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Sample records for activated macrophages aams

  1. 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

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

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

  3. Attenuated expression of interferon-β and interferon-λ1 by human alternatively activated macrophages.

    PubMed

    El Fiky, Ashraf; Perreault, Roger; McGinnis, Gwendolyn J; Rabin, Ronald L

    2013-12-01

    Macrophages can be polarized into classically (CAM) or alternatively (AAM) activated macrophages with IFN-γ or IL-4, respectively. CAM are associated with type 1 immune responses and are implicated in autoimmunity; AAM are associated with type 2 responses and are implicated in allergic diseases. An impediment in investigating macrophage biology using primary human monocyte derived macrophages is the wide inter-donor heterogeneity and the limited quantity of cells that survive in vitro polarization. To overcome this impediment, we established a protocol to generate CAM and AAM cultures derived from the THP-1 human promonocytic cell line. In this report, we demonstrate that THP-CAM and -AAM express gene and protein markers that define their primary human monocyte derived counterparts, such as IL-1β, CXCL10, and CXCL11 for CAM, and MRC1, IL-4 and CCL22 for AAM. In addition, we demonstrate that STAT6 is selectively activated in THP-AAM which, upon LPS stimulation, have an attenuated or delayed expression of IFN-β, IFN-λ1, and IFN α/β pathway genes compared to their CAM counterparts. Taken together, these findings may help further investigate human diseases associated with the alternatively activated macrophage phenotype using this reproducible in vitro macrophage model. PMID:23993990

  4. PPARγ-mediated increase in glucose availability sustains chronic Brucella abortus infection in alternatively activated macrophages

    PubMed Central

    Xavier, Mariana N.; Winter, Maria G.; Spees, Alanna M.; den Hartigh, Andreas B.; Nguyen, Kim; Roux, Christelle M.; Silva, Teane M. A.; Atluri, Vidya L.; Kerrinnes, Tobias; Keestra, A. Marijke; Monack, Denise M.; Luciw, Paul A.; Eigenheer, Richard A.; Bäumler, Andreas J.; Santos, Renato L.; Tsolis, Renée M.

    2013-01-01

    SUMMARY Eradication of persistent intracellular bacterial pathogens with antibiotic therapy is often slow or incomplete. However, strategies to augment antibiotics are hampered by our poor understanding of the nutritional environment that sustains chronic infection. Here we show that the intracellular pathogen Brucella abortus survives and replicates preferentially in alternatively activated macrophages (AAM), which are more abundant during chronic infection. A metabolic shift induced by peroxisome proliferator activated receptor γ (PPARγ), which increases intracellular glucose availability, is identified as a causal mechanism promoting enhanced bacterial survival in AAM. Glucose uptake was crucial for increased replication of B. abortus in AAM, and chronic infection, as inactivation of the bacterial glucose transporter gluP reduced both intracellular survival in AAM and persistence in mice. Thus, a shift in intracellular nutrient availability induced by PPARγ promotes chronic persistence of B. abortus within AAM and targeting this pathway may aid in eradicating chronic infection. PMID:23954155

  5. PPARγ-mediated increase in glucose availability sustains chronic Brucella abortus infection in alternatively activated macrophages.

    PubMed

    Xavier, Mariana N; Winter, Maria G; Spees, Alanna M; den Hartigh, Andreas B; Nguyen, Kim; Roux, Christelle M; Silva, Teane M A; Atluri, Vidya L; Kerrinnes, Tobias; Keestra, A Marijke; Monack, Denise M; Luciw, Paul A; Eigenheer, Richard A; Bäumler, Andreas J; Santos, Renato L; Tsolis, Renée M

    2013-08-14

    Eradication of persistent intracellular bacterial pathogens with antibiotic therapy is often slow or incomplete. However, strategies to augment antibiotics are hampered by our poor understanding of the nutritional environment that sustains chronic infection. Here we show that the intracellular pathogen Brucella abortus survives and replicates preferentially in alternatively activated macrophages (AAMs), which are more abundant during chronic infection. A metabolic shift induced by peroxisome proliferator-activated receptor γ (PPARγ), which increases intracellular glucose availability, is identified as a causal mechanism promoting enhanced bacterial survival in AAMs. Glucose uptake was crucial for increased replication of B. abortus in AAMs, and for chronic infection, as inactivation of the bacterial glucose transporter gluP reduced both intracellular survival in AAMs and persistence in mice. Thus, a shift in intracellular nutrient availability induced by PPARγ promotes chronic persistence of B. abortus within AAMs, and targeting this pathway may aid in eradicating chronic infection. PMID:23954155

  6. Differences in angiogenic potential of classically vs alternatively activated macrophages.

    PubMed

    Kodelja, V; Müller, C; Tenorio, S; Schebesch, C; Orfanos, C E; Goerdt, S

    1997-11-01

    Macrophages (M phi) are important for angiogenesis during inflammation, wound repair, and tumor growth. However, well-characterized M phi subsets such as IFN-gamma-induced, classically activated (ca) M phi or IL-4/glucocorticoid-induced, alternatively activated (aa) M phi have not been thoroughly examined for a positive or negative association with angiogenesis. While caM phi populate early inflammatory reactions and high-turnover granulomas, aaM phi occur in healing wounds and chronic inflammation. In contrast to caM phi-dominated lesions, aaM phi-rich lesions are highly vascularized. In order to determine their angiogenic potential in vitro, these M phi subsets as well as unstimulated control macrophages (coM phi) were analyzed by RT-PCR for mRNA expression of 10 angiogenic factors after 3 and 6 days of culture. Early during activation, caM phi and coM phi expressed equal levels of 8 of 10 angiogenic factors (PDGF-A, MK, TNF-alpha, TGF-beta 1, PDGF-B, HGF, TGF-alpha, IGF-1), while aaM phi showed expression of only 4 of these factors (TGF-beta 1, PDGF-B, HGF, GF-1). After maturation, TGF-alpha and IGF-1 showed a shift in mRNA expression from caM phi to aaM phi resulting in a considerably enhanced expression of these factors in day-6 aaM phi as compared to day-6 caM phi and coM phi while PDGF-A, MK, and TNF-alpha remained suppressed in day 6 aaM phi. In all M phi subsets including controls, mRNA expression of aFGF and bFGF was minimal or absent while TGFG-beta 1, HGF, and ODGF-B were constitutively expressed. In order to functionally integrate angiogenic factor mRNA expression profiles, mitogenic activity of M phi subsets towards microvascular endothelium was assessed by cocultivation. Coculture experiments revealed that endothelial proliferation induced by aaM phi was 3.0-3.5x higher than induced by caM phi. In conclusion, mature aaM phi are well equipped to play an important role in protracted M phi-associated angiogenic processes. Presumably due to expression of

  7. Alternatively activated macrophages are associated with metastasis and poor prognosis in prostate adenocarcinoma

    PubMed Central

    HU, WENXUE; QIAN, YUNJUAN; YU, FENG; LIU, WEI; WU, YANHUA; FANG, XIAOWU; HAO, WENKE

    2015-01-01

    Recent studies have revealed that alternatively activated macrophages (AAMs) are involved in tumor progression. However, the effect of AAMs on the metastasis of prostate cancer is poorly understood. In the present study, the prostate tissues of 42 patients with prostate adenocarcinoma (PCa) were used in the analysis of tumor associated macrophages (TAMs) and AAMs by immunofluorescence. The patients were followed up for 5 years. The associations of TAMs and AAMs with the clinicopathological features and outcome in these cases were evaluated. Immunofluorescent analysis indicated that the mean number of TAMs (CD68-positive cells) in the prostate tissues of PCa patients with metastasis [45.29±7.25 cells/high-power field (HPF)] was significantly higher compared with that of PCa patients without metastasis (33.57±5.25 cells/HPF; P<0.01). The mean numbers of AAMs (CD68- and CD206-positive cells) in the tissues of PCa patients with and without metastasis were 29.43±5.68 and 9.14±5.29 cells/HPF, respectively. In addition, the percentage of AAMs (number of AAMs/number of TAMs) was 65.11±9.68 and 27.32±7.85% in patients with and without metastasis, respectively. The differences in the number and percentage of AAMs between the two groups were statistically significant (P<0.01). The number and percentage of AAMs was positively correlated with tumor grade and serum prostate-specific antigen (PSA) level. Univariate analysis indicated that the level of PSA, Gleason score, metastatic status, T grade, number of TAMs, number of AAMs and percentage of AAMs were predictors of the overall survival. Furthermore, multivariate analyses revealed that Gleason score, level of PSA and number of TAMs were predictors for overall survival rate. These results indicate that TAMs and AAMs may be important in the metastasis of PCa, and that TAMs and AAMs may be used as potential biomarkers of poor prognosis in late-stage PCa patients. PMID:26622679

  8. Ly6Chigh Monocytes Become Alternatively Activated Macrophages in Schistosome Granulomas with Help from CD4+ Cells

    PubMed Central

    Girgis, Natasha M.; Gundra, Uma Mahesh; Ward, Lauren N.; Cabrera, Mynthia; Frevert, Ute; Loke, P'ng

    2014-01-01

    Alternatively activated macrophages (AAM) that accumulate during chronic T helper 2 inflammatory conditions may arise through proliferation of resident macrophages or recruitment of monocyte-derived cells. Liver granulomas that form around eggs of the helminth parasite Schistosoma mansoni require AAM to limit tissue damage. Here, we characterized monocyte and macrophage dynamics in the livers of infected CX3CR1GFP/+ mice. CX3CR1-GFP+ monocytes and macrophages accumulated around eggs and in granulomas during infection and upregulated PD-L2 expression, indicating differentiation into AAM. Intravital imaging of CX3CR1-GFP+ Ly6Clow monocytes revealed alterations in patrolling behavior including arrest around eggs that were not encased in granulomas. Differential labeling of CX3CR1-GFP+ cells in the blood and the tissue showed CD4+ T cell dependent accumulation of PD-L2+ CX3CR1-GFP+ AAM in the tissues as granulomas form. By adoptive transfer of Ly6Chigh and Ly6Clow monocytes into infected mice, we found that AAM originate primarily from transferred Ly6Chigh monocytes, but that these cells may transition through a Ly6Clow state and adopt patrolling behavior in the vasculature. Thus, during chronic helminth infection AAM can arise from recruited Ly6Chigh monocytes via help from CD4+ T cells. PMID:24967715

  9. Control of RSV-induced lung injury by alternatively activated macrophages is IL-4R alpha-, TLR4-, and IFN-beta-dependent.

    PubMed

    Shirey, K A; Pletneva, L M; Puche, A C; Keegan, A D; Prince, G A; Blanco, J C G; Vogel, S N

    2010-05-01

    Severe respiratory syncytial virus (RSV)-induced bronchiolitis has been associated with a mixed "Th1" and "Th2" cytokine storm. We hypothesized that differentiation of "alternatively activated" macrophages (AA-M phi) would mediate the resolution of RSV-induced lung injury. RSV induced interleukin (IL)-4 and IL-13 by murine lung and peritoneal macrophages, IL-4R alpha/STAT6-dependent AA-M phi differentiation, and significantly enhanced inflammation in the lungs of IL-4R alpha(-/-) mice. Adoptive transfer of wildtype macrophages to IL-4R alpha(-/-) mice restored RSV-inducible AA-M phi phenotype and diminished lung pathology. RSV-infected Toll-like receptor (TLR)4(-/-) and interferon (IFN)-beta(-/-) macrophages and mice also failed to express AA-M phi markers, but exhibited sustained proinflammatory cytokine production (e.g., IL-12) in vitro and in vivo and epithelial damage in vivo. TLR4 signaling is required for peroxisome proliferator-activated receptor gamma expression, a DNA-binding protein that induces AA-M phi genes, whereas IFN-beta regulates IL-4, IL-13, IL-4R alpha, and IL-10 expression in response to RSV. RSV-infected cotton rats treated with a cyclooxygenase-2 inhibitor increased expression of lung AA-M phi. These data suggest new treatment strategies for RSV that promote AA-M phi differentiation. PMID:20404812

  10. 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

  11. Enhanced allergic responsiveness after early childhood infection with respiratory viruses: Are long-lived alternatively activated macrophages the missing link?

