrophages, leading to the hypothesis that these cells may participate in the effector mechanism of protective immunity against schistosomiasis. Larvacidal activity has also been demonstrated in the IC-21 macrophage cell line in the absence of a demonstrable respiratory burst, indicating that macrophages possess nonoxidative mechanisms of schistosomulum killing. In this study, we demonstrated that IC-21 larval killing was most effective when contact was allowed between cells and target. Nonoxidative larvacidal activity was prevented by protein synthesis inhibitors, by the inhibition of microtubule polymerization, and by tosyllysylchloromethylketone but not by other inhibitors or substrates of tryptic or chymotryptic protease activity. The addition of excess iron to the culture also prevented IC-21-mediated larval killing, suggesting that the production of an iron-binding molecule may be involved. In contrast, the addition of excess thymidine or arginine did not reverse macrophage larvacidal activity, nor did lysosomotropic agents that depress the activity of acid hydrolases. Under appropriate conditions of activation and surface membrane stimulation, IC-21 cells could be induced to release soluble cytotoxic factors retaining larvacidal activity. These observations provide insight into the mechanism of macrophage-mediated schistosome killing, in comparison to the cytotoxic mechanisms described in the better-studied tumoricidal models, and supply a basis for further biochemical investigation of macrophage function against a multicellular target. PMID:3119500

  9. Effects of inhibitors of tumoricidal activity upon schistosomulum killing by activated macrophages.

    PubMed Central

    James, S L; Glaven, J A

    1987-01-01

    Larvae of the helminth parasite Schistosoma mansoni are efficiently killed in vitro by lymphokine-activated macrophages, leading to the hypothesis that these cells may participate in the effector mechanism of protective immunity against schistosomiasis. Larvacidal activity has also been demonstrated in the IC-21 macrophage cell line in the absence of a demonstrable respiratory burst, indicating that macrophages possess nonoxidative mechanisms of schistosomulum killing. In this study, we demonstrated that IC-21 larval killing was most effective when contact was allowed between cells and target. Nonoxidative larvacidal activity was prevented by protein synthesis inhibitors, by the inhibition of microtubule polymerization, and by tosyllysylchloromethylketone but not by other inhibitors or substrates of tryptic or chymotryptic protease activity. The addition of excess iron to the culture also prevented IC-21-mediated larval killing, suggesting that the production of an iron-binding molecule may be involved. In contrast, the addition of excess thymidine or arginine did not reverse macrophage larvacidal activity, nor did lysosomotropic agents that depress the activity of acid hydrolases. Under appropriate conditions of activation and surface membrane stimulation, IC-21 cells could be induced to release soluble cytotoxic factors retaining larvacidal activity. These observations provide insight into the mechanism of macrophage-mediated schistosome killing, in comparison to the cytotoxic mechanisms described in the better-studied tumoricidal models, and supply a basis for further biochemical investigation of macrophage function against a multicellular target. PMID:3119500

  10. 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.

  11. 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.

  12. Activation of FoxM1 Revitalizes the Replicative Potential of Aged β-Cells in Male Mice and Enhances Insulin Secretion

    PubMed Central

    Golson, Maria L.; Dunn, Jennifer C.; Maulis, Matthew F.; Dadi, Prasanna K.; Osipovich, Anna B.; Magnuson, Mark A.; Jacobson, David A.

    2015-01-01

    Type 2 diabetes incidence increases with age, while β-cell replication declines. The transcription factor FoxM1 is required for β-cell replication in various situations, and its expression declines with age. We hypothesized that increased FoxM1 activity in aged β-cells would rejuvenate proliferation. Induction of an activated form of FoxM1 was sufficient to increase β-cell mass and proliferation in 12-month-old male mice after just 2 weeks. Unexpectedly, at 2 months of age, induction of activated FoxM1 in male mice improved glucose homeostasis with unchanged β-cell mass. Cells expressing activated FoxM1 demonstrated enhanced glucose-stimulated Ca2+ influx, which resulted in improved glucose tolerance through enhanced β-cell function. Conversely, our laboratory has previously demonstrated that mice lacking FoxM1 in the pancreas display glucose intolerance or diabetes with only a 60% reduction in β-cell mass, suggesting that the loss of FoxM1 is detrimental to β-cell function. Ex vivo insulin secretion was therefore examined in size-matched islets from young mice lacking FoxM1 in β-cells. Foxm1-deficient islets indeed displayed reduced insulin secretion. Our studies reveal that activated FoxM1 increases β-cell replication while simultaneously enhancing insulin secretion and improving glucose homeostasis, making FoxM1 an attractive therapeutic target for diabetes. PMID:26251404

  13. GM-CSF Promotes Macrophage Alternative Activation after Renal Ischemia/Reperfusion Injury

    PubMed Central

    Huynh, Larry; Marlier, Arnaud; Lee, Yashang; Moeckel, Gilbert W.; Cantley, Lloyd G.

    2015-01-01

    After kidney ischemia/reperfusion (I/R) injury, monocytes home to the kidney and differentiate into activated macrophages. Whereas proinflammatory macrophages contribute to the initial kidney damage, an alternatively activated phenotype can promote normal renal repair. The microenvironment of the kidney during the repair phase mediates the transition of macrophage activation from a proinflammatory to a reparative phenotype. In this study, we show that macrophages isolated from murine kidneys during the tubular repair phase after I/R exhibit an alternative activation gene profile that differs from the canonical alternative activation induced by IL-4–stimulated STAT6 signaling. This unique activation profile can be reproduced in vitro by stimulation of bone marrow-derived macrophages with conditioned media from serum-starved mouse proximal tubule cells. Secreted tubular factors were found to activate macrophage STAT3 and STAT5 but not STAT6, leading to induction of the unique alternative activation pattern. Using STAT3-deficient bone marrow-derived macrophages and pharmacologic inhibition of STAT5, we found that tubular cell-mediated macrophage alternative activation is regulated by STAT5 activation. Both in vitro and after renal I/R, tubular cells expressed GM-CSF, a known STAT5 activator, and this pathway was required for in vitro alternative activation of macrophages by tubular cells. Furthermore, administration of a neutralizing antibody against GM-CSF after renal I/R attenuated kidney macrophage alternative activation and suppressed tubular proliferation. Taken together, these data show that tubular cells can instruct macrophage activation by secreting GM-CSF, leading to a unique macrophage reparative phenotype that supports tubular proliferation after sterile ischemic injury. PMID:25388222

  14. TLR activation of tumor-associated macrophages from ovarian cancer patients triggers cytolytic activity of NK cells.

    PubMed

    Bellora, Francesca; Castriconi, Roberta; Dondero, Alessandra; Pessino, Anna; Nencioni, Alessio; Liggieri, Giovanni; Moretta, Lorenzo; Mantovani, Alberto; Moretta, Alessandro; Bottino, Cristina

    2014-06-01

    We analyzed the functional outcome of the interaction between tumor-associated macrophages (TAMs) and natural killer (NK) cells. TAMs from ascites of ovarian cancer patients displayed an alternatively activated functional phenotype (M2) characterized by a remarkably high frequency and surface density of membrane-bound IL-18. Upon TLR engagement, TAMs acquired a classically activated functional phenotype (M1), released immunostimulatory cytokines (IL-12, soluble IL-18), and efficiently triggered the cytolytic activity of NK cells. TAMs also induced the release of IFN-γ from NK cells, which however was significantly lower compared with that induced by in vitro-polarized M2 cells. Most tumor-associated NK cells displayed a CD56(bright) , CD16(neg) or CD56(bright) , CD16(dim) phenotype, and very poor cytolytic activities, despite an increased expression of the activation marker CD69. They also showed downregulation of DNAM-1, 2B4, and NTB-A activating receptors, and an altered chemokine receptor repertoire. Importantly however, when appropriately stimulated, NK cells from the patients, including those cells isolated from ascites, efficiently killed autologous TAMs that expressed low, "nonprotective" levels of HLA class I molecules. Overall, our data show the existence of a complex tumor microenvironment in which poorly cytolytic/immature NK cells deal with immunosuppressive tumor-educated macrophages.

  15. Macrophage Activation Redirects Yersinia-Infected Host Cell Death from Apoptosis to Caspase-1-Dependent Pyroptosis

    PubMed Central

    Bergsbaken, Tessa; Cookson, Brad T

    2007-01-01

    Infection of macrophages by Yersinia species results in YopJ-dependent apoptosis, and naïve macrophages are highly susceptible to this form of cell death. Previous studies have demonstrated that macrophages activated with lipopolysaccharide (LPS) prior to infection are resistant to YopJ-dependent cell death; we found this simultaneously renders macrophages susceptible to killing by YopJ− Yersinia pseudotuberculosis (Yptb). YopJ− Yptb-induced macrophage death was dependent on caspase-1 activation, resulting in rapid permeability to small molecules, followed by membrane breakdown and DNA damage, and accompanied by cleavage and release of proinflammatory interleukin-18. Induction of caspase-1-dependent death, or pyroptosis, required the bacterial type III translocon but none of its known translocated proteins. Wild-type Yptb infection also triggered pyroptosis: YopJ-dependent activation of proapoptotic caspase-3 was significantly delayed in activated macrophages and resulted in caspase-1-dependent pyroptosis. The transition to susceptibility was not limited to LPS activation; it was also seen in macrophages activated with other Toll-like receptor (TLR) ligands and intact nonviable bacteria. Yptb infection triggered macrophage activation and activation of caspase-1 in vivo. Y. pestis infection of activated macrophages also stimulated caspase-1 activation. These results indicate that host signaling triggered by TLR and other activating ligands during the course of Yersinia infection redirects both the mechanism of host cell death and the downstream consequences of death by shifting from noninflammatory apoptosis to inflammatory pyroptosis. PMID:17983266

  16. 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

  17. Unlike PPAR{gamma}, PPAR{alpha} or PPAR{beta}/{delta} activation does not promote human monocyte differentiation toward alternative macrophages

    SciTech Connect

    Bouhlel, Mohamed Amine; Brozek, John; Derudas, Bruno; Zawadzki, Christophe; Jude, Brigitte; Staels, Bart; Chinetti-Gbaguidi, Giulia

    2009-08-28

    Macrophages adapt their response to micro-environmental signals. While Th1 cytokines promote pro-inflammatory M1 macrophages, Th2 cytokines promote an 'alternative' anti-inflammatory M2 macrophage phenotype. Peroxisome proliferator-activated receptors (PPARs) are ligand-activated transcription factors expressed in macrophages where they control the inflammatory response. It has been shown that PPAR{gamma} promotes the differentiation of monocytes into anti-inflammatory M2 macrophages in humans and mice, while a role for PPAR{beta}/{delta} in this process has been reported only in mice and no data are available for PPAR{alpha}. Here, we show that in contrast to PPAR{gamma}, expression of PPAR{alpha} and PPAR{beta}/{delta} overall does not correlate with the expression of M2 markers in human atherosclerotic lesions, whereas a positive correlation with genes of lipid metabolism exists. Moreover, unlike PPAR{gamma}, PPAR{alpha} or PPAR{beta}/{delta} activation does not influence human monocyte differentiation into M2 macrophages in vitro. Thus, PPAR{alpha} and PPAR{beta}/{delta} do not appear to modulate the alternative differentiation of human macrophages.

  18. 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.

  19. LL-37 immunomodulatory activity during Mycobacterium tuberculosis infection in macrophages.

    PubMed

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

    2015-12-01

    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.

  20. 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

  1. Identification of polarized macrophage subsets in zebrafish

    PubMed Central

    Nguyen-Chi, Mai; Laplace-Builhe, Béryl; Travnickova, Jana; Luz-Crawford, Patricia; Tejedor, Gautier; Phan, Quang Tien; Duroux-Richard, Isabelle; Levraud, Jean-Pierre; Kissa, Karima; Lutfalla, Georges

    2015-01-01

    While the mammalian macrophage phenotypes have been intensively studied in vitro, the dynamic of their phenotypic polarization has never been investigated in live vertebrates. We used the zebrafish as a live model to identify and trail macrophage subtypes. We generated a transgenic line whose macrophages expressing tumour necrosis factor alpha (tnfa), a key feature of classically activated (M1) macrophages, express fluorescent proteins Tg(mpeg1:mCherryF/tnfa:eGFP-F). Using 4D-confocal microscopy, we showed that both aseptic wounding and Escherichia coli inoculation triggered macrophage recruitment, some of which started to express tnfa. RT-qPCR on Fluorescence Activated Cell Sorting (FACS)-sorted tnfa+ and tnfa− macrophages showed that they, respectively, expressed M1 and alternatively activated (M2) mammalian markers. Fate tracing of tnfa+ macrophages during the time-course of inflammation demonstrated that pro-inflammatory macrophages converted into M2-like phenotype during the resolution step. Our results reveal the diversity and plasticity of zebrafish macrophage subsets and underline the similarities with mammalian macrophages proposing a new system to study macrophage functional dynamic. DOI: http://dx.doi.org/10.7554/eLife.07288.001 PMID:26154973

  2. Serum from patients with systemic vasculitis induces alternatively activated macrophage M2c polarization.

    PubMed

    Ohlsson, Susanne M; Linge, Carl Petrus; Gullstrand, Birgitta; Lood, Christian; Johansson, Asa; Ohlsson, Sophie; Lundqvist, Andrea; Bengtsson, Anders A; Carlsson, Fredric; Hellmark, Thomas

    2014-01-01

    Anti-neutrophil cytoplasmic antibody associated vasculitides (AAV) are conditions defined by an autoimmune small vessel inflammation. Dying neutrophils are found around the inflamed vessels and the balance between infiltrating neutrophils and macrophages is important to prevent autoimmunity. Here we investigate how sera from AAV patients may regulate macrophage polarization and function. Macrophages from healthy individuals were differentiated into M0, M1, M2a, M2b or M2c macrophages using a standardized protocol, and phenotyped according to their expression surface markers and cytokine production. These phenotypes were compared with those of macrophages stimulated with serum from AAV patients or healthy controls. While the healthy control sera induced a M0 macrophage, AAV serum promoted polarization towards the M2c subtype. No sera induced M1, M2a or M2b macrophages. The M2c subtype showed increased phagocytosis capacity compared with the other subtypes. The M2c polarization found in AAV is consistent with previous reports of increased levels of M2c-associated cytokines.

  3. Bioelectric modulation of macrophage polarization

    NASA Astrophysics Data System (ADS)

    Li, Chunmei; Levin, Michael; Kaplan, David L.

    2016-02-01

    Macrophages play a critical role in regulating wound healing and tissue regeneration by changing their polarization state in response to local microenvironmental stimuli. The native roles of polarized macrophages encompass biomaterials and tissue remodeling needs, yet harnessing or directing the polarization response has been largely absent as a potential strategy to exploit in regenerative medicine to date. Recent data have revealed that specific alteration of cells’ resting potential (Vmem) is a powerful tool to direct proliferation and differentiation in a number of complex tissues, such as limb regeneration, craniofacial patterning and tumorigenesis. In this study, we explored the bioelectric modulation of macrophage polarization by targeting ATP sensitive potassium channels (KATP). Glibenclamide (KATP blocker) and pinacidil (KATP opener) treatment not only affect macrophage polarization, but also influence the phenotype of prepolarized macrophages. Furthermore, modulation of cell membrane electrical properties can fine-tune macrophage plasticity. Glibenclamide decreased the secretion and gene expression of selected M1 markers, while pinacidil augmented M1 markers. More interestingly, glibencalmide promoted macrophage alternative activation by enhancing certain M2 markers during M2 polarization. These findings suggest that control of bioelectric properties of macrophages could offer a promising approach to regulate macrophage phenotype as a useful tool in regenerative medicine.

  4. Some biochemical and functional characteristics of macrophages activated by Tetrahymena pyriformis.

    PubMed

    Makioka, A; Kobayashi, A

    1984-01-01

    Phagocytosis, enzyme activities and capacity to release hydrogen peroxide (H2O2) and superoxide anion (O2-) of peritoneal macrophages from mice inoculated with Tetrahymena pyriformis, a free-living ciliate, were examined in comparison with resident and BCG-activated macrophages. Fc receptor-mediated phagocytosis of sheep erythrocytes was markedly increased in Tetrahymena-activated macrophages to the same level as that seen in BCG-activated ones. Tetrahymena-activated macrophages showed an increased level of acid phosphatase (lysosomal enzyme) and a reduced level of alkaline phosphodiesterase I (plasma membrane ectoenzyme) as compared with resident macrophages. Similar changes in the activities of the two enzymes were also observed in BCG-activated macrophages. Both Tetrahymena- and BCG-activated macrophages exhibited more enhanced capacity to release H2O2 and O2- than resident macrophages when stimulated with phorbol myristate acetate. In the macrophages from mice inoculated with varying doses of Tetrahymena, a significant correlation was observed between the increased capacity of H2O2 and O2- release as observed in the present study, and the enhanced toxoplasmacidal activity as observed in a previous study, in a dose-dependent fashion.

  5. Macrophage Activation Syndrome-Associated Markers in Severe Dengue

    PubMed Central

    Ab-Rahman, Hasliana Azrah; Rahim, Hafiz; AbuBakar, Sazaly; Wong, Pooi-Fong

    2016-01-01

    Hemophagocytosis, a phenomenon of which activated macrophages phagocytosed hematopoietic elements was reportedly observed in severe dengue patients. In the present study, we investigated whether markers of macrophage activation syndrome (MAS) can be used as differential diagnostic markers of severe dengue. Two hundred and eight confirmed dengue patients were recruited for the study. Sandwich ELISA was used to determine serum ferritin, soluble CD163 (sCD163), and soluble CD25 (sCD25) levels. The population of circulating CD163 (mCD163) monocytes was determined using flow cytometry. Receiver operating characteristic (ROC) analysis was plotted to determine the predictive validity of the biomarkers. Serum ferritin and sCD163 were found significantly increased in severe dengue patients compared to dengue fever patients (P = 0.003). A fair area under ROC curves (AUC) at 0.72 with a significant P value of 0.004 was observed for sCD163. sCD25 and mCD163 levels were not significantly different between severe dengue and dengue fever patients. Our findings suggest that in addition to serum ferritin, sCD163 can differentiate severe dengue from that of dengue fever patients. Hence, sCD163 level can be considered for use as a predictive marker for impending severe dengue. PMID:26941578

  6. 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.

  7. 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. PMID:8176226

  8. Activation of peritoneal macrophages to cytoxicity against B16 melanoma cells by Serratia marcescens polyribosome fractions

    SciTech Connect

    Hoover, S.K.

    1985-01-01

    Serratia marcescens polyribosomes (SMPR) have been shown to elicit an anti-tumor response in vivo. The in-vitro effects of SMPR on macrophages as the nonspecific mediators of the anti-tumor response have not previously been examined. The first objective of this research project is to corroborate and analyze the in-vivo results by the development and application of an in-vitro cytotoxicity assay. The second objective is to examine the effect of SMPR upon previously unstimulated peritoneal macrophages as representing the mechanism of cytotoxicity. The third objective is to identify the minimal effective component of SMPR responsible for an effect on macrophages. Results revealed that SMPR preparations exert a number of effects upon macrophages. Morphologic changes included increased spreading and increased perinuclear vacuolization. Macrophages were shown to be metabolically activate by two lines of evidence. SMPR-treated macrophages exhibited increased cellular metabolism by the increased uptake of /sup 3/H-thymidine and by the increased levels of secreted leucine aminopeptidase as compared to control macrophages. Results also showed that SMPR activates macrophages to cytotoxicity against syngeneic tumor target cells. Buoyant-density fractions were isolated and assayed for macrophage activating ability. Results showed 50S ribosomal subunits to be the smallest fraction effective for macrophage activation. Both the RNA and protein were necessary for complete effectiveness.

  9. 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

  10. Interaction of human leukocytes and Entamoeba histolytica. Killing of virulent amebae by the activated macrophage.

    PubMed

    Salata, R A; Pearson, R D; Ravdin, J I

    1985-08-01

    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

  11. 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.

  12. 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.

  13. The generation of macrophages with anti-inflammatory activity in the absence of STAT6 signaling

    PubMed Central

    Fleming, Bryan D.; Chandrasekaran, Prabha; Dillon, Laura A. L.; Dalby, Elizabeth; Suresh, Rahul; Sarkar, Arup; El-Sayed, Najib M.; Mosser, David M.

    2015-01-01

    Macrophages readily change their phenotype in response to exogenous stimuli. In this work, macrophages were stimulated under a variety of experimental conditions, and phenotypic alterations were correlated with changes in gene expression. We identified 3 transcriptionally related populations of macrophages with immunoregulatory activity. They were generated by stimulating cells with TLR ligands in the presence of 3 different "reprogramming" signals: high-density ICs, PGE2, or Ado. All 3 of these cell populations produced high levels of transcripts for IL-10 and growth and angiogenic factors. They also secreted reduced levels of inflammatory cytokines IL-1β, IL-6, and IL-12. All 3 macrophage phenotypes could partially rescue mice from lethal endotoxemia, and therefore, we consider each to have anti-inflammatory activity. This ability to regulate innate-immune responses occurred equally well in macrophages from STAT6-deficient mice. The lack of STAT6 did not affect the ability of macrophages to change cytokine production reciprocally or to rescue mice from lethal endotoxemia. Furthermore, treatment of macrophages with IL-4 failed to induce similar phenotypic or transcriptional alterations. This work demonstrates that there are multiple ways to generate macrophages with immunoregulatory activity. These anti-inflammatory macrophages are transcriptionally and functionally related to each other and are quite distinct from macrophages treated with IL-4. PMID:26048978

  14. Macrophage-oriented cytotoxic activity of novel triterpene saponins extracted from roots of Securidaca inappendiculata.

    PubMed

    Yui, S; Ubukata, K; Hodono, K; Kitahara, M; Mimaki, Y; Kuroda, M; Sashida, Y; Yamazaki, M

    2001-10-01

    It is recognized that macrophages in peripheral tissues often proliferate under pathological conditions such as tumors, inflammation and atherosclerosis. Because the growth state of macrophages is believed to be a factor regulating the pathological process of the diseases, substances that regulate macrophage growth or survival may be useful for disease control. In this paper, we identified the activity inhibiting macrophage growth in a hot water extract of roots of Securidaca inappendiculata. The extract markedly inhibited macrophage colony-stimulating factor (M-CSF/CSF-1)-induced growth of macrophages, whereas it exerted a less potent effect on growth of Concanavalin A (Con A)-stimulated thymocytes or M-CSF-stimulated bone marrow cells. The inhibition of macrophage growth was caused by a cytotoxic effect rather than a cytostatic effect. Cell death was due to the induction of apoptosis, as judged by staining with terminal deoxynucleotidyl transferase-mediated d-UTP nick end labelling (TUNEL). The cytotoxic activity seemed to be specific to peripheral macrophages; it showed a weak effect on the growth and survival of tumor cell lines including a macrophage-like cell line, J-774.1. Moreover, the saponin fraction induced apoptotic cell death of macrophages only when they were stimulated by M-CSF; it did not affect the viability of macrophages cultured without M-CSF or with granulocyte/macrophage-CSF. We determined the structures of the two active triterpene saponin compounds in the fraction, named securioside A and securioside B having a 3,4-dimethoxycinnamic group which is essential for the cell death-inducing activity. They are believed to be the primary compounds of new drugs for the treatment of pathological states in which macrophage proliferation occurs. PMID:11606030

  15. 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

  16. Inhibition of herpes simplex virus multiplication by activated macrophages: a role for arginase?

    PubMed Central

    Wildy, P; Gell, P G; Rhodes, J; Newton, A

    1982-01-01

    Proteose-peptone-activated mouse macrophages can prevent productive infection by herpes simplex virus in neighboring cells in vitro whether or not those cells belong to the same animal species. The effect does not require contact between the macrophages and the infected cells, may be prevented by adding extra arginine to the medium, and may be reversed when extra arginine is added 24 h after the macrophages. Arginase activity was found both intracellularly and released from the macrophages. The extracellular enzyme is quite stable; 64% activity was found after 48 h of incubation at 37 degrees C in tissue culture medium. No evidence was found that the inefficiency of virus replication in macrophages was due to self-starvation by arginase. As might be predicted macrophages can, by the same mechanism, limit productive infection by vaccinia virus. PMID:6286497

  17. AMPK-Activated Protein Kinase Suppresses Ccr2 Expression by Inhibiting the NF-κB Pathway in RAW264.7 Macrophages

    PubMed Central

    Kumase, Fumiaki; Takeuchi, Kimio; Morizane, Yuki; Suzuki, Jun; Matsumoto, Hidetaka; Kataoka, Keiko; Al-Moujahed, Ahmad; Maidana, Daniel E.; Miller, Joan W.; Vavvas, Demetrios G.

    2016-01-01

    C-C chemokine receptor 2 (Ccr2) is a key pro-inflammatory marker of classic (M1) macrophage activation. Although Ccr2 is known to be expressed both constitutively and inductively, the full regulatory mechanism of its expression remains unclear. AMP-activated protein kinase (AMPK) is not only a master regulator of energy homeostasis but also a central regulator of inflammation. In this study, we sought to assess AMPK’s role in regulating RAW264.7 macrophage Ccr2 protein levels in resting (M0) or LPS-induced M1 states. In both M0 and M1 RAW264.7 macrophages, knockdown of the AMPKα1 subunit by siRNA led to increased Ccr2 levels whereas pharmacologic (A769662) activation of AMPK, attenuated LPS-induced increases in Ccr2 expression in an AMPK dependent fashion. The increases in Ccr2 levels by AMPK downregulation were partially reversed by NF-κB inhibition whereas TNF-a inhibition had minimal effects. Our results indicate that AMPK is a negative regulator of Ccr2 expression in RAW264.7 macrophages, and that the mechanism of action of AMPK inhibition of Ccr2 is mediated, in part, through the NF-κB pathway. PMID:26799633

  18. Biosynthesis of nitric oxide activates iron regulatory factor in macrophages.

    PubMed

    Drapier, J C; Hirling, H; Wietzerbin, J; Kaldy, P; Kühn, L C

    1993-09-01

    Biosynthesis of nitric oxide (NO) from L-arginine modulates activity of iron-dependent enzymes, including mitochondrial acontiase, an [Fe-S] protein. We examined the effect of NO on the activity of iron regulatory factor (IRF), a cytoplasmic protein which modulates both ferritin mRNA translation and transferrin receptor mRNA stability by binding to specific mRNA sequences called iron responsive elements (IREs). Murine macrophages were activated with interferon-gamma and lipopolysaccharide to induce NO synthase activity and cultured in the presence or absence of NG-substituted analogues of L-arginine which served as selective inhibitors of NO synthesis. Measurement of the nitrite concentration in the culture medium was taken as an index of NO production. Mitochondria-free cytosols were then prepared and aconitase activity as well as IRE binding activity and induction of IRE binding activity were correlated and depended on NO synthesis after IFN-gamma and/or LPS stimulation. Authentic NO gas as well as the NO-generating compound 3-morpholinosydnonimine (SIN-1) also conversely modulated aconitase and IRE binding activities of purified recombinant IRF. These results provide evidence that endogenously produced NO may modulate the post-transcriptional regulation of genes involved in iron homeostasis and support the hypothesis that the [Fe-S] cluster of IRF mediates iron-dependent regulation. PMID:7504626

  19. Akt2 deficiency protects from acute lung injury via alternative macrophage activation and miR-146a induction in mice.