    PubMed

    Keegan, Achsah D; Shirey, Kari Ann; Bagdure, Dayanand; Blanco, Jorge; Viscardi, Rose M; Vogel, Stefanie N

    2016-07-01

    Early childhood infection with respiratory viruses, including human rhinovirus, respiratory syncytial virus (RSV) and influenza, is associated with an increased risk of allergic asthma and severe exacerbation of ongoing disease. Despite the long recognition of this relationship, the mechanism linking viral infection and later susceptibility to allergic lung inflammation is still poorly understood. We discuss the literature and provide new evidence demonstrating that these viruses induce the alternative activation of macrophages. Alternatively activated macrophages (AAM) induced by RSV or influenza infection persisted in the lungs of mice up to 90 days after initial viral infection. Several studies suggest that AAM contribute to allergic inflammatory responses, although their mechanism of action is unclear. In this commentary, we propose that virus-induced AAM provide a link between viral infection and enhanced responses to inhaled allergens. PMID:27178560

  12. The adaptor protein insulin receptor substrate 2 inhibits alternative macrophage activation and allergic lung inflammation.

    PubMed

    Dasgupta, Preeta; Dorsey, Nicolas J; Li, Jiaqi; Qi, Xiulan; Smith, Elizabeth P; Yamaji-Kegan, Kazuyo; Keegan, Achsah D

    2016-01-01

    Insulin receptor substrate 2 (IRS2) is an adaptor protein that becomes tyrosine-phosphorylated in response to the cytokines interleukin-4 (IL-4) and IL-13, which results in activation of the phosphoinositide 3-kinase (PI3K)-Akt pathway. IL-4 and IL-13 contribute to allergic lung inflammation. To examine the role of IRS2 in allergic disease, we evaluated the responses of IRS2-deficient (IRS2(-/-)) mice. Unexpectedly, loss of IRS2 resulted in a substantial increase in the expression of a subset of genes associated with the generation of alternatively activated macrophages (AAMs) in response to IL-4 or IL-13 in vitro. AAMs secrete factors that enhance allergic responses and promote airway remodeling. Moreover, compared to IRS2(+/+) mice, IRS2(+/-) and IRS2(-/-) mice developed enhanced pulmonary inflammation, accumulated eosinophils and AAMs, and exhibited airway and vascular remodeling upon allergen stimulation, responses that partially depended on macrophage-intrinsic IRS2 signaling. Both in unstimulated and IL-4-stimulated macrophages, lack of IRS2 enhanced phosphorylation of Akt and ribosomal S6 protein. Thus, we identified a critical inhibitory loop downstream of IRS2, demonstrating an unanticipated and previously unrecognized role for IRS2 in suppressing allergic lung inflammation and remodeling. PMID:27330190

  13. Phosphatase regulation of macrophage activation.

    PubMed

    Kozicky, Lisa K; Sly, Laura M

    2015-08-01

    Macrophages are innate immune cells that play critical roles in tissue homeostasis and the immune response to invading pathogens or tumor cells. A hallmark of macrophages is their "plasticity," that is, their ability to respond to cues in their local microenvironment and adapt their activation state or phenotype to mount an appropriate response. During the inflammatory response, macrophages may be required to mount a profound anti-bacterial or anti-tumor response, an anti-inflammatory response, an anti-parasitic response, or a wound healing response. To do so, macrophages express cell surface receptors for growth factors, chemokines and cytokines, as well pathogen and danger associated molecular patterns. Downstream of these cell surface receptors, cell signalling cascades are activated and deactivated by reversible and competing activities of lipid and protein kinases and phosphatases. While kinases drive the activation of cell signalling pathways critical for macrophage activation, the strength and duration of the signalling is regulated by phosphatases. Hence, gene knockout mouse models have revealed critical roles for lipid and protein phosphatases in macrophage activation. Herein, we describe our current understanding and the key roles of specific cellular phosphatases in the regulation of the quality of macrophage polarization as well as the quantity of cytokines produced by activated macrophages. PMID:26216598

  14. 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

  15. MSSA of globally gridded AAM

    NASA Astrophysics Data System (ADS)

    Zotov, Leonid; Schindelegger, Michael; Bizouard, Christian

    2016-04-01

    Multichannel singular spectrum analysis (MSSA) was applied to 111 years of Atmospheric Angular Momentum (AAM) grid data from ECMWMF 20th Century Reanalysis (ERA-20C) model. Components of zonal atmospheric circulation influencing Length of Day (LOD) were separated. Some of them are related to El Nino Southern Oscillation (ENSO) global circulation modes, others represent possible trends. Meridional AAM components were processed by complex MSSA. Annual, semiannual components were separated. The maps of influence in the Chandler and annual bands on Polar Motion (PM) were obtained. The regions where the torques come from, influence of friction in the mountains was also analyzed.

  16. 200 North Aggregate Area source AAMS report

    SciTech Connect

    Not Available

    1993-06-01

    This report presents the results of an aggregate area management study (AAMS) for the 200 North Aggregate Area in the 200 Areas of the US Department of Energy (DOE) Hanford Site in Washington State. This scoping level study provides the basis for initiating Remedial Investigation/Feasibility Study (RI/FS) activities under the Comprehensive Environmental Response, Compensation, and Liability Act of 1980 (CERCLA) or Resource Conservation and Recovery Act (RCRA) Facility Investigations (RFI) and Corrective Measures Studies (CMS) under RCRA. This report also integrates select RCRA treatment, storage, or disposal (TSD) closure activities with CERCLA and RCRA past practice investigations.

  17. Storage xyloglucans: potent macrophages activators.

    PubMed

    do Rosário, Marianna Maia Taulois; Kangussu-Marcolino, Mônica Mendes; do Amaral, Alex Evangelista; Noleto, Guilhermina Rodrigues; Petkowicz, Carmen Lúcia de Oliveira

    2011-01-15

    Storage xyloglucans from the seeds of Copaifera langsdorffii, Hymenaea courbaril and Tamarindus indica were obtained by aqueous extraction from the milled and defatted cotyledons, XGC, XGJ and XGT, respectively. The resulting fractions showed similar monosaccharide composition with Glc:Xyl:Gal molar ratios of 2.4:1.5:1.0, 3.8:1.5:1,0 and 3.6:2.4:1.0 for XGC, XGJ and XGT, respectively. High-performance size-exclusion chromatography of the polysaccharides showed unimodal profiles, and the average molar mass (M(w)) was obtained for XGC (9.6 × 10⁵ g/mol), XGJ (9.1 × 10⁵ g/mol) and XGT (7.3 × 10⁵ g/mol). The immunomodulatory effects of the xyloglucans on peritoneal macrophages were evaluated. Phagocytic activity was observed in macrophages treated with XGT. The effect of XGT was tested on the production of O₂(.-) and NO. At 25 μg/ml XGT caused a 100% increase in NO production when compared to the control group; however, it did not affect O₂(.-) production in the absence of PMA. The production of TNF-α, interleukins 1β and 6 by macrophages in the presence of the xyloglucans was evaluated. The polysaccharides affected the production of the cytokines by macrophages to different degrees. XGC caused an enhancement of IL-1β and TNF-α production, compared to the other xyloglucans. For IL-6 production, XGT gave greater stimulation than XGC and XGJ, reaching 87% at 50 μg/ml. XGJ promoted a statistically significant effect on all cytokine productions tested. The results indicate that the xyloglucans from C. langsdorffii, H. courbaril and T. indica can be classified as biological response modifiers (BRM). PMID:20888807

  18. Netrin-1 attenuates cardiac ischemia reperfusion injury and generates alternatively activated macrophages.

    PubMed

    Mao, Xiaogang; Xing, Hui; Mao, Aihua; Jiang, Hong; Cheng, Li; Liu, Yun; Quan, Xiaozhen; Li, Lin

    2014-04-01

    Ischemia reperfusion (IR) injury is a major issue in cardiac transplantation and inflammatory processes play a major role in myocardial IR injury. Netrin-1 is a laminin-related protein identified as a neuronal guidance cue and netrin-1 expressed outside the nervous system inhibits migration of leukocytes in vitro and in vivo and attenuates inflammation-mediated tissue injury. In our study, hearts of C57BL/6 mice were flushed and stored in cold Bretschneider solution for 8 h and then transplanted into syngeneic recipient. We found that netrin-1 decreased cardiomyocyte apoptosis and recruitment of neutrophils and macrophages. Troponin T (TnT) production on 24 h after myocardial IR injury was reduced by netrin-1 administration. Cardiac output at 60 mmHg of afterload pressure was significantly increased in hearts with netrin-1 administration (IR + Netrin-1: 59.9 ± 5.78 ml/min; IR: 26.2 ± 4.3 ml/min; P < 0.05). Netrin-1 treatment increased expression of the alternatively activated macrophage (AAM) markers arginase-1 (Arg-1) and mannose receptor (MR) and promoted proliferator-activated receptor γ (PPARγ) expression in cardiac allograft. Furthermore, decreased TnT expression and reduced allograft infiltration of neutrophils and monocytes/macrophages by netrin-1 was abolished with addition of PPARγ antagonist. In conclusion, netrin-1 attenuates cardiac IR injury and generates AAM which contributes to the protective effect of netrin-1. PMID:24234226

  19. Effect of hydroxyapatite microcrystals on macrophage activity.

    PubMed

    Fukuchi, N; Akao, M; Sato, A

    1995-01-01

    Hydroxyapatite (HAp) microcrystals were synthesized by a neutralization reaction of Ca(OH)2 suspension and H3PO4 solution using an ultrasonic homogenizer. The in vitro interaction of HAp microcrystals with rat peritoneal macrophages was investigated by measuring the viability, acid phosphatase (ACP) activity, lactate dehydrogenase (LDH) activity and intracellular calcium content. HAp calcined at 800 degrees C and alpha-alumina particles (alumina) were used as comparative materials. Macrophages actively phagocytosed HAp microcrystals by dissolving them. However, no damage in macrophages exposed to HAp microcrystals was observed by transmission electron microscopy. Macrophages in the presence of HAp microcrystals showed less ACP and LDH activity and higher intracellular calcium content than those in the presence of calcined HAp and alumina. HAp microcrystals had excellent biocompatibility to macrophages as well as sintered HAp. PMID:8785507

  20. Macrophage activation by OM-85 BV.

    PubMed

    Mauël, J

    1992-01-01

    Peritoneal or bone-marrow-derived murine macrophages were exposed for 24 h in vitro to dilutions of the bacterial extract OM-85 BV, in the presence or absence of other added compounds [macrophage-activating factor (MAF), recombinant murine interferon-gamma (IFN-gamma)]. Various metabolic responses and functional activities were then measured. Glucose oxidation through the hexose monophosphate shunt pathway was markedly stimulated in OM-85 BV-treated macrophages compared to control macrophages. Similarly, OM-85 BV primed macrophages for superoxide production upon triggering by phorbol myristate acetate. Both effects were further enhanced by simultaneous treatment of the cells with MAF with OM-85 BV. The bacterial extract also induced macrophages to release large amounts of nitrite (a marker of the activated state). As regards functional responses, coincubation with MAF and OM-85 BV activated macrophages to destroy target cells as well as intracellular microorganisms; in the latter case, similar results were obtained when MAF was replaced by IFN-gamma. In all these tests, the possibility that the observed effects were due to contamination of the bacterial extracts by endotoxin could be excluded. The above results indicate that OM-85 BV induces metabolic and functional properties in macrophages that are characteristic of the activated state and are important for host defence. PMID:1332156

  1. The Metabolic Prospective and Redox Regulation of Macrophage Polarization

    PubMed Central

    He, Chao; Carter, A Brent

    2016-01-01

    Macrophage plasticity is an important feature of these innate immune cells. Macrophage phenotypes are divided into two categories, the classically activated macrophages (CAM, M1 phenotype) and the alternatively activated macrophages (AAM, M2 phenotype). M1 macrophages are commonly associated with the generation of proinflammatory cytokines, whereas M2 macrophages are anti-inflammatory and often associated with tumor progression and fibrosis development. Macrophages produce high levels of reactive oxygen species (ROS). Recent evidence suggests ROS can potentially regulate macrophage phenotype. In addition, macrophages phenotypes are closely related to their metabolic patterns, particularly fatty acid/cholesterol metabolism. In this review, we briefly summarize recent advances in macrophage polarization with special attention to their relevance to specific disease conditions and metabolic regulation of polarization. Understanding these metabolic switches can facilitate the development of targeted therapies for various diseases. PMID:26962470

  2. 76 FR 21035 - Colfor Manufacturing, Inc., an AAM Company, Minerva, OH; Colfor Manufacturing, Inc., an AAM...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-04-14

    ... Employment and Training Administration Colfor Manufacturing, Inc., an AAM Company, Minerva, OH; Colfor Manufacturing, Inc., an AAM Company, Salem, OH; Amended Certification Regarding Eligibility To Apply for Worker... Assistance on March 17, 2010, applicable to workers of Colfor Manufacturing, Inc., Minerva, Ohio. The...