    PubMed

    Vergadi, Eleni; Vaporidi, Katerina; Theodorakis, Emmanuel E; Doxaki, Christina; Lagoudaki, Eleni; Ieronymaki, Eleftheria; Alexaki, Vassilia I; Helms, Mike; Kondili, Eumorfia; Soennichsen, Birte; Stathopoulos, Efstathios N; Margioris, Andrew N; Georgopoulos, Dimitrios; Tsatsanis, Christos

    2014-01-01

    Acute respiratory distress syndrome (ARDS) is a major cause of respiratory failure, with limited effective treatments available. Alveolar macrophages participate in the pathogenesis of ARDS. To investigate the role of macrophage activation in aseptic lung injury and identify molecular mediators with therapeutic potential, lung injury was induced in wild-type (WT) and Akt2(-/-) mice by hydrochloric acid aspiration. Acid-induced lung injury in WT mice was characterized by decreased lung compliance and increased protein and cytokine concentration in bronchoalveolar lavage fluid. Alveolar macrophages acquired a classical activation (M1) phenotype. Acid-induced lung injury was less severe in Akt2(-/-) mice compared with WT mice. Alveolar macrophages from acid-injured Akt2(-/-) mice demonstrated the alternative activation phenotype (M2). Although M2 polarization suppressed aseptic lung injury, it resulted in increased lung bacterial load when Akt2(-/-) mice were infected with Pseudomonas aeruginosa. miR-146a, an anti-inflammatory microRNA targeting TLR4 signaling, was induced during the late phase of lung injury in WT mice, whereas it was increased early in Akt2(-/-) mice. Indeed, miR-146a overexpression in WT macrophages suppressed LPS-induced inducible NO synthase (iNOS) and promoted M2 polarization, whereas miR-146a inhibition in Akt2(-/-) macrophages restored iNOS expression. Furthermore, miR-146a delivery or Akt2 silencing in WT mice exposed to acid resulted in suppression of iNOS in alveolar macrophages. In conclusion, Akt2 suppression and miR-146a induction promote the M2 macrophage phenotype, resulting in amelioration of acid-induced lung injury. In vivo modulation of macrophage phenotype through Akt2 or miR-146a could provide a potential therapeutic approach for aseptic ARDS; however, it may be deleterious in septic ARDS because of impaired bacterial clearance.

  20. Activation of α-7 Nicotinic Acetylcholine Receptor Reduces Ischemic Stroke Injury through Reduction of Pro-Inflammatory Macrophages and Oxidative Stress

    PubMed Central

    Han, Zhenying; Shen, Fanxia; He, Yue; Degos, Vincent; Camus, Marine; Maze, Mervyn; Young, William L.; Su, Hua

    2014-01-01

    Activation of α-7 nicotinic acetylcholine receptor (α-7 nAchR) has a neuro-protective effect on ischemic and hemorrhagic stroke. However, the underlying mechanism is not completely understood. We hypothesized that α-7 nAchR agonist protects brain injury after ischemic stroke through reduction of pro-inflammatory macrophages (M1) and oxidative stress. C57BL/6 mice were treated with PHA568487 (PHA, α-7 nAchR agonist), methyllycaconitine (MLA, nAchR antagonist), or saline immediately and 24 hours after permanent occlusion of the distal middle cerebral artery (pMCAO). Behavior test, lesion volume, CD68+, M1 (CD11b+/Iba1+) and M2 (CD206/Iba1+) microglia/macrophages, and phosphorylated p65 component of NF-kB in microglia/macrophages were quantified using histological stained sections. The expression of M1 and M2 marker genes, anti-oxidant genes and nicotinamide adenine dinucleotide phosphate (NADPH) oxidase were quantified using real-time RT-PCR. Compared to the saline-treated mice, PHA mice had fewer behavior deficits 3 and 7 days after pMCAO, and smaller lesion volume, fewer CD68+ and M1 macrophages, and more M2 macrophages 3 and 14 days after pMCAO, whereas MLA's effects were mostly the opposite in several analyses. PHA increased anti-oxidant genes and NADPH oxidase expression associated with decreased phosphorylation of NF-kB p65 in microglia/macrophages. Thus, reduction of inflammatory response and oxidative stress play roles in α-7 nAchR neuro-protective effect. PMID:25157794

  1. Phospholipid Ozonation Products Activate the 5-Lipoxygenase Pathway in Macrophages.

    PubMed

    Zemski Berry, Karin A; Murphy, Robert C

    2016-08-15

    Ozone is a highly reactive environmental toxicant that can react with the double bonds of lipids in pulmonary surfactant. This study was undertaken to investigate the proinflammatory properties of the major lipid-ozone product in pulmonary surfactant, 1-palmitoyl-2-(9'-oxo-nonanoyl)-glycerophosphocholine (16:0/9al-PC), with respect to eicosanoid production. A dose-dependent increase in the formation of 5-lipoxygenase (5-LO) products was observed in murine resident peritoneal macrophages (RPM) and alveolar macrophages (AM) upon treatment with 16:0/9al-PC. In contrast, the production of cyclooxygenase (COX) derived eicosanoids did not change from basal levels in the presence of 16:0/9al-PC. When 16:0/9al-PC and the TLR2 ligand, zymosan, were added to RPM or AM, an enhancement of 5-LO product formation along with a concomitant decrease in COX product formation was observed. Neither intracellular calcium levels nor arachidonic acid release was influenced by the addition of 16:0/9al-PC to RPM. Results from mitogen-activated protein kinase (MAPK) inhibitor studies and direct measurement of phosphorylation of MAPKs revealed that 16:0/9al-PC activates the p38 MAPK pathway in RPM, which results in the activation of 5-LO. Our results indicate that 16:0/9al-PC has a profound effect on the eicosanoid pathway, which may have implications in inflammatory pulmonary disease states where eicosanoids have been shown to play a role. PMID:27448436

  2. A transient reversal of miRNA-mediated repression controls macrophage activation.

    PubMed

    Mazumder, Anup; Bose, Mainak; Chakraborty, Abhijit; Chakrabarti, Saikat; Bhattacharyya, Suvendra N

    2013-11-01

    In mammalian macrophages, the expression of a number of cytokines is regulated by miRNAs. Upon macrophage activation, proinflammatory cytokine mRNAs are translated, although the expression of miRNAs targeting these mRNAs remains largely unaltered. We show that there is a transient reversal of miRNA-mediated repression during the early phase of the inflammatory response in macrophages, which leads to the protection of cytokine mRNAs from miRNA-mediated repression. This derepression occurs through Ago2 phosphorylation, which results in its impaired binding to miRNAs and to the corresponding target mRNAs. Macrophages expressing a mutant, non-phosphorylatable AGO2--which remains bound to miRNAs during macrophage activation--have a weakened inflammatory response and fail to prevent parasite invasion. These findings highlight the relevance of the transient relief of miRNA repression for macrophage function.

  3. Bactericidal Activity of Human Macrophages: Analysis of Factors Influencing the Killing of Listeria monocytogenes

    PubMed Central

    Cline, Martin J.

    1970-01-01

    A technique is described for the measurement of listericidal activity of human macrophages grown from blood monocytes. Phagocytosis of Listeria monocytogenes was inhibited by a glycolytic poison (NaF) but was unaffected by anaerobic conditions, cyanide, or 2,4-dinitrophenol (DNP). Killing by macrophages was slower than that by neutrophils, and Listeria phagocytized by macrophages began to synthesize deoxyribonucleic acid within 3 hr of the time of ingestion. Differentiated macrophages ingested and killed more organisms per cell than newly isolated monocytes. Maximal killing of Listeria required oxygen but was unaffected by cyanide or DNP. Macrophages isolated from patients with chronic intracellular infection (leprosy, tuberculosis, fungal diseases) and from patients with active Hodgkin's disease were more bactericidal than macrophages from normal subjects. Images PMID:16557814

  4. Liver X receptor activation stimulates iron export in human alternative macrophages

    PubMed Central

    Bories, Gael; Colin, Sophie; Vanhoutte, Jonathan; Derudas, Bruno; Copin, Corinne; Fanchon, Melanie; Daoudi, Mehdi; Belloy, Loic; Haulon, Stephan; Zawadzki, Christophe; Jude, Brigitte; Staels, Bart; Chinetti-Gbaguidi, Giulia

    2013-01-01

    Rationale In atherosclerotic plaques, iron preferentially accumulates in macrophages where it can exert pro-oxidant activities. Objective The objective of this study is, first, to better characterize the iron distribution and metabolism in macrophage sub-populations in human atherosclerotic plaques and, second, to determine whether iron homeostasis is under the control of nuclear receptors, such as the Liver X Receptors (LXR). Methods and Results Here we report that iron depots accumulate in human atherosclerotic plaque areas enriched in CD68 and Mannose Receptor (MR) positive (CD68+MR+) alternative M2 macrophages. In vitro IL-4 polarization of human monocytes into M2 macrophages also resulted in a gene expression profile and phenotype favouring iron accumulation. However, upon iron exposure, M2 macrophages acquire a phenotype favouring iron release, through a strong increase in ferroportin expression, illustrated by a more avid oxidation of extra-cellular LDL by iron-loaded M2 macrophages. In line, in human atherosclerotic plaques, CD68+MR+ macrophages accumulate oxidized lipids, which activate Liver X Receptors (LXRα and LXRβ), resulting in the induction of ABCA1, ABCG1 and ApoE expression. Moreover, in iron-loaded M2 macrophages, LXR activation induces nuclear factor erythroid 2-like 2 (NRF2) expression, hence increasing ferroportin expression, which, together with a decrease of hepcidin mRNA levels, promotes iron export. Conclusions These data identify a role for M2 macrophages in iron handling, a process which is regulated by LXR activation. PMID:24036496

  5. 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.

  6. Activation effect of Ganoderma lucidum polysaccharides liposomes on murine peritoneal macrophages.

    PubMed

    Liu, Zhenguang; Xing, Jie; Huang, Yee; Bo, Ruonan; Zheng, Sisi; Luo, Li; Niu, Yale; Zhang, Yan; Hu, Yuanliang; Liu, Jiaguo; Wu, Yi; Wang, Deyun

    2016-01-01

    The activation of murine peritoneal macrophages by Ganoderma lucidum polysaccharides liposomes (GLPL) was investigated in vitro. After treatment with GLPL, the changes of the nitric oxide (NO) secretion and iNOS (inducible nitric oxide synthase) activity were evaluated. The results showed that NO production and iNOS activity of macrophages were enhanced compared to GLP and BL group. In addition, both the phagocytic activity and levels of cytokines IL-1β, TNF-α and IFN-γ were enhanced in the peritoneal macrophages of mice by stimulation of GLPL. The expression of the major histocompatibility complex class II molecule (MHC II) on the surface of peritoneal macrophages significantly increased. These indicated that GLPL could enhance the activation of peritoneal macrophages and their potential for use as a delivery system of GLP. PMID:26529190

  7. Activation effect of Ganoderma lucidum polysaccharides liposomes on murine peritoneal macrophages.

    PubMed

    Liu, Zhenguang; Xing, Jie; Huang, Yee; Bo, Ruonan; Zheng, Sisi; Luo, Li; Niu, Yale; Zhang, Yan; Hu, Yuanliang; Liu, Jiaguo; Wu, Yi; Wang, Deyun

    2016-01-01

    The activation of murine peritoneal macrophages by Ganoderma lucidum polysaccharides liposomes (GLPL) was investigated in vitro. After treatment with GLPL, the changes of the nitric oxide (NO) secretion and iNOS (inducible nitric oxide synthase) activity were evaluated. The results showed that NO production and iNOS activity of macrophages were enhanced compared to GLP and BL group. In addition, both the phagocytic activity and levels of cytokines IL-1β, TNF-α and IFN-γ were enhanced in the peritoneal macrophages of mice by stimulation of GLPL. The expression of the major histocompatibility complex class II molecule (MHC II) on the surface of peritoneal macrophages significantly increased. These indicated that GLPL could enhance the activation of peritoneal macrophages and their potential for use as a delivery system of GLP.

  8. SIRT1 Suppresses Activator Protein-1 Transcriptional Activity and Cyclooxygenase-2 Expression in Macrophages*

    PubMed Central

    Zhang, Ran; Chen, Hou-Zao; Liu, Jin-Jing; Jia, Yu-Yan; Zhang, Zhu-Qin; Yang, Rui-Feng; Zhang, Yuan; Xu, Jing; Wei, Yu-Sheng; Liu, De-Pei; Liang, Chih-Chuan

    2010-01-01

    SIRT1 (Sirtuin type 1), a mammalian orthologue of yeast SIR2 (silent information regulator 2), has been shown to mediate a variety of calorie restriction (CR)-induced physiological events, such as cell fate regulation via deacetylation of the substrate proteins. However, whether SIRT1 deacetylates activator protein-1 (AP-1) to influence its transcriptional activity and target gene expression is still unknown. Here we demonstrate that SIRT1 directly interacts with the basic leucine zipper domains of c-Fos and c-Jun, the major components of AP-1, by which SIRT1 suppressed the transcriptional activity of AP-1. This process requires the deacetylase activity of SIRT1. Notably, SIRT1 reduced the expression of COX-2, a typical AP-1 target gene, and decreased prostaglandin E2 (PGE2) production of peritoneal macrophages (pMΦs). pMΦs with SIRT1 overexpression displayed improved phagocytosis and tumoricidal functions, which are associated with depressed PGE2. Furthermore, SIRT1 protein level was up-regulated in CR mouse pMΦs, whereas elevated SIRT1 decreased COX-2 expression and improved PGE2-related macrophage functions that were reversed following inhibition of SIRT1 deacetylase activity. Thus, our results indicate that SIRT1 may be a mediator of CR-induced macrophage regulation, and its deacetylase activity contributes to the inhibition of AP-1 transcriptional activity and COX-2 expression leading to amelioration of macrophage function. PMID:20042607

  9. Surface modification of nanoparticles enables selective evasion of phagocytic clearance by distinct macrophage phenotypes

    NASA Astrophysics Data System (ADS)

    Qie, Yaqing; Yuan, Hengfeng; von Roemeling, Christina A.; Chen, Yuanxin; Liu, Xiujie; Shih, Kevin D.; Knight, Joshua A.; Tun, Han W.; Wharen, Robert E.; Jiang, Wen; Kim, Betty Y. S.

    2016-05-01

    Nanomedicine is a burgeoning industry but an understanding of the interaction of nanomaterials with the immune system is critical for clinical translation. Macrophages play a fundamental role in the immune system by engulfing foreign particulates such as nanoparticles. When activated, macrophages form distinct phenotypic populations with unique immune functions, however the mechanism by which these polarized macrophages react to nanoparticles is unclear. Furthermore, strategies to selectively evade activated macrophage subpopulations are lacking. Here we demonstrate that stimulated macrophages possess higher phagocytic activities and that classically activated (M1) macrophages exhibit greater phagocytic capacity than alternatively activated (M2) macrophages. We show that modification of nanoparticles with polyethylene-glycol results in decreased clearance by all macrophage phenotypes, but importantly, coating nanoparticles with CD47 preferentially lowers phagocytic activity by the M1 phenotype. These results suggest that bio-inspired nanoparticle surface design may enable evasion of specific components of the immune system and provide a rational approach for developing immune tolerant nanomedicines.

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

    PubMed Central

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

    2016-01-01

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

  11. 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. PMID:26754935

  12. Hypoxia inhibits Moloney murine leukemia virus expression in activated macrophages.

    PubMed

    Puppo, Maura; Bosco, Maria Carla; Federico, Maurizio; Pastorino, Sandra; Varesio, Luigi

    2007-02-01

    Hypoxia, a local decrease in oxygen tension, occurring in many pathological processes, modifies macrophage (Mphi) gene expression and function. Here, we provide the first evidence that hypoxia inhibits transgene expression driven by the Moloney murine leukemia virus-long terminal repeats (MoMLV-LTR) in IFN-gamma-activated Mphi. Hypoxia silenced the expression of several MoMLV-LTR-driven genes, including v-myc, enhanced green fluorescence protein, and env, and was effective in different mouse Mphi cell lines and on distinct MoMLV backbone-based viruses. Down-regulation of MoMLV mRNA occurred at the transcriptional level and was associated with decreased retrovirus production, as determined by titration experiments, suggesting that hypoxia may control MoMLV retroviral spread through the suppression of LTR activity. In contrast, genes driven by the CMV or the SV40 promoter were up-regulated or unchanged by hypoxia, indicating a selective inhibitory activity on the MoMLV promoter. It is interesting that hypoxia was ineffective in suppressing MoMLV-LTR-controlled gene expression in T or fibroblast cell lines, suggesting a Mphi lineage-selective action. Finally, we found that MoMLV-mediated gene expression in Mphi was also inhibited by picolinic acid, a tryptophan catabolite with hypoxia-like activity and Mphi-activating properties, suggesting a pathophysiological role of this molecule in viral resistance and its possible use as an antiviral agent.

  13. Thromboxane A2 receptor antagonist SQ29548 reduces ischemic stroke-induced microglia/macrophages activation and enrichment, and ameliorates brain injury

    PubMed Central

    Yan, Aijuan; Zhang, Tingting; Yang, Xiao; Shao, Jiaxiang; Fu, Ningzhen; Shen, Fanxia; Fu, Yi; Xia, Weiliang

    2016-01-01

    Thromboxane A2 receptor (TXA2R) activation is thought to be involved in thrombosis/hemostasis and inflammation responses. We have previously shown that TXA2R antagonist SQ29548 attenuates BV2 microglia activation by suppression of ERK pathway, but its effect is not tested in vivo. The present study aims to explore the role of TXA2R on microglia/macrophages activation after ischemia/reperfusion brain injury in mice. Adult male ICR mice underwent 90-min transient middle cerebral artery occlusion (tMCAO). Immediately and 24 h after reperfusion, SQ29548 was administered twice to the ipsilateral ventricle (10 μl, 2.6 μmol/ml, per dose). Cerebral infarction volume, inflammatory cytokines release and microglia/macrophages activation were measured using the cresyl violet method, quantitative polymerase chain reaction (qPCR), and immunofluorescence double staining, respectively. Expression of TXA2R was significantly increased in the ipsilateral brain tissue after ischemia/reperfusion, which was also found to co-localize with activated microglia/macrophages in the infarct area. Administration of SQ29548 inhibited microglia/macrophages activation and enrichment, including both M1 and M2 phenotypes, and attenuated ischemia-induced IL-1ß, IL-6, and TNF-α up-regulation and iNOS release. TXA2R antagonist SQ29548 inhibited ischemia-induced inflammatory response and furthermore reduced microglia/macrophages activation and ischemic/reperfusion brain injury. PMID:27775054

  14. Macrophage activation of allogeneic lymphocyte proliferation in the guinea pig mixed leukocyte culture.

    PubMed

    Greineder, D K; Rosenthal, A S

    1975-05-01

    The role of the macrophage in the guinea pig mixed leukocyte culture was investigated. Macrophages obtained from oil-induced peritoneal exudates, peritoneal wash-out cells, spleen, and alveolar washings were found to be effective stimulators of allogeneic lymph node and splenic lymphocyte DNA synthesis. The stimulatory properties of macrophages proved radioresistant but viability dependent. Unfractionated lymph node cells or adherence column purified lymph node lymphocytes and thymocytes were only minimally active as stimulators, even in the presence of macrophages syngeneic to the responder lymphocytes. Allogeneic fibroblasts, polymorphonuclear leukocytes, L2C leukemia cells, and xenogeneic (murine) macrophages failed to simulate. These data provide evidence that the macrophage is the predominant stimulator of the mixed leukocyte culture in the guinea pig.

  15. 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

  16. Cell Motility Is Decreased in Macrophages Activated by Cancer Cell-Conditioned Medium

    PubMed Central

    Go, Ahreum; Ryu, Yun-Kyoung; Lee, Jae-Wook; Moon, Eun-Yi

    2013-01-01

    Macrophages play a role in innate immune responses to various foreign antigens. Many products from primary tumors influence the activation and transmigration of macrophages. Here, we investigated a migration of macrophages stimulated with cancer cell culture-conditioned medium (CM). Macrophage activation by treatment with CM of B16F10 cells were judged by the increase in protein levels of inducible nitric oxide synthase (iNOS) and cyclooxygenase 2 (COX2). The location where macrophages were at 4 h-incubation with control medium or CM was different from where they were at 5 h-incubation in culture dish. Percentage of superimposed macrophages at every 1 h interval was gradually increased by CM treatment as compared to control. Total coverage of migrated track expressed in coordinates was smaller and total distance of migration was shorter in CM-treated macrophages than that in control. Rac1 activity in CM-treated macrophages was also decreased as compared to that in control. When macrophages were treated with CM in the presence of dexamethasone (Dex), an increase in COX2 protein levels, and a decrease in Rac1 activity and total coverage of migration were reversed. In the meanwhile, biphasic changes were detected by Dex treatment in section distance of migration at each time interval, which was more decreased at early time and then increased at later time. Taken together, data demonstrate that macrophage motility could be reduced in accordance with activation in response to cancer cell products. It suggests that macrophage motility could be a novel marker to monitor cancer-associated inflammatory diseases and the efficacy of anti-inflammatory agents. PMID:24404340

  17. Atomic-Scale Determination of Active Facets on the MoVTeNb Oxide M1 Phase and Their Intrinsic Catalytic Activity for Ethane Oxidative Dehydrogenation.

    PubMed

    Melzer, Daniel; Xu, Pinghong; Hartmann, Daniela; Zhu, Yuanyuan; Browning, Nigel D; Sanchez-Sanchez, Maricruz; Lercher, Johannes A

    2016-07-25

    Aberration-corrected high-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM) has been used to image the basal {001} plane of the catalytically relevant M1 phase in MoVTeNb complex oxides. Facets {010}, {120}, and {210} are identified as the most frequent lateral termination planes of the crystals. Combination of STEM with He ion microscopy (HIM) images, Rietveld analysis, and kinetic tests reveals that the activation of ethane is correlated to the availability of facets {001}, {120}, and {210} at the surface of M1 crystals. The lateral facets {120} and {210} expose crystalline positions related to the typical active centers described for propane oxidation. Conversely, the low activity of the facet {010} is attributed to its configuration, consisting of only stable M6 O21 units connected by a single octahedron. Thus, we quantitatively demonstrated that differences in catalytic activity among M1 samples of equal chemical composition depend primarily on the morphology of the particles, which determines the predominant terminating facets. PMID:26990594

  18. 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.

  19. Association of mitogen-activated protein kinases with microtubules in mouse macrophages

    PubMed Central

    1996-01-01

    Taxol, a microtubule-binding diterpene, mimics many effects of lipopolysaccharide (LPS) on mouse macrophages. The LPS-mimetic effects of taxol appear to be under the same genetic control as responses to LPS itself. Thus we have postulated a role for microtubule-associated proteins (MAP) in the response of macrophages to LPS. Stimulation of macrophages by LPS quickly induces the activation of mitogen-activated protein kinases (MAPK). MAPK are generally considered cytosolic enzymes. Herein we report that much of the LPS-activatable pool of MAPK in primary mouse peritoneal macrophages is microtubule associated. By immunofluorescence, MAPK were localized to colchicine- and nocodazole- disruptible filaments. From both mouse brain and RAW 264.7 macrophages, MAPK could be coisolated with polymerized tubulin. Fractionation of primary macrophages into cytosol-, microfilament-, microtubule-, and intermediated filament-rich extracts revealed that approximately 10% of MAPK but none of MAPK kinase (MEK1A and MEK2) was microtubule bound. Exposure of macrophages to LPS did not change the proportion of MAPK bound to microtubules, but preferentially activated the microtubule- associated pool. These findings confirm the prediction that LPS activates a kinase bound to microtubules. Together with LPS-mimetic actions of taxol and the shared genetic control of responses to LPS and taxol, these results support the hypothesis that a major LPS-signaling pathway in mouse macrophages may involve activation of one or more microtubule-associated kinases. PMID:8666946

  20. Hybrid-Actuating Macrophage-Based Microrobots for Active Cancer Therapy.

    PubMed

    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

  1. 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

  2. In Vitro Administration of Gold Nanoparticles Functionalized with MUC-1 Protein Fragment Generates Anticancer Vaccine Response via Macrophage Activation and Polarization Mechanism

    PubMed Central

    Mocan, Teodora; Matea, Cristian; Tabaran, Flaviu; Iancu, Cornel; Orasan, Remus; Mocan, Lucian

    2015-01-01

    Therapeutic cancer vaccines (or active immunotherapy) aim to guide the patient's personal immune system to eradicate cancer cells. An exciting approach to cancer vaccines has been offered by nanoscale drug delivery systems containing tumor associated antigens (TAAs). Their capacity to stimulate the immune system has been suggested during late years. However, the role of the macrophages as key-elements in antigen-presentation process following TAAs-containing nanosystems is not completely understood. We aimed to evaluate the effect of gold nanoparticles functionalized with mucin-1 peptide (MUC-1) on murine peritoneal macrophages. Gold nanoparticles, obtained using a modified Turkevich method, were functionalized with MUC-1 protein using Clealand's reagent. The obtained GNP-MUC-1 solution was used to treat at various concentrations monolayers of peritoneum-derived macrophages that were further analyzed using confocal and hyperspectral microscopy, ELISA assays and spectroscopic techniques. The GNP-MUC-1 nano-construct had proven to function as a powerful macrophage activator with consequent release of cytokines such as: TNF-ɑ, IL-6, IL-10 and IL-12 on peritoneal macrophages we have isolated from mice. Our results demonstrate optimization of antigen-presenting process and predominant M1 polarization following exposure GNP-MUC-1. To our best knowledge this is the first study to evaluate the anticancer effects of a newly designed nano-biocompound on the complex antigen- processing apparatus of peritoneal macrophages. PMID:26000051

  3. Puerarin Inhibits oxLDL-Induced Macrophage Activation and Foam Cell Formation in Human THP1 Macrophage.

    PubMed

    Zhang, Heng; Zhai, Zhenhua; Zhou, Hongyu; Li, Yao; Li, Xiaojie; Lin, Yuhan; Li, Weihong; Shi, Yueping; Zhou, Ming-Sheng

    2015-01-01

    Puerarin, an isoflavone derived from Kudzu roots, has been widely used for treatment of cardiovascular and cerebral vascular diseases in China and other Asian countries. However, the underlying mechanisms are largely unknown. The present study investigated whether puerarin inhibited atherogenic lipid oxLDL-mediated macrophage activation and foam cell formation in human THP1 macrophage. Treatment with oxLDL significantly increased the mRNA expression of proinflammatory cytokines tumor necrosis factor α (TNFα, 160%) and interleukin (IL) 1β (13 fold) accompanied by upregulation of toll-like receptor 4 (TLR4, 165%) and the ratio of phospho-IκBα/IκBα in THP1 macrophage. Puerarin dose-dependently prevented an increase in oxLDL-induced proinflammatory gene expression with downregulation of TLR4 and the ratio of phospho-IκBα/IκBα. Furthermore, puerarin prevented oxLDL-mediated lipid deposition and foam cell formation associated with downregulation of scavenger receptor CD36. Flow cytometry analysis showed that puerarin reduced the number of early apoptotic cells of macrophages induced by oxLDL. Our results show that puerarin has anti-inflammatory and antiatherogenic effects in vitro; the underlying mechanisms may involve the inhibition of TLR4/NFκB pathway and downregulation of CD36 expression. The results from the present study provide scientific evidence and may expand our armamentarium to use puerarin for prevention and treatment of cardiovascular and atherosclerotic diseases. PMID:26576421

  4. Activation of macrophages for destruction of Francisella tularensis: identification of cytokines, effector cells, and effector molecules.

    PubMed Central

    Fortier, A H; Polsinelli, T; Green, S J; Nacy, C A

    1992-01-01

    Francisella tularensis live vaccine strain (LVS) was grown in culture with nonadherent resident, starch-elicited, or Proteose Peptone-elicited peritoneal cells. Numbers of bacteria increased 4 logs over the input inoculum in 48 to 72 h. Growth rates were faster in inflammatory cells than in resident cells: generation times for the bacterium were 3 h in inflammatory cells and 6 h in resident macrophages. LVS-infected macrophage cultures treated with lymphokines did not support growth of the bacterium, although lymphokines alone had no inhibitory effects on replication of LVS in culture medium devoid of cells. Removal of gamma interferon (IFN-gamma) by immunoaffinity precipitation rendered lymphokines ineffective for induction of macrophage anti-LVS activity, and recombinant IFN-gamma stimulated both resident and inflammatory macrophage populations to inhibit LVS growth in vitro. Inflammatory macrophages were more sensitive to effects of IFN-gamma: half-maximal activity was achieved at 5 U/ml for inflammatory macrophages and 20 U/ml for resident macrophages. IFN-gamma-induced anti-LVS activity correlated with the production of nitrite (NO2-), an oxidative end product of L-arginine-derived nitric oxide (NO). Anti-LVS activity and nitrite production were both completely inhibited by the addition of either the L-arginine analog NG-monomethyl-L-arginine or anti-tumor necrosis factor antibodies to activated macrophage cultures. Thus, macrophages can be activated by IFN-gamma to suppress the growth of F. tularensis by generation of toxic levels of NO, and inflammatory macrophages are substantially more sensitive to activation activities of IFN-gamma for this effector reaction than are more differentiated resident cells. PMID:1541555

  5. Human macrophage activation. Modulation of mannosyl, fucosyl receptor activity in vitro by lymphokines, gamma and alpha interferons, and dexamethasone.