  3. The Many Alternative Faces of Macrophage Activation.

    PubMed

    Hume, David A

    2015-01-01

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

  4. E-cadherin expression in macrophages dampens their inflammatory responsiveness in vitro, but does not modulate M2-regulated pathologies in vivo

    PubMed Central

    Van den Bossche, Jan; Laoui, Damya; Naessens, Thomas; Smits, Hermelijn H.; Hokke, Cornelis H.; Stijlemans, Benoît; Grooten, Johan; De Baetselier, Patrick; Van Ginderachter, Jo A.

    2015-01-01

    IL-4/IL-13-induced alternatively activated macrophages (M(IL-4/IL-13), AAMs or M2) are known to express E-cadherin, enabling them to engage in heterotypic cellular interactions and IL-4-driven macrophage fusion in vitro. Here we show that E-cadherin overexpression in Raw 264.7 macrophages inhibits their inflammatory response to LPS stimulation, as demonstrated by a reduced secretion of inflammatory mediators like interleukin (IL)-6, tumor necrosis factor (TNF) and nitric oxide (NO). To study the function of E-cadherin in M(IL-4/IL-13) macrophages in vivo, we generated macrophage-specific E-cadherin-deficient C57BL/6 mice. Using this new tool, we analyzed immunological parameters during two typical AAM-associated Th2-driven diseases and assessed Th2-associated granuloma formation. Although E-cadherin is strongly induced in AAMs during Taenia crassiceps helminth infections and allergic airway inflammation, its deletion in macrophages does not affect the course of both Th2 cytokine-driven diseases. Moreover, macrophage E-cadherin expression is largely redundant for granuloma formation around Schistosoma mansoni ova. Overall, we conclude that E-cadherin is a valuable AAM marker which suppresses the inflammatory response when overexpressed. Yet E-cadherin deletion in macrophages does not affect M(LPS+IFNγ) and M(IL-4) polarization in vitro, nor in vivo macrophage function, at least in the conditions tested. PMID:26226941

  5. 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

  6. Selenoprotein Expression in Macrophages Is Critical for Optimal Clearance of Parasitic Helminth Nippostrongylus brasiliensis.

    PubMed

    Nelson, Shakira M; Shay, Ashley E; James, Jamaal L; Carlson, Bradley A; Urban, Joseph F; Prabhu, K Sandeep

    2016-02-01

    The plasticity of macrophages is evident in helminthic parasite infections, providing protection from inflammation. Previously we demonstrated that the micronutrient selenium induces a phenotypic switch in macrophage activation from a classically activated (pro-inflammatory; M1/CAM) toward an alternatively activated (anti-inflammatory; M2/AAM) phenotype, where cyclooxygenase (COX)-dependent cyclopentenone prostaglandin J2 (15d-PGJ2) plays a key role. Here, we hypothesize that dietary selenium modulates macrophage polarization toward an AAM phenotype to assist in the increasing clearance of adult Nippostrongylus brasiliensis, a gastrointestinal nematode parasite. Mice on a selenium-adequate (0.08 ppm) diet significantly augmented intestinal AAM presence while decreasing adult worms and fecal egg production when compared with infection of mice on selenium-deficient (<0.01 ppm) diet. Further increase in dietary selenium to supraphysiological levels (0.4 ppm) had very little or no impact on worm expulsion. Normal adult worm clearance and enhanced AAM marker expression were observed in the selenium-supplemented Trsp(fl/fl)Cre(WT) mice that express selenoproteins driven by tRNA(Sec) (Trsp), whereas N. brasiliensis-infected Trsp(fl/fl)Cre(LysM) selenium-supplemented mice showed a decreased clearance, with lowered intestinal expression of several AAM markers. Inhibition of the COX pathway with indomethacin resulted in delayed worm expulsion in selenium-adequate mice. This was rescued with 15d-PGJ2, which partially recapitulated the effect of selenium supplementation on fecal egg output in addition to increasing markers of AAMs in the small intestine. Antagonism of PPARγ blocked the effect of selenium. These results suggest that optimal expression of selenoproteins and selenium-dependent production of COX-derived endogenous prostanoids, such as Δ(12)-PGJ2 and 15d-PGJ2, may regulate AAM activation to enhance anti-helminthic parasite responses. PMID:26644468

  7. The interaction of human macrophage subsets with silicone as a biomaterial.

    PubMed

    Vijaya Bhaskar, Thanga Bhuvanesh; Ma, Nan; Lendlein, Andreas; Roch, Toralf

    2015-01-01

    Silicones are widely used as biomaterials for medical devices such as extracorporeal equipments. However, there is often conflicting evidence about their supposed cell- and histocompatibility. Macrophages could mediate silicone-induced adverse responses such as foreign body reaction and fibrous encapsulation. The polarization behaviour of macrophages could determine the clinical outcome after implantation of biomaterials. Induction of classically activated macrophages (CAM) may induce and support uncontrolled inflammatory responses and undesired material degradation. In contrast, polarization into alternatively activated macrophages (AAM) is assumed to support healing processes and implant integration.This study compared the interaction of non-polarized macrophages (M0), CAM, and AAM with commercially available tissue culture polystyrene (TCP) and a medical grade silicone-based biomaterial, regarding the secretion of inflammatory mediators such as cytokines and chemokines. Firstly, by using the Limulus amoebocyte lysate (LAL) test the silicone films were shown to be free of soluble endotoxins, which is the prerequisite to investigate their interaction with primary immune cells. Primary human monocyte-derived macrophages (M0) were polarized into CAM and AAM by addition of suitable differentiation factors. These macrophage subsets were incubated on the materials for 24 hours and their viability and cytokine secretion was assessed. In comparison to TCP, cell adhesion was lower on silicone after 24 hours for all three macrophage subsets. However, compared to TCP, silicone induced higher levels of certain inflammatory and chemotactic cytokines in M0, CAM, and AAM macrophage subsets.Conclusively, it was shown that silicone has the ability to induce a pro-inflammatory state to different magnitudes dependent on the macrophage subsets. This priming of the macrophage phenotype by silicone could explain the incidence of severe foreign body complications observed in vivo. PMID

  8. Different pathways of macrophage activation and polarization.

    PubMed

    Juhas, Ulana; Ryba-Stanisławowska, Monika; Szargiej, Patryk; Myśliwska, Jolanta

    2015-01-01

    Monocytes are short-lived cells and undergo spontaneous apoptosis every day. Inflammatory responses may induce dramatic up-regulation of monocyte survival and differentiation. When monocytes are recruited to an area of infection they may differentiate into macrophages. In different microenvironments macrophages polarize into two types. The M1 or classically activated macrophages are characterized by the high ability to produce pro-inflammatory cytokines and the production of NO through the induced synthesis of iNOS. The M2 or alternatively activated macrophages are divided into 3 subtypes, M2 a, b and c, and they have anti-inflammatory properties. Mediators of M1 macrophage TLR-dependent polarization include transcription factors such as NF-κB, AP-1, PU.1, CCAAT/enhancer-binding protein α (C/EBP-α), STAT1 as well as interferon regulatory factor 5 (IRF5), while the transcription factors which promote M2 activation include IRF4, C/EBP-β, Krüppel-like factor 4 (KLF4), STAT6 and PPARγ receptor. PMID:25983288

  9. Crocodylus siamensis serum and macrophage phagocytic activity.

    PubMed

    Aree, Kalaya; Siruntawineti, Jindawan; Chaeychomsri, Win

    2011-12-01

    Antimicrobial activity of sera from many crocodilian species has been recognized. This activity was proposed to be mediated, at least in part, by complement. Due to the fact that complement proteins have different functions in the immune system, they may be involved in phagocytic process of phagocytes. In the present study, the effects of Siamese crocodile serum on phagocytic activity of macrophages as well as the possible involvement of complement in this process were examined. The results showed increases in the phagocytosis of both Escherichia coli and to a lesser extent, Staphylococcus aureus upon incubation of murine macrophage cell line with fresh crocodile serum (FS). Similar to FS, other crocodile blood products, including freeze dried serum (DS) and freeze dried whole blood (DWB) exhibited phagocytosis-enhancing property. However the ability of DWB to enhance phagocytosis was less efficient than that of FS and DS, suggesting that serum factors were involved in this process. Treatment of FS with heat at 56 degrees C for 30 min deteriorated the effect of FS on bacterial uptake of macrophages, suggesting that complement proteins play a role in the modulation of the phagocytic process. Collectively, the results of the present study suggested that crocodile serum enhances the macrophage phagocytic activity through complement activity and, therefore, may be taken as an alternative medicine for supporting the human immune responses. PMID:22619919

  10. PROTEASOME ACTIVITY DECLINES IN AGED MACROPHAGES

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The ubiquitin-proteasome pathway is involved in regulation of a variety of biologically important processes including antigen presentation by macrophages. Age-related decrease in proteasome activity has been reported in other tissues. However, the effect of aging on the ubiquitin-proteasome pathway ...

  11. PROTEASOME ACTIVITY DECLINES IN AGED MACROPHAGES

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The ubiquitin-proteasome pathway is involved in regulation of a variety of biologically important processes including antigen presentation by macrophages (Mf). Age-related decrease in proteasome activity has been reported in other tissues. However, the effect of aging on the ubiquitin-proteasome pat...

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

    PubMed Central

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

    2015-01-01

    Macrophages are divided into two subpopulations: classically activated macrophages (M1) and alternatively activated macrophages (M2). BCG (Bacilli Calmette-Guérin) activates disabled naïve 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-α), Interleukin 6 (IL-6), Interleukin 12 (IL-12), Monocyte chemoattractant protein-1 (MCP-1) and Interleukin-1 beta (IL-1β), 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-β) 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. PMID:26429502

  13. MACROPHAGE ACTIVATION SYNDROME AND CYTOKINE DIRECTED THERAPIES

    PubMed Central

    Grom, Alexei A.