    PubMed Central

    Mokoena, T; Gordon, S

    1985-01-01

    We describe a sensitive assay to measure immune activation of human macrophages in cell culture. Freshly isolated blood monocytes from normal subjects lack the ability to endocytose and degrade mannosyl-terminated glycoconjugates via specific receptors, but acquired this activity after cultivation in autologous serum for approximately 3 d. Addition of specific antigen, purified protein derivative, or T cell mitogens to mononuclear cells prevented the appearance of macrophage mannosyl receptor activity and lymphokine, gamma-, and alpha-interferons selectively down-regulated receptor activity in monocyte-macrophage targets. The effects of antigen challenge and gamma-interferon on mannosyl receptors can be prevented by 10(-8) M dexamethasone. Dexamethasone also inhibited release of another macrophage activation marker, plasminogen activator, which was increased by both gamma- and alpha-interferons. These studies show that activation of human macrophages is regulated by opposing actions of lymphokines and glucocorticoids. PMID:2579101

  6. MiR-320a inhibits gastric carcinoma by targeting activity in the FoxM1-P27KIP1 axis

    PubMed Central

    Pan, Jianyong; Geng, Xue; Li, Lupeng; Wu, Jing; Song, Ping; Wang, Ying; Liu, Jilan; Wang, Lixiang

    2016-01-01

    MicroRNAs (miRNAs) regulate tumorigenesis by inhibiting gene expression. In this study, we showed that miR-320a expression is decreased in human gastric cancer tissues and correlates inversely with expression of FoxM1, a key cell cycle regulator involved in gastric carcinoma. By contrast, the expression of P27KIP1, a downstream effector of FoxM1, correlates positively with miR-320a levels. Luciferase assays indicate that miR-320a suppresses FoxM1 expression, and in vitro recovery tests using FoxM1 siRNA indicate miR-320a inhibits gastric cancer cell proliferation by suppressing activity in the FoxM1-P27KIP1 axis. In vivo, nude mice injected with BGC-823 gastric cancer cells expressing a miR-320a inhibitor exhibit faster tumor growth than mice injected with control cells. Analysis of FoxM1 and P27KIP1 expression in tumor tissues indicates that miR-320a suppression increases the tumor growth by enhancing FoxM1-P27KIP1 signaling. These results thus reveal the crucial role played by miR-320a in limiting gastric carcinoma by directly targeting FoxM1- P27KIP1 axis. PMID:27086911

  7. IL-33 Priming Enhances Peritoneal Macrophage Activity in Response to Candida albicans.

    PubMed

    Tran, Vuvi G; Cho, Hong R; Kwon, Byungsuk

    2014-08-01

    IL-33 is a member of the IL-1 cytokine family and plays a role in the host defense against bacteria, viruses, and fungi. In this study, we investigated the function of IL-33 and its receptor in in vitro macrophage responses to Candida albicans. Our results demonstrate that pre-sensitization of isolated peritoneal macrophages with IL-33 enhanced their pro-inflammatory cytokine production and phagocytic activity in response to C. albicans. These macrophage activities were entirely dependent on the ST2-MyD88 signaling pathway. In addition, pre-sensitization with IL-33 also increased ROS production and the subsequent killing ability of macrophages following C. albicans challenge. These results indicate that IL-33 may increase anti-fungal activity against Candida through macrophage-mediated resistance mechanisms. PMID:25177252

  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. Mitogen-Activated Protein Kinases and Mitogen Kinase Phosphatase 1: A Critical Interplay in Macrophage Biology.

    PubMed

    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

  10. 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.

  11. 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.

  12. Metabolic Reprograming in Macrophage Polarization

    PubMed Central

    Galván-Peña, Silvia; O’Neill, Luke A. J.

    2014-01-01

    Studying the metabolism of immune cells in recent years has emphasized the tight link existing between the metabolic state and the phenotype of these cells. Macrophages in particular are a good example of this phenomenon. Whether the macrophage obtains its energy through glycolysis or through oxidative metabolism can give rise to different phenotypes. Classically activated or M1 macrophages are key players of the first line of defense against bacterial infections and are known to obtain energy through glycolysis. Alternatively activated or M2 macrophages on the other hand are involved in tissue repair and wound healing and use oxidative metabolism to fuel their longer-term functions. Metabolic intermediates, however, are not just a source of energy but can be directly implicated in a particular macrophage phenotype. In M1 macrophages, the Krebs cycle intermediate succinate regulates HIF1α, which is responsible for driving the sustained production of the pro-inflammatory cytokine IL1β. In M2 macrophages, the sedoheptulose kinase carbohydrate kinase-like protein is critical for regulating the pentose phosphate pathway. The potential to target these events and impact on disease is an exciting prospect. PMID:25228902

  13. Metformin Inhibits Advanced Glycation End Products-Induced Inflammatory Response in Murine Macrophages Partly through AMPK Activation and RAGE/NFκB Pathway Suppression

    PubMed Central

    Zhou, Zhong'e; Tang, Yong; Chen, Chengjun; Lu, Yi; Liu, Liang

    2016-01-01

    Advanced glycation end products (AGEs) are major inflammatory mediators in diabetes, affecting atherosclerosis progression via macrophages. Metformin slows diabetic atherosclerosis progression through mechanisms that remain to be fully elucidated. The present study of murine bone marrow derived macrophages showed that (1) AGEs enhanced proinflammatory cytokines (interleukin-1β (IL-1β), IL-6, and tumor necrosis factor-α (TNF-α)) mRNA expression, RAGE expression, and NFκB activation; (2) metformin pretreatment inhibited AGEs effects and AGEs-induced cluster designation 86 (CD86) (M1 marker) expression, while promoting CD206 (M2 marker) surface expression and anti-inflammatory cytokine (IL-10) mRNA expression; and (3) the AMPK inhibitor, Compound C, attenuated metformin effects. In conclusion, metformin inhibits AGEs-induced inflammatory response in murine macrophages partly through AMPK activation and RAGE/NFκB pathway suppression. PMID:27761470

  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. 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

  16. Morphine Modulates Interleukin-4- or Breast Cancer Cell-induced Pro-metastatic Activation of Macrophages.

    PubMed

    Khabbazi, Samira; Goumon, Yannick; Parat, Marie-Odile

    2015-01-01

    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.

  17. Ultrastructural studies of the killing of schistosomula of Schistosoma mansoni by activated macrophages in vitro.

    PubMed

    McLaren, D J; James, S L

    1985-05-01

    Immunologically activated murine macrophages have been shown elsewhere to kill skin stage schistosomula of Schistosoma mansoni in vitro, in a manner analogous to the extracellular killing of tumour cell targets. In this study, the kinetics of the interaction between activated macrophages and larval targets and the resultant ultrastructural changes in parasite morphology that culminated in death have been analysed in detail. Unlike granulocyte-mediated schistosomular killing, macrophage-mediated cytotoxicity did not appear to be directed against the surface tissues of the parasite. Macrophages adhered only transiently following initiation of the cultures, yet changes in the subtegumental mitochondria and muscle cells of the larva were detected within the first hour of incubation. Progressive internal disorganisation followed rapidly, but the tegument and tegumental outer membrane remained intact, to form a 'shell' that maintained the general shape of the parasite. Such changes were recognised irrespective of whether the effector cell population comprised peritoneal macrophages activated by lymphokine treatment in vitro, or by infection with Mycobacterium bovis (strain BCG), or S. mansoni in vivo. That macrophages rather than contaminating granulocytes or lymphocytes, had mediated the observed damage was demonstrated by the use of a lymphokine treated macrophage cell line, IC-21. The observation that macrophage cytotoxicity is directed against internal organelles rather than the tegumental outer membrane of this multicellular target, may help to elucidate the general mechanism of extracellular killing by these cells. PMID:3892433

  18. 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.

  19. Substrate Stiffness Regulates Proinflammatory Mediator Production through TLR4 Activity in Macrophages

    PubMed Central

    Previtera, Michelle L.; Sengupta, Amitabha

    2015-01-01

    Clinical data show that disease adversely affects tissue elasticity or stiffness. While macrophage activity plays a critical role in driving disease pathology, there are limited data available on the effects of tissue stiffness on macrophage activity. In this study, the effects of substrate stiffness on inflammatory mediator production by macrophages were investigated. Bone marrow–derived macrophages were grown on polyacrylamide gels that mimicked the stiffness of a variety of soft biological tissues. Overall, macrophages grown on soft substrates produced less proinflammatory mediators than macrophages grown on stiff substrates when the endotoxin LPS was added to media. In addition, the pathways involved in stiffness–regulated proinflammation were investigated. The TLR4 signaling pathway was examined by evaluating TLR4, p–NF–κB p65, MyD88, and p–IκBα expression as well as p–NF–κB p65 translocation. Expression and translocation of the various signaling molecules were higher in macrophages grown on stiff substrates than on soft substrates. Furthermore, TLR4 knockout experiments showed that TLR4 activity enhanced proinflammation on stiff substrates. In conclusion, these results suggest that proinflammatory mediator production initiated by TLR4 is mechanically regulated in macrophages. PMID:26710072

  20. Substrate Stiffness Regulates Proinflammatory Mediator Production through TLR4 Activity in Macrophages.

    PubMed

    Previtera, Michelle L; Sengupta, Amitabha

    2015-01-01

    Clinical data show that disease adversely affects tissue elasticity or stiffness. While macrophage activity plays a critical role in driving disease pathology, there are limited data available on the effects of tissue stiffness on macrophage activity. In this study, the effects of substrate stiffness on inflammatory mediator production by macrophages were investigated. Bone marrow-derived macrophages were grown on polyacrylamide gels that mimicked the stiffness of a variety of soft biological tissues. Overall, macrophages grown on soft substrates produced less proinflammatory mediators than macrophages grown on stiff substrates when the endotoxin LPS was added to media. In addition, the pathways involved in stiffness-regulated proinflammation were investigated. The TLR4 signaling pathway was examined by evaluating TLR4, p-NF-κB p65, MyD88, and p-IκBα expression as well as p-NF-κB p65 translocation. Expression and translocation of the various signaling molecules were higher in macrophages grown on stiff substrates than on soft substrates. Furthermore, TLR4 knockout experiments showed that TLR4 activity enhanced proinflammation on stiff substrates. In conclusion, these results suggest that proinflammatory mediator production initiated by TLR4 is mechanically regulated in macrophages. PMID:26710072

  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. Pterins inhibit nitric oxide synthase activity in rat alveolar macrophages.

    PubMed Central

    Jorens, P. G.; van Overveld, F. J.; Bult, H.; Vermeire, P. A.; Herman, A. G.

    1992-01-01

    1. The synthesis of nitrite and citrulline from L-arginine by immune-stimulated rat alveolar macrophages and the modulation of this synthesis were studied. 2,4-Diamino-6-hydroxypyrimidine (DAHP), 6R-5,6,7,8-tetrahydro-L-biopterin (BH4) and L-sepiapterin were potent inhibitors of the recombinant interferon-gamma induced production of nitrogen oxides in intact cultured cells with I50 values for BH4 and L-sepiapterin of approximately 10 microM. They were equally effective in inhibiting the induced production of citrulline. This inhibitory effect was concentration-dependent for all three modulators investigated. 2. The inhibitory effects were not dependent on incubation times of either 24 or 48 h, on the immune-stimulus used (lipopolysaccharide, interferon-gamma), or whether these stimuli were added during or after the induction period. 3. Pterin-6-carboxylic acid (PCA), which cannot be converted into BH4, and methotrexate (MTX), which inhibits dihydrofolatereductase but not de novo biosynthesis of BH4, did not change the production of nitrite. 4. The data indicate that DAHP, an inhibitor of the de novo biosynthesis of the co-factor BH4, blocks the nitric oxide synthase activity in intact cells. Since the pterins BH4 and L-sepiapterin blocked the L-arginine dependent production of nitrite and citrulline, the activity of nitric oxide synthase in phagocytic cells may be regulated by metabolic endproducts of the de novo biosynthesis of BH4. PMID:1281717

  3. The active enhancer network operated by liganded RXR supports angiogenic activity in macrophages

    PubMed Central

    Daniel, Bence; Hah, Nasun; Horvath, Attila; Czimmerer, Zsolt; Poliska, Szilard; Gyuris, Tibor; Keirsse, Jiri; Gysemans, Conny; Van Ginderachter, Jo A.; Balint, Balint L.; Evans, Ronald M.; Barta, Endre; Nagy, Laszlo

    2014-01-01

    RXR signaling is predicted to have a major impact in macrophages, but neither the biological consequence nor the genomic basis of its ligand activation is known. Comprehensive genome-wide studies were carried out to map liganded RXR-mediated transcriptional changes, active binding sites, and cistromic interactions in the context of the macrophage genome architecture. The macrophage RXR cistrome has 5200 genomic binding sites, which are not impacted by ligand. Active enhancers are characterized by PU.1 binding, an increase of enhancer RNA, and P300 recruitment. Using these features, 387 liganded RXR-bound enhancers were linked to 226 genes, which predominantly reside in CTCF/cohesin-limited functional domains. These findings were molecularly validated using chromosome conformation capture (3C) and 3C combined with sequencing (3C-seq), and we show that selected long-range enhancers communicate with promoters via stable or RXR-induced loops and that some of the enhancers interact with each other, forming an interchromosomal network. A set of angiogenic genes, including Vegfa, has liganded RXR-controlled enhancers and provides the macrophage with a novel inducible program. PMID:25030696

  4. 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

  5. Interferon-γ regulates cellular metabolism and mRNA translation to potentiate macrophage activation.

    PubMed

    Su, Xiaodi; Yu, Yingpu; Zhong, Yi; Giannopoulou, Eugenia G; Hu, Xiaoyu; Liu, Hui; Cross, Justin R; Rätsch, Gunnar; Rice, Charles M; Ivashkiv, Lionel B

    2015-08-01

    Interferon-γ (IFN-γ) primes macrophages for enhanced microbial killing and inflammatory activation by Toll-like receptors (TLRs), but little is known about the regulation of cell metabolism or mRNA translation during this priming. We found that IFN-γ regulated the metabolism and mRNA translation of human macrophages by targeting the kinases mTORC1 and MNK, both of which converge on the selective regulator of translation initiation eIF4E. Physiological downregulation of mTORC1 by IFN-γ was associated with autophagy and translational suppression of repressors of inflammation such as HES1. Genome-wide ribosome profiling in TLR2-stimulated macrophages showed that IFN-γ selectively modulated the macrophage translatome to promote inflammation, further reprogram metabolic pathways and modulate protein synthesis. These results show that IFN-γ-mediated metabolic reprogramming and translational regulation are key components of classical inflammatory macrophage activation.

  6. 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. PMID:16479545

  7. Dysfunctional CFTR alters the bactericidal activity of human macrophages against Pseudomonas aeruginosa.

    PubMed

    Del Porto, Paola; Cifani, Noemi; Guarnieri, Simone; Di Domenico, Enea Gino; Mariggiò, Maria A; Spadaro, Francesca; Guglietta, Silvia; Anile, Marco; Venuta, Federico; Quattrucci, Serena; Ascenzioni, Fiorentina

    2011-01-01

    Chronic inflammation of the lung, as a consequence of persistent bacterial infections by several opportunistic pathogens represents the main cause of mortality and morbidity in cystic fibrosis (CF) patients. Mechanisms leading to increased susceptibility to bacterial infections in CF are not completely known, although the involvement of cystic fibrosis transmembrane conductance regulator (CFTR) in microbicidal functions of macrophages is emerging. Tissue macrophages differentiate in situ from infiltrating monocytes, additionally, mature macrophages from different tissues, although having a number of common activities, exhibit variation in some molecular and cellular functions. In order to highlight possible intrinsic macrophage defects due to CFTR dysfunction, we have focused our attention on in vitro differentiated macrophages from human peripheral blood monocytes. Here we report on the contribution of CFTR in the bactericidal activity against Pseudomonas aeruginosa of monocyte derived human macrophages. At first, by real time PCR, immunofluorescence and patch clamp recordings we demonstrated that CFTR is expressed and is mainly localized to surface plasma membranes of human monocyte derived macrophages (MDM) where it acts as a cAMP-dependent chloride channel. Next, we evaluated the bactericidal activity of P. aeruginosa infected macrophages from healthy donors and CF patients by antibiotic protection assays. Our results demonstrate that control and CF macrophages do not differ in the phagocytic activity when infected with P. aeruginosa. Rather, although a reduction of intracellular live bacteria was detected in both non-CF and CF cells, the percentage of surviving bacteria was significantly higher in CF cells. These findings further support the role of CFTR in the fundamental functions of innate immune cells including eradication of bacterial infections by macrophages.

  8. FoxM1 Drives a Feed-forward STAT3-activation Signaling Loop that Promotes the Self-renewal and Tumorigenicity of Glioblastoma Stem-like Cells

    PubMed Central

    Gong, Ai-hua; Wei, Ping; Zhang, Sicong; Yao, Jun; Yuan, Ying; Zhou, Ai-dong; Lang, Frederick F.; Heimberger, Amy B.; Rao, Ganesh; Huang, Suyun

    2015-01-01

    The growth factor PDGF controls the development of glioblastoma (GBM) but its contribution to the function of GBM stem-like cells (GSC) has been little studied. Here we report that the transcription factor FoxM1 promotes PDGFA-STAT3 signaling to drive GSC self-renewal and tumorigenicity. In GBM we found a positive correlation between expression of FoxM1 and PDGF-A. In GSC and mouse neural stem cells, FoxM1 bound to the PDGF-A promoter to upregulate PDGF-A expression, acting to maintain the stem-like qualities of GSC in part through this mechanism. Analysis of the human cancer genomic database TCGA revealed that GBM express higher levels of STAT3, a PDGF-A effector signaling molecule, as compared with normal brain. FoxM1 regulated STAT3 transcription through interactions with the β-catenin/TCF4 complex. FoxM1 deficiency inhibited PDGF-A and STAT3 expression in neural stem cells and GSC, abolishing their stem-like and tumorigenic properties. Further mechanistic investigations defined a FoxM1-PDGFA-STAT3 feed-forward pathway that was sufficient to confer stem-like properties to glioma cells. Collectively, our findings showed how FoxM1 activates expression of PDGF-A and STAT3 in a pathway required to maintain the self-renewal and tumorigenicity of glioma stem-like cells. PMID:25832656

  9. Antidepressant therapies inhibit inflammation and microglial M1-polarization.

    PubMed

    Kalkman, Hans O; Feuerbach, Dominik

    2016-07-01

    Macrophages and their counterparts in the central nervous system, the microglia, detect and subsequently clear microbial pathogens and injured tissue. These phagocytic cells alter and adapt their phenotype depending on their prime activity, i.e., whether they participate in acute defence against pathogenic organisms ('M1'-phenotype) or in clearing damaged tissues and performing repair activities ('M2'-phenotype). Stimulation of pattern recognition receptors by viruses (vaccines), bacterial membrane components (e.g., LPS), alcohol, or long-chain saturated fatty acids promotes M1-polarization. Vaccine or LPS administration to healthy human subjects can result in sickness symptoms and low mood. Alcohol abuse and abdominal obesity are recognized as risk factors for depression. In the M1-polarized form, microglia and macrophages generate reactive oxygen and nitrogen radicals to eradicate microbial pathogens. Inadvertently, also tetrahydrobiopterin (BH4) may become oxidized. This is an irreversible reaction that generates neopterin, a recognized biomarker for depression. BH4 is a critical cofactor for the synthesis of dopamine, noradrenaline, and serotonin, and its loss could explain some of the symptoms of depression. Based on these aspects, the suppression of M1-polarization would limit the inadvertent catabolism of BH4. In the current review, we evaluate the evidence that antidepressant treatments (monoamine reuptake inhibitors, PDE4 inhibitors, lithium, valproate, agomelatine, tianeptine, electroconvulsive shock, and vagus nerve stimulation) inhibit LPS-induced microglia/macrophage M1-polarization. Consequently, we propose that supplementation with BH4 could limit the reduction in central monoamine synthesis and might represent an effective treatment for depressed mood. PMID:27101921

  10. Antidepressant therapies inhibit inflammation and microglial M1-polarization.

    PubMed

    Kalkman, Hans O; Feuerbach, Dominik

    2016-07-01

    Macrophages and their counterparts in the central nervous system, the microglia, detect and subsequently clear microbial pathogens and injured tissue. These phagocytic cells alter and adapt their phenotype depending on their prime activity, i.e., whether they participate in acute defence against pathogenic organisms ('M1'-phenotype) or in clearing damaged tissues and performing repair activities ('M2'-phenotype). Stimulation of pattern recognition receptors by viruses (vaccines), bacterial membrane components (e.g., LPS), alcohol, or long-chain saturated fatty acids promotes M1-polarization. Vaccine or LPS administration to healthy human subjects can result in sickness symptoms and low mood. Alcohol abuse and abdominal obesity are recognized as risk factors for depression. In the M1-polarized form, microglia and macrophages generate reactive oxygen and nitrogen radicals to eradicate microbial pathogens. Inadvertently, also tetrahydrobiopterin (BH4) may become oxidized. This is an irreversible reaction that generates neopterin, a recognized biomarker for depression. BH4 is a critical cofactor for the synthesis of dopamine, noradrenaline, and serotonin, and its loss could explain some of the symptoms of depression. Based on these aspects, the suppression of M1-polarization would limit the inadvertent catabolism of BH4. In the current review, we evaluate the evidence that antidepressant treatments (monoamine reuptake inhibitors, PDE4 inhibitors, lithium, valproate, agomelatine, tianeptine, electroconvulsive shock, and vagus nerve stimulation) inhibit LPS-induced microglia/macrophage M1-polarization. Consequently, we propose that supplementation with BH4 could limit the reduction in central monoamine synthesis and might represent an effective treatment for depressed mood.

  11. Glucocorticoid-induced impairment of macrophage antimicrobial activity: mechanisms and dependence on the state of activation.

    PubMed

    Schaffner, A; Schaffner, T

    1987-01-01

    Experimental observations indicate that tissue macrophages deployed in great numbers at critical anatomic sites such as the liver, spleen, and lung are major targets for glucocorticoids compromising natural resistance of the host. Therapeutic concentrations of glucocorticoids appear to prevent destruction of microorganisms ingested by macrophages without interfering with phagocytosis, phagolysosomal fusion, and/or secretion of reactive oxygen intermediates. These findings indicate that at the cellular level the glucocorticoid target should be sought for in the nonoxidative armature of the phagocyte and that nonoxidative killing systems of resident tissue macrophages play an important role in natural resistance to opportunistic pathogens. Glucocorticoids do not prevent lymphokine-induced activation of oxidative killing systems. Thus, lymphokines such as interferon-gamma can restore the microbicidal activity of macrophages functionally impaired by glucocorticoids. Counterbalance of the suppressive effect of glucocorticoids by lymphokines might only be possible, however, for pathogens susceptible to oxidative killing and not for microorganisms that are more resistant to reactive oxygen intermediates such as Aspergillus spores and Nocardia, opportunists that appear to be particularly associated with hypercortisolism.

  12. Salicylate improves macrophage cholesterol homeostasis via activation of Ampk[S

    PubMed Central

    Fullerton, Morgan D.; Ford, Rebecca J.; McGregor, Chelsea P.; LeBlond, Nicholas D.; Snider, Shayne A.; Stypa, Stephanie A.; Day, Emily A.; Lhoták, Šárka; Schertzer, Jonathan D.; Austin, Richard C.; Kemp, Bruce E.; Steinberg, Gregory R.

    2015-01-01

    Atherosclerosis stems from imbalances in lipid metabolism and leads to maladaptive inflammatory responses. The AMP-activated protein kinase (Ampk) is a highly conserved serine/threonine kinase that regulates many aspects of lipid and energy metabolism, although its specific role in controlling macrophage cholesterol homeostasis remains unclear. We sought to address this question by testing the effects of direct Ampk activators in primary bone marrow-derived macrophages from Ampk β1-deficient (β1−/−) mice. Macrophages from Ampk β1−/− mice had enhanced lipogenic capacity and diminished cholesterol efflux, although cholesterol uptake was unaffected. Direct activation of Ampk β1 via salicylate (the unacetylated form of aspirin) or A-769662 (a small molecule activator), decreased the synthesis of FAs and sterols in WT but not Ampk β1−/− macrophages. In lipid-laden macrophages, Ampk activation decreased cholesterol content (foam cell formation) and increased cholesterol efflux to HDL and apoA-I, effects that occurred in an Ampk β1-dependent manner. Increased cholesterol efflux was also associated with increased gene expression of the ATP binding cassette transporters, Abcg1 and Abca1. Moreover, in vivo reverse cholesterol transport was suppressed in mice that received Ampk β1−/− macrophages compared with the WT control. Our data highlight the therapeutic potential of targeting macrophage Ampk with new or existing drugs for the possible reduction in foam cell formation during the early stages of atherosclerosis. PMID:25773887

  13. Investigation of macrophage polarization using bone marrow derived macrophages.

    PubMed

    Ying, Wei; Cheruku, Patali S; Bazer, Fuller W; Safe, Stephen H; Zhou, Beiyan

    2013-06-23

    The article describes a readily easy adaptive in vitro model to investigate macrophage polarization. In the presence of GM-CSF/M-CSF, hematopoietic stem/progenitor cells from the bone marrow are directed into monocytic differentiation, followed by M1 or M2 stimulation. The activation status can be tracked by changes in cell surface antigens, gene expression and cell signaling pathways.

  14. Murine Macrophages Secrete Interferon γ upon Combined Stimulation with Interleukin (IL)-12 and IL-18: A Novel Pathway of Autocrine Macrophage Activation

    PubMed Central

    Munder, Markus; Mallo, Moisés; Eichmann, Klaus; Modolell, Manuel

    1998-01-01

    Interferon (IFN)-γ, a key immunoregulatory cytokine, has been thought to be produced solely by activated T cells and natural killer cells. In this study, we show that murine bone marrow– derived macrophages (BMMΦ) secrete large amounts of IFN-γ upon appropriate stimulation. Although interleukin (IL)-12 and IL-18 alone induce low levels of IFN-γ mRNA transcripts, the combined stimulation of BMMΦ with both cytokines leads to the efficient production of IFN-γ protein. The macrophage-derived IFN-γ is biologically active as shown by induction of inducible nitric oxide synthase as well as upregulation of CD40 in macrophages. Our findings uncover a novel pathway of autocrine macrophage activation by demonstrating that the macrophage is not only a key cell type responding to IFN-γ but also a potent IFN-γ–producing cell. PMID:9625771

  15. Effect of dietary linseed oil on tumoricidal activity and eicosanoid production in murine macrophages.

    PubMed

    Hubbard, N E; Chapkin, R S; Erickson, K L

    1994-09-01

    Diets that contain high levels of n-3 fatty acids from fish oil have been shown to significantly effect macrophage cytolytic capacity, tumor necrosis factor alpha production and eicosanoid production. The present study was undertaken to determine whether n-3 fatty acids from vegetable origin [linseed oil (LIN)] would have the same effects on murine macrophage tumoricidal capacity and eicosanoid production as would fish oil. Mice were fed for three weeks diets that contained 10% (wt/wt) of either LIN, which is high in linolenic acid (18:3n-3), menhaden fish oil (MFO), which is high in eicosapentaenoic (20:5n-3) and docosahexaenoic (22:6n-3) acids, or safflower oil (SAF), which is high in linoleic acid (18:2n-6). In vivo- or in vitro-activated macrophages were assessed for select functions. As expected, macrophages from mice fed LIN and MFO produced significantly lower levels of both prostaglandins and leukotriene C4 when compared with macrophages from mice fed SAF. In addition, LIN and MFO macrophages were able to synthesize leuko-triene C5, which could not be produced by macrophages from mice fed SAF. The effects of LIN, however, were not as pronounced as those of MFO. With respect to specific functions, macrophages from mice fed LIN did not have altered cytolytic capacity when compared with macrophages from mice fed SAF and activated in vitro with either lipopolysaccharide (LPS) alone for 24 h or with LPS plus interferon gamma (IFN gamma) for 5 h. Diet did not significantly alter tumoricidal capacity of macrophages activated completely in vivo either.(ABSTRACT TRUNCATED AT 250 WORDS)

  16. Human cytomegalovirus and Epstein–Barr virus inhibit oral bacteria-induced macrophage activation and phagocytosis

    PubMed Central

    Lin, Y.-L.; Li, M.

    2016-01-01

    Introduction Periodontal disease is an inflammatory condition caused by periodontal microorganisms. Viruses such as human cytomegalovirus (HCMV) and Epstein–Barr virus (EBV) are associated with certain types of periodontal disease, but their roles in promoting the disease are unclear. Because both viruses infect human macrophages, cells which play key roles in the clearance of pathogenic bacteria, it is likely that the viruses alter the functional capacity of macrophages by inhibiting their defense mechanisms against invading pathogens. Methods Macrophages preinfected with HCMV or EBV were evaluated following stimulation by selected oral bacteria. Bacteria-induced macrophage activation was assayed by measuring the levels of tumor necrosis factor-α (TNF-α) produced in the media, and phagocytic activity was analysed by a phagocytosis assay with fluorescein isothiocyanate-labeled bacteria. The virus-infected macrophages were also subjected to semi-quantitative polymerase chain reaction to measure the expression of toll-like receptor 9, which is involved in the activation of phagocytosis-related pathways. Results Both HCMV and EBV significantly diminished the TNF-α production typically induced by oral bacteria, inhibited the phagocytic activity of macrophages, and downregulated the expression of toll-like receptor 9. Conclusion Infection by HCMV or EBV inhibits the functional ability of macrophages to respond to bacterial challenge, thereby suggesting their pathogenic role in the development of periodontal disease. PMID:19416455

  17. Macrophage activation: role of toll-like receptors, nitric oxide, and nuclear factor kappa B.

    PubMed

    Billack, Blase

    2006-10-15

    Macrophages play an important role in host-defense and inflammation. In response to an immune challenge, macrophages become activated and produce proinflammatory mediators that contribute to nonspecific immunity. The mediators released by activated macrophages include: superoxide anion; reactive nitrogen intermediates, such as nitric oxide and peroxynitrite; bioactive lipids; and cytokines. Although essential to the immune response, overproduction of certain macrophage-derived mediators during an immune challenge or inflammatory response can result in tissue injury and cellular death. The present report is focused on understanding some of the molecular mechanisms used by macrophages to produce reactive nitrogen intermediates in response to immunostimulatory agents such as heat shock protein 60 and bacterial lipopolysaccharide. The role of Toll-like receptors and transcription factors such as nuclear factor kappa B (NFkappaB) in the innate immune response is also described. A basic understanding of the underlying molecular mechanisms responsible for macrophage activation should serve as a foundation for novel drug development aimed at modulating macrophage activity.

  18. 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.

  19. C/EBPβ-Thr217 Phosphorylation Stimulates Macrophage Inflammasome Activation and Liver Injury

    PubMed Central

    Buck, Martina; Solis-Herruzo, Jose; Chojkier, Mario

    2016-01-01

    Amplification of liver injury is mediated by macrophages but the signaling by which the macrophage inflammasome enhances liver injury is not completely understood. The CCAAT/Enhancer Binding Protein-β (C/EBPβ) is a critical signaling molecule for macrophages because expression of a dominant inhibitor of C/EBPβ DNA-binding sites or a targeted deletion of C/EBPβ results in impaired macrophage differentiation. We reported that expression of the phosphorylation-mutant C/EBPβ-Glu217, which mimics phosphorylated C/EBPβ-Thr217, was sufficient to confer macrophage survival to Anthrax lethal toxin. Here, using primary hepatocytes, primary liver macrophages, dominant positive and negative transgenic mice of the C/EBPβ-Thr217 phosphoacceptor, macrophage ablation, and an inhibitory peptide of C/EBPβ-Thr217 phosphorylation, we determined that this phosphorylation is essential for the activation of the inflammasome in liver macrophages and for the hepatocyte apoptosis induced by hepatotoxins that results in liver injury. Similar findings were observed in the livers of patients with acute injury induced by Toxic Oil Syndrome. PMID:27067260

  20. C/EBPβ-Thr217 Phosphorylation Stimulates Macrophage Inflammasome Activation and Liver Injury.

    PubMed

    Buck, Martina; Solis-Herruzo, Jose; Chojkier, Mario

    2016-01-01

    Amplification of liver injury is mediated by macrophages but the signaling by which the macrophage inflammasome enhances liver injury is not completely understood. The CCAAT/Enhancer Binding Protein-β (C/EBPβ) is a critical signaling molecule for macrophages because expression of a dominant inhibitor of C/EBPβ DNA-binding sites or a targeted deletion of C/EBPβ results in impaired macrophage differentiation. We reported that expression of the phosphorylation-mutant C/EBPβ-Glu217, which mimics phosphorylated C/EBPβ-Thr217, was sufficient to confer macrophage survival to Anthrax lethal toxin. Here, using primary hepatocytes, primary liver macrophages, dominant positive and negative transgenic mice of the C/EBPβ-Thr217 phosphoacceptor, macrophage ablation, and an inhibitory peptide of C/EBPβ-Thr217 phosphorylation, we determined that this phosphorylation is essential for the activation of the inflammasome in liver macrophages and for the hepatocyte apoptosis induced by hepatotoxins that results in liver injury. Similar findings were observed in the livers of patients with acute injury induced by Toxic Oil Syndrome. PMID:27067260

  1. The response of macrophages to titanium particles is determined by macrophage polarization.

    PubMed

    Pajarinen, Jukka; Kouri, Vesa-Petteri; Jämsen, Eemeli; Li, Tian-Fang; Mandelin, Jami; Konttinen, Yrjö T

    2013-11-01

    Aseptic loosening of total joint replacements is driven by the reaction of macrophages to foreign body particles released from the implant. It was hypothesized that the macrophages' response to these particles is dependent, in addition to particle characteristics and contaminating biomolecules, on the state of macrophage polarization as determined by the local cytokine microenvironment. To test this hypothesis we differentiated M1 and M2 macrophages from human peripheral blood monocytes and compared their responses to titanium particles using genome-wide microarray analysis and a multiplex cytokine assay. In comparison to non-activated M0 macrophages, the overall chemotactic and inflammatory responses to titanium particles were greatly enhanced in M1 macrophages and effectively suppressed in M2 macrophages. In addition, the genome-wide approach revealed several novel, potentially osteolytic, particle-induced mediators, and signaling pathway analysis suggested the involvement of toll-like and nod-like receptor signaling in particle recognition. It is concluded that the magnitude of foreign body reaction caused by titanium particles is dependent on the state of macrophage polarization. Thus, by limiting the action of M1 polarizing factors, e.g. bacterial biofilm formation, in peri-implant tissues and promoting M2 macrophage polarization by biomaterial solutions or pharmacologically, it might be possible to restrict wear-particle-induced inflammation and osteolysis.

  2. Gallium arsenide modulates proteolytic cathepsin activities and antigen processing by macrophages.

    PubMed

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

    1998-09-01

    Gallium arsenide (GaAs) is a semiconductor utilized in the electronics industry. Chemical exposure of animals causes a local inflammatory reaction, but systemic immunosuppression. Mice were administered i.p. 200 mg/kg GaAs crystals or latex beads, or vehicle. Five days after exposure, splenic macrophages were defective, whereas thioglycolate-elicited peritoneal macrophages (PEC) were more efficient in processing the Ag, pigeon cytochrome c, than vehicle control macrophages. Various aspects of the MHC class II Ag-processing pathway were examined. Both macrophage populations normally presented a peptide fragment to the CD4+ T cells. Surface MHC class II expression on the PEC was up-regulated, but splenic cells had normal MHC class II expression. PEC had elevated levels of glutathione and cysteine, major physiologic reducing thiols. However, the cysteine content of splenic macrophages was diminished. Proteolytic activities of aspartyl cathepsin D, and thiol cathepsins B and L were decreased significantly in splenic macrophages. On the other hand, thiol cathepsin activities were increased selectively in PEC. Latex bead-exposed PEC were not more potent APC, and their thiol cathepsin activities were unchanged, indicating that phagocytosis and nonspecific irritation were not responsible. The phenotype of PEC directly exposed to GaAs mirrored cytokine-activated macrophages, in contrast to splenic macrophages from a distant site. Therefore, GaAs exposure differentially modulated cathepsin activities in splenic macrophages and PEC, which correlated with their Ag-processing efficiency. Perhaps such distinct alterations may contribute to the local inflammation and systemic immunotoxicity caused by chemical exposure.

  3. 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

  4. 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

  5. Classically and alternatively activated macrophages contribute to tissue remodelling after myocardial infarction

    PubMed Central

    Troidl, C; Möllmann, H; Nef, H; Masseli, F; Voss, S; Szardien, S; Willmer, M; Rolf, A; Rixe, J; Troidl, K; Kostin, S; Hamm, C; Elsässer, A

    2009-01-01

    An important goal in cardiology is to minimize myocardial necrosis and to support a discrete but resilient scar formation after myocardial infarction (MI). Macrophages are a type of cells that influence cardiac remodelling during MI. Therefore, the goal of the present study was to investigate their transcriptional profile and to identify the type of activation during scar tissue formation. Ligature of the left anterior descending coronary artery was performed in mice. Macrophages were isolated from infarcted tissue using magnetic cell sorting after 5 days. The total RNA of macrophages was subjected to microarray analysis and compared with RNA from MI and LV-control. mRNA abundance of relevant targets was validated by quantitative real-time PCR 2, 5 and 10 days after MI (qRT-PCR). Immunohistochemistry was performed to localize activation type-specific proteins. The genome scan revealed 68 targets predominantly expressed by macrophages after MI. Among these targets, an increased mRNA abundance of genes, involved in both the classically (tumour necrosis factor α, interleukin 6, interleukin 1β) and the alternatively (arginase 1 and 2, mannose receptor C type 1, chitinase 3-like 3) activated phenotype of macrophages, was found 5 days after MI. This observation was confirmed by qRT-PCR. Using immunohistochemistry, we confirmed that tumour necrosis factor α, representing the classical activation, is strongly transcribed early after ligature (2 days). It was decreased after 5 and 10 days. Five days after MI, we found a fundamental change towards alternative activation of macrophages with up-regulation of arginase 1. Our results demonstrate that macrophages are differentially activated during different phases of scar tissue formation after MI. During the early inflammatory phase, macrophages are predominantly classically activated, whereas their phenotype changes during the important transition from inflammation to scar tissue formation into an alternatively activated

  6. Macrophage activation syndrome in a newborn infant born to a mother with autoimmune disease.

    PubMed

    Park, J H; Kim, S H; Kim, H J; Lee, S J; Jeong, D C; Kim, S Y

    2015-02-01

    Macrophage activation syndrome (MAS) is a complication of rheumatic disorders characterized by cytopenia, multiple organ dysfunction and coagulopathy associated with an inappropriate activation of macrophage. In neonatal lupus erythematosus, MAS is rare but fatal, requiring early diagnosis and treatment for optimal outcome. We report a case of MAS in a neonate born to a mother with autoimmune disease, improved by treatment with steroid, intravenous immunoglobulin and cyclosporine.

  7. Enhancing effect of oxygen radical scavengers on murine macrophage anticryptococcal activity through production of nitric oxide

    PubMed Central

    TOHYAMA, M.; KAWAKAMI, K.; FUTENMA, M.; SAITO, A.

    1996-01-01

    We examined the roles of reactive nitrogen intermediates (RNI) and reactive oxygen intermediates (ROI) in interferon-gamma (IFN-γ)-induced cryptococcostatic activity of murine peritoneal macrophages using NG-monomethyl-L-arginine (L-NMMA), a competitive inhibitor of RNI synthesis, and superoxide dismutase (SOD) and catalase, oxygen radical scavengers. IFN-γ-activated macrophages produced nitric oxide (NO) in a dose-dependent manner, as measured by increased nitrite concentration in the culture supernatant. IFN-γ also enhanced the suppressive effect on cryptococcal growth in a similar dose-dependent manner. The induction of killing activity and NO production by an optimal dose of IFN-γ (100 U/ml) was virtually suppressed by 500 μM L-NMMA. These results confirmed the importance of the RNI-mediated effector mechanism in anticryptococcal activity of macrophages. SOD and catalase significantly enhanced the cryptococcostatic activity of macrophages induced by a suboptimal dose of IFN-γ (20 U/ml). The augmenting effect of these reagents was mediated by NO, since they potentiated the production of NO by macrophages and their effects were totally blocked by L-NMMA. Our results indicate that the IFN-γ-induced anticryptococcal activity of macrophages is dependent mostly on RNI, and suggest that the ROI system down-regulates the effector mechanism for cryptococcostasis by suppressing the RNI system. PMID:8608643

  8. Enhanced resistance against Listeria monocytogenes at an early phase of primary infection in pregnant mice: activation of macrophages during pregnancy.

    PubMed Central

    Watanabe, Y; Mitsuyama, M; Sano, M; Nakano, H; Nomoto, K

    1986-01-01

    We investigated the pregnancy-induced changes in macrophage activity which are important in the expression of host defense against infections. Several macrophage functions were examined by using Listeria monocytogenes. In pregnant mice, prolonged survival and enhanced in vivo elimination of bacteria were observed in the early phase of primary infection. Functions of peritoneal macrophages, including in vitro phagocytosis intracellular killing, glucose consumption, generation of superoxide anion, and intracellular beta-glucuronidase activity were shown to be enhanced in pregnant mice. These findings indicate that pregnancy enhances macrophage functions qualitatively. Possible mechanisms for this enhancement and the significance of macrophage activation for pregnant hosts are discussed. PMID:3011673

  9. Tumor cell-activated CARD9 signaling contributes to metastasis-associated macrophage polarization.

    PubMed

    Yang, M; Shao, J-H; Miao, Y-J; Cui, W; Qi, Y-F; Han, J-H; Lin, X; Du, J

    2014-08-01

    Macrophages are critical immune effector cells of the tumor microenvironment that promote seeding, extravasation and persistent growth of tumor cells in primary tumors and metastatic sites. Tumor progression and metastasis are affected by dynamic changes in the specific phenotypes of macrophage subpopulations; however, the mechanisms by which tumor cells modulate macrophage polarization remain incompletely understood. Caspase recruitment domain-containing protein 9 (CARD9) is a central adaptor protein of innate immune responses to extracellular pathogens. We report that increased CARD9 expression is primarily localized in infiltrated macrophages and significantly associated with advanced histopathologic stage and the presence of metastasis. Using CARD9-deficient (CARD9(-/-)) mice, we show that bone marrow-derived CARD9 promotes liver metastasis of colon carcinoma cells. Mechanistic studies reveal that CARD9 contributes to tumor metastasis by promoting metastasis-associated macrophage polarization through activation of the nuclear factor-kappa B signaling pathway. We further demonstrate that tumor cell-secreted vascular endothelial growth factor facilitates spleen tyrosine kinase activation in macrophages, which is necessary for formation of the CARD9-B-cell lymphoma/leukemia 10-mucosa-associated lymphoid tissue lymphoma translocation protein 1 complex. Taken together, our results indicating that CARD9 is a regulator of metastasis-associated macrophages will lead to new insights into evolution of the microenvironments supporting tumor metastasis, thereby providing targets for anticancer therapies.

  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. Enhancement of Anti-Inflammatory Activity of Curcumin Using Phosphatidylserine-Containing Nanoparticles in Cultured Macrophages

    PubMed Central

    Wang, Ji; Kang, Yu-Xia; Pan, Wen; Lei, Wan; Feng, Bin; Wang, Xiao-Juan

    2016-01-01

    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. PMID:27331813

  12. Trypsin, Tryptase, and Thrombin Polarize Macrophages towards a Pro-Fibrotic M2a Phenotype

    PubMed Central

    White, Michael J. V.; Gomer, Richard H.

    2015-01-01

    For both wound healing and the formation of a fibrotic lesion, circulating monocytes enter the tissue and differentiate into fibroblast-like cells called fibrocytes and pro-fibrotic M2a macrophages, which together with fibroblasts form scar tissue. Monocytes can also differentiate into classically activated M1 macrophages and alternatively activated M2 macrophages. The proteases thrombin, which is activated during blood clotting, and tryptase, which is released by activated mast cells, potentiate fibroblast proliferation and fibrocyte differentiation, but their effect on macrophages is unknown. Here we report that thrombin, tryptase, and the protease trypsin bias human macrophage differentiation towards a pro-fibrotic M2a phenotype expressing high levels of galectin-3 from unpolarized monocytes, or from M1 and M2 macrophages, and that these effects appear to operate through protease-activated receptors. These results suggest that proteases can initiate scar tissue formation by affecting fibroblasts, fibrocytes, and macrophages. PMID:26407067

  13. 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.

  14. 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

  15. Murine cytotoxic activated macrophages inhibit aconitase in tumor cells. Inhibition involves the iron-sulfur prosthetic group and is reversible.

    PubMed

    Drapier, J C; Hibbs, J B

    1986-09-01

    Previous studies show that cytotoxic activated macrophages cause inhibition of DNA synthesis, inhibition of mitochondrial respiration, and loss of intracellular iron from tumor cells. Here we examine aconitase, a citric acid cycle enzyme with a catalytically active iron-sulfur cluster, to determine if iron-sulfur clusters are targets for activated macrophage-induced iron removal. Results show that aconitase activity declines dramatically in target cells after 4 h of co-cultivation with activated macrophages. Aconitase inhibition occurs simultaneously with arrest of DNA synthesis, another early activated macrophage-induced metabolic change in target cells. Dithionite partially prevents activated macrophage induced aconitase inhibition. Furthermore, incubation of injured target cells in medium supplemented with ferrous ion plus a reducing agent causes near-complete reconstitution of aconitase activity. The results show that removal of a labile iron atom from the [4Fe-4S] cluster, by a cytotoxic activated macrophage-mediated mechanism, is causally related to aconitase inhibition. PMID:3745439

  16. 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 ...

  17. 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

  18. Critical Role of Methylglyoxal and AGE in Mycobacteria-Induced Macrophage Apoptosis and Activation

    PubMed Central

    Rachman, Helmy; Kim, Nayoung; Ulrichs, Timo; Baumann, Sven; Pradl, Lydia; Eddine, Ali Nasser; Bild, Matthias; Rother, Marion; Kuban, Ralf-Jürgen; Lee, Jong Seok; Hurwitz, Robert; Brinkmann, Volker; Kosmiadi, George A.; Kaufmann, Stefan H.E.

    2006-01-01

    Apoptosis and activation of macrophages play an important role in the host response to mycobacterial infection involving TNF-α as a critical autocrine mediator. The underlying mechanisms are still ill-defined. Here, we demonstrate elevated levels of methylglyoxal (MG), a small and reactive molecule that is usually a physiological product of various metabolic pathways, and advanced glycation end products (AGE) during mycobacterial infection of macrophages, leading to apoptosis and activation of macrophages. Moreover, we demonstrate abundant AGE in pulmonary lesions of tuberculosis (TB) patients. Global gene expression profiling of MG-treated macrophages revealed a diverse spectrum of functions induced by MG, including apoptosis and immune response. Our results not only provide first evidence for the involvement of MG and AGE in TB, but also form a basis for novel intervention strategies against infectious diseases in which MG and AGE play critical roles. PMID:17183656

  19. 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

  20. Observation and modelling of main-sequence star chromospheres - XII. Two-component model chromospheres for five active dM1e stars

    NASA Astrophysics Data System (ADS)

    Houdebine, E. R.

    2009-08-01

    We aim to constrain the Hα, CaII H and CaII K profiles from quiescent and active regions on active dM1e stars. A preliminary analysis of all the data available for dM1e stars shows that the Hα/CaII equivalent width (EW) ratio varies by up to a factor of 7 for different stars in our sample. We find that spectroscopic binaries have a significantly smaller ratio than single dM1e stars. We also find that the pre-main-sequence stars Gl 616.2, GJ 1264 and Gl 803 have a ratio lower than main-sequence single dM1e stars. These differences imply that different chromospheric structures are present on different stars, notably the temperature minimum must decrease with an increasing Hα/CaII EW ratio. For these reasons, it is impossible to reproduce all observations with only one grid of model chromospheres. We show that the grid of model chromospheres of Paper VI is adequate to describe the physical conditions that prevail in the chromospheres of spectroscopic binaries and pre-main-sequence M1e stars, but not for the conditions in single dM1e stars. One or more additional grids of model chromospheres will be necessary to reproduce all observations. We use the method developed in Paper XI in this series, in order to build two-component model chromospheres for five M1e field stars: FF And A, FF And B, GJ 1264, AU Mic and Gl 815A. Our solutions provide an exact match of the Hα and the mean CaII H & K EWs within measurement uncertainties. We compare the theoretical profiles and the observed profiles of Hα and the CaII H & K resonance lines. On the one hand, our fits to the CaII lines are reasonably good. On the other hand, our models tend to produce Hα profiles with a central absorption that is too deep. This suggests that the column mass at the transition region for plages is underestimated, but this would imply that the contrast factor between quiescent and active regions in the CaII lines is larger than 5. We find that, except in the cases of FF And A and AU Mic, the total

  1. Role of activation in alveolar macrophage-mediated suppression of the plaque-forming cell response.

    PubMed Central

    Mbawuike, I N; Herscowitz, H B

    1988-01-01

    Alveolar macrophages (AM) are highly suppressive of the in vitro plaque-forming cell (PFC) response of spleen cells obtained from mice primed with sheep erythrocytes. Comparison of macrophage populations obtained from disparate anatomical sites revealed that although in both cases there was a cell-concentration-dependent suppression of the PFC response, resident AM or AM activated as a result of intravenous injection of Mycobacterium bovis BCG were equally suppressive at the doses examined. Although there was a similar dose-dependent suppression with peritoneal macrophages, BCG-activated cells were more suppressive of the PFC response than were resident cells. In contrast, splenic macrophages at comparable concentrations were not at all suppressive. Resident AM exhibited significantly lower levels of 5'-nucleotidase activity than did resident peritoneal macrophages. Macrophage-mediated suppression of the in vitro PFC response could not be attributed to the release of toxic oxygen metabolites (H2O2, O2- ,and .OH) or prostaglandins, since the addition of catalase, superoxide dismutase, 2-mercaptoethanol, or indomethacin did not completely reverse suppression. These results suggest that the lung microenvironment may maintain AM in an activated state which contributes to their potential immunoregulatory functions. PMID:2830191

  2. ROS-Responsive Activatable Photosensitizing Agent for Imaging and Photodynamic Therapy of Activated Macrophages

    PubMed Central

    Kim, Hyunjin; Kim, Youngmi; Kim, In-Hoo; Kim, Kyungtae; Choi, Yongdoo

    2014-01-01

    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. PMID:24396511

  3. Hydroxysafflor yellow A attenuates ischemia/reperfusion-induced liver injury by suppressing macrophage activation

    PubMed Central

    Jiang, Shujun; Shi, Zhen; Li, Changyong; Ma, Chunlei; Bai, Xianyong; Wang, Chaoyun

    2014-01-01

    Hydroxysafflor yellow A (HSYA), a major constituent in the hydrophilic fraction of the safflower plant, can retard the progress of hepatic fibrosis. However, the anti-inflammatory properties and the underlying mechanisms of HSYA on I/R-induced acute liver injury are unknown. Inhibiting macrophage activation is a potential strategy to treat liver ischemia/reperfusion (I/R) injury. In this study, we investigated the therapeutic effect of HSYA on liver I/R injury and the direct effect of HSYA on macrophage activation following inflammatory conditions. The therapeutic effects of HSYA on I/R injury were tested in vivo using a mouse model of segmental (70%) hepatic ischemia. The mechanisms of HSYA were examined in vitro by evaluating migration and the cytokine expression profile of the macrophage cell line RAW264.7 exposed to acute hypoxia and reoxygenation (H/R). Results showed that mice pretreated with HSYA had reduced serum transaminase levels, attenuated inflammation and necrosis, reduced expression of inflammatory cytokines, and less macrophage recruitment following segmental hepatic ischemia. In vitro HSYA pretreated RAW264.7 macrophages displayed reduced migratory response and produced less inflammatory cytokines. In addition, HSYA pretreatment down-regulated the expression of matrix matalloproteinase-9 and reactive oxygen species, and inhibited NF-κB activation and P38 phosphorylation in RAW264.7 cells. Thus, these data suggest that HSYA can reduce I/R-induced acute liver injury by directly attenuating macrophage activation under inflammatory conditions. PMID:24966974

  4. Mutation of the Theiler’s virus leader protein zinc-finger domain impairs apoptotic activity in murine macrophages

    PubMed Central

    Son, Kyung-No; Liang, Zhiguo; Lipton, Howard L.

    2014-01-01

    The Theiler’s murine encephalomyelitis virus (TMEV) leader (L) protein zinc-finger domain was mutated to study its role in cell death in infection of the murine macrophage cell line M1-D, revealing that an intact zinc-finger domain is required for full apoptotic activity. A functional L zinc-finger domain was also required for activation of p38 MAPK that results in phosphorylation and activation of p53, and in turn, alteration of the conformation of the anti-apoptotic proteins Puma and Mcl-1, leading to the release of pro-apoptotic Bax and apoptosis through the intrinsic pathway. TMEV infection also inhibits host protein synthesis, a stress shown by others to induce apoptosis. Since inhibition of host protein synthesis follows rather than precedes activation of MKK3/6 and p38, it seems less likely that it triggers of apoptosis in infected cells. Finally, we showed that the levels of reactive oxygen species following infection were consistent with apoptotic rather than necrotic cell death. Thus, these experiments support an important role for the TMEV L protein zinc-finger domain in apoptosis in an infected murine macrophage line. PMID:24036175

  5. Mutation of the Theiler's virus leader protein zinc-finger domain impairs apoptotic activity in murine macrophages.

    PubMed

    Son, Kyung-No; Liang, Zhiguo; Lipton, Howard L

    2013-11-01

    The Theiler's murine encephalomyelitis virus (TMEV) leader (L) protein zinc-finger domain was mutated to study its role in cell death in infection of the murine macrophage cell line M1-D, revealing that an intact zinc-finger domain is required for full apoptotic activity. A functional L zinc-finger domain was also required for activation of p38 MAPK that results in phosphorylation and activation of p53, and in turn, alteration of the conformation of the anti-apoptotic proteins Puma and Mcl-1, leading to the release of pro-apoptotic Bax and apoptosis through the intrinsic pathway. TMEV infection also inhibits host protein synthesis, a stress shown by others to induce apoptosis. Since inhibition of host protein synthesis follows rather than precedes activation of MKK3/6 and p38, it seems less likely that it triggers apoptosis in infected cells. Finally, we showed that the levels of reactive oxygen species following infection were consistent with apoptotic rather than necrotic cell death. Thus, these experiments support an important role for the TMEV L protein zinc-finger domain in apoptosis in an infected murine macrophage line.