    2014-01-01

    Macrophage activation syndrome (MAS) is an episode of overwhelming inflammation that occurs most commonly in children with systemic juvenile idiopathic arthritis. It is characterized by expansion and activation of T lymphocytes and hemophagocytic macrophages, and bears great similarity to hemophagocytic lymphohistiocytosis (HLH). This disorder has substantial morbidity and mortality, and there is frequently a delay in recognition and initiation of treatment. Here, we will review what is known about the pathogenesis of MAS and in particular its similarities to HLH. The development of MAS is characterized by a cytokine storm, with the elaboration of numerous proinflammatory cytokines. We will examine the evidence for various cytokines in the initiation and pathogenesis of MAS, and discuss how new biologic therapies may alter the risk of MAS. Finally we will review current treatment options for MAS, and examine how cytokine-directed therapy could serve as novel treatment modalities. PMID:24974063

  14. Macrophage activation syndrome in autoimmune disease.

    PubMed

    Deane, Sean; Selmi, Carlo; Teuber, Suzanne S; Gershwin, M Eric

    2010-01-01

    Macrophage activation syndrome (MAS) is a phenomenon characterized by cytopenia, organ dysfunction, and coagulopathy associated with an inappropriate activation of macrophages. Current diagnostic criteria are imprecise, but the syndrome is now recognized as a form of hemophagocytic lymphohistiocytosis that is characteristically associated with autoimmune diatheses. The diagnosis of incipient MAS in patients with autoimmune disease requires a high index of suspicion, as several characteristics of the disorder may be present in the underlying condition or infectious complications associated with the treatment thereof. Proposed treatment regimens include aggressive approaches that require validation in future controlled studies. This review discusses the major aspects of the pathophysiology, diagnosis, and management of MAS with a focus on the association with autoimmune disease. PMID:20407267

  15. Macrophage activation and polarization: nomenclature and experimental guidelines.

    PubMed

    Murray, Peter J; Allen, Judith E; Biswas, Subhra K; Fisher, Edward A; Gilroy, Derek W; Goerdt, Sergij; Gordon, Siamon; Hamilton, John A; Ivashkiv, Lionel B; Lawrence, Toby; Locati, Massimo; Mantovani, Alberto; Martinez, Fernando O; Mege, Jean-Louis; Mosser, David M; Natoli, Gioacchino; Saeij, Jeroen P; Schultze, Joachim L; Shirey, Kari Ann; Sica, Antonio; Suttles, Jill; Udalova, Irina; van Ginderachter, Jo A; Vogel, Stefanie N; Wynn, Thomas A

    2014-07-17

    Description of macrophage activation is currently contentious and confusing. Like the biblical Tower of Babel, macrophage activation encompasses a panoply of descriptors used in different ways. The lack of consensus on how to define macrophage activation in experiments in vitro and in vivo impedes progress in multiple ways, including the fact that many researchers still consider there to be only two types of activated macrophages, often termed M1 and M2. Here, we describe a set of standards encompassing three principles-the source of macrophages, definition of the activators, and a consensus collection of markers to describe macrophage activation-with the goal of unifying experimental standards for diverse experimental scenarios. Collectively, we propose a common framework for macrophage-activation nomenclature. PMID:25035950

  16. 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.

  17. 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.

  18. Macrophage activation and induction of macrophage cytotoxicity by purified polysaccharide fractions from the plant Echinacea purpurea.

    PubMed Central

    Stimpel, M; Proksch, A; Wagner, H; Lohmann-Matthes, M L

    1984-01-01

    Purified polysaccharides (EPS) prepared from the plant Echinacea purpurea are shown to strongly activate macrophages. Macrophages activated with these substances develop pronounced extracellular cytotoxicity against tumor targets. The activation is brought about by EPS alone and is independent of any cooperative effect with lymphocytes. Also the production and secretion of oxygen radicals and interleukin 1 by macrophages is increased after activation with EPS. Cells of the macrophages lineage seem to be the main target for the action of these polysaccharides. EPS has no effect on T lymphocytes. B lymphocytes show a comparatively modest proliferation after incubation with E. purpurea EPS. Thus, these compounds, which are at least in tissue culture completely nontoxic, may be suited to activate in vivo cells of the macrophage system to cytotoxicity. They may therefore be of relevance in tumor and infectious systems. PMID:6389368

  19. [The biological activity of macrophages in health and disease].

    PubMed

    Nazimek, Katarzyna; Bryniarski, Krzysztof

    2012-01-01

    Macrophages are involved in immune response as phagocytes, antigen presenting cells and as effector cells of delayed-type hypersensitivity. Moreover, the activity of macrophages is associated with modulation of many biological processes during the whole life and depends on the actual macrophage phenotype induced under the influence of various microenvironmental stimuli. In pregnancy, placental macrophages induce the development of maternal tolerance to fetal antigens, while fetal macrophages are responsible for proper formation of tissues and organs. Residual macrophages play a very important role in tissue homeostasis, apoptotic cell clearance to prevent autoimmunization and first defense in infections. The inflammatory response of macrophages may be modulated by pathogens. Their suppressive activity is observed in immunologically privileged organs such as testes. In pathologies, macrophages are responsible for tissue damage in a case of nonspecific activation followed by overproduction of proinflammatory factors. Suppression of a specific immune response against tumors is mainly the effect of tumor associated macrophage (TAM) action. On the other hand, presentation of allergens or self-antigens by macrophages and their nonspecific activation by necrotic adipocytes leads to the induction of a chronic inflammatory response and impairment of immunity. Therefore, modulation of macrophage functions may be the key for improvement of therapy of cancer and allergic, autoimmune, metabolic, cardiovascular and Alzheimer's diseases. PMID:22922151

  20. 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

  1. Myelin alters the inflammatory phenotype of macrophages by activating PPARs

    PubMed Central

    2013-01-01

    Background Foamy macrophages, containing myelin degradation products, are abundantly found in active multiple sclerosis (MS) lesions. Recent studies have described an altered phenotype of macrophages after myelin internalization. However, mechanisms by which myelin affects the phenotype of macrophages and how this phenotype influences lesion progression remain unclear. Results We demonstrate that myelin as well as phosphatidylserine (PS), a phospholipid found in myelin, reduce nitric oxide production by macrophages through activation of peroxisome proliferator-activated receptor β/δ (PPARβ/δ). Furthermore, uptake of PS by macrophages, after intravenous injection of PS-containing liposomes (PSLs), suppresses the production of inflammatory mediators and ameliorates experimental autoimmune encephalomyelitis (EAE), an animal model of MS. The protective effect of PSLs in EAE animals is associated with a reduced immune cell infiltration into the central nervous system and decreased splenic cognate antigen specific proliferation. Interestingly, PPARβ/δ is activated in foamy macrophages in active MS lesions, indicating that myelin also activates PPARβ/δ in macrophages in the human brain. Conclusion Our data show that myelin modulates the phenotype of macrophages by PPAR activation, which may subsequently dampen MS lesion progression. Moreover, our results suggest that myelin-derived PS mediates PPARβ/δ activation in macrophages after myelin uptake. The immunoregulatory impact of naturally-occurring myelin lipids may hold promise for future MS therapeutics. PMID:24252308

  2. Reversible adsorption of catalase onto Fe(3+) chelated poly(AAm-GMA)-IDA cryogels.

    PubMed

    Aktaş Uygun, Deniz; Uygun, Murat; Akgöl, Sinan; Denizli, Adil

    2015-05-01

    In this presented study, poly(acrylamide-glycidyl methacrylate) [poly(AAm-GMA)] cryogels were synthesized by cryopolymerization technique at sub-zero temperature. Prepared cryogels were then functionalized with iminodiacetic acid (IDA) and chelated with Fe(3+) ions in order produce the metal chelate affinity matrix. Synthesized cryogels were characterized with FTIR, ESEM and EDX analysis, and it was found that the cryogel had sponge like structure with interconnected pores and their pore diameter was about 200 μm. Fe(3+) chelated poly(AAm-GMA)-IDA cryogels were used for the adsorption of catalase and optimum adsorption conditions were determined by varying the medium pH, initial catalase concentration, temperature and ionic strength. Maximum catalase adsorption onto Fe(3+) chelated poly(AAm-GMA)-IDA cryogel was found to be 12.99 mg/g cryogel at 25 °C, by using pH 5.0 acetate buffer. Adsorbed catalase was removed from the cryogel by using 1.0M of NaCl solution and desorption yield was found to be 96%. Additionally, reusability profile of the Fe(3+) chelated poly(AAm-GMA)-IDA cryogel was also investigated and it was found that, adsorption capacity of the cryogels didn't decrease significantly at the end of the 40 reuses. Catalase activity studies were also tested and it was demonstrated that desorbed catalase retained 70% of its initial activity. PMID:25746283

  3. 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

  4. 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. PMID:26631474

  5. 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

  6. Effect of lectins on mouse peritoneal macrophage phagocytic activity.

    PubMed

    Maldonado, G; Porras, F; Fernández, L; Vázquez, L; Zenteno, E

    1994-11-01

    We studied the in vitro ability of lectin-treated murine peritoneal macrophages to attach and phagocytize particulate antigens. Glucose and mannose specific lectins such as Con-A and lentil lectin, as well as complex lactosamine residues specific lectins, such as Phaseolus vulgaris var. cacahuate and Phaseolus coccineus var. alubia, increased the macrophage phagocytic activity towards heterologous erythrocytes, whereas peanut agglutinin, a galactose-specific lectin, diminished the macrophage phagocytic activity. These results suggest that a galactose-N-acetyl-D galactosamine-containing structure could participate as negative modulator of the phagocytic activity. PMID:7851961

  7. 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.

  8. 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.

  9. Salicylate improves macrophage cholesterol homeostasis via activation of Ampk.

    PubMed

    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

    2015-05-01

    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

  10. 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

  11. The transcription factor PU.1 promotes alternative macrophage polarization and asthmatic airway inflammation.

    PubMed

    Qian, Feng; Deng, Jing; Lee, Yong Gyu; Zhu, Jimmy; Karpurapu, Manjula; Chung, Sangwoon; Zheng, Jun-Nian; Xiao, Lei; Park, Gye Young; Christman, John W

    2015-12-01

    The transcription factor PU.1 is involved in regulation of macrophage differentiation and maturation. However, the role of PU.1 in alternatively activated macrophage (AAM) and asthmatic inflammation has yet been investigated. Here we report that PU.1 serves as a critical regulator of AAM polarization and promotes the pathological progress of asthmatic airway inflammation. In response to the challenge of DRA (dust mite, ragweed, and Aspergillus) allergens, conditional PU.1-deficient (PU/ER(T)(+/-)) mice displayed attenuated allergic airway inflammation, including decreased alveolar eosinophil infiltration and reduced production of IgE, which were associated with decreased mucous glands and goblet cell hyperplasia. The reduced asthmatic inflammation in PU/ER(T)(+/-) mice was restored by adoptive transfer of IL-4-induced wild-type (WT) macrophages. Moreover, after treating PU/ER(T)(+/-) mice with tamoxifen to rescue PU.1 function, the allergic asthmatic inflammation was significantly restored. In vitro studies demonstrate that treatment of PU.1-deficient macrophages with IL-4 attenuated the expression of chitinase 3-like 3 (Ym-1) and resistin-like molecule alpha 1 (Fizz-1), two specific markers of AAM polarization. In addition, PU.1 expression in macrophages was inducible in response to IL-4 challenge, which was associated with phosphorylation of signal transducer and activator of transcription 6 (STAT6). Furthermore, DRA challenge in sensitized mice almost abrogated gene expression of Ym-1 and Fizz-1 in lung tissues of PU/ER(T)(+/-) mice compared with WT mice. These data, all together, indicate that PU.1 plays a critical role in AAM polarization and asthmatic inflammation. PMID:26101328