  6. Exposure to Diesel Exhaust Particle Extracts (DEPe) Impairs Some Polarization Markers and Functions of Human Macrophages through Activation of AhR and Nrf2

    PubMed Central

    Jaguin, Marie; Fardel, Olivier; Lecureur, Valérie

    2015-01-01

    Macrophages (MΦ), well-known to play an important role in immune response, also respond to environmental toxic chemicals such as diesel exhaust particles (DEP). Potential effects of DEPs towards MΦ polarization, a key hall-mark of MΦ physiology, remain however poorly documented. This study was therefore designed to evaluate the effects of a reference DEP extract (DEPe) on human MΦ polarization. Human blood monocytes-derived MΦ were incubated with IFNγ+LPS or IL-4 to obtain M1 and M2 subtypes, respectively; a 24 h exposure of polarizing MΦ to 10 μg/ml DEPe was found to impair expression of some macrophagic M1 and M2 markers, without however overall inhibition of M1 and M2 polarization processes. Notably, DEPe treatment increased the secretion of the M1 marker IL-8 and the M2 marker IL-10 in both MΦ subtypes, whereas it reduced lipopolysaccharide-induced IL-6 and IL-12p40 secretion in M1 MΦ. In M2 MΦ, DEPe exposure led to a reduction of CD200R expression and of CCL17, CCL18 and CCL22 secretion, associated with a lower chemotaxis of CCR4-positive cells. DEPe activated the Nrf2 and AhR pathways and induced expression of their reference target genes such as Hmox-1 and cytochrome P-4501B1 in M1 and M2 MΦ. Nrf2 or AhR silencing through RNA interference prevented DEPe-related down-regulation of IL-6. AhR silencing also inhibited the down-secretion of IL-12p40 and CCL18 in M1- and M2-DEPe-exposed MΦ, respectively. DEPs are therefore likely to alter expression of some M1 and M2 markers in an AhR- and Nrf2-dependent manner; such regulations may contribute to deleterious immune effects of atmospheric DEP. PMID:25710172

  7. Hypoxia Potentiates Palmitate-induced Pro-inflammatory Activation of Primary Human Macrophages.

    PubMed

    Snodgrass, Ryan G; Boß, Marcel; Zezina, Ekaterina; Weigert, Andreas; Dehne, Nathalie; Fleming, Ingrid; Brüne, Bernhard; Namgaladze, Dmitry

    2016-01-01

    Pro-inflammatory cytokines secreted by adipose tissue macrophages (ATMs) contribute to chronic low-grade inflammation and obesity-induced insulin resistance. Recent studies have shown that adipose tissue hypoxia promotes an inflammatory phenotype in ATMs. However, our understanding of how hypoxia modulates the response of ATMs to free fatty acids within obese adipose tissue is limited. We examined the effects of hypoxia (1% O2) on the pro-inflammatory responses of human monocyte-derived macrophages to the saturated fatty acid palmitate. Compared with normoxia, hypoxia significantly increased palmitate-induced mRNA expression and protein secretion of IL-6 and IL-1β. Although palmitate-induced endoplasmic reticulum stress and nuclear factor κB pathway activation were not enhanced by hypoxia, hypoxia increased the activation of JNK and p38 mitogen-activated protein kinase signaling in palmitate-treated cells. Inhibition of JNK blocked the hypoxic induction of pro-inflammatory cytokine expression, whereas knockdown of hypoxia-induced transcription factors HIF-1α and HIF-2α alone or in combination failed to reduce IL-6 and only modestly reduced IL-1β gene expression in palmitate-treated hypoxic macrophages. Enhanced pro-inflammatory cytokine production and JNK activity under hypoxia were prevented by inhibiting reactive oxygen species generation. In addition, silencing of dual-specificity phosphatase 16 increased normoxic levels of IL-6 and IL-1β and reduced the hypoxic potentiation in palmitate-treated macrophages. The secretome of hypoxic palmitate-treated macrophages promoted IL-6 and macrophage chemoattractant protein 1 expression in primary human adipocytes, which was sensitive to macrophage JNK inhibition. Our results reveal that the coexistence of hypoxia along with free fatty acids exacerbates macrophage-mediated inflammation. PMID:26578520

  8. E-NTPDase (ecto-nucleoside triphosphate diphosphohydrolase) of Leishmania amazonensis inhibits macrophage activation.

    PubMed

    Gomes, Rodrigo Saar; de Carvalho, Luana Cristina Faria; de Souza Vasconcellos, Raphael; Fietto, Juliana Lopes Rangel; Afonso, Luís Carlos Crocco

    2015-04-01

    Leishmania amazonensis, the causal agent of diffuse cutaneous leishmaniasis, is known for its ability to modulate the host immune response. Because a relationship between ectonucleotidase activity and the ability of Leishmania to generate injury in C57BL/6 mice has been demonstrated, in this study we evaluated the involvement of ecto-nucleoside triphosphate diphosphohydrolase (E-NTPDase) activity of L. amazonensis in the process of infection of J774-macrophages. Our results show that high-activity parasites show increased survival rate in LPS/IFN-γ-activated cells, by inhibiting the host-cell NO production. Conversely, inhibition of E-NTPDase activity reduces the parasite survival rates, an effect associated with increased macrophage NO production. E-NTPDase activity generates substrate for the production of extracellular adenosine, which binds to A2B receptors and reduces IL-12 and TNF-α produced by activated macrophages, thus inhibiting NO production. These results indicate that E-NTPDase activity is important for survival of L. amazonensis within macrophages, showing the role of the enzyme in modulating macrophage response and lower NO production, which ultimately favors infection. Our results point to a new mechanism of L. amazonensis infection that may pave the way for the development of new treatments for this neglected disease. PMID:25554487

  9. Progranulin promotes activation of microglia/macrophage after pilocarpine-induced status epilepticus.

    PubMed

    Zhu, Shanshan; Tai, Chao; Petkau, Terri L; Zhang, Si; Liao, Chengyong; Dong, Zhifang; Wen, Wendy; Chang, Qing; Tian Wang, Yu; MacVicar, Brian A; Leavitt, Blair R; Jia, William; Cynader, Max S

    2013-09-12

    Progranulin (PGRN) haploinsufficiency accounts for up to 10% of frontotemporal lobe dementia. PGRN has also been implicated in neuroinflammation in acute and chronic neurological disorders. Here we report that both protein and mRNA levels of cortical and hippocampal PGRN are significantly enhanced following pilocarpine-induced status epilepticus. We also identify intense PGRN immunoreactivity that colocalizes with CD11b in seizure-induced animals, suggesting that PGRN elevation occurs primarily in activated microglia and macrophages. To test the role of PGRN in activation of microglia/macrophages, we apply recombinant PGRN protein directly into the hippocampal formation, and observe no change in the number of CD11b(+) microglia/macrophages in the dentate gyrus. However, with pilocarpine-induced status epilepticus, PGRN application significantly increases the number of CD11b(+) microglia/macrophages in the dentate gyrus, without affecting the extent of hilar cell death. In addition, the number of CD11b(+) microglia/macrophages induced by status epilepticus is not significantly different between PGRN knockout mice and wildtype. Our findings suggest that status epilepticus induces PGRN expression, and that PGRN potentiates but is not required for seizure-induced microglia/macrophage activation.

  10. Activation of TNFR2 sensitizes macrophages for TNFR1-mediated necroptosis

    PubMed Central

    Siegmund, Daniela; Kums, Juliane; Ehrenschwender, Martin; Wajant, Harald

    2016-01-01

    Macrophages express TNFR1 as well as TNFR2 and are also major producers of tumor necrosis factor (TNF), especially upon contact with pathogen-associated molecular patterns. Consequently, TNF not only acts as a macrophage-derived effector molecule but also regulates the activity and viability of macrophages. Here, we investigated the individual contribution of TNFR1 and TNFR2 to TNF-induced cell death in macrophages. Exclusive stimulation of TNFR1 showed no cytotoxic effect whereas selective stimulation of TNFR2 displayed mild cytotoxicity. Intriguingly, the latter was strongly enhanced by the caspase inhibitor zVAD-fmk. The strong cytotoxic activity of TNFR2 in the presence of zVAD-fmk was reversed by necrostatin-1, indicating necroptotic cell death. TNFR1- and TNF-deficient macrophages turned out to be resistant against TNFR2-induced cell death. In addition, the cIAP-depleting SMAC mimetic BV6 also enforced TNF/TNFR1-mediated necroptotic cell death in the presence of zVAD-fmk. In sum, our data suggest a model in which TNFR2 sensitizes macrophages for endogenous TNF-induced TNFR1-mediated necroptosis by the known ability of TNFR2 to interfere with the survival activity of TRAF2-cIAP1/2 complexes.

  11. Importance of Endosomal Cathelicidin Degradation To Enhance DNA-Induced Chicken Macrophage Activation.

    PubMed

    Coorens, Maarten; van Dijk, Albert; Bikker, Floris; Veldhuizen, Edwin J A; Haagsman, Henk P

    2015-10-15

    Cathelicidins are essential in the protection against invading pathogens through both their direct antimicrobial activity and their immunomodulatory functions. Although cathelicidins are known to modulate activation by several TLR ligands, little is known about their influence on DNA-induced macrophage activation. In this study, we explored the effects of cathelicidins on DNA-induced activation of chicken macrophages and elucidated the intracellular processes underlying these effects. Our results show that chicken cathelicidin (CATH)-2 strongly enhances DNA-induced activation of both chicken and mammalian macrophages because of enhanced endocytosis of DNA-CATH-2 complexes. After endocytosis, DNA is liberated from the complex because of proteolytic breakdown of CATH-2, after which TLR21 is activated. This leads to increased cytokine expression and NO production. Through the interaction with DNA, CATH-2 can play an important role in modulating the immune response at sites of infection. These observations underline the importance of cathelicidins in sensing bacterial products and regulating immune responses.

  12. Development of ostrich thrombocytes and monocyte-derived macrophages in culture and the control of Toxoplasma gondii reproduction after macrophage activation.

    PubMed

    Miranda, Farlen J B; Damasceno-Sá, João Cláudio; DaMatta, Renato A

    2016-01-01

    Raising ostriches became an important economic activity after their products became commodities. The health of farm animals is of paramount importance, so assessing basic immunological responses is necessary to better understand health problems. We developed a method to obtain ostrich thrombocytes and macrophages. The thrombocytes died by apoptosis after 48 h in culture, and the macrophages expanded in size and increased the number of acidic compartments. Macrophages were activated by chicken interferon-γ, producing high levels of nitric oxide. Toxoplasma gondii was able to infect these macrophages, and activation controlled parasitic reproduction. T. gondii, however, persisted in these cells, and infection reduced the production of nitric oxide. These results are important for the future assessment of the basic cellular and immunobiology of ostriches and demonstrate T. gondii suppression of nitric oxide production. PMID:26794839

  13. Microglial M1/M2 polarization and metabolic states.

    PubMed

    Orihuela, Ruben; McPherson, Christopher A; Harry, Gaylia Jean

    2016-02-01

    Microglia are critical nervous system-specific immune cells serving as tissue-resident macrophages influencing brain development, maintenance of the neural environment, response to injury and repair. As influenced by their environment, microglia assume a diversity of phenotypes and retain the capability to shift functions to maintain tissue homeostasis. In comparison with peripheral macrophages, microglia demonstrate similar and unique features with regards to phenotype polarization, allowing for innate immunological functions. Microglia can be stimulated by LPS or IFN-γ to an M1 phenotype for expression of pro-inflammatory cytokines or by IL-4/IL-13 to an M2 phenotype for resolution of inflammation and tissue repair. Increasing evidence suggests a role of metabolic reprogramming in the regulation of the innate inflammatory response. Studies using peripheral immune cells demonstrate that polarization to an M1 phenotype is often accompanied by a shift in cells from oxidative phosphorylation to aerobic glycolysis for energy production. More recently, the link between polarization and mitochondrial energy metabolism has been considered in microglia. Under these conditions, energy demands would be associated with functional activities and cell survival and thus, may serve to influence the contribution of microglia activation to various neurodegenerative conditions. This review examines the polarization states of microglia and their relationship to mitochondrial metabolism. Additional supporting experimental data are provided to demonstrate mitochondrial metabolic shifts in primary microglia and the BV-2 microglia cell line induced under LPS (M1) and IL-4/IL-13 (M2) polarization.

  14. Differential effects of osteopontin on the cytotoxic activity of macrophages from young and old mice.

    PubMed Central

    Rollo, E E; Denhardt, D T

    1996-01-01

    Osteopontin (OPN) is a secreted phosphoprotein found in body fluids (e.g. plasma, urine, milk) and in mineralized tissues. Its expression is increased in many transformed cells and in normal cells exposed to various cytokines. When stimulated with the inflammatory mediators lipopolysaccharide and interferon-gamma, mouse macrophages secrete nitric oxide (NO) as a cytotoxic agent effective against microbial invaders and tumour cells. This report documents (1) that thioglycollate-elicited peritoneal macrophages, activated with the inflammatory mediators, produced less NO and exhibited reduced cytotoxicity towards target cells when they were obtained from old animals than when they were obtained from young animals; and (2) that OPN was able to inhibit both the induced NO synthesis and cytotoxicity, but more effectively in macrophages from the young animals than those from the old animals. This may be due to the observed higher level of OPN expression in macrophages from old animals. Images Figure 1 Figure 2 PMID:8881770

  15. Coculture with intraocular lens material-activated macrophages induces an inflammatory phenotype in lens epithelial cells.

    PubMed

    Pintwala, Robert; Postnikoff, Cameron; Molladavoodi, Sara; Gorbet, Maud

    2015-03-01

    Cataracts are the leading cause of blindness worldwide, requiring surgical implantation of an intraocular lens. Despite evidence of leukocyte ingress into the postoperative lens, few studies have investigated the leukocyte response to intraocular lens materials. A novel coculture model was developed to examine macrophage activation by hydrophilic acrylic (poly(2-hydroxyethyl methacrylate)) and hydrophobic acrylic (polymethylmethacrylate) commercial intraocular lens. The human monocytic cell line THP-1 was differentiated into macrophages and cocultured with human lens epithelial cell line (HLE-B3) with or without an intraocular lens for one, two, four, or six days. Using flow cytometry and confocal microscopy, expression of the macrophage activation marker CD54 (intercellular adhesion molecule-1) and production of reactive oxygen species via the fluorogenic probe 2',7'-dichlorodihydrofluorescein diacetate were examined in macrophages. α-Smooth muscle actin, a transdifferentiation marker, was characterized in lens epithelial cells. The poly(2-hydroxyethyl methacrylate) intraocular lens prevented adhesion but induced significant macrophage activation (p < 0.03) versus control (no intraocular lens), while the polymethylmethacrylate intraocular lens enabled adhesion and multinucleated fusion, but induced no significant activation. Coculture with either intraocular lens increased reactive oxygen species production in macrophages after one day (p < 0.03) and increased expression of α-smooth muscle actin in HLE B-3 after six days, although only poly(2-hydroxyethyl methacrylate) induced a significant difference versus control (p < 0.01). Our results imply that-contrary to prior uveal biocompatibility understanding-macrophage adherence is not necessary for a strong inflammatory response to an intraocular lens, with hydrophilic surfaces inducing higher activation than hydrophobic surfaces. These findings provide a new method of inquiry into uveal

  16. Coculture with intraocular lens material-activated macrophages induces an inflammatory phenotype in lens epithelial cells.

    PubMed

    Pintwala, Robert; Postnikoff, Cameron; Molladavoodi, Sara; Gorbet, Maud

    2015-03-01

    Cataracts are the leading cause of blindness worldwide, requiring surgical implantation of an intraocular lens. Despite evidence of leukocyte ingress into the postoperative lens, few studies have investigated the leukocyte response to intraocular lens materials. A novel coculture model was developed to examine macrophage activation by hydrophilic acrylic (poly(2-hydroxyethyl methacrylate)) and hydrophobic acrylic (polymethylmethacrylate) commercial intraocular lens. The human monocytic cell line THP-1 was differentiated into macrophages and cocultured with human lens epithelial cell line (HLE-B3) with or without an intraocular lens for one, two, four, or six days. Using flow cytometry and confocal microscopy, expression of the macrophage activation marker CD54 (intercellular adhesion molecule-1) and production of reactive oxygen species via the fluorogenic probe 2',7'-dichlorodihydrofluorescein diacetate were examined in macrophages. α-Smooth muscle actin, a transdifferentiation marker, was characterized in lens epithelial cells. The poly(2-hydroxyethyl methacrylate) intraocular lens prevented adhesion but induced significant macrophage activation (p < 0.03) versus control (no intraocular lens), while the polymethylmethacrylate intraocular lens enabled adhesion and multinucleated fusion, but induced no significant activation. Coculture with either intraocular lens increased reactive oxygen species production in macrophages after one day (p < 0.03) and increased expression of α-smooth muscle actin in HLE B-3 after six days, although only poly(2-hydroxyethyl methacrylate) induced a significant difference versus control (p < 0.01). Our results imply that-contrary to prior uveal biocompatibility understanding-macrophage adherence is not necessary for a strong inflammatory response to an intraocular lens, with hydrophilic surfaces inducing higher activation than hydrophobic surfaces. These findings provide a new method of inquiry into uveal

  17. Inhibition of nuclear factor-kappa B activation decreases survival of Mycobacterium tuberculosis in human macrophages.

    PubMed

    Bai, Xiyuan; Feldman, Nicole E; Chmura, Kathryn; Ovrutsky, Alida R; Su, Wen-Lin; Griffin, Laura; Pyeon, Dohun; McGibney, Mischa T; Strand, Matthew J; Numata, Mari; Murakami, Seiji; Gaido, Loretta; Honda, Jennifer R; Kinney, William H; Oberley-Deegan, Rebecca E; Voelker, Dennis R; Ordway, Diane J; Chan, Edward D

    2013-01-01

    Nuclear factor-kappa B (NFκB) is a ubiquitous transcription factor that mediates pro-inflammatory responses required for host control of many microbial pathogens; on the other hand, NFκB has been implicated in the pathogenesis of other inflammatory and infectious diseases. Mice with genetic disruption of the p50 subunit of NFκB are more likely to succumb to Mycobacterium tuberculosis (MTB). However, the role of NFκB in host defense in humans is not fully understood. We sought to examine the role of NFκB activation in the immune response of human macrophages to MTB. Targeted pharmacologic inhibition of NFκB activation using BAY 11-7082 (BAY, an inhibitor of IκBα kinase) or an adenovirus construct with a dominant-negative IκBα significantly decreased the number of viable intracellular mycobacteria recovered from THP-1 macrophages four and eight days after infection. The results with BAY were confirmed in primary human monocyte-derived macrophages and alveolar macrophages. NFκB inhibition was associated with increased macrophage apoptosis and autophagy, which are well-established killing mechanisms of intracellular MTB. Inhibition of the executioner protease caspase-3 or of the autophagic pathway significantly abrogated the effects of BAY. We conclude that NFκB inhibition decreases viability of intracellular MTB in human macrophages via induction of apoptosis and autophagy.

  18. Inhibition of nuclear factor-kappa B activation decreases survival of Mycobacterium tuberculosis in human macrophages.

    PubMed

    Bai, Xiyuan; Feldman, Nicole E; Chmura, Kathryn; Ovrutsky, Alida R; Su, Wen-Lin; Griffin, Laura; Pyeon, Dohun; McGibney, Mischa T; Strand, Matthew J; Numata, Mari; Murakami, Seiji; Gaido, Loretta; Honda, Jennifer R; Kinney, William H; Oberley-Deegan, Rebecca E; Voelker, Dennis R; Ordway, Diane J; Chan, Edward D

    2013-01-01

    Nuclear factor-kappa B (NFκB) is a ubiquitous transcription factor that mediates pro-inflammatory responses required for host control of many microbial pathogens; on the other hand, NFκB has been implicated in the pathogenesis of other inflammatory and infectious diseases. Mice with genetic disruption of the p50 subunit of NFκB are more likely to succumb to Mycobacterium tuberculosis (MTB). However, the role of NFκB in host defense in humans is not fully understood. We sought to examine the role of NFκB activation in the immune response of human macrophages to MTB. Targeted pharmacologic inhibition of NFκB activation using BAY 11-7082 (BAY, an inhibitor of IκBα kinase) or an adenovirus construct with a dominant-negative IκBα significantly decreased the number of viable intracellular mycobacteria recovered from THP-1 macrophages four and eight days after infection. The results with BAY were confirmed in primary human monocyte-derived macrophages and alveolar macrophages. NFκB inhibition was associated with increased macrophage apoptosis and autophagy, which are well-established killing mechanisms of intracellular MTB. Inhibition of the executioner protease caspase-3 or of the autophagic pathway significantly abrogated the effects of BAY. We conclude that NFκB inhibition decreases viability of intracellular MTB in human macrophages via induction of apoptosis and autophagy. PMID:23634218

  19. Inhibition of Nuclear Factor-Kappa B Activation Decreases Survival of Mycobacterium tuberculosis in Human Macrophages

    PubMed Central

    Chmura, Kathryn; Ovrutsky, Alida R.; Su, Wen-Lin; Griffin, Laura; Pyeon, Dohun; McGibney, Mischa T.; Strand, Matthew J.; Numata, Mari; Murakami, Seiji; Gaido, Loretta; Honda, Jennifer R.; Kinney, William H.; Oberley-Deegan, Rebecca E.; Voelker, Dennis R.; Ordway, Diane J.; Chan, Edward D.

    2013-01-01

    Nuclear factor-kappa B (NFκB) is a ubiquitous transcription factor that mediates pro-inflammatory responses required for host control of many microbial pathogens; on the other hand, NFκB has been implicated in the pathogenesis of other inflammatory and infectious diseases. Mice with genetic disruption of the p50 subunit of NFκB are more likely to succumb to Mycobacterium tuberculosis (MTB). However, the role of NFκB in host defense in humans is not fully understood. We sought to examine the role of NFκB activation in the immune response of human macrophages to MTB. Targeted pharmacologic inhibition of NFκB activation using BAY 11-7082 (BAY, an inhibitor of IκBα kinase) or an adenovirus construct with a dominant-negative IκBα significantly decreased the number of viable intracellular mycobacteria recovered from THP-1 macrophages four and eight days after infection. The results with BAY were confirmed in primary human monocyte-derived macrophages and alveolar macrophages. NFκB inhibition was associated with increased macrophage apoptosis and autophagy, which are well-established killing mechanisms of intracellular MTB. Inhibition of the executioner protease caspase-3 or of the autophagic pathway significantly abrogated the effects of BAY. We conclude that NFκB inhibition decreases viability of intracellular MTB in human macrophages via induction of apoptosis and autophagy. PMID:23634218

  20. 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

    2010-06-01

    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.

  1. Slamf8 is a negative regulator of Nox2 activity in macrophages

    PubMed Central

    Wang, Guoxing; Abadía-Molina, Ana C; Berger, Scott B; Romero, Xavier; O'Keeffe, Michael; Rojas-Barros, Domingo I.; Aleman, Marta; Liao, Gongxian; Maganto-García, Elena; Fresno, Manuel; Wang, Ninghai; Detre, Cynthia; Terhorst, Cox

    2012-01-01

    Slamf8 (CD353) is a cell surface receptor that is expressed upon activation of macrophages by interferon-gamma or bacteria. Here we report that a very high Nox2 activity enzyme was found in Slamf8−/− macrophages in response to E.coli or S.aureus, but also to phorbol myristate acetate. The elevated Nox2 activity in Slamf8−/− macrophages was also demonstrated in E.coli or S.aureus phagosomes by using a pH indicator system, and was further confirmed by a reduction of the enzyme activity after transfection of the receptor into Slamf8-deficient primary macrophages or RAW 264.7 cells. Upon exposure to bacteria and/or phorbol myristate acetate, PKC activity in Slamf8−/− macrophages is increased. This results in an enhanced phosphorylation of p40phox, one key component of the Nox2 enzyme complex, which in turn leads to greater Nox2 activity. Taken together, the data show that upon response to inflammation-associated stimuli the inducible receptor Slamf8 negatively regulates inflammatory responses. PMID:22593622

  2. L-arginine-dependent reactive nitrogen intermediates as mediators of tumor cell killing by activated macrophages.

    PubMed

    Keller, R; Geiges, M; Keist, R

    1990-03-01

    The capacities of lymphokines and of various microbes to induce in a pure population of bone marrow-derived mononuclear phagocytes tumoricidal activity and/or the production of L-arginine-dependent reactive nitrogen intermediates, measured by the release of nitrite, were comparatively assessed. These parameters were found to be closely correlated in a variety of experimental situations, i.e., enhanced by a surplus of L-arginine and abrogated by N-monomethyl-L-arginine, a selective inhibitor of L-arginine-dependent effector mechanisms. In other macrophage/tumor cell combinations, such correlation was less obvious or not at all detectable, suggesting that, in these models, L-arginine-dependent reactive nitrogen intermediates are not or not alone responsible for the mediation of tumoricidal activity by activated macrophages. Collectively, the present findings suggest that the mechanism of tumor cell killing by activated macrophages may differ, depending on the tumor cell type and the pathway of macrophage activation. Among the various effector mechanisms considered to be involved in tumor cell killing by activated macrophages, L-arginine-dependent reactive nitrogen intermediates appear to hold a major role.

  3. IFN-γ Prevents Adenosine Receptor (A2bR) Upregulation To Sustain the Macrophage Activation Response.

    PubMed

    Cohen, Heather B; Ward, Amanda; Hamidzadeh, Kajal; Ravid, Katya; Mosser, David M

    2015-10-15

    The priming of macrophages with IFN-γ prior to TLR stimulation results in enhanced and prolonged inflammatory cytokine production. In this study, we demonstrate that, following TLR stimulation, macrophages upregulate the adenosine 2b receptor (A2bR) to enhance their sensitivity to immunosuppressive extracellular adenosine. This upregulation of A2bR leads to the induction of macrophages with an immunoregulatory phenotype and the downregulation of inflammation. IFN-γ priming of macrophages selectively prevents the induction of the A2bR in macrophages to mitigate sensitivity to adenosine and to prevent this regulatory transition. IFN-γ-mediated A2bR blockade leads to a prolonged production of TNF-α and IL-12 in response to TLR ligation. The pharmacologic inhibition or the genetic deletion of the A2bR results in a hyperinflammatory response to TLR ligation, similar to IFN-γ treatment of macrophages. Conversely, the overexpression of A2bR on macrophages blunts the IFN-γ effects and promotes the development of immunoregulatory macrophages. Thus, we propose a novel mechanism whereby IFN-γ contributes to host defense by desensitizing macrophages to the immunoregulatory effects of adenosine. This mechanism overcomes the transient nature of TLR activation, and prolongs the antimicrobial state of the classically activated macrophage. This study may offer promising new targets to improve the clinical outcome of inflammatory diseases in which macrophage activation is dysregulated. PMID:26355158

  4. Macrophages and inflammatory mediators in chemical toxicity: a battle of forces.

    PubMed

    Laskin, Debra L

    2009-08-01

    Macrophages function as control switches of the immune system, providing a balance between pro- and anti-inflammatory responses. To accomplish this, they develop into different subsets: classically (M1) or alternatively (M2) activated macrophages. Whereas M1 macrophages display a cytotoxic, proinflammatory phenotype, much like the soldiers of The Dark Side of The Force in the Star Wars movies, M2 macrophages, like Jedi fighters, suppress immune and inflammatory responses and participate in wound repair and angiogenesis. Critical to the actions of these divergent or polarized macrophage subpopulations is the regulated release of inflammatory mediators. When properly controlled, M1 macrophages effectively destroy invading pathogens, tumor cells, and foreign materials. However, when M1 activation becomes excessive or uncontrolled, these cells can succumb to The Dark Side, releasing copious amounts of cytotoxic mediators that contribute to disease pathogenesis. The activity of M1 macrophages is countered by The Force of alternatively activated M2 macrophages, which release anti-inflammatory cytokines, growth factors, and mediators involved in extracellular matrix turnover and tissue repair. It is the balance in the production of mediators by these two macrophage subpopulations that ultimately determines the outcome of the tissue response to chemical toxicants.

  5. Localization and activity of various lysosomal proteases in Leishmania amazonensis-infected macrophages.

    PubMed Central

    Prina, E; Antoine, J C; Wiederanders, B; Kirschke, H

    1990-01-01

    In mammalian hosts, Leishmania amastigotes are obligatory intracellular parasites of macrophages and multiply within parasitophorous vacuoles of phagolysosomal origin. To understand how they escape the harmful strategies developed by macrophages to kill ingested microorganisms, it is important to obtain information on the functional state of parasitophorous vacuole. For this purpose, we studied the intracellular distribution and activity of host lysosomal proteases in rat bone marrow-derived macrophages infected with Leishmania amazonensis amastigotes. Localization of cathepsins B, H, L, and D was investigated by using specific immunoglobulins. In uninfected macrophages, these enzymes were located in perinuclear granules (most of them were probably secondary lysosomes) which, after infection, disappeared progressively. In infected macrophages, cathepsins were detected mainly in the parasitophorous vacuoles, suggesting that the missing secondary lysosomes had fused with these organelles. Biochemical assays of various proteases (cathepsins B, H, and D and dipeptidyl peptidases I and II) showed that infection was accompanied by a progressive increase of all activities tested, except that of dipeptidyl peptidase II, which remained constant. No more than 1 to 10% of these activities could be attributed to amastigotes. These data indicate that (i) Leishmania infection is followed by an increased synthesis and/or a reduced catabolism of host lysosomal proteases, and (ii) amastigotes grow in a compartment rich in apparently fully active proteases. Unexpectedly, it was found that infected and uninfected macrophages degraded endocytosed proteins similarly. The lack of correlation in infected macrophages between increase of protease activities and catabolism of exogenous proteins could be linked to the huge increase in volume of the lysosomal compartment. Images PMID:2187806

  6. Alternatively activated macrophages determine repair of the infarcted adult murine heart

    PubMed Central

    Shiraishi, Manabu; Shintani, Yasunori; Shintani, Yusuke; Ishida, Hidekazu; Saba, Rie; Yamaguchi, Atsushi; Adachi, Hideo; Yashiro, Kenta

    2016-01-01

    Alternatively activated (also known as M2) macrophages are involved in the repair of various types of organs. However, the contribution of M2 macrophages to cardiac repair after myocardial infarction (MI) remains to be fully characterized. Here, we identified CD206+F4/80+CD11b+ M2-like macrophages in the murine heart and demonstrated that this cell population predominantly increases in the infarct area and exhibits strengthened reparative abilities after MI. We evaluated mice lacking the kinase TRIB1 (Trib1–/–), which exhibit a selective depletion of M2 macrophages after MI. Compared with control animals, Trib1–/– mice had a catastrophic prognosis, with frequent cardiac rupture, as the result of markedly reduced collagen fibril formation in the infarct area due to impaired fibroblast activation. The decreased tissue repair observed in Trib1–/– mice was entirely rescued by an external supply of M2-like macrophages. Furthermore, IL-1α and osteopontin were suggested to be mediators of M2-like macrophage–induced fibroblast activation. In addition, IL-4 administration achieved a targeted increase in the number of M2-like macrophages and enhanced the post-MI prognosis of WT mice, corresponding with amplified fibroblast activation and formation of more supportive fibrous tissues in the infarcts. Together, these data demonstrate that M2-like macrophages critically determine the repair of infarcted adult murine heart by regulating fibroblast activation and suggest that IL-4 is a potential biological drug for treating MI. PMID:27140396

  7. Effect of age on proteasomal activity of T cells and macrophages

    Technology Transfer Automated Retrieval System (TEKTRAN)

    T cell function is impaired with aging. Proteasome activity in T cells is important for T cell activation and its activity in macrophages is required for processing antigens in order to be presented via class I major histocompatibility complex to CD8+ T cells. Since studies have demonstrated that pr...

  8. Dihydro-CDDO-trifluoroethyl amide suppresses inflammatory responses in macrophages via activation of Nrf2

    SciTech Connect

    Li, Bin; Abdalrahman, Akram; Lai, Yimu; Janicki, Joseph S.; Ward, Keith W.; Meyer, Colin J.; Wang, Xing Li; Tang, Dongqi; Cui, Taixing

    2014-02-21

    Highlights: • Dh404 suppresses the expression of a selected set of pro-inflammatory cytokines in inflamed macrophages via activating Nrf2. • Dh404 activates Nrf2 while keeping Keap1 function intact in macrophages. • Dh404 minimally regulates NF-κB pathway in macrophages. - Abstract: Nuclear factor erythroid 2-related factor (Nrf2) is the major regulator of cellular defenses against various pathological stresses in a variety of organ systems, thus Nrf2 has evolved to be an attractive drug target for the treatment and/or prevention of human disease. Several synthetic oleanolic triterpenoids including dihydro-CDDO-trifluoroethyl amide (dh404) appear to be potent activators of Nrf2 and exhibit chemopreventive promises in multiple disease models. While the pharmacological efficacy of Nrf2 activators may be dependent on the nature of Nrf2 activation in specific cell types of target organs, the precise role of Nrf2 in mediating biological effects of Nrf2 activating compounds in various cell types remains to be further explored. Herein we report a unique and Nrf2-dependent anti-inflammatory profile of dh404 in inflamed macrophages. In lipopolysaccharide (LPS)-inflamed RAW264.7 macrophages, dh404 dramatically suppressed the expression of pro-inflammatory cytokines including inducible nitric oxide synthase (iNOS), monocyte chemotactic protein-1 (MCP-1), and macrophage inflammatory protein-1 beta (MIP-1β), while minimally regulating the expression of interleulin-6 (IL-6), IL-1β, and tumor necrosis factor alpha (TNFα). Dh404 potently activated Nrf2 signaling; however, it did not affect LPS-induced NF-κB activity. Dh404 did not interrupt the interaction of Nrf2 with its endogenous inhibitor Kelch-like ECH associating protein 1 (Keap1) in macrophages. Moreover, knockout of Nrf2 blocked the dh404-induced anti-inflammatory responses in LPS-inflamed macrophages. These results demonstrated that dh404 suppresses pro-inflammatory responses in macrophages via an activation

  9. Tumour necrosis factor (TNF) as a mediator of macrophage helminthotoxic activity.

    PubMed

    James, S L; Glaven, J; Goldenberg, S; Meltzer, M S; Pearce, E

    1990-01-01

    Lymphokine-activated macrophages are cytotoxic for larvae of the helminth parasite Schistosoma mansoni. That soluble secreted factors may mediate this cytotoxicity was suggested by the observation that culture supernatant fluids from stimulated macrophages also exhibited larvacidal activity. These fluids contain the monokine tumour necrosis factor (TNF). Several observations indicated that TNF is directly toxic to schistosome larvae. Cytotoxic sera taken from BCG- or S. mansoni-immunized mice after endotoxin challenge killed schistosomula in vitro, and upon gel filtration the larvacidal factor(s) in the sera co-eluted with the tumoricidal activity defined as TNF. Recombinant-derived TNF exhibited direct toxicity to schistosomula at high concentrations, or at lower concentrations in the presence of IFN gamma. The larvacidal activity of macrophage supernatant fluids was abrogated by addition of either anti-TNF antisera or Zn+2, which has been shown to inhibit TNF-induced damage of tumour cells. Anti-TNF and Zn+2 likewise suppressed schistosomulum killing by lymphokine-activated peritoneal macrophages or the IC-21 macrophage line, indicating that TNF also plays a role in the effector mechanism of larval killing by whole cells. PMID:2314921

  10. 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.

  11. Polyphenols from Chilean Propolis and Pinocembrin Reduce MMP-9 Gene Expression and Activity in Activated Macrophages

    PubMed Central

    Saavedra, Nicolás; Cuevas, Alejandro; Cavalcante, Marcela F.; Dörr, Felipe A.; Saavedra, Kathleen; Zambrano, Tomás; Abdalla, Dulcineia S. P.; Salazar, Luis A.

    2016-01-01

    Polyphenols from diverse sources have shown anti-inflammatory activity. In the context of atherosclerosis, macrophages play important roles including matrix metalloproteinases synthesis involved in degradation of matrix extracellular components affecting the atherosclerotic plaque stability. We prepared a propolis extract and pinocembrin in ethanol solution. Propolis extract was chemically characterized using LC-MS. The effect of treatments on gene expression and proteolytic activity was measured in vitro using murine macrophages activated with LPS. Cellular toxicity associated with both treatments and the vehicle was determined using MTT and apoptosis/necrosis detection assays. MMP-9 gene expression and proteolytic activity were measured using qPCR and zymography, respectively. Thirty-two compounds were identified in the propolis extract, including pinocembrin among its major components. Treatment with either ethanolic extract of propolis or pinocembrin inhibits MMP-9 gene expression in a dose-dependent manner. Similarly, an inhibitory effect was observed in proteolytic activity. However, the effect showed by ethanolic extract of propolis was higher than the effect of pinocembrin, suggesting that MMP-9 inhibition results from a joint contribution between the components of the extract. These data suggest a potential role of polyphenols from Chilean propolis in the control of extracellular matrix degradation in atherosclerotic plaques. PMID:27119082

  12. Immunocytochemical localization of latent transforming growth factor-beta1 activation by stimulated macrophages

    NASA Technical Reports Server (NTRS)

    Chong, H.; Vodovotz, Y.; Cox, G. W.; Barcellos-Hoff, M. H.; Chatterjee, A. (Principal Investigator)

    1999-01-01

    Transforming growth factor-beta1 (TGF-beta) is secreted in a latent form consisting of mature TGF-beta noncovalently associated with its amino-terminal propeptide, which is called latency associated peptide (LAP). Biological activity depends upon the release of TGF-beta from the latent complex following extracellular activation, which appears to be the key regulatory mechanism controlling TGF-beta action. We have identified two events associated with latent TGF-beta (LTGF-beta) activation in vivo: increased immunoreactivity of certain antibodies that specifically detect TGF-beta concomitant with decreased immunoreactivity of antibodies to LAP. Macrophages stimulated in vitro with interferon-gamma and lipopolysaccharide reportedly activate LTGF-beta via cell membrane-bound protease activity. We show through dual immunostaining of paraformaldehyde-fixed macrophages that such physiological TGF-beta activation is accompanied by a loss of LAP immunoreactivity with concomitant revelation of TGF-beta epitopes. The induction of TGF-beta immunoreactivity colocalized with immunoreactive betaglycan/RIII in activated macrophages, suggesting that LTGF-beta activation occurs on the cell surface. Confocal microscopy of metabolically active macrophages incubated with antibodies to TGF-beta and betaglycan/RIII prior to fixation supported the localization of activation to the cell surface. The ability to specifically detect and localize LTGF-beta activation provides an important tool for studies of its regulation.

  13. LL37:DNA complexes provide antimicrobial activity against intracellular bacteria in human macrophages.

    PubMed

    Stephan, Alexander; Batinica, Marina; Steiger, Julia; Hartmann, Pia; Zaucke, Frank; Bloch, Wilhelm; Fabri, Mario

    2016-08-01

    As part of the innate host response neutrophils release neutrophil extracellular traps (NETs), protein:DNA complexes that contain a number of antimicrobial peptides (AMPs), such as cathelicidin. Human cathelicidin in its active form, LL37, has potent antimicrobial activity against bacteria. However, whether LL37 derived from NETs contributes to antimicrobial activity against intracellular pathogens remains unclear. Here, we report that NETs induced by mycobacteria contain cathelicidin. Human macrophages internalized NET-bound cathelicidin, which is transported to lysosomal compartments. Furthermore, using a model of in vitro-generated LL37:DNA complexes we found that LL37 derived from such complexes attacks mycobacteria in macrophage phagolysosomes resulting in antimicrobial activity. Taken together, our results suggest a mechanism by which LL37 in complex with DNA contributes to host defence against intracellular bacteria in human macrophages.

  14. Polyoxygenated Cholesterol Ester Hydroperoxide Activates TLR4 and SYK Dependent Signaling in Macrophages

    PubMed Central

    Choi, Soo-Ho; Yin, Huiyong; Ravandi, Amir; Armando, Aaron; Dumlao, Darren; Kim, Jungsu; Almazan, Felicidad; Taylor, Angela M.; McNamara, Coleen A.; Tsimikas, Sotirios; Dennis, Edward A.; Witztum, Joseph L.; Miller, Yury I.

    2013-01-01

    Oxidation of low-density lipoprotein (LDL) is one of the major causative mechanisms in the development of atherosclerosis. In previous studies, we showed that minimally oxidized LDL (mmLDL) induced inflammatory responses in macrophages, macropinocytosis and intracellular lipid accumulation and that oxidized cholesterol esters (OxCEs) were biologically active components of mmLDL. Here we identified a specific OxCE molecule responsible for the biological activity of mmLDL and characterized signaling pathways in macrophages in response to this OxCE. Using liquid chromatography – tandem mass spectrometry and biological assays, we identified an oxidized cholesteryl arachidonate with bicyclic endoperoxide and hydroperoxide groups (BEP-CE) as a specific OxCE that activates macrophages in a TLR4/MD-2-dependent manner. BEP-CE induced TLR4/MD-2 binding and TLR4 dimerization, phosphorylation of SYK, ERK1/2, JNK and c-Jun, cell spreading and uptake of dextran and native LDL by macrophages. The enhanced macropinocytosis resulted in intracellular lipid accumulation and macrophage foam cell formation. Bone marrow-derived macrophages isolated from TLR4 and SYK knockout mice did not respond to BEP-CE. The presence of BEP-CE was demonstrated in human plasma and in the human plaque material captured in distal protection devices during percutaneous intervention. Our results suggest that BEP-CE is an endogenous ligand that activates the TLR4/SYK signaling pathway. Because BEP-CE is present in human plasma and human atherosclerotic lesions, BEP-CE-induced and TLR4/SYK-mediated macrophage responses may contribute to chronic inflammation in human atherosclerosis. PMID:24376657

  15. Lactobacillus rhamnosus GG improves glucose tolerance through alleviating ER stress and suppressing macrophage activation in db/db mice

    PubMed Central

    Park, Kun-Young; Kim, Bobae; Hyun, Chang-Kee

    2015-01-01

    Although recent studies have reported that Lactobacillus rhamnosus GG (LGG), the most extensively studied probiotic strain, exerts an anti-hyperglycemic effect on several rodent models, the underlying mechanism remains unclear. In this study, twenty male C57BL/KsJ-db/db (db/db) mice were divided into 2 groups, LGG-treated and control group, which received a daily dose of LGG (1 × 108 CFU per mouse) and PBS orally for 4 weeks, respectively. We observed that glucose tolerance was significantly improved in LGG-treated db/db mice. Insulin-stimulated Akt phosphorylation and GLUT4 translocation were higher in skeletal muscle of LGG-treated mice relative to their controls. It was also observed that LGG treatment caused significant reductions in endoplasmic reticulum (ER) stress in skeletal muscle and M1-like macrophage activation in white adipose tissues. Our results indicate that the anti-diabetic effect of LGG in db/db mice is associated with alleviated ER stress and suppressed macrophage activation, resulting in enhanced insulin sensitivity. These findings suggest a therapeutic potential of probiotics for prevention and treatment of type 2 diabetes. PMID:26060355

  16. Expression of intercellular adhesion molecule-1 on macrophages in vitro as a marker of activation.

    PubMed

    Bernatchez, S F; Atkinson, M R; Parks, P J

    1997-10-01

    Macrophage activation is a major component of wound healing. It also determines the extent of inflammatory reactions and the response of the body to implanted materials. We have previously shown, using an in vitro model, that the extent of spreading of macrophages on different materials is a marker of activation, and that a soluble inducer has a dose-response effect on the secretion of cytokines in the culture medium. This work investigates the expression of three different cell surface markers [macrophages MAC-1, MAC-3 and intercellular adhesion molecule-1 (ICAM-1)] on macrophages in vitro using confocal microscopy and shows that ICAM-1 is also a marker of macrophage activation in this model. We observed increased amounts of ICAM-1 on activated macrophages compared to unactivated macrophages, whereas MAC-1 and MAC-3 were either expressed constitutively or demonstrated no quantitative change in expression after activation under the same experimental conditions. We also tested the expression of ICAM-1 with various concentrations of soluble inducers (lipopolysaccharide, 0.001, 0.01, 0.1, 1 and 10 micrograms ml-1. S-27609, 0.1, 0.25, 0.5, 1, 2 and 3 micrograms ml-1 and on a sheet of polylactic acid alone or in combination with soluble inducers. All doses of soluble inducers induced the expression of ICAM-1 on cells grown in glass chamber slides. The induction was not dose related but seemed to work rather in an on-off manner. There was no effect of material on ICAM-1 expression on the cell surface when no soluble inducer was added. This was similar to cytokine secretion, which was not induced by our material alone. When either lipopolysaccharide or S-27609 was used in combination with the material, there was an increase in the average measured intensity of ICAM-1. In this in vitro model, ICAM-1 staining as measured by confocal microscopy is a marker for macrophage activation. Our results suggest that the extent of macrophage activation as measured by ICAM-1 and by

  17. Binding and activation of major histocompatibility complex class II-deficient macrophages by staphylococcal exotoxins

    NASA Technical Reports Server (NTRS)

    Beharka, A. A.; Armstrong, J. W.; Iandolo, J. J.; Chapes, S. K.; Spooner, B. S. (Principal Investigator)

    1994-01-01

    Macrophages from C2D transgenic mice deficient in the expression of major histocompatibility complex (MHC) class II proteins were used to identify binding sites for superantigens distinct from the MHC class II molecule. Iodinated staphylococcal enterotoxins A and B (SEA and SEB) and exfoliative toxins A and B (ETA and ETB) bound to C2D macrophages in a concentration-dependent and competitive manner. All four toxins increased F-actin concentration within 30 s of their addition to C2D macrophages, indicating that signal transduction occurred in response to toxin in the absence of class II MHC. Furthermore, ETA, ETB, SEA, and, to a lesser extent, SEB induced C2D macrophages to produce interleukin 6. Several molecular species on C2D macrophages with molecular masses of 140, 97, 61, 52, 43, and 37 kDa bound SEA in immunoprecipitation experiments. These data indicate the presence of novel, functionally active toxin binding sites on murine macrophages distinct from MHC class II molecules.

  18. In vivo manipulation (depletion versus activation) of testicular macrophages: central and local effects.

    PubMed

    Gaytan, F; Bellido, C; Morales, C; García, M; van Rooijen, N; Aguilar, E

    1996-07-01

    Testicular macrophages are a relevant cell type for the regulation of Leydig cell steroidogenesis. The availability of liposome technology allows in vivo manipulation of macrophages in order to analyze their role in the regulation of the hypothalamic-pituitary-testicular axis. In this study, adult (70 days of age) and prepubertal (22 days of age) rats were injected intratesticularly with liposomes containing either dichloromethylene diphosphonate (C12MDP) to deplete testicular macrophages or muramyl tripeptide (MTP-PE) to activate them. Control rats were injected with the corresponding volumes of 0.9% NaCl. Animals were killed 10 days after treatment. Adult rats injected bilaterally or unilaterally with C12MDP liposomes showed increased serum LH and testosterone concentrations, as well as increased testosterone concentrations in the testicular interstitial fluid. In unilaterally injected rats, testosterone concentrations in the interstitial fluid were higher in the macrophage-containing testes than in the contralateral, macrophage-depleted testes. Adult rats treated bilaterally with MTP-PE liposomes showed increased numbers of testicular macrophages, whereas the number of Leydig cells was unchanged. Serum LH concentrations were decreased, but no changes were found in testosterone concentrations. Prepubertal rats treated bilaterally with C12MDP liposomes showed decreased numbers of Leydig cells. However, serum LH and testosterone concentrations were increased. Otherwise, prepubertal rats treated bilaterally with MTP-PE liposomes showed increased numbers of macrophages and Leydig cells, as well as increased serum testosterone concentrations. These data suggest that testicular macrophage-derived factors act at two different levels in the pituitary-testicular axis: first, at a central level by inhibiting LH secretion, and secondly, at a local level by stimulating Leydig cell steroidogenesis.

  19. Identification of Caspase-6 as a New Regulator of Alternatively Activated Macrophages.

    PubMed

    Yao, Yongfang; Shi, Qian; Chen, Bing; Wang, Qingsong; Li, Xinda; Li, Long; Huang, Yahong; Ji, Jianguo; Shen, Pingping

    2016-08-12

    Alternatively activated macrophages (AAMs) play essential roles in the promotion of tissue remodeling, vasculogenesis, and tumor progression; however, the detailed mechanisms underlying the activation of AAMs remain largely unknown. Here, by using quantitative proteomic analysis, we identified 62 proteins that were up-regulated in IL-4-induced macrophages. Among these, Caspase-6 was increased significantly. Caspase-6 is important in the apoptotic signaling pathway; however, its role in non-apoptosis is also reported. Here, we first examined the non-apoptotic role of Caspase-6 in the alternative activation of macrophages after administration of IL-4, 4T1 tumor conditional medium, or co-culture with 4T1 cells. Both treatments promoted alternative activation of RAW264.7 cells and primary macrophages, whereas disruption of caspase-6 expression and activity could markedly suppress the biomarker levels of AAMs. Overexpression of Caspase-6 could significantly promote the activation of AAMs. Importantly, we further present evidence that caspase-6 could regulate breast cancer cell invasion by modulating MMP-2 and MMP-9 expression in 4T1 tumor-associated macrophages, as ablation of protein levels or activity of caspase-6 suppressed tumor cell invasion in vitro In conclusion, the observed results markedly expanded our views of the dynamic changes in protein composition during alternative activation of macrophages, and they revealed a critical new role of caspase-6 in regulating this cellular biological process, which suggested that caspase-6 might be a key nod molecule to regulate immunological steady-state and be a therapeutic candidate for tumor immunotherapy. PMID:27325699

  20. Inhibition of ecto-ATPase activities impairs HIV-1 infection of macrophages.

    PubMed

    Schachter, Julieta; Delgado, Kelly Valcárcel; Barreto-de-Souza, Victor; Bou-Habib, Dumith Chequer; Persechini, Pedro Muanis; Meyer-Fernandes, José Roberto

    2015-05-01

    Nucleotides and nucleosides are secreted into extracellular media at different concentrations as a consequence of different physiologic and pathological conditions. Ecto-nucleotidases, enzymes present on the surface of most cells, hydrolyze these extracellular nucleotides and reduce the concentration of them, thus affecting the activation of different nucleotide and nucleoside receptors. Also, ecto-nucleotidases are present in a number of microorganisms and play important roles in host-pathogen interactions. Here, we characterized the ecto-ATPase activities present on the surface of HIV-1 particle and human macrophages as well. We found that the kinetic properties of HIV-1 and macrophage ecto-ATPases are similar, suggesting that the enzyme is the same. This ecto-ATPase activity was increased in macrophages infected in vitro with HIV-1. Using three different non-related ecto-ATPase inhibitors-POM-1, ARL67156 and BG0-we showed that the inhibition of these macrophage and viral ecto-ATPase activities impairs HIV-1 infection. In addition, we also found that elevated extracellular concentrations of ATP inhibit HIV-1 production by infected macrophages.

  1. Nitric oxide/cGMP/PKG signaling pathway activated by M1-type muscarinic acetylcholine receptor cascade inhibits Na+-activated K+ currents in Kenyon cells.

    PubMed

    Hasebe, Masaharu; Yoshino, Masami

    2016-06-01

    The interneurons of the mushroom body, known as Kenyon cells, are essential for the long-term memory of olfactory associative learning in some insects. Some studies have reported that nitric oxide (NO) is strongly related to this long-term memory in Kenyon cells. However, the target molecules and upstream and downstream NO signaling cascades are not completely understood. Here we analyzed the effect of the NO signaling cascade on Na(+)-activated K(+) (KNa) channel activity in Kenyon cells of crickets (Gryllus bimaculatus). We found that two different NO donors, S-nitrosoglutathione (GSNO) and S-nitroso-N-acetyl-dl-penicillamine (SNAP), strongly suppressed KNa channel currents. Additionally, this inhibitory effect of GSNO on KNa channel activity was diminished by 1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one (ODQ), an inhibitor of soluble guanylate cyclase (sGC), and KT5823, an inhibitor of protein kinase G (PKG). Next, we analyzed the role of ACh in the NO signaling cascade. ACh strongly suppressed KNa channel currents, similar to NO donors. Furthermore, this inhibitory effect of ACh was blocked by pirenzepine, an M1 muscarinic ACh receptor antagonist, but not by 1,1-dimethyl-4-diphenylacetoxypiperidinium iodide (4-DAMP) and mecamylamine, an M3 muscarinic ACh receptor antagonist and a nicotinic ACh receptor antagonist, respectively. The ACh-induced inhibition of KNa channel currents was also diminished by the PLC inhibitor U73122 and the calmodulin antagonist W-7. Finally, we found that ACh inhibition was blocked by the nitric oxide synthase (NOS) inhibitor N(G)-nitro-l-arginine methyl ester (l-NAME). These results suggested that the ACh signaling cascade promotes NO production by activating NOS and NO inhibits KNa channel currents via the sGC/cGMP/PKG signaling cascade in Kenyon cells. PMID:26984419

  2. Full Spectrum of LPS Activation in Alveolar Macrophages of Healthy Volunteers by Whole Transcriptomic Profiling

    PubMed Central

    Zhao, Yutong; Zhao, Jing; Donahoe, Michael P.; Barge, Suchitra; Horne, William T.; Kolls, Jay K.; McVerry, Bryan J.; Birukova, Anastasiya; Tighe, Robert M.; Foster, W. Michael; Hollingsworth, John; Ray, Anuradha; Mallampalli, Rama; Ray, Prabir; Lee, Janet S.

    2016-01-01

    Despite recent advances in understanding macrophage activation, little is known regarding how human alveolar macrophages in health calibrate its transcriptional response to canonical TLR4 activation. In this study, we examined the full spectrum of LPS activation and determined whether the transcriptomic profile of human alveolar macrophages is distinguished by a TIR-domain-containing adapter-inducing interferon-β (TRIF)-dominant type I interferon signature. Bronchoalveolar lavage macrophages were obtained from healthy volunteers, stimulated in the presence or absence of ultrapure LPS in vitro, and whole transcriptomic profiling was performed by RNA sequencing (RNA-Seq). LPS induced a robust type I interferon transcriptional response and Ingenuity Pathway Analysis predicted interferon regulatory factor (IRF)7 as the top upstream regulator of 89 known gene targets. Ubiquitin-specific peptidase (USP)-18, a negative regulator of interferon α/β responses, was among the top up-regulated genes in addition to IL10 and USP41, a novel gene with no known biological function but with high sequence homology to USP18. We determined whether IRF-7 and USP-18 can influence downstream macrophage effector cytokine production such as IL-10. We show that IRF-7 siRNA knockdown enhanced LPS-induced IL-10 production in human monocyte-derived macrophages, and USP-18 overexpression attenuated LPS-induced production of IL-10 in RAW264.7 cells. Quantitative PCR confirmed upregulation of USP18, USP41, IL10, and IRF7. An independent cohort confirmed LPS induction of USP41 and IL10 genes. These results suggest that IRF-7 and predicted downstream target USP18, both elements of a type I interferon gene signature identified by RNA-Seq, may serve to fine-tune early cytokine response by calibrating IL-10 production in human alveolar macrophages. PMID:27434537

  3. 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.

  4. Cathepsin L maturation and activity is impaired in macrophages harboring M. avium and M. tuberculosis.

    PubMed

    Nepal, Rajeev M; Mampe, Stephanie; Shaffer, Brian; Erickson, Ann H; Bryant, Paula

    2006-06-01

    Mycobacterium tuberculosis-infected macrophages demonstrate diminished capacity to present antigens via class II MHC molecules. Since successful class II MHC-restricted antigen presentation relies on the actions of endocytic proteases, we asked whether the activities of cathepsins (Cat) B, S and L-three major lysosomal cysteine proteases-are modulated in macrophages infected with pathogenic Mycobacterium spp. Infection of murine bone marrow-derived macrophages with either Mycobacterium avium or M. tuberculosis had no obvious effect on Cat B or Cat S activity. In contrast, the activity of Cat L was altered in infected cells. Specifically, whereas the 24-kDa two-chain mature form of active Cat L predominated in uninfected cells, we observed an increase in the steady-state activity of the precursor single-chain (30 kDa) and 25-kDa two-chain forms of the enzyme in cells infected with either M. avium or M. tuberculosis. Pulse-chase analyses revealed that maturation of nascent, single-chain Cat L into the 25-kDa two-chain form was impaired in infected macrophages, and that maturation into the 24-kDa two-chain form did not occur. Consistent with these data, M. avium infection inhibited the IFNgamma-induced secretion of active two-chain Cat L by macrophages. Viable bacilli were not required to disrupt Cat L maturation, suggesting that a constitutively expressed mycobacterial component was responsible. The absence of the major active form of lysosomal Cat L in M. avium- and M. tuberculosis-infected macrophages may influence the types of T cell epitopes generated in these antigen-presenting cells, and/or the rate of class II MHC peptide loading. PMID:16636015

  5. [Bion-M1. Biological activities of microorganisms under the conditions of a 30-day space flight].