  12. Jacalin-Activated Macrophages Exhibit an Antitumor Phenotype

    PubMed Central

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

    2016-01-01

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

  13. Jacalin-Activated Macrophages Exhibit an Antitumor Phenotype.

    PubMed

    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

  14. Ginger extract inhibits LPS induced macrophage activation and function

    PubMed Central

    2008-01-01

    Background Macrophages play a dual role in host defence. They act as the first line of defence by mounting an inflammatory response to antigen exposure and also act as antigen presenting cells and initiate the adaptive immune response. They are also the primary infiltrating cells at the site of inflammation. Inhibition of macrophage activation is one of the possible approaches towards modulating inflammation. Both conventional and alternative approaches are being studied in this regard. Ginger, an herbal product with broad anti inflammatory actions, is used as an alternative medicine in a number of inflammatory conditions like rheumatic disorders. In the present study we examined the effect of ginger extract on macrophage activation in the presence of LPS stimulation. Methods Murine peritoneal macrophages were stimulated by LPS in presence or absence of ginger extract and production of proinflammatory cytokines and chemokines were observed. We also studied the effect of ginger extract on the LPS induced expression of MHC II, B7.1, B7.2 and CD40 molecules. We also studied the antigen presenting function of ginger extract treated macrophages by primary mixed lymphocyte reaction. Results We observed that ginger extract inhibited IL-12, TNF-α, IL-1β (pro inflammatory cytokines) and RANTES, MCP-1 (pro inflammatory chemokines) production in LPS stimulated macrophages. Ginger extract also down regulated the expression of B7.1, B7.2 and MHC class II molecules. In addition ginger extract negatively affected the antigen presenting function of macrophages and we observed a significant reduction in T cell proliferation in response to allostimulation, when ginger extract treated macrophages were used as APCs. A significant decrease in IFN-γ and IL-2 production by T cells in response to allostimulation was also observed. Conclusion In conclusion ginger extract inhibits macrophage activation and APC function and indirectly inhibits T cell activation. PMID:18173849

  15. Stromelysin-2 (MMP10) Moderates Inflammation by Controlling Macrophage Activation.

    PubMed

    McMahan, Ryan S; Birkland, Timothy P; Smigiel, Kate S; Vandivort, Tyler C; Rohani, Maryam G; Manicone, Anne M; McGuire, John K; Gharib, Sina A; Parks, William C

    2016-08-01

    Several members of the matrix metalloproteinase (MMP) family control a range of immune processes, such as leukocyte influx and chemokine activity. Stromelysin-2 (MMP10) is expressed by macrophages in numerous tissues after injury; however, little is known of its function. In this study, we report that MMP10 is expressed by macrophages in human lungs from patients with cystic fibrosis and induced in mouse macrophages in response to Pseudomonas aeruginosa infection both in vivo and by isolated resident alveolar and bone marrow-derived macrophages (BMDM). Our data indicates that macrophage MMP10 serves a beneficial function in response to acute infection. Whereas wild-type mice survived infection with minimal morbidity, 50% of Mmp10(-/-) mice died and all showed sustained weight loss (morbidity). Although bacterial clearance and neutrophil influx did not differ between genotypes, macrophage numbers were ∼3-fold greater in infected Mmp10(-/-) lungs than in wild-types. Adoptive transfer of wild-type BMDM normalized infection-induced morbidity in Mmp10(-/-) recipients to wild-type levels, demonstrating that the protective effect of MMP10 was due to its production by macrophages. Both in vivo and in cultured alveolar macrophages and BMDM, expression of several M1 macrophage markers was elevated, whereas M2 markers were reduced in Mmp10(-/-) tissue and cells. Global gene expression analysis revealed that infection-mediated transcriptional changes persisted in Mmp10(-/-) BMDM long after they were downregulated in wild-type cells. These results indicate that MMP10 serves a beneficial role in response to acute infection by moderating the proinflammatory response of resident and infiltrating macrophages. PMID:27316687

  16. Elimination of Leishmania donovani amastigotes by activated macrophages.

    PubMed Central

    Haidaris, C G; Bonventre, P F

    1981-01-01

    Tissue macrophages are the obligatory host cells for Leishmania donovani, the causative agent of visceral leishmaniasis. In this study we sought to determine whether activated macrophages, as defined by the functional criterion of tumor cell cytotoxicity, were also able to exert a microbicidal effect on ingested L. donovani amastigotes. We found that mouse peritoneal macrophages activated by a variety of means exerted a cytotoxic effect on tumor cell targets but were not able to kill L. donovani amastigotes unless the infected macrophages were exposed continually to an activating stimulus. Corynebacterium parvum, Mycobacterium tuberculosis H37Ra, and lymphokine-activated peritoneal macrophages from C57BL/6J mice were cytotoxic for EMT6 tumor cell targets. However, L. donovani Sudan strain 1S amastigotes were not killed by these macrophages unless the activated state was maintained by daily addition of lymphokine to the infected monolayers for several days postinfection. The killing of amastigotes was dependent on the time of exposure to lymphokine, as well as on the concentration of lymphokine added to the culture. Images PMID:7287190

  17. Evaluation of macrophage antiviral activity in patients affected by neoplasia.

    PubMed

    Merendino, R A; Iannello, D; Arena, A; Bonina, L; Greco, V; Mesiti, M; Chillemi, S; Mastroeni, P

    1988-01-01

    The intrinsic antiviral activity of macrophages has been studied in healthy donors and in patients affected by breast cancer and melanoma. In vitro differentiated macrophages from blood-derived monocytes were infected with measles virus, herpes simplex virus type 2 and adenovirus 17. The challenge was carried out with different multiplicities of infection and the synthesis of virus was tested by evaluating the single cycle growth curve in 24 h. The results obtained show that the restriction of virus infectivity by macrophages is strongly influenced by the multiplicity of infection. This was particularly evident with the adenovirus 17. Moreover, macrophages from patients with melanoma and breast cancer showed an impairment of the intrinsic antiviral activity in comparison with normal subjects. PMID:2842553

  18. Macrophages require different nucleoside transport systems for proliferation and activation.

    PubMed

    Soler, C; García-Manteiga, J; Valdés, R; Xaus, J; Comalada, M; Casado, F J; Pastor-Anglada, M; Celada, A; Felipe, A

    2001-09-01

    To evaluate the mechanisms involved in macrophage proliferation and activation, we studied the regulation of the nucleoside transport systems. In murine bone marrow-derived macrophages, the nucleosides required for DNA and RNA synthesis are recruited from the extracellular medium. M-CSF induced macrophage proliferation and DNA and RNA synthesis, whereas interferon gamma (IFN-gamma) led to activation, blocked proliferation, and induced only RNA synthesis. Macrophages express at least the concentrative systems N1 and N2 (CNT2 and CNT1 genes, respectively) and the equilibrative systems es and ei (ENT1 and ENT2 genes, respectively). Incubation with M-CSF only up-regulated the equilibrative system es. Inhibition of this transport system blocked M-CSF-dependent proliferation. Treatment with IFN-gamma only induced the concentrative N1 and N2 systems. IFN-gamma also down-regulated the increased expression of the es equilibrative system induced by M-CSF. Thus, macrophage proliferation and activation require selective regulation of nucleoside transporters and may respond to specific requirements for DNA and RNA synthesis. This report also shows that the nucleoside transporters are critical for macrophage proliferation and activation. PMID:11532978

  19. The Impact on UT1 Predictions of AAM, OAM, and HAM Forecasts

    NASA Astrophysics Data System (ADS)

    Gross, R. S.

    2011-12-01

    In support of the operational tracking and navigation of interplanetary spacecraft, a Kalman filter has been used at the Jet Propulsion Laboratory (JPL) for nearly three decades to combine independent measurements of the Earth's orientation and to predict its future evolution. Short-term predictions of UT1 are improved when dynamical model-based analyses and forecasts of the axial component of atmospheric angular momentum (AAM) are used as proxy length-of-day measurements and forecasts. Such AAM analyses and forecasts are computed from products generated as part of the numerical weather prediction activities at governmental agencies like the National Centers for Environmental Prediction (NCEP) and the European Centre for Medium-Range Weather Forecasts (ECMWF). At JPL, AAM forecasts from NCEP are currently used to operationally predict UT1. Here the accuracy of JPL's short-term UT1 predictions produced during 01 November 2010 to 30 April 2011 using the NCEP forecasts are compared to the accuracy of the UT1 predictions that would have been produced if ECMWF forecasts had been used instead. The impact on UT1 predictions of additionally incorporating forecasts of oceanic and hydrologic angular momentum is also evaluated.

  20. Secretion of macrophage urokinase plasminogen activator is dependent on proteoglycans.

    PubMed

    Pejler, Gunnar; Winberg, Jan-Olof; Vuong, Tram T; Henningsson, Frida; Uhlin-Hansen, Lars; Kimata, Koji; Kolset, Svein O

    2003-10-01

    The importance of proteoglycans for secretion of proteolytic enzymes was studied in the murine macrophage cell line J774. Untreated or 4beta-phorbol 12-myristate 13-acetate (PMA)-stimulated macrophages were treated with hexyl-beta-d-thioxyloside to interfere with the attachment of glycosaminoglycan chains to their respective protein cores. Activation of the J774 macrophages with PMA resulted in increased secretion of trypsin-like serine proteinase activity. This activity was completely inhibited by plasminogen activator inhibitor 1 and by amiloride, identifying the activity as urokinase plasminogen activator (uPA). Treatment of both the unstimulated or PMA-stimulated macrophages with xyloside resulted in decreased uPA activity and Western blotting analysis revealed an almost complete absence of secreted uPA protein after xyloside treatment of either control- or PMA-treated cells. Zymography analyses with gels containing both gelatin and plasminogen confirmed these findings. The xyloside treatment did not reduce the mRNA levels for uPA, indicating that the effect was at the post-translational level. Treatment of the macrophages with xylosides did also reduce the levels of secreted matrix metalloproteinase 9. Taken together, these findings indicate a role for proteoglycans in the secretion of uPA and MMP-9. PMID:14511379

  1. 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

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

    PubMed

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

    2016-01-01

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

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

    PubMed 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

  4. 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.

  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. Eosinophils Reduce Chronic Inflammation in Adipose Tissue by Secreting Th2 Cytokines and Promoting M2 Macrophages Polarization

    PubMed Central

    Zhang, Yi; Yang, Peng; Cui, Ran; Zhang, Manna; Li, Hong; Qian, Chunhua; Sheng, Chunjun; Qu, Shen; Bu, Le

    2015-01-01

    Obesity is now recognized as a low-grade, chronic inflammatory disease that is linked to a myriad of disorders including cardiovascular diseases, type 2 diabetes, and liver diseases. Recently it is found that eosinophils accelerate alternative activation macrophage (AAM) polarization by secreting Th2 type cytokines such as interleukin-4 and interleukin-13, thereby reducing metainflammation in adipose tissue. In this review, we focused on the role of eosinophils in regulating metabolic homeostasis and obesity. PMID:26688684

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

    PubMed

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

    2012-11-01

    Many studies have demonstrated that the flavonoid quercetin protects against cardiovascular disease (CVD) and related risk factors. Atherosclerosis, the underlying cause of CVD, is also attenuated by oral quercetin administration in animal models. Although macrophages are key players during fatty streak formation and plaque progression and aggravation, little is known about the effects of quercetin on atherogenic macrophages. Here, we report that primary bone marrow-derived macrophages internalized less oxidized low-density lipoprotein (oxLDL) and accumulated less intracellular cholesterol in the presence of quercetin. This reduction of foam cell formation correlated with reduced surface expression of the oxLDL receptor CD36. Quercetin also targeted the lipopolysaccharide-dependent, oxLDL-independent pathway of lipid droplet formation in macrophages. In oxLDL-stimulated macrophages, quercetin inhibited reactive oxygen species production and interleukin (IL)-6 secretion. In a system that evaluated cholesterol crystal-induced IL-1β secretion via nucleotide-binding domain and leucine-rich repeat containing protein 3 inflammasome activation, quercetin also exhibited an inhibitory effect. Dyslipidemic apolipoprotein E-deficient mice chronically treated with intraperitoneal quercetin injections had smaller atheromatous lesions, reduced lipid deposition, and less macrophage and T cell inflammatory infiltrate in the aortic roots than vehicle-treated animals. Serum levels of total cholesterol and the lipid peroxidation product malondialdehyde were also reduced in these mice. Our results demonstrate that quercetin interferes with both key proatherogenic activities of macrophages, namely foam cell formation and pro-oxidant/proinflammatory responses, and these effects may explain the atheroprotective properties of this common flavonoid. PMID:22869926