    PubMed

    Voeĭkova, T A; Tiaglov, B V; Novikova, L M; Krest'ianova, I N; Emel'ianova, L K; Korshunov, D V; Morozova, Iu A; Il'in, V K

    2014-01-01

    It was stated that spaceflight factors (SFF) affect the chromosomal DNA interchange during Streptomyces crossing. Cross polarity and primary input of a parent chromosome fragment in recombinant generation imply a more lasting cells contact in microgravity and a broader horizontal transport of genetic material. SFF had no effect on recombination frequency and mutation in a model of parental auxotrophic markers reversion to prototrophism. It was demonstrated that SFF boosted the fC31 phage exit from S. lividans 66 (fC31) and did not influence phage induction in S. coelicolor A3(2) (fC31). SFF inhibited synthesis of antiobiotic actinorhodin in lisogenic S. coelicolor A3(2), and tylosin and desmicosin in S. fradiae. Survivability of electrogenic bacteria Shewanella oneidensis MR-1 in space flight was higher compared with the synchronous control experiment. The reduction activity of S. oneidensis MR-1 as an indicator of electron generation effectiveness was identical in flight and laboratory samples.

  6. Neotuberostemonine attenuates bleomycin-induced pulmonary fibrosis by suppressing the recruitment and activation of macrophages.

    PubMed

    Xiang, Juan; Cheng, Si; Feng, Tianlong; Wu, Yan; Xie, Weina; Zhang, Mian; Xu, Xianghong; Zhang, Chaofeng

    2016-07-01

    Neotuberostemonine (NTS) is one of the main antitussive alkaloids in the root of Stemona tuberosa Lour. This study aimed to investigate the effects of NTS on bleomycin (BLM)-induced pulmonary fibrosis in mice and the underlying mechanism. After BLM administration, NTS were orally administered to mice at 20 and 40mg/kg per day from days 8 to 21, with nintedanib as a positive control. The effect of NTS on BLM-induced mice was assessed via histopathological examination by HE and Masson's trichrome staining, TGF-β1 level and macrophage recruitment by immunohistochemical staining, expression of profibrotic media and M1/M2 polarization by western blot. RAW 264.7 cells were used to evaluate whether NTS (1, 10, 100μM) directly affected macrophages. The results revealed that NTS treatment significantly ameliorated lung histopathological changes and decreased inflammatory cell counts in the bronchoalveolar lavage fluid. The over-expression of collagen, α-SMA and TGF-β1 was reduced by NTS. Furthermore, NTS markedly lowered the expression of MMP-2 and TIMP-1 while raised the expression of MMP-9. A further analysis showed that NTS was able to decrease the recruitment of macrophages and to inhibit the M2 polarization in mice lung tissues. The experiment in vitro showed that NTS significantly reduced the arginase-1 (marker for M2) expression in a dose-dependent manner but down-regulated the iNOS (marker for M1) expression only at 100μM. In conclusion, our study demonstrated for the first time that NTS has a significant protective effect on BLM-induced pulmonary fibrosis through suppressing the recruitment and M2 polarization of macrophages. PMID:27144994

  7. Neotuberostemonine attenuates bleomycin-induced pulmonary fibrosis by suppressing the recruitment and activation of macrophages.

    PubMed

    Xiang, Juan; Cheng, Si; Feng, Tianlong; Wu, Yan; Xie, Weina; Zhang, Mian; Xu, Xianghong; Zhang, Chaofeng

    2016-07-01

    Neotuberostemonine (NTS) is one of the main antitussive alkaloids in the root of Stemona tuberosa Lour. This study aimed to investigate the effects of NTS on bleomycin (BLM)-induced pulmonary fibrosis in mice and the underlying mechanism. After BLM administration, NTS were orally administered to mice at 20 and 40mg/kg per day from days 8 to 21, with nintedanib as a positive control. The effect of NTS on BLM-induced mice was assessed via histopathological examination by HE and Masson's trichrome staining, TGF-β1 level and macrophage recruitment by immunohistochemical staining, expression of profibrotic media and M1/M2 polarization by western blot. RAW 264.7 cells were used to evaluate whether NTS (1, 10, 100μM) directly affected macrophages. The results revealed that NTS treatment significantly ameliorated lung histopathological changes and decreased inflammatory cell counts in the bronchoalveolar lavage fluid. The over-expression of collagen, α-SMA and TGF-β1 was reduced by NTS. Furthermore, NTS markedly lowered the expression of MMP-2 and TIMP-1 while raised the expression of MMP-9. A further analysis showed that NTS was able to decrease the recruitment of macrophages and to inhibit the M2 polarization in mice lung tissues. The experiment in vitro showed that NTS significantly reduced the arginase-1 (marker for M2) expression in a dose-dependent manner but down-regulated the iNOS (marker for M1) expression only at 100μM. In conclusion, our study demonstrated for the first time that NTS has a significant protective effect on BLM-induced pulmonary fibrosis through suppressing the recruitment and M2 polarization of macrophages.

  8. INTERLEUKIN-4- AND INTERLEUKIN-13-MEDIATED ALTERNATIVELY ACTIVATED MACROPHAGES: ROLES IN HOMEOSTASIS AND DISEASE

    PubMed Central

    Van Dyken, Steven J.; Locksley, Richard M.

    2013-01-01

    The macrophage, a versatile cell type prominently involved in host defense and immunity, assumes a distinct state of alternative activation in the context of polarized type 2 immune responses such as allergic inflammation and helminth infection. This alternatively activated phenotype is induced by the canonical type 2 cytokines interleukin (IL)-4 and IL-13, which mediate expression of several characteristic markers along with a dramatic shift in macrophage metabolic pathways that influence surrounding cells and tissues. We discuss recent advances in the understanding of IL-4- and IL-13-mediated alternatively activated macrophages and type 2 immune responses; such advances have led to an expanded appreciation for functions of these cells beyond immunity, including maintenance of physiologic homeostasis and tissue repair. PMID:23298208

  9. 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

  10. [Effect of low-frequency ultrasound on the chemotactic and phagocytic activity of peritoneal macrophages in rats].

    PubMed

    Kochemasova, Z N; Davydova, N V; Matveeva, E A; Dratvin, S A; Lobashevskiĭ, A L

    1983-12-01

    The influence of low-frequency ultrasound on the chemotactic, ingestive and digestive activity of peritoneal macrophages in rats was studied. The intraoperative treatment of the peritoneum with ultrasound enhanced chemotactic activity 3.3-fold in comparison with that in the control animals. The digestive function of peritoneal macrophages considerably increased, the stimulation of their ingestive capacity also occurred. The activation of the phagocytic function of macrophages was observed within 7 days after a single sonar treatment. The authors believe that the stimulation of the macrophage system is probably one of the mechanisms of the sanative action of ultrasound which is used at present in purulent surgery.

  11. Reduced inflammatory activity of RAW 264.7 macrophages on titania nanotube modified Ti surface.

    PubMed

    Neacsu, Patricia; Mazare, Anca; Cimpean, Anisoara; Park, Jung; Costache, Marieta; Schmuki, Patrik; Demetrescu, Ioana

    2014-10-01

    Macrophages play a pivotal role in the hosts response to biomaterials being considered as an essential cell type during both optimal tissue-implant integration and pathologic process of implant failure. Hence, understanding of their cellular activity on biomaterials is important for improving evaluation and design of biomaterials for biomedical applications. In the present study, we have comparatively investigated the interactions of titania nanotubes (78 nm diameter) and commercial pure Ti with RAW 264.7 macrophages in both standard and pro-inflammatory (stimulation with lipopolysaccharide, LPS) culture conditions. In vitro tests showed that TiO2 nanotubes exhibited significantly decreased inflammatory activity of macrophages with respect to cytokine and chemokine gene expression/protein secretion, induction of foreign body giant cells (FBGCs) and nitric oxide (NO) release thereby mitigating the inflammatory response induced by LPS as compared to flat Ti surface. Therefore, our results suggest a novel role of TiO2 nanotubes in modulating macrophage response in biomaterial-associated bacterial infections. Overall, the current study provides new insight into how TiO2 nanotubes can be involved in macrophage activation and supports the great promise of such surface modifications for biomedical applications.

  12. 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.

  13. 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

  14. Antiatherogenic activity of fungal beauveriolides, inhibitors of lipid droplet accumulation in macrophages

    PubMed Central

    Namatame, Ichiji; Tomoda, Hiroshi; Ishibashi, Shun; Ōmura, Satoshi

    2004-01-01

    Beauveriolides I and III, isolated from the culture broth of fungal Beauveria sp. FO-6979, showed potent inhibitory activity of lipid droplet accumulation in primary mouse peritoneal macrophages. The cellular molecular target of this inhibitory activity was studied in macrophages. Beauveriolides I and III strongly inhibited the cholesteryl ester (CE) synthesis with IC50 values of 0.78 and 0.41 μM, respectively, without showing significant effects on the triacylglycerol and phospholipid synthesis. Furthermore, lysosomal cholesterol metabolism to CE in macrophages was inhibited by the compounds, indicating that the inhibition site lies within steps between cholesterol departure from the lysosome and CE synthesis in the endoplasmic reticulum. Therefore, acyl-CoA:cholesterol acyltransferase (ACAT) activity in the membrane fractions prepared from mouse macrophages was studied, resulting in a dose-dependent inhibition by beauveriolides I and III with IC50 values of 6.0 and 5.5 μM, respectively. Thus, we showed that the beauveriolides inhibit macrophage ACAT activity specifically, resulting in blockage of the CE synthesis, leading to a reduction of lipid droplets in macrophages. ACAT activity in the membrane fractions prepared from mouse liver and Caco-2 cells was also inhibited, indicating that the beauveriolides block both ACAT-1 and -2. Moreover, beauveriolides I and III exert antiatherogenic activity in both low-density lipoprotein receptor- and apolipoprotein E-knockout mice without any side effects such as diarrhea or cytotoxicity to adrenal tissues as observed for many synthetic ACAT inhibitors. Beauveriolides I and III are the first microbial cyclodepsipeptides having an in vivo antiatherosclerotic effect and show promise as potential lead compounds for antiatherosclerotic agents. PMID:14718664

  15. Macrophage polarization in response to ECM coated polypropylene mesh

    PubMed Central

    Wolf, MT; Dearth, CL; Ranallo, CA; LoPresti, S; Carey, LE; Daly, KA; Brown, BN; Badylak, SF

    2015-01-01

    The host response to implanted biomaterials is a highly regulated process that influences device functionality and clinical outcome. Non-degradable biomaterials, such as knitted polypropylene mesh, frequently elicit a chronic foreign body reaction with resultant fibrosis. Previous studies have shown that an extracellular matrix (ECM) hydrogel coating of polypropylene mesh reduces the intensity of the foreign body reaction, though the mode of action is unknown. Macrophage participation plays a key role in the development of the foreign body reaction to biomaterials, and therefore the present study investigated macrophage polarization following mesh implantation. Spatiotemporal analysis of macrophage polarization was conducted in response to uncoated polypropylene mesh and mesh coated with hydrated and dry forms of ECM hydrogels derived from either dermis or urinary bladder. Pro-inflammatory M1 macrophages (CD86+/CD68+), alternatively activated M2 macrophages (CD206+/CD68+), and foreign body giant cells were quantified between 3-35 days. Uncoated polypropylene mesh elicited a dominant M1 response at the mesh fiber surface, which was decreased by each ECM coating type beginning at 7 days. The diminished M1 response was accompanied by a reduction in the number of foreign body giant cells at 14 and 35 days, though there was a minimal effect upon the number of M2 macrophages at any time. These results show that ECM coatings attenuate the M1 macrophage response and increase the M2/M1 ratio to polypropylene mesh in vivo. PMID:24856104

  16. Pentamethoxyflavanone regulates macrophage polarization and ameliorates sepsis in mice.

    PubMed

    Feng, Lili; Song, Pingping; Zhou, Hang; Li, Ang; Ma, Yuxiang; Zhang, Xiong; Liu, Hailiang; Xu, Ge; Zhou, Yang; Wu, Xuefeng; Shen, Yan; Sun, Yang; Wu, Xudong; Xu, Qiang

    2014-05-01

    Macrophages, owning variable phenotypes and diverse functions, were becoming the target cells in inflammatory, infectious and autoimmune diseases. In the present study, we evaluated the effect of 5,7,3',4',5'-pentamethoxyflavanone (abbreviated as PMFA), a kind of flavonoid, on macrophage polarization, and investigated the underlying mechanism. We found that PMFA significantly inhibited M1 macrophage polarization and diminished the proinflammatory cytokines, meanwhile it greatly enhanced M2 macrophage related molecules. Moreover, PMFA facilitated the phenotype shift from M1 to M2. However, PMFA only slightly inhibited the activation of T and B cells. Further researches showed that the mechanisms can be attributed to PMFA's down-regulation on p-STAT1 and up-regulation on p-STAT6, the pivotal regulatory molecules for M1 and M2 polarization, respectively. In addition, PMFA ameliorated LPS- and cecal ligation and puncture (CLP)-induced sepsis in mice, as assessed by the raise of survival rate, descend of tissue damage and bronchoalveolar lavage fluid (BALF) cytokines. PMFA significantly decreased the expression of IL-1β, IL-6 and TNF-α and reduced the infiltration of M1 macrophages in lung. As expected, adoptive transfer of PMFA-pretreated M1 macrophages significantly increased survival rate of LPS-challenged mice compared with control mice. Taken together, the results indicate that PMFA regulates macrophage polarization via targeting the STAT1/STAT6 signals and its potential use in treatment of inflammatory disease.

  17. Functional dichotomy in the 16S rRNA (m1A1408) methyltransferase family and control of catalytic activity via a novel tryptophan mediated loop reorganization.

    PubMed

    Witek, Marta A; Conn, Graeme L

    2016-01-01

    Methylation of the bacterial small ribosomal subunit (16S) rRNA on the N1 position of A1408 confers exceptionally high-level resistance to a broad spectrum of aminoglycoside antibiotics. Here, we present a detailed structural and functional analysis of the Catenulisporales acidiphilia 16S rRNA (m(1)A1408) methyltransferase ('CacKam'). The apo CacKam structure closely resembles other m(1)A1408 methyltransferases within its conserved SAM-binding fold but the region linking core β strands 6 and 7 (the 'β6/7 linker') has a unique, extended structure that partially occludes the putative 16S rRNA binding surface, and sequesters the conserved and functionally critical W203 outside of the CacKam active site. Substitution of conserved residues in the SAM binding pocket reveals a functional dichotomy in the 16S rRNA (m(1)A1408) methyltransferase family, with two apparently distinct molecular mechanisms coupling cosubstrate/ substrate binding to catalytic activity. Our results additionally suggest that CacKam exploits the W203-mediated remodeling of the β6/7 linker as a novel mechanism to control 30S substrate recognition and enzymatic turnover.

  18. Classical and alternative macrophage activation in the lung following ozone-induced oxidative stress

    SciTech Connect

    Sunil, Vasanthi R.; Patel-Vayas, Kinal; Shen, Jianliang; Laskin, Jeffrey D.; Laskin, Debra L.

    2012-09-01

    Ozone is a pulmonary irritant known to cause oxidative stress, inflammation and tissue injury. Evidence suggests that macrophages play a role in the pathogenic response; however, their contribution depends on the mediators they encounter in the lung which dictate their function. In these studies we analyzed the effects of ozone-induced oxidative stress on the phenotype of alveolar macrophages (AM). Exposure of rats to ozone (2 ppm, 3 h) resulted in increased expression of 8-hydroxy-2′-deoxyguanosine (8-OHdG), as well as heme oxygenase-1 (HO-1) in AM. Whereas 8-OHdG was maximum at 24 h, expression of HO-1 was biphasic increasing after 3 h and 48–72 h. Cleaved caspase-9 and beclin-1, markers of apoptosis and autophagy, were also induced in AM 24 h post-ozone. This was associated with increased bronchoalveolar lavage protein and cells, as well as matrix metalloproteinase (MMP)-2 and MMP-9, demonstrating alveolar epithelial injury. Ozone intoxication resulted in biphasic activation of the transcription factor, NFκB. This correlated with expression of monocyte chemotactic protein‐1, inducible nitric oxide synthase and cyclooxygenase‐2, markers of proinflammatory macrophages. Increases in arginase-1, Ym1 and galectin-3 positive anti-inflammatory/wound repair macrophages were also observed in the lung after ozone inhalation, beginning at 24 h (arginase-1, Ym1), and persisting for 72 h (galectin-3). This was associated with increased expression of pro-surfactant protein-C, a marker of Type II cell proliferation and activation, important steps in wound repair. These data suggest that both proinflammatory/cytotoxic and anti-inflammatory/wound repair macrophages are activated early in the response to ozone-induced oxidative stress and tissue injury. -- Highlights: ► Lung macrophages are highly sensitive to ozone induced oxidative stress. ► Ozone induces autophagy and apoptosis in lung macrophages. ► Proinflammatory and wound repair macrophages are activated

  19. Tissue factor activity. A marker of alveolar macrophage maturation in rabbits. Effects of granulomatous pneumonitis.

    PubMed Central

    Rothberger, H; McGee, M P; Lee, T K

    1984-01-01

    Experiments were carried out to examine relationships between alveolar macrophage maturity and amounts of tissue factor (Clotting Factor III) in these cells under physiologic conditions and during immunologically induced pneumonitis. Using discontinuous density gradient centrifugation, alveolar macrophages from healthy rabbits were rapidly isolated into five subpopulations at different stages of maturation, as demonstrated by morphologic and morphometric evaluation. Very large amounts of tissue factor activity were found in fully mature cells that were purified in the lowest density subpopulation and assayed without preliminary in vitro stimulation or culture. In the remaining four subpopulations of increasing density, amounts of tissue factor were found to progressively diminish in direct correlation with declines of cell maturity. These differences at mean levels were as great as 35-fold. In addition, blood monocytes had less than 1/219 and less than 1/6 of the activity of the fully mature and the least mature subpopulations, respectively. After 16 h culture of the five isolated subpopulations in the absence of lymphokines or of significant numbers of lymphocytes, tissue factor activity increased in inverse correlation with the preincubation stage of cell maturity (2,387 and 109% in the least mature and most mature subpopulations, respectively). These increases required protein synthesis and were accompanied by morphologic and morphometric changes which indicated cellular maturation during the period of tissue factor activity generation in vitro, thus further demonstrating relationships between macrophage maturity and tissue factor content. In additional experiments, direct correlations between cell maturity and tissue factor activity content were also found in activated alveolar macrophage populations from rabbits with Bacillus Calmette Guering (BCG)-induced granulomatous pneumonitis. However, as compared with controls, the BCG populations had increased total

  20. Signaling events during macrophage activation with Betula pendula roth pectic polysaccharides.

    PubMed

    Ligacheva, A A; Danilets, M G; Trofimova, E S; Belsky, Y P; Belska, N V; Zyuz'kov, G N; Zhdanov, V V; Ivanova, A N; Guriev, A M; Belousov, M V; Yusubov, M S; Dygai, A M

    2014-02-01

    We studied the effect of two pectic polysaccharides PS-B1-AG and PS-B2-RG that were contained in total polysaccharides extracted from Betula pendula leaves on NO production by mouse macrophages and the contribution of signaling molecules to macrophage activation by the test substances. Unlike the total sample, pectins produced a NO-stimulating effect on macrophages. The effect of PS-B2-RG (10 μg/ml) did not differ from the effect of LPS, while PS-B1-AG produced this effect only in a concentration of 20 μg/ml, which was probably due to differences in the chemical structure of the test substances. The studied pectin polysaccharides activated transcription factor NF-κB, kinases p38 and PI3, and cAMP as a negative regulator. These results indicate that Betula pendula polysaccharides are promising substances for creation of immunomodulating drugs.

  1. Vessel-associated myogenic precursors control macrophage activation and clearance of apoptotic cells.

    PubMed

    Bosurgi, L; Brunelli, S; Rigamonti, E; Monno, A; Manfredi, A A; Rovere-Querini, P

    2015-01-01

    Swift and regulated clearance of apoptotic cells prevents the accumulation of cell remnants in injured tissues and contributes to the shift of macrophages towards alternatively activated reparatory cells that sustain wound healing. Environmental signals, most of which are unknown, in turn control the efficiency of the clearance of apoptotic cells and as such determine whether tissues eventually heal. In this study we show that vessel-associated stem cells (mesoangioblasts) specifically modulate the expression of genes involved in the clearance of apoptotic cells and in macrophage alternative activation, including those of scavenger receptors and of molecules that bridge dying cells and phagocytes. Mesoangioblasts, but not immortalized myoblasts or neural precursor cells, enhance CD163 membrane expression in vitro as assessed by flow cytometry, indicating that the effect is specific. Mesoangioblasts transplanted in acutely or chronically injured skeletal muscles determine the expansion of the population of CD163(+) infiltrating macrophages and increase the extent of CD163 expression. Conversely, macrophages challenged with mesoangioblasts engulf significantly better apoptotic cells in vitro. Collectively, the data reveal a feed-forward loop between macrophages and vessel-associated stem cells, which has implications for the skeletal muscle homeostatic response to sterile injury and for diseases in which homeostasis is jeopardized, including muscle dystrophies and inflammatory myopathies. PMID:24749786

  2. Macrophages, Meta-Inflammation, and Immuno-Metabolism

    PubMed Central

    Shapiro, Haim; Lutaty, Aviv; Ariel, Amiram

    2011-01-01

    Current research depicts specific modes of immunity and energy metabolism as being interrelated at the molecular, cellular, organ and organism level. Hence, whereas M2 (alternatively-activated) macrophages dominate insulin-sensitive adipose tissue in the lean, M1-skewed (classically-activated) macrophages accumulate in parallel to adiposity in the obese, and promote inflammation and insulin resistance, that is, meta-inflammation. The latest frontier of immuno-metabolism explores the coregulation of energy metabolism and immune function within hematopoietic cells. M1-skewed macrophages are sustained in edematous, hypoxic tissues by anaerobic glycolysis, whereas mitochondrial biogenesis and respiration dominates in M2 cells. We review the underlying mechanisms and the consequences of the transition from M2 to M1 predominance in adipose tissue, as well as the extracellular signals and transcription factors that control macrophage phenotypes and impose distinct metabolic modes. PMID:22235182

  3. 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. PMID:25650776

  4. 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.

  5. Dimethyl sulfoxide modulates NF-kappa B and cytokine activation in lipopolysaccharide-treated murine macrophages.

    PubMed Central

    Kelly, K A; Hill, M R; Youkhana, K; Wanker, F; Gimble, J M

    1994-01-01

    Antioxidants are protective against septic shock in animal models. Recently, free radical scavengers have been found to inhibit the activation of the NF-kappa B protein in a number of cell lines. This transcriptional regulatory protein binds to the promoters of the proinflammatory cytokines tumor necrosis factor, interleukin-6, and the macrophage inflammatory proteins. The current work examined lipopolysaccharide-induced NF-kappa B activation in the J774 macrophage-like cell line and primary peritoneal macrophages from lipopolysaccharide-responsive (C3HeB/Fej) and -nonresponsive (C3H/HeJ) murine strains. The DNA-binding activity of the NF-kappa B protein directly correlated with mRNA expression for the genes encoding the proinflammatory cytokines and the free radical scavenging enzyme, superoxide dismutase. Both the p50 and p65 NF-kappa B subunits were detected on gel supershift assays. Minimal NF-kappa B activity was observed following exposure of C3H/HeJ macrophages to lipopolysaccharide. The antioxidant dimethyl sulfoxide decreased the level of NF-kappa B activation in the J774 cells. This correlated with decreased expression of cytokine mRNAs and tumor necrosis factor bioactivity. These results suggest that modulation of NF-kappa B activation may provide a mechanism through which antioxidants protect against endotoxemia in murine models. Images PMID:8039880

  6. Comparative activation states of tumor-associated and peritoneal macrophages from mice bearing an induced fibrosarcoma.

    PubMed

    Valdez, J C; de Alderete, N; Meson, O E; Sirena, A; Perdigon, G

    1990-11-01

    Balb/c mice bearing a methylcholanthrene-induced fibrosarcoma were used to compare the activation levels of tumor-associated and peritoneal macrophages. Two stages of tumor growth were examined, namely "small" and "large" tumors, with average diameters of 10 and 30 mm, respectively. The activation state, determined by measurement of both phagocytic index and beta-glucuronidase content, was found to be markedly higher in tumor-associated macrophages than in their peritoneal counterparts and it was, in addition, independent of tumor progression. The percentage of tumor-associated macrophages, which were detected on the basis of Fc receptor expression, remained constant in the growing neoplasm, at approximately 23% of total cell population. None of these parameters were affected by inoculation with an immunopotentiating dose of heat-killed Candida albicans which, on the other hand, seemed not to alter the course of the tumor. These data suggest that within the tumor microenvironment macrophages would somehow be maintained at a constant proportion and at a highly activated state, while outside the tumor they would be at a lower activation level. Our results also suggest that TAM would not possess antitumor activity in vivo, although we have found this activity in vitro.

  7. Comparative activation states of tumor-associated and peritoneal macrophages from mice bearing an induced fibrosarcoma.

    PubMed

    Valdez, J C; de Alderete, N; Meson, O E; Sirena, A; Perdigon, G

    1990-11-01

    Balb/c mice bearing a methylcholanthrene-induced fibrosarcoma were used to compare the activation levels of tumor-associated and peritoneal macrophages. Two stages of tumor growth were examined, namely "small" and "large" tumors, with average diameters of 10 and 30 mm, respectively. The activation state, determined by measurement of both phagocytic index and beta-glucuronidase content, was found to be markedly higher in tumor-associated macrophages than in their peritoneal counterparts and it was, in addition, independent of tumor progression. The percentage of tumor-associated macrophages, which were detected on the basis of Fc receptor expression, remained constant in the growing neoplasm, at approximately 23% of total cell population. None of these parameters were affected by inoculation with an immunopotentiating dose of heat-killed Candida albicans which, on the other hand, seemed not to alter the course of the tumor. These data suggest that within the tumor microenvironment macrophages would somehow be maintained at a constant proportion and at a highly activated state, while outside the tumor they would be at a lower activation level. Our results also suggest that TAM would not possess antitumor activity in vivo, although we have found this activity in vitro. PMID:2099903

  8. Regulation of macrophage-mediated larvicidal activity in Echinococcus granulosus and Mesocestoides corti (Cestoda) infection in mice.

    PubMed

    Jenkins, P; Dixon, J B; Rakha, N K; Carter, S D

    1990-04-01

    Killing of metacestodes by normal or post-infection macrophages and the regulation of this activity by cytokines were studied in vitro. The protoscolecidal activity of normal macrophages against Echinococcus granulosus was inhibited by a product of naive T-enriched lymphocytes co-cultured with protoscoleces (PSC). By contrast, supernates from co-cultures of Mesocestoides corti tetrathyridia (MCT) and T-enriched or B-enriched normal lymphocytes increased killing of MCT by normal macrophages. Larvicidal activity (against both PSC and MCT) was enhanced by high concentrations of macrophage-activating factors produced by Con A-stimulated rat lymphocytes (Con A-LK), but was reduced by low concentrations of these factors. Activation by synergism between Con A-LK and recombinant interferon-gamma(r. IFN-gamma) was demonstrated in macrophage-mediated killing of MCT at high effector to target ratio. Cytokine-activation of normal or post-MCT infection macrophages was compared. Macrophages from both 8 and 20 week post-infection mice were refractory to lymphokines from lymphocyte-MCT cultures and displayed greatly reduced killing of MCT. Macrophage activation by Con A-LK and r.IFN-gamma was also impaired, implying a general defect in the ability of these post-infection macrophages to respond to macrophage activating signals. The data indicate that two different mechanisms may exist by which metacestodes regulate potentially larvicidal effector mechanisms. E. granulosus can elicit the production of lymphokines suppressive for PSC killing, whereas M. corti appears directly to induce a refractory state in effector macrophages.