  8. 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

  9. Dysregulation of Macrophage Activation Profiles by Engineered Nanoparticles

    PubMed Central

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

    2013-01-01

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

  10. ROS play a critical role in the differentiation of alternatively activated macrophages and the occurrence of tumor-associated macrophages

    PubMed Central

    Zhang, Yan; Choksi, Swati; Chen, Kun; Pobezinskaya, Yelena; Linnoila, Ilona; Liu, Zheng-Gang

    2013-01-01

    Differentiation to different types of macrophages determines their distinct functions. Tumor-associated macrophages (TAMs) promote tumorigenesis owing to their proangiogenic and immune-suppressive functions similar to those of alternatively activated (M2) macrophages. We report that reactive oxygen species (ROS) production is critical for macrophage differentiation and that inhibition of superoxide (O2−) production specifically blocks the differentiation of M2 macrophages. We found that when monocytes are triggered to differentiate, O2− is generated and is needed for the biphasic ERK activation, which is critical for macrophage differentiation. We demonstrated that ROS elimination by butylated hydroxyanisole (BHA) and other ROS inhibitors blocks macrophage differentiation. However, the inhibitory effect of ROS elimination on macrophage differentiation is overcome when cells are polarized to classically activated (M1), but not M2, macrophages. More importantly, the continuous administration of the ROS inhibitor BHA efficiently blocked the occurrence of TAMs and markedly suppressed tumorigenesis in mouse cancer models. Targeting TAMs by blocking ROS can be a potentially effective method for cancer treatment. PMID:23752925

  11. Innate immunity and monocyte-macrophage activation in atherosclerosis

    PubMed Central

    2011-01-01

    Innate inflammation is a hallmark of both experimental and human atherosclerosis. The predominant innate immune cell in the atherosclerotic plaque is the monocyte-macrophage. The behaviour of this cell type within the plaque is heterogeneous and depends on the recruitment of diverse monocyte subsets. Furthermore, the plaque microenvironment offers polarisation and activation signals which impact on phenotype. Microenvironmental signals are sensed through pattern recognition receptors, including toll-like and NOD-like receptors - the latter of which are components of the inflammasome - thus dictating macrophage behaviour and outcome in atherosclerosis. Recently cholesterol crystals and modified lipoproteins have been recognised as able to directly engage these pattern recognition receptors. The convergent role of such pathways in terms of macrophage activation is discussed in this review. PMID:21526997

  12. 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

  13. Oxygen tension limits nitric oxide synthesis by activated macrophages.

    PubMed Central

    McCormick, C C; Li, W P; Calero, M

    2000-01-01

    Previous studies have established that constitutive calcium-dependent ('low-output') nitric oxide synthase (NOS) is regulated by oxygen tension. We have investigated the role of oxygen tension in the synthesis of NO by the 'high-output' calcium-independent NOS in activated macrophages. Hypoxia increased macrophage NOS gene expression in the presence of one additional activator, such as lipopolysaccharide or interferon-gamma, but not in the presence of both. Hypoxia markedly reduced the synthesis of NO by activated macrophages (as measured by accumulation of nitrite and citrulline), such that, at 1% oxygen tension, NO accumulation was reduced by 80-90%. The apparent K(m) for oxygen calculated from cells exposed to a range of oxygen tensions was found to be 10.8%, or 137 microM, O(2) This value is considerably higher than the oxygen tension in tissues, and is virtually identical to that reported recently for purified recombinant macrophage NOS. The decrease in NO synthesis did not appear to be due to diminished arginine or cofactor availability, since arginine transport and NO synthesis during recovery in normoxia were normal. Analysis of NO synthesis during hypoxia as a function of extracellular arginine indicated that an altered V(max), but not K(m)(Arg), accounted for the observed decrease in NO synthesis. We conclude that oxygen tension regulates the synthesis of NO in macrophages by a mechanism similar to that described previously for the calcium-dependent low-output NOS. Our data suggest that oxygen tension may be an important physiological regulator of macrophage NO synthesis in vivo. PMID:10970783

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

    PubMed Central

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

    2014-01-01

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

  15. 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

  16. 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…

  17. 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...

  18. Modulation of nitric oxide synthase activity in macrophages

    PubMed Central

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

    1995-01-01

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

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

    PubMed

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

    2016-08-14

    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. PMID:27412794

  20. Plasminogen activator inhibitor-1 stimulates macrophage activation through Toll-like Receptor-4.

    PubMed

    Gupta, Kamlesh K; Xu, Zhi; Castellino, Francis J; Ploplis, Victoria A

    2016-08-26

    While inflammation is often associated with increased Plasminogen Activator Inhibitor-1 (PAI-1), the functional consequences of PAI-1 in inflammation have yet to be fully determined. The aim of this study was to establish the in vivo relevance of PAI-1 in inflammation. A mouse model of systemic inflammation was employed in wild-type (WT) and PAI-1 deficient (PAI-1(-/-)) mice. Mice survival, macrophage infiltration into the lungs, and plasma levels of pro-inflammatory cytokines were assessed after lipopolysaccharide (LPS) infusion. In vitro experiments were conducted to examine changes in LPS-induced inflammatory responses after PAI-1 exposure. PAI-1 was shown to regulate inflammation, in vivo, and affect macrophage infiltration into lungs. Further, PAI-1 activated macrophages, and increased pro-inflammatory cytokines at both the mRNA and protein levels in these cells. The effect of PAI-1 on macrophage activation was dose-dependent and LPS-independent. Proteolytic inhibitory activity and Lipoprotein Receptor-related Protein (LRP) and vitronectin (VN) binding functions, were not involved in PAI-1-mediated activation of macrophages. However, the effect of PAI-1 on macrophage activation was partially blocked by a TLR4 neutralizing antibody. Furthermore, PAI-1-induced Tumor Necrosis Factor-alpha (TNF-α) and Macrophage Inflammatory Protein-2 (MIP-2) expression was reduced in TLR4(-/-) macrophages compared to WT macrophages. These results demonstrate that PAI-1 is involved in the regulation of host inflammatory responses through Toll-like Receptor-4 (TLR4)-mediated macrophage activation. PMID:27317488

  1. 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

  2. Ceramic modifications of porous titanium: effects on macrophage activation.

    PubMed

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

    2012-12-01

    Porous titanium is one of the most widely used implant materials because of its mechanical properties, however, it is also characterised by low bioactivity. To improve the above parameter we prepared three modifications of the porous (30 wt%) titanium (Ti) surface by covering it with bioactive hydroxyapatite (HA), bioglass (BG) and calcium silicate (CS). Subsequently we tested the impact of the modifications on macrophages directing the inflammatory response that might compromise the implant bioactivity. In the study we investigated the in vitro effects of the materials on murine cell line RAW 264.7 macrophage adherence, morphology and activation (production/release of metalloproteinase MMP-9 and pro- and anti-inflammatory cytokines). CS Ti decreased the macrophage adherence and up-regulated the release of several pro-inflammatory mediators, including TNF-α, IL-6, IL-12. Also HA Ti reduced the cell adherence but other parameters were generally not increased, except of TNF-α. In contrast, BG Ti improved macrophage adherence and either decreased production of multiple mediators (MMP-9, TNF-α, IFN-γ, MCP-1) or did not change it in comparison to the porous titanium. We can conclude that analyzing the effects on the inflammatory response initiated by macrophages in vitro, calcium silicate did not improve the biological properties of the porous titanium. The improved bioactivity of titanium was, however, achieved by the application of the hydroxyapatite and bioglass layers. The present in vitro results suggest that these materials, HA Ti and especially BG Ti, may be suitable for in vivo application and thus justify their further investigation. PMID:22939219

  3. A Distinctive Alveolar Macrophage Activation State Induced by Cigarette Smoking

    PubMed Central

    Woodruff, Prescott G.; Koth, Laura L.; Yang, Yee Hwa; Rodriguez, Madeleine W.; Favoreto, Silvio; Dolganov, Gregory M.; Paquet, Agnes C.; Erle, David J.

    2005-01-01

    Rationale: Macrophages are believed to play a central role in emphysema based largely on data from mouse models. However, the relevance of these models to smoking-related lung disease in humans is uncertain. Objectives: We sought to comprehensively characterize the effects of smoking on gene expression in human alveolar macrophages and to compare these with effects seen in transgenic mouse models of emphysema. Methods: We used DNA microarrays with genomewide coverage to analyze alveolar macrophages from 15 smokers, 15 nonsmokers, and 15 subjects with asthma (disease control). Selected gene expression changes were validated by polymerase chain reaction and ELISA. Expression changes were compared with those identified by microarray analysis of interleukin-13–overexpressing and integrin-β6–deficient mice, which both develop emphysema. Measurements and Main Results: All 15 smokers shared a common pattern of macrophage gene expression that distinguished them from nonsmokers, a finding not observed in subjects with asthma. We identified 110 genes as differentially expressed in smokers despite using conservative statistical methods. Matrix metalloproteinase 12, a proteinase that plays a critical role in mouse models, was the third most highly induced gene in smokers (ninefold, p < 0.0001). However, most changes in smokers were not reflected in mouse models. One such finding was increased osteopontin expression in smokers (fourfold, p = 0.006), which was confirmed at the protein level and correlated with the degree of airway obstruction. Conclusions: Smoking induces a remarkably consistent and distinctive pattern of alveolar macrophage activation. These studies identify aspects of mouse models that are directly relevant to human smokers and also reveal novel potential mediators of smoking-related diseases. PMID:16166618

  4. [Macrophage activation syndrome associated with adult-onset Still's disease].

    PubMed

    Iwamoto, Masahiro

    2007-12-01

    Macrophage activation syndrome (MAS) is a rare and potentially lethal disease, resulting from uncontrolled activation and proliferation of T lymphocytes and macrophages. Adult-onset Still's disease (AOSD) is an inflammatory disease. AOSD resemble reactive MAS in its symptoms and laboratory data. Moreover, AOSD per se induces MAS. It is, therefore, quite difficult to differentiate these syndrome and disease. The immunodeficiency state induced by treatment in AOSD could reactivate latent viruses such as Epstein-Barr virus, which could potentially lead to MAS. The therapeutic agents for AOSD, such as sulfasalazine, also could provoke reactive MAS. Because multiple factors are involved in inducing MAS to a different degree, the main cause should be searched for and targeted for the therapy. PMID:18174671

  5. Myelin-Derived Lipids Modulate Macrophage Activity by Liver X Receptor Activation

    PubMed Central

    Huynh-Thu, Vân Anh; Irrthum, Alexandre; Smeets, Hubert J. M.; Gustafsson, Jan-Åke; Steffensen, Knut R.; Mulder, Monique; Stinissen, Piet; Hellings, Niels; Hendriks, Jerome J. A.

    2012-01-01

    Multiple sclerosis is a chronic, inflammatory, demyelinating disease of the central nervous system in which macrophages and microglia play a central role. Foamy macrophages and microglia, containing degenerated myelin, are abundantly found in active multiple sclerosis lesions. Recent studies have described an altered macrophage phenotype after myelin internalization. However, it is unclear by which mechanisms myelin affects the phenotype of macrophages and how this phenotype can influence lesion progression. Here we demonstrate, by using genome wide gene expression analysis, that myelin-phagocytosing macrophages have an enhanced expression of genes involved in migration, phagocytosis and inflammation. Interestingly, myelin internalization also induced the expression of genes involved in liver-X-receptor signaling and cholesterol efflux. In vitro validation shows that myelin-phagocytosing macrophages indeed have an increased capacity to dispose intracellular cholesterol. In addition, myelin suppresses the secretion of the pro-inflammatory mediator IL-6 by macrophages, which was mediated by activation of liver-X-receptor β. Our data show that myelin modulates the phenotype of macrophages by nuclear receptor activation, which may subsequently affect lesion progression in demyelinating diseases such as multiple sclerosis. PMID:22984598

  6. Myelin-derived lipids modulate macrophage activity by liver X receptor activation.

    PubMed

    Bogie, Jeroen F J; Timmermans, Silke; Huynh-Thu, Vân Anh; Irrthum, Alexandre; Smeets, Hubert J M; Gustafsson, Jan-Åke; Steffensen, Knut R; Mulder, Monique; Stinissen, Piet; Hellings, Niels; Hendriks, Jerome J A

    2012-01-01

    Multiple sclerosis is a chronic, inflammatory, demyelinating disease of the central nervous system in which macrophages and microglia play a central role. Foamy macrophages and microglia, containing degenerated myelin, are abundantly found in active multiple sclerosis lesions. Recent studies have described an altered macrophage phenotype after myelin internalization. However, it is unclear by which mechanisms myelin affects the phenotype of macrophages and how this phenotype can influence lesion progression. Here we demonstrate, by using genome wide gene expression analysis, that myelin-phagocytosing macrophages have an enhanced expression of genes involved in migration, phagocytosis and inflammation. Interestingly, myelin internalization also induced the expression of genes involved in liver-X-receptor signaling and cholesterol efflux. In vitro validation shows that myelin-phagocytosing macrophages indeed have an increased capacity to dispose intracellular cholesterol. In addition, myelin suppresses the secretion of the pro-inflammatory mediator IL-6 by macrophages, which was mediated by activation of liver-X-receptor β. Our data show that myelin modulates the phenotype of macrophages by nuclear receptor activation, which may subsequently affect lesion progression in demyelinating diseases such as multiple sclerosis. PMID:22984598

  7. 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. PMID:25953850

  8. Peroxisome proliferator-activated receptor ɣ activation induces 11β-hydroxysteroid dehydrogenase type 1 activity in human alternative macrophages

    PubMed Central

    Chinetti-Gbaguidi, Giulia; Bouhlel, Mohamed Amine; Copin, Corinne; Duhem, Christian; Derudas, Bruno; Neve, Bernardette; Noel, Benoit; Eeckhoute, Jerome; Lefebvre, Philippe; Seckl, Jonathan R.; Staels, Bart

    2012-01-01

    Objectives 11β-hydroxysteroid dehydrogenase type 1 (11β-HSD1) catalyses the intracellular reduction of inactive cortisone to active cortisol, the natural ligand activating the glucocorticoid receptor (GR). Peroxisome Proliferator-Activated Receptor gamma (PPARγ) is a nuclear receptor controlling inflammation, lipid metabolism and the macrophage polarization state. In this study, we investigated the impact of macrophage polarization on the expression and activity of 11β-HSD1 and the role of PPAR therein. Methods and Results 11β-HSD1 gene expression is higher in pro-inflammatory M1 and anti-inflammatory M2 macrophages than in resting macrophages (RM), whereas its activity is highest in M2 macrophages. Interestingly, PPARγ activation induces 11β-HSD1 enzyme activity in M2 macrophages, but not in RM or M1 macrophages. Consequently, human M2 macrophages displayed enhanced responsiveness to the 11β-HSD1 substrate cortisone, an effect amplified by PPAR -induction of 11β-HSD1 activity, as illustrated by an increased expression of GR target genes. Conclusions Our data identify a positive cross-talk between PPARγ and GR in human M2 macrophages via the induction of 11β-HSD1 expression and activity. PMID:22207732

  9. 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. PMID:26382298

  10. Automated detection of pain from facial expressions: a rule-based approach using AAM

    NASA Astrophysics Data System (ADS)

    Chen, Zhanli; Ansari, Rashid; Wilkie, Diana J.

    2012-02-01

    In this paper, we examine the problem of using video analysis to assess pain, an important problem especially for critically ill, non-communicative patients, and people with dementia. We propose and evaluate an automated method to detect the presence of pain manifested in patient videos using a unique and large collection of cancer patient videos captured in patient homes. The method is based on detecting pain-related facial action units defined in the Facial Action Coding System (FACS) that is widely used for objective assessment in pain analysis. In our research, a person-specific Active Appearance Model (AAM) based on Project-Out Inverse Compositional Method is trained for each patient individually for the modeling purpose. A flexible representation of the shape model is used in a rule-based method that is better suited than the more commonly used classifier-based methods for application to the cancer patient videos in which pain-related facial actions occur infrequently and more subtly. The rule-based method relies on the feature points that provide facial action cues and is extracted from the shape vertices of AAM, which have a natural correspondence to face muscular movement. In this paper, we investigate the detection of a commonly used set of pain-related action units in both the upper and lower face. Our detection results show good agreement with the results obtained by three trained FACS coders who independently reviewed and scored the action units in the cancer patient videos.

  11. Inhibition of tristetraprolin expression by dexamethasone in activated macrophages.

    PubMed

    Jalonen, Ulla; Lahti, Aleksi; Korhonen, Riku; Kankaanranta, Hannu; Moilanen, Eeva

    2005-03-01

    Tristetraprolin (TTP) is a factor that regulates mRNA stability and the expression of certain inflammatory genes. In the present study, we found that TTP expression was increased in macrophages exposed to bacterial lipopolysaccharide (LPS). Dexamethasone and dissociated steroid RU24858 inhibited LPS-induced TTP protein and mRNA expression and the inhibitory effect was reversed by a glucocorticoid receptor antagonist mifepristone. Histone deacetylase inhibitors trichostatin A (TSA) and apicidin reduced the inhibitory effect of dexamethasone and RU24858 on TTP expression, but the glucocorticoids did not alter TTP mRNA half-life. These results suggest that anti-inflammatory steroids reduce TTP expression in activated macrophages by a glucocorticoid response element (GRE)-independent mechanism, possibly through histone deacetylation and transcriptional silencing. PMID:15710351

  12. 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

  13. 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

  14. 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

  15. Multimodality PET/MRI agents targeted to activated macrophages.

    PubMed

    Tu, Chuqiao; Ng, Thomas S C; Jacobs, Russell E; Louie, Angelique Y

    2014-02-01

    The recent emergence of multimodality imaging, particularly the combination of PET and MRI, has led to excitement over the prospect of improving detection of disease. Iron oxide nanoparticles have become a popular platform for the fabrication of PET/MRI probes owing to their advantages of high MRI detection sensitivity, biocompatibility, and biodegradability. In this article, we report the synthesis of dextran-coated iron oxide nanoparticles (DIO) labeled with the positron emitter (64)Cu to generate a PET/MRI probe, and modified with maleic anhydride to increase the negative surface charge. The modified nanoparticulate PET/MRI probe (MDIO-(64)Cu-DOTA) bears repetitive anionic charges on the surface that facilitate recognition by scavenger receptor type A (SR-A), a ligand receptor found on activated macrophages but not on normal vessel walls. MDIO-(64)Cu-DOTA has an average iron oxide core size of 7-8 nm, an average hydrodynamic diameter of 62.7 nm, an r1 relaxivity of 16.8 mM(-1) s(-1), and an r 2 relaxivity of 83.9 mM(-1) s(-1) (37 °C, 1.4 T). Cell studies confirmed that the probe was nontoxic and was specifically taken up by macrophages via SR-A. In comparison with the nonmodified analog, the accumulation of MDIO in macrophages was substantially improved. These characteristics demonstrate the promise of MDIO-(64)Cu-DOTA for identification of vulnerable atherosclerotic plaques via the targeting of macrophages. PMID:24166283

  16. 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. PMID:26681460

  17. 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

  18. Targeting macrophage activation for the prevention and treatment of S. aureus biofilm infections†

    PubMed Central

    Hanke, Mark L.; Heim, Cortney E.; Angle, Amanda; Sanderson, Sam D.; Kielian, Tammy

    2013-01-01

    Biofilm infections often lead to significant morbidity due to their chronicity and recalcitrance to antibiotics. We have demonstrated that methicillin-resistant Staphylococcus aureus (MRSA) biofilms can evade macrophage antibacterial effector mechanisms by skewing macrophages towards an alternatively activated M2 phenotype. To overcome this immune evasion, we have utilized two complementary approaches. In the first, a proinflammatory milieu was elicited by local administration of classically-activated M1 macrophages and second, by treatment with the C5a receptor (CD88) agonist EP67, which invokes macrophage proinflammatory activity. Early administration of M1-activated macrophages or EP67 significantly attenuated biofilm formation in a mouse model of MRSA catheter-associated infection. Several proinflammatory mediators were significantly elevated in biofilm infected tissues from macrophage- and EP67-treated animals, revealing effective reprogramming of the biofilm environment to a proinflammatory milieu. A requirement for macrophage proinflammatory activity was demonstrated by the fact that transfer of MyD88-deficient macrophages had minimal impact on biofilm growth. Likewise, neutrophil administration had no effect on biofilm formation. Treatment of established biofilm infections with M1-activated macrophages also significantly reduced catheter-associated biofilm burdens compared to antibiotic treatment. Collectively, these results demonstrate that targeting macrophage proinflammatory activity can overcome the local immune inhibitory environment created during biofilm infections and represents a novel therapeutic strategy. PMID:23365077

  19. Pyrimidinergic Receptor Activation Controls Toxoplasma gondii Infection in Macrophages

    PubMed Central

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

    2015-01-01

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

  20. Successful therapy of macrophage activation syndrome with dexamethasone palmitate.

    PubMed

    Nakagishi, Yasuo; Shimizu, Masaki; Kasai, Kazuko; Miyoshi, Mari; Yachie, Akihiro

    2016-07-01

    Macrophage activation syndrome (MAS) is a severe and potential life-threatening complication of childhood systemic inflammatory disorders. Corticosteroids are commonly used as the first-line therapy for MAS. We report four patients with MAS who were successfully treated with dexamethasone palmitate (DexP), a liposome-incorporated dexamethasone, much more efficient than free corticosteroids. DexP effectively inhibited inflammation in MAS patients in whom the response to pulse methylprednisolone was not sufficient to manage their diseases. DexP was also effective as the first-line therapy for MAS. Based on these findings, DexP is an effective therapy in treating MAS patients. PMID:24754272

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

    PubMed Central

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

    2015-01-01

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

  2. 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.