  9. The Role of Macrophage Derived Urokinase Plasminogen Activator in Myocardial Infarct Repair

    PubMed Central

    Minami, Elina; Castellani, Chiara; Malchodi, Laura; Deem, Jennifer; Bertko, Kate; Meznarich, Jessica; Dishmon, Monja; Murry, Charles E.; Stempien-Otero, April

    2011-01-01

    Cardiac plasmin activity is increased following myocardial ischemia. To test the hypothesis that macrophage-derived uPA is a key mediator of repair following myocardial infarction we performed myocardial infarction on mice with macrophage specific over-expression of uPA (SR-uPA mice). SR-uPA+/0 mice and wild-type littermates were sacrificed at 5 days or 4 weeks after infarction and cardiac content of macrophages, collagen, and myofibroblasts was quantified. Cardiac function and dimensions were assessed by echocardiography at baseline and at 4 weeks post-infarction. At 4 weeks after myocardial infarction, macrophage counts were increased in SR-uPA+/0 mice in the infarct (13.1 vs. 4.9 %, P < 0.001) and distant uninfarcted regions (5.9 vs. 2.4%, P < 0.001). Infarct scar was thicker in SR-uPA+/0 mice (0.54 ± 0.03mm vs. 0.45 ± 0.03mm, P <0.05) and infarct cardiac collagen content was increased (72.4 ± 3.3% vs. 63.0 ± 3.6%, P < 0.06). Functionally, these changes resulted in mildly improved fractional shortening in SR-uPA+/o mice compared to controls (24.6 ±1.68 vs. 19.8 ± 1.3% P = 0.03). At 5 days after infarction there was increased collagen content in the scar without increases in macrophages or myofibroblasts. To understand the mechanisms by which macrophage derived uPA increases collagen, cardiac fibroblasts were treated with macrophage conditioned medium or plasmin and expression of ColIα1 measured by qPCR. Conditioned media from SR-uPA+/o or plasmin-treated nontransgenic macrophages but not plasmin alone increased collagen expression in isolated cardiac fibroblasts. We hypothesize that plasmin generation in the heart in response to injury may induce activation of macrophages to a profibrotic phenotype to allow rapid formation of collagenous scar. PMID:20380835

  10. Identification of cyclophilin as a proinflammatory secretory product of lipopolysaccharide-activated macrophages.

    PubMed Central

    Sherry, B; Yarlett, N; Strupp, A; Cerami, A

    1992-01-01

    We have isolated an 18-kDa peptide (designated sp18, for 18-kDa secreted protein) from the conditioned medium of lipopolysaccharide-stimulated RAW 264.7 murine macrophages. Purified sp18 had in vivo inflammatory activity and in vitro chemotactic activity for human peripheral blood polymorphonuclear leukocytes and monocytes. Surprisingly, N-terminal sequencing and tryptic mapping studies revealed that sp18 and cyclophilin, an intracellular protein that binds the immunosuppressive drug cyclosporin A, are highly homologous. The in vitro chemotactic activity of sp18 on monocytes was blocked by cyclosporin A but not by cyclosporin H, a structural analog of cyclosporin A that does not bind cyclophilin. Like purified porcine cyclophilin, mouse sp18 exhibited peptidyl-prolyl cis-trans isomerase activity. Medium conditioned by lipopolysaccharide-stimulated resident peritoneal exudate macrophages isolated from C57BL/6 mice contained substantially higher levels of sp18/cyclophilin than medium conditioned by nonstimulated macrophages. The observation that sp18/cyclophilin exhibits proinflammatory activity and is secreted by macrophages in response to endotoxin suggests that this protein may function as a cytokine, and invites the hypothesis that the immunosuppressive action of cyclosporin A results in part from interaction with an extracellular form of cyclophilin released as a mediator of immune and inflammatory functions. Images PMID:1565646

  11. Epigenetic regulation of macrophage polarization by DNA methyltransferase 3b.

    PubMed

    Yang, Xiaosong; Wang, Xianfeng; Liu, Dongxu; Yu, Liqing; Xue, Bingzhong; Shi, Hang

    2014-04-01

    Adipose tissue macrophages (ATMs) undergo a phenotypic switch from alternatively activated antiinflammatory M2 macrophages in lean individuals to classically activated proinflammatory M1 macrophages in obese subjects. However, the molecular mechanism underlying this process remains unclear. In this study we aim to determine whether DNA methyltransferase 3b (DNMT3b) regulates macrophage polarization and inflammation. We found that the expression of DNMT3b was significantly induced in macrophages exposed to the saturated fatty acid stearate, was higher in ATMs isolated from obese mice, but was significantly lower in alternatively activated M2 vs classically activated M1 ATMs, suggesting a role for DNMT3b in regulation of macrophage polarization and inflammation in obesity. DNMT3b knockdown promoted macrophage polarization to alternatively activated M2 phenotype and suppressed macrophage inflammation, whereas overexpressing DNMT3b did the opposite. Importantly, in a macrophage-adipocyte coculture system, we found that DNMT3b knockdown significantly improved adipocyte insulin signaling. The promoter of peroxisome proliferator activated receptor (PPAR)γ1, a key transcriptional factor that regulates macrophage polarization, is enriched with CpG sites. Chromatin immunoprecipitation assays showed that DNMT3b bound to the methylation region at PPARγ1 promoter, which was further enhanced by stearate. Moreover, pyrosequencing analysis revealed that stearate increased DNA methylation at PPARγ1, which was prevented by DNMT3b deficiency. Therefore, our data demonstrate that DNMT3b plays an important role in regulating macrophage polarization through epigenetic mechanisms. In obesity, elevated saturated fatty acids enhance DNMT3b expression, leading to DNA methylation at the PPARγ1 promoter, which may contribute to deregulated adipose tissue macrophage polarization, inflammation, and insulin resistance.

  12. Cutting Edge: Inflammasome Activation in Primary Human Macrophages Is Dependent on Flagellin

    PubMed Central

    Kortmann, Jens; Brubaker, Sky W.

    2015-01-01

    Murine NLR family, apoptosis inhibitory protein (Naip)1, Naip2, and Naip5/6 are host sensors that detect the cytosolic presence of needle and rod proteins from bacterial type III secretion systems and flagellin, respectively. Previous studies using human-derived macrophage-like cell lines indicate that human macrophages sense the cytosolic needle protein, but not bacterial flagellin. In this study, we show that primary human macrophages readily sense cytosolic flagellin. Infection of primary human macrophages with Salmonella elicits robust cell death and IL-1β secretion that is dependent on flagellin. We show that flagellin detection requires a full-length isoform of human Naip. This full-length Naip isoform is robustly expressed in primary macrophages from healthy human donors, but it is drastically reduced in monocytic tumor cells, THP-1, and U937, rendering them insensitive to cytosolic flagellin. However, ectopic expression of full-length Naip rescues the ability of U937 cells to sense flagellin. In conclusion, human Naip functions to activate the inflammasome in response to flagellin, similar to murine Naip5/6. PMID:26109648

  13. 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

  14. Autophagy deficiency in macrophages enhances NLRP3 inflammasome activity and chronic lung disease following silica exposure.

    PubMed

    Jessop, Forrest; Hamilton, Raymond F; Rhoderick, Joseph F; Shaw, Pamela K; Holian, Andrij

    2016-10-15

    Autophagy is an important metabolic mechanism that can promote cellular survival following injury. The specific contribution of autophagy to silica-induced inflammation and disease is not known. The objective of these studies was to determine the effects of silica exposure on the autophagic pathway in macrophages, as well as the general contribution of autophagy in macrophages to inflammation and disease. Silica exposure enhanced autophagic activity in vitro in Bone Marrow derived Macrophages and in vivo in Alveolar Macrophages isolated from silica-exposed mice. Impairment of autophagy in myeloid cells in vivo using Atg5(fl/fl)LysM-Cre(+) mice resulted in enhanced cytotoxicity and inflammation after silica exposure compared to littermate controls, including elevated IL-18 and the alarmin HMGB1 in the whole lavage fluid. Autophagy deficiency caused some spontaneous inflammation and disease. Greater silica-induced acute inflammation in Atg5(fl/fl)LysM-Cre(+) mice correlated with increased fibrosis and chronic lung disease. These studies demonstrate a critical role for autophagy in suppressing silica-induced cytotoxicity and inflammation in disease development. Furthermore, this data highlights the importance of basal autophagy in macrophages and other myeloid cells in maintaining lung homeostasis.

  15. Cutting Edge: Inflammasome Activation in Primary Human Macrophages Is Dependent on Flagellin.

    PubMed

    Kortmann, Jens; Brubaker, Sky W; Monack, Denise M

    2015-08-01

    Murine NLR family, apoptosis inhibitory protein (Naip)1, Naip2, and Naip5/6 are host sensors that detect the cytosolic presence of needle and rod proteins from bacterial type III secretion systems and flagellin, respectively. Previous studies using human-derived macrophage-like cell lines indicate that human macrophages sense the cytosolic needle protein, but not bacterial flagellin. In this study, we show that primary human macrophages readily sense cytosolic flagellin. Infection of primary human macrophages with Salmonella elicits robust cell death and IL-1β secretion that is dependent on flagellin. We show that flagellin detection requires a full-length isoform of human Naip. This full-length Naip isoform is robustly expressed in primary macrophages from healthy human donors, but it is drastically reduced in monocytic tumor cells, THP-1, and U937, rendering them insensitive to cytosolic flagellin. However, ectopic expression of full-length Naip rescues the ability of U937 cells to sense flagellin. In conclusion, human Naip functions to activate the inflammasome in response to flagellin, similar to murine Naip5/6. PMID:26109648

  16. Autophagy deficiency in macrophages enhances NLRP3 inflammasome activity and chronic lung disease following silica exposure.

    PubMed

    Jessop, Forrest; Hamilton, Raymond F; Rhoderick, Joseph F; Shaw, Pamela K; Holian, Andrij

    2016-10-15

    Autophagy is an important metabolic mechanism that can promote cellular survival following injury. The specific contribution of autophagy to silica-induced inflammation and disease is not known. The objective of these studies was to determine the effects of silica exposure on the autophagic pathway in macrophages, as well as the general contribution of autophagy in macrophages to inflammation and disease. Silica exposure enhanced autophagic activity in vitro in Bone Marrow derived Macrophages and in vivo in Alveolar Macrophages isolated from silica-exposed mice. Impairment of autophagy in myeloid cells in vivo using Atg5(fl/fl)LysM-Cre(+) mice resulted in enhanced cytotoxicity and inflammation after silica exposure compared to littermate controls, including elevated IL-18 and the alarmin HMGB1 in the whole lavage fluid. Autophagy deficiency caused some spontaneous inflammation and disease. Greater silica-induced acute inflammation in Atg5(fl/fl)LysM-Cre(+) mice correlated with increased fibrosis and chronic lung disease. These studies demonstrate a critical role for autophagy in suppressing silica-induced cytotoxicity and inflammation in disease development. Furthermore, this data highlights the importance of basal autophagy in macrophages and other myeloid cells in maintaining lung homeostasis. PMID:27594529

  17. Serum factors, cell membrane CD14, and beta2 integrins are not required for activation of bovine macrophages by lipopolysaccharide.

    PubMed Central

    Jungi, T W; Sager, H; Adler, H; Brcic, M; Pfister, H

    1997-01-01

    The role of serum factors such as lipopolysaccharide (LPS)-binding protein (LBP) and of macrophage-expressed CD14 and beta2 integrins in the activation of bovine macrophages by LPS was investigated. Macrophage activation was determined by measuring tumor necrosis factor production, NO generation, and upregulation of procoagulant activity by LPS (Escherichia coli O55:B5) at concentrations of 100 pg/ml to 100 ng/ml. The 50% effective dose for LPS was 1 order of magnitude higher than that for activating human macrophages. Macrophages were activated by LPS in the presence of serum or in the presence of albumin demonstrated to be free of LBP. The capacity to react to LPS in the absence of LBP was not due to the acquisition of LBP during a previous culture in serum. It was then established which CD14-specific antibodies block LPS binding to monocytes. Among the CD14-specific antibodies recognizing bovine mononuclear phagocytes (60bca, 3C10, My4, CAM36, VPM65, CMRF31, and TUK4), the first four blocked the binding of LPS-fluorescein isothiocyanate to bovine monocytes at low concentrations. Anti-CD14 antibodies did not block LPS-mediated activation of bovine bone marrow-derived macrophages, monocyte-derived macrophages, and alveolar macrophages. This was observed in experiments in which anti-CD14 concentrations exceeded the 50% inhibitory dose by >30-fold (3C10 and My4) or >300-fold (60bca), as defined in the binding assay described above. Monocyte-derived macrophages from an animal deficient in beta2 integrins and control macrophages were activated by similar concentrations of LPS, suggesting that beta2 integrins are not important bovine LPS receptors. Thus, in bovine macrophages, LPS recognition pathways which are independent of exogenous LBP, of membrane-expressed CD14, and of beta2 integrins may exist. PMID:9284122

  18. The Reactive Oxygen Species in Macrophage Polarization: Reflecting Its Dual Role in Progression and Treatment of Human Diseases.

    PubMed

    Tan, Hor-Yue; Wang, Ning; Li, Sha; Hong, Ming; Wang, Xuanbin; Feng, Yibin

    2016-01-01

    High heterogeneity of macrophage is associated with its functions in polarization to different functional phenotypes depending on environmental cues. Macrophages remain in balanced state in healthy subject and thus macrophage polarization may be crucial in determining the tissue fate. The two distinct populations, classically M1 and alternatively M2 activated, representing the opposing ends of the full activation spectrum, have been extensively studied for their associations with several disease progressions. Accumulating evidences have postulated that the redox signalling has implication in macrophage polarization and the key roles of M1 and M2 macrophages in tissue environment have provided the clue for the reasons of ROS abundance in certain phenotype. M1 macrophages majorly clearing the pathogens and ROS may be crucial for the regulation of M1 phenotype, whereas M2 macrophages resolve inflammation which favours oxidative metabolism. Therefore how ROS play its role in maintaining the homeostatic functions of macrophage and in particular macrophage polarization will be reviewed here. We also review the biology of macrophage polarization and the disturbance of M1/M2 balance in human diseases. The potential therapeutic opportunities targeting ROS will also be discussed, hoping to provide insights for development of target-specific delivery system or immunomodulatory antioxidant for the treatment of ROS-related diseases.

  19. The Reactive Oxygen Species in Macrophage Polarization: Reflecting Its Dual Role in Progression and Treatment of Human Diseases

    PubMed Central

    Tan, Hor-Yue; Li, Sha; Hong, Ming; Wang, Xuanbin

    2016-01-01

    High heterogeneity of macrophage is associated with its functions in polarization to different functional phenotypes depending on environmental cues. Macrophages remain in balanced state in healthy subject and thus macrophage polarization may be crucial in determining the tissue fate. The two distinct populations, classically M1 and alternatively M2 activated, representing the opposing ends of the full activation spectrum, have been extensively studied for their associations with several disease progressions. Accumulating evidences have postulated that the redox signalling has implication in macrophage polarization and the key roles of M1 and M2 macrophages in tissue environment have provided the clue for the reasons of ROS abundance in certain phenotype. M1 macrophages majorly clearing the pathogens and ROS may be crucial for the regulation of M1 phenotype, whereas M2 macrophages resolve inflammation which favours oxidative metabolism. Therefore how ROS play its role in maintaining the homeostatic functions of macrophage and in particular macrophage polarization will be reviewed here. We also review the biology of macrophage polarization and the disturbance of M1/M2 balance in human diseases. The potential therapeutic opportunities targeting ROS will also be discussed, hoping to provide insights for development of target-specific delivery system or immunomodulatory antioxidant for the treatment of ROS-related diseases. PMID:27143992

  20. Regulation of inflammation-primed activation of macrophages by two serum factors, vitamin D3-binding protein and albumin.

    PubMed Central

    Yamamoto, N; Kumashiro, R; Yamamoto, M; Willett, N P; Lindsay, D D

    1993-01-01

    A very small amount (0.0005 to 0.001%) of an ammonium sulfate [50% saturated (NH4)2SO4]-precipitable protein fraction of alpha 2-globulin efficiently supported inflammation-primed activation of macrophages. This fraction contains vitamin D3-binding protein essential for macrophage activation. Comparative macrophage activation studies with fetal calf serum, alpha 2-globulin fraction, 50% (NH4)2SO4 precipitate, and purified bovine vitamin D3-binding protein revealed that fetal calf serum and alpha 2-globulin fraction appear to contain an inhibitor for macrophage activation while ammonium sulfate precipitate contains no inhibitor. This inhibitor was found to be serum albumin. When bovine serum albumin (25 micrograms/ml) was added to a medium supplemented with 0.0005 to 0.05% (NH4)2SO4 precipitate or 1 to 10 ng of vitamin D3-binding protein per ml, activation of macrophages was inhibited. PMID:8225612

  1. 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.

  2. Autocrine IL-10 activation of the STAT3 pathway is required for pathological macrophage differentiation in polycystic kidney disease

    PubMed Central

    Peda, Jacqueline D.; Salah, Sally M.; Wallace, Darren P.; Fields, Patrick E.; Grantham, Connor J.; Fields, Timothy A.

    2016-01-01

    ABSTRACT Polycystic kidney disease (PKD) is characterized by slow expansion of fluid-filled cysts derived from tubules within the kidney. Cystic expansion results in injury to surrounding parenchyma and leads to inflammation, scarring and ultimately loss of renal function. Macrophages are a key element in this process, promoting cyst epithelial cell proliferation, cyst expansion and disease progression. Previously, we have shown that the microenvironment established by cystic epithelial cells can ‘program’ macrophages, inducing M2-like macrophage polarization that is characterized by expression of markers that include Arg1 and Il10. Here, we functionally characterize these macrophages, demonstrating that their differentiation enhances their ability to promote cyst cell proliferation. This observation indicates a model of reciprocal pathological interactions between cysts and the innate immune system: cyst epithelial cells promote macrophage polarization to a phenotype that, in turn, is especially efficient in promoting cyst cell proliferation and cyst growth. To better understand the genesis of this macrophage phenotype, we examined the role of IL-10, a regulatory cytokine shown to be important for macrophage-stimulated tissue repair in other settings. Herein, we show that the acquisition of the pathological macrophage phenotype requires IL-10 secretion by the macrophages. Further, we demonstrate a requirement for IL-10-dependent autocrine activation of the STAT3 pathway. These data suggest that the IL-10 pathway in macrophages plays an essential role in the pathological relationship between cysts and the innate immune system in PKD, and thus could be a potential therapeutic target. PMID:27491076

  3. Exploring the activated adipogenic niche: interactions of macrophages and adipocyte progenitors.

    PubMed

    Lee, Yun-Hee; Thacker, Robert I; Hall, Brian Eric; Kong, Raymond; Granneman, James G

    2014-01-01

    Adult adipose tissue contains a large supply of progenitors that can renew fat cells for homeostatic tissue maintenance and adaptive growth or regeneration in response to external challenges. However, the in vivo mechanisms that control adipocyte progenitor behavior are poorly characterized. We recently demonstrated that recruitment of adipocyte progenitors by macrophages is a central feature of adipose tissue remodeling under various adipogenic conditions. Catabolic remodeling of white adipose tissue by β3-adrenergic receptor stimulation requires anti-inflammatory M2-polarized macrophages to clear dying adipocytes and to recruit new brown adipocytes from progenitors. In this Extra Views article, we discuss in greater detail the cellular elements of adipogenic niches and report a strategy to isolate and characterize the subpopulations of macrophages and adipocyte progenitors that actively participate in adrenergic tissue remodeling. Further characterization of these subpopulations may facilitate identification of new cellular targets to improve metabolic and immune function of adipose tissue.

  4. Secreted Thrombospondin-1 Regulates Macrophage Interleukin-1β Production and Activation through CD47

    PubMed Central

    Stein, Erica V.; Miller, Thomas W.; Ivins-O’Keefe, Kelly; Kaur, Sukhbir; Roberts, David D.

    2016-01-01

    Thrombospondin-1 regulates inflammation by engaging several cell surface receptors and by modulating activities of other secreted factors. We have uncovered a novel role of thrombospondin-1 in modulating production and activation of the proinflammatory cytokine IL-1β by human and murine macrophages. Physiological concentrations of thrombospondin-1 limit the induction by lipopolysaccharide of IL-1β mRNA and total protein production by human macrophages. This inhibition can be explained by the ability of thrombospondin-1 to disrupt the interaction between CD47 and CD14, thereby limiting activation of NFκB/AP-1 by lipopolysaccharide. Only the CD47-binding domain of thrombospondin-1 exhibits this activity. In contrast, CD47, CD36, and integrin-binding domains of thrombospondin-1 independently enhance the inflammasome-dependent maturation of IL-1β in human THP-1 monocyte-derived macrophages. Correspondingly, mouse bone marrow-derived macrophages that lack either thrombospondin-1 or CD47 exhibit diminished induction of mature IL-1β in response to lipopolysaccharide. Lack of CD47 also limits lipopolysaccharide induction of IL-1β, NLRP3, and caspase-1 mRNAs. These data demonstrate that thrombospondin-1 exerts CD47-dependent and -independent pro-and anti-inflammatory effects on the IL-1β pathway. Therefore, thrombospondin-1 and its receptor CD47 may be useful targets for limiting the pro-inflammatory effects of lipopolysaccharide and for treating endotoxemia. PMID:26813769

  5. ARE MACROPHAGES ACTIVATED AND INDUCE PULMONARY INJURY BY INTRACELLULARLY BIOAVAILABLE IRON?

    EPA Science Inventory

    ARE MACROPHAGES ACTIVATED AND INDUCE PULMONARY INJURY BY INTRACELLULARLY BIOAVAILABLE IRON? UP Kodavanti1, MCJ Schladweiler1, S Becker2, DL Costa1, P Mayer3, A Ziesenis3, WG Kreyling3, 1ETD, 2HSDivision, NHEERL, USEPA, Research Triangle Park, NC, USA, and 3GSF, Inhalation Biology...

  6. Model-driven multi-omic data analysis elucidates metabolic immunomodulators of macrophage activation

    SciTech Connect

    Bordbar, Aarash; Mo, Monica L.; Nakayasu, Ernesto S.; Rutledge, Alexandra C.; Kim, Young-Mo; Metz, Thomas O.; Jones, Marcus B.; Frank, Bryan C.; Smith, Richard D.; Peterson, Scott N.; Hyduke, Daniel R.; Adkins, Joshua N.; Palsson, Bernhard O.

    2012-06-26

    Macrophages are central players in the immune response, manifesting divergent phenotypes to control inflammation and innate immunity through the release of cytokines and other regulatory factor-dependent signaling pathways. In recent years, the focus on metabolism has been reemphasized as critical signaling and regulatory pathways of human pathophysiology, ranging from cancer to aging, often converge on metabolic responses. Here, we used genome-scale modeling and multi-omics (transcriptomics, proteomics, and metabolomics) analysis to assess metabolic features critical for macrophage functions. We constructed a genome-scale metabolic network for the RAW 264.7 cell line to determine metabolic modulators of macrophage activation. Metabolites well-known to be associated with immunoactivation (e.g., glucose and arginine) and immunosuppression (e.g., tryptophan and vitamin D3) were amongst the most critical effectors. Intracellular metabolic mechanisms linked to critical suppressive effectors were then assessed, identifying a suppressive role for de novo nucleotide synthesis. Finally, the underlying metabolic mechanisms of macrophage activation are identified by analyzing multi-omic data obtained from LPS-stimulated RAW cells in the context of our flux-based predictions. Our study demonstrates metabolism's role in regulating activation may be greater than previously anticipated and elucidates underlying metabolic connections between activation and metabolic effectors.

  7. The interplay of the Notch signaling in hepatic stellate cells and macrophages determines the fate of liver fibrogenesis.

    PubMed

    Bansal, Ruchi; van Baarlen, Joop; Storm, Gert; Prakash, Jai

    2015-01-01

    Hepatic stellate cells (HSCs) known as "master producers" and macrophages as "master regulators", are the key cell types that strongly contribute to the progression of liver fibrosis. Since Notch signaling regulates multiple cellular processes, we aimed to study the role of Notch signaling in HSCs differentiation and macrophages polarization and to evaluate its implication in liver fibrogenesis. Notch pathway components were found to be significantly upregulated in TGFβ-activated HSCs, inflammatory M1 macrophages, and in mouse and human fibrotic livers. Interestingly, inhibition of Notch using a selective γ-secretase inhibitor, Avagacestat, significantly inhibited TGFβ-induced HSC activation and contractility, and suppressed M1 macrophages. Additionally, Avagacestat inhibited M1 driven-fibroblasts activation and fibroblasts-driven M1 polarization (nitric oxide release) in fibroblasts and macrophages co-culture, and conditioned medium studies. In vivo, post-disease treatment with Avagacestat significantly attenuated fibrogenesis in CCl4-induced liver fibrosis mouse model. These effects were attributed to the reduction in HSCs activation, and inhibition of inflammatory M1 macrophages and upregulation of suppressive M2 macrophages. These findings suggest that Notch signaling plays a crucial role in HSC activation and M1/M2 polarization of macrophages in liver fibrosis. These results provide new insights for the development of novel therapies against liver fibrosis through modulation of Notch signaling.

  8. The interplay of the Notch signaling in hepatic stellate cells and macrophages determines the fate of liver fibrogenesis

    PubMed Central

    Bansal, Ruchi; van Baarlen, Joop; Storm, Gert; Prakash, Jai

    2015-01-01

    Hepatic stellate cells (HSCs) known as “master producers” and macrophages as “master regulators”, are the key cell types that strongly contribute to the progression of liver fibrosis. Since Notch signaling regulates multiple cellular processes, we aimed to study the role of Notch signaling in HSCs differentiation and macrophages polarization and to evaluate its implication in liver fibrogenesis. Notch pathway components were found to be significantly upregulated in TGFβ-activated HSCs, inflammatory M1 macrophages, and in mouse and human fibrotic livers. Interestingly, inhibition of Notch using a selective γ-secretase inhibitor, Avagacestat, significantly inhibited TGFβ-induced HSC activation and contractility, and suppressed M1 macrophages. Additionally, Avagacestat inhibited M1 driven-fibroblasts activation and fibroblasts-driven M1 polarization (nitric oxide release) in fibroblasts and macrophages co-culture, and conditioned medium studies. In vivo, post-disease treatment with Avagacestat significantly attenuated fibrogenesis in CCl4-induced liver fibrosis mouse model. These effects were attributed to the reduction in HSCs activation, and inhibition of inflammatory M1 macrophages and upregulation of suppressive M2 macrophages. These findings suggest that Notch signaling plays a crucial role in HSC activation and M1/M2 polarization of macrophages in liver fibrosis. These results provide new insights for the development of novel therapies against liver fibrosis through modulation of Notch signaling. PMID:26658360

  9. Macrophage Activation in Pediatric Nonalcoholic Fatty Liver Disease (NAFLD) Correlates with Hepatic Progenitor Cell Response via Wnt3a Pathway

    PubMed Central

    Renzi, Anastasia; De Stefanis, Cristiano; Stronati, Laura; Franchitto, Antonio; Alisi, Anna; Onori, Paolo; De Vito, Rita; Alpini, Gianfranco; Gaudio, Eugenio

    2016-01-01

    Non-alcoholic fatty liver disease is one of the most important causes of liver-related morbidity in children. In non-alcoholic fatty liver disease, the activation of liver resident macrophage pool is a central event in the progression of liver injury. The aims of the present study were to evaluate the polarization of liver macrophages and the possible role of Wnt3a production by macrophages in hepatic progenitor cell response in the progression of pediatric non-alcoholic fatty liver disease. 32 children with biopsy-proven non-alcoholic fatty liver disease were included. 20 out of 32 patients were treated with docosahexaenoic acid for 18 months and biopsies at the baseline and after 18 months were included. Hepatic progenitor cell activation, macrophage subsets and Wnt/β-catenin pathway were evaluated by immunohistochemistry and immunofluorescence. Our result