  3. 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. PMID:26351280

  4. 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

  5. Posttranscriptional control of NLRP3 inflammasome activation in colonic macrophages.

    PubMed

    Filardy, A A; He, J; Bennink, J; Yewdell, J; Kelsall, B L

    2016-07-01

    Colonic macrophages (cMPs) are important for intestinal homeostasis as they kill microbes and yet produce regulatory cytokines. Activity of the NLRP3 (nucleotide-binding leucine-rich repeat-containing pyrin receptor 3) inflammasome, a major sensor of stress and microorganisms that results in pro-inflammatory cytokine production and cell death, must be tightly controlled in the intestine. We demonstrate that resident cMPs are hyporesponsive to NLRP3 inflammasome activation owing to a remarkable level of posttranscriptional control of NLRP3 and pro-interleukin-1β (proIL-1β) protein expression, which was also seen for tumor necrosis factor-α and IL-6, but lost during experimental colitis. Resident cMPs rapidly degraded NLRP3 and proIL-1β proteins by the ubiquitin/proteasome system. Finally, blocking IL-10R-signaling in vivo enhanced NLRP3 and proIL-1β protein but not mRNA levels in resident cMPs, implicating a role for IL-10 in environmental conditioning of cMPs. These data are the first to show dramatic posttranscriptional control of inflammatory cytokine production by a relevant tissue-derived macrophage population and proteasomal degradation of proIL-1β and NLRP3 as a mechanism to control inflammasome activation, findings which have broad implications for our understanding of intestinal and systemic inflammatory diseases. PMID:26627461

  6. 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

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

    PubMed

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

    2015-08-01

    An overwhelming activation of cytotoxic T cells and well-differentiated macrophages leading to systemic overload of inflammatory mediators characterizes the so-called macrophage activation syndrome (MAS); this potentially life-threatening clinical entity may derive from several genetic defects involved in granule-mediated cytotoxicity but has been largely observed in patients with juvenile idiopathic arthritis, many rheumatologic diseases, infections, and malignancies. The occurrence of MAS in the natural history or as the revealing clue of monogenic autoinflammatory disorders (AIDs), rare conditions caused by disrupted innate immunity pathways with overblown release of proinflammatory cytokines, has been only reported in few isolated patients with cryopyrin-associated periodic syndrome, mevalonate kinase deficiency, familial Mediterranean fever, and tumor necrosis factor receptor-associated periodic syndrome since 2001. All these patients displayed various clinical, laboratory, and histopathologic features of MAS and have often required intensive care support. Only one patient has died due to MAS. Defective cytotoxic cell function was documented in a minority of patients. Corticosteroids were the first-line treatment, but anakinra was clinically effective in three refractory cases. Even if MAS and AIDs share multiple clinical features as well as heterogeneous pathogenetic scenes and a potential response to anti-interleukin-1 targeted therapies, MAS requires a prompt specific recognition in the course of AIDs due to its profound severity and high mortality rate. PMID:25846831

  8. Macrophage immunomodulatory activity of polysaccharides isolated from Opuntia polyacantha

    PubMed Central

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

    2008-01-01

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

  9. Macrophage Activation Syndrome-Associated Markers in Severe Dengue.

    PubMed

    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

  10. 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

  11. 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

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

    PubMed

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

    2015-12-01

    Cryptococcus neoformans, the predominant etiological agent of cryptococcosis, is an opportunistic fungal pathogen that primarily affects AIDS patients and patients undergoing immunosuppressive therapy. In immunocompromised individuals, C. neoformans can lead to life-threatening meningoencephalitis. Studies using a virulent strain of C. neoformans engineered to produce gamma interferon (IFN-γ), denoted H99γ, demonstrated that protection against pulmonary C. neoformans infection is associated with the generation of a T helper 1 (Th1)-type immune response and signal transducer and activator of transcription 1 (STAT1)-mediated classical (M1) macrophage activation. However, the critical mechanism by which M1 macrophages mediate their anti-C. neoformans activity remains unknown. The current studies demonstrate that infection with C. neoformans strain H99γ in mice with macrophage-specific STAT1 ablation resulted in severely increased inflammation of the pulmonary tissue, a dysregulated Th1/Th2-type immune response, increased fungal burden, deficient M1 macrophage activation, and loss of protection. STAT1-deficient macrophages produced significantly less nitric oxide (NO) than STAT1-sufficient macrophages, correlating with an inability to control intracellular cryptococcal proliferation, even in the presence of reactive oxygen species (ROS). Furthermore, macrophages from inducible nitric oxide synthase knockout mice, which had intact ROS production, were deficient in anticryptococcal activity. These data indicate that STAT1 activation within macrophages is required for M1 macrophage activation and anti-C. neoformans activity via the production of NO. PMID:26351277

  13. 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.

  14. 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. PMID:26143263

  15. 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

  16. Phagocyte respiratory burst activates macrophage erythropoietin signalling to promote acute inflammation resolution.

    PubMed

    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

  17. Extracellular magnesium and calcium blockers modulate macrophage activity.

    PubMed

    Libako, Patrycja; Nowacki, Wojciech; Castiglioni, Sara; Mazur, Andrzej; Maier, Jeanette A M

    2016-03-01

    Magnesium (Mg) possesses anti-inflammatory properties, partly because it antagonizes calcium (Ca) and inhibits L-type Ca channels. Our aim was to determine the effects of different concentrations of extracellular Mg, with or without Ca-channel blockers, in macrophages. A macrophage-like cell line J774.E was cultured in different concentrations of extracellular Mg and exposed to i) the phorbol ester PMA to induce the production of reactive oxygen species ii) lipopolysaccharide to induce the production of pro-inflammatory cytokines, or iii) ovalbumin to study endocytosis. The Ca antagonists verapamil and/or TMB-8 were used to interfere with Ca homeostasis. Different concentrations of extracellular Mg did not impact on endocytosis, while Ca antagonists markedly decreased it. Low extracellular Mg exacerbated, whereas Ca antagonists inhibited, PMA-induced production of free radicals. Ca blockers prevented lipopolysaccharide-induced transcription and release of IL-1β, IL-6 and TNF-α, while extracellular Mg had only a marginal effect. Ca channel inhibitors markedly reduced the activity of J774.E cells, thus underscoring the critical role of Ca in the non-specific immune response, a role which was, in some instances, also modulated by extracellular Mg. PMID:27160489

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

    PubMed Central

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

    1993-01-01

    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. Images PMID:7504626

  19. 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

  20. Biological markers of macrophage activation: applications for fish phagocytes.

    PubMed Central

    Enane, N A; Frenkel, K; O'Connor, J M; Squibb, K S; Zelikoff, J T

    1993-01-01

    The immune defence mechanisms of fish seem to be related and similarly competent to those of mammals. Because of this, there is an increased interest in the immune responses of fish as models for higher vertebrates in immunological/immunotoxicological studies. Macrophages (M phi), phagocytic cells of the mammalian and teleost immune system which reside in tissues, represent a quiescent population of cells. However, upon stimulation, alterations in the physiology of these resident M phi occur which can be defined in terms of activation. This study was undertaken to determine whether biological markers used to assess mammalian M phi activation are applicable for use with fish M phi. Cells were recovered from the peritoneal cavity of non-injected and Aeromonas salmonicida-injected fish, and differences between resident and elicited M phi were evaluated with respect to protein content, phagocytic competence, enzyme activities and hydrogen peroxide production. Results demonstrate that biological markers used to assess mammalian M phi activation, with the exception of acid phosphatase activity, can be used to characterize the activation state of trout M phi, and that the activation process in both fish and mammals may occur by similar mechanism(s). PMID:8244466

  1. Secretion of monocyte chemotactic activity by alveolar macrophages.

    PubMed Central

    Denholm, E. M.; Wolber, F. M.; Phan, S. H.

    1989-01-01

    The purpose of this study was to determine if alveolar macrophages (AMs) are a source of monocyte chemoattractants and the role bleomycin interaction with AMs may play in the recruitment of monocytes to the lung in a rodent model of bleomycin-induced pulmonary fibrosis. AMs isolated from rats with bleomycin-induced fibrosis secreted significantly greater amounts of monocyte chemoattractants than those isolated from normal rats. When AMs from normal rats were stimulated with bleomycin in vitro, monocyte chemotactic activity was secreted into the medium. Chemotactic activity secretion by AM stimulated with 0.01 to 0.1 micrograms/ml bleomycin was significantly higher than that of cells incubated in medium alone. This activity was truly chemotactic for monocytes, but caused only minimal migration of normal AMs. Bleomycin itself at concentrations of 1 pg/ml to 10 micrograms/ml had no monocyte chemoattractant activity. Characterization of the chemotactic activity in conditioned media (CM) from bleomycin-stimulated AM demonstrated that the major portion of the activity bound to gelatin, was heterogeneous, with estimated molecular weights of 20 to 60 kd, and was inactivated by specific antifibronectin antibody. These findings suggest that fibronectin fragments are primarily responsible for the monocyte chemotactic activity secreted by AMs. Through increased secretion of such chemotactic substances, AMs could play a key role in the recruitment of peripheral blood monocytes into the lung in inflammatory lung disease and fibrosis. PMID:2476935

  2. 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.

  3. 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

  4. 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

  5. Macrophage activation syndrome in the era of biologic therapy.

    PubMed

    Grom, Alexei A; Horne, AnnaCarin; De Benedetti, Fabrizio

    2016-05-01

    Macrophage activation syndrome (MAS) refers to acute overwhelming inflammation caused by a 'cytokine storm'. Although increasingly recognized as a life-threatening complication of various rheumatic diseases, clinically, MAS is strikingly similar to primary and secondary forms of haemophagocytic lymphohistiocytosis (HLH). Not surprisingly, many rheumatologists prefer the term secondary HLH rather than MAS to describe this condition, and efforts to change the nomenclature are in progress. The pathophysiology of MAS remains elusive, but observations in animal models, as well as data on the effects of new anticytokine therapies on rates and clinical presentations of MAS in patients with systemic juvenile idiopathic arthritis (sJIA), provide clues to the understanding of this perplexing clinical phenomenon. In this Review, we explore the latest available evidence and discuss potential diagnostic challenges in the era of increasing use of biologic therapies. PMID:27009539

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

    PubMed

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

    2015-06-10

    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

  8. 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

  9. 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

  10. Hypoxia and classical activation limits Mycobacterium tuberculosis survival by Akt-dependent glycolytic shift in macrophages

    PubMed Central

    Matta, S K; Kumar, D

    2016-01-01

    Cellular reactive oxygen species (ROS) is a major antibacterial defense mechanism used by macrophages upon activation. Exposure of Mycobacterium tuberculosis (Mtb)-infected macrophages to hypoxia is known to compromise the survival of the pathogen. Here we report that the hypoxia-induced control of intracellular Mtb load in RAW 264.7 macrophages was mediated by regulating the cellular ROS levels. We show that similar to classical activation, hypoxia incubation of macrophages resulted in decreased mitochondrial outer membrane potential (MOMP) and a concomitant increase in the cellular ROS levels. Mitochondrial depolarization and consequently higher ROS could be blocked by knocking down Akt using siRNAs, which acted by inhibiting the switch to glycolytic mode of metabolism, an essential adaptive response upon classical activation or hypoxic incubation of macrophages. Moreover, in the classically activated macrophages or in the macrophages under hypoxia incubation, supplementation with additional glucose had similar effects as Akt knockdown. Interestingly, in both the cases, the reversal of phenotype was linked with the ability of the mitochondrial F0–F1 ATP synthase activity to maintain the MOMP in the absence of oxidative phosphorylation. Both Akt knockdown and glucose supplementation were also able to rescue Mtb survival in these macrophages upon classical activation or hypoxia incubation. These results provide a framework for better understanding of how the interplay between oxygen supply, which is limiting in the human tubercular granulomas, and nutrient availability could together direct the outcome of infections in vivo. PMID:27551515

  11. The Impact on EOP Predictions of AAM Forecasts from the ECMWF and NCEP

    NASA Technical Reports Server (NTRS)

    Gross, R. S.; DeViron, O.; VanDam, T.

    2007-01-01

    Predictions of UT1 are improved when dynamical model-based forecasts of the axial component of atmospheric angular momentum (AAM) are used as proxy length-of-day (LOD) forecasts (Freedman et al. 1994; Johnson et al. 2005). For example, the accuracy of JPL's predictions of UT1 are improved by nearly a factor of 2 when AAM forecast data from the National Centers for Environmental Prediction (NCEP) are used. Given the importance of AAM forecasts on the accuracy of UT1 predictions, other sources of AAM forecasts should be sought. Here, the angular momentum of the forecasted wind fields from the European Centre for Medium-Range Weather Forecasts (ECMWF) are computed and used to predict UT1. The results are compared to those obtained using NCEP forecasts.

  12. Modulation of pulmonary macrophage superoxide release and tumoricidal activity following activation by biological response modifiers.

    PubMed

    Drath, D B

    1986-10-01

    Following immunologic activation, pulmonary macrophages may prevent or cause regression of lung metastases by mechanisms which remain largely unknown. The studies described here were designed to determine if enhanced oxygen metabolite release was related to postactivation tumoricidal activity. We have shown that in vitro activation of Fischer 344 rat pulmonary macrophages by either free or liposome-encapsulated muramyl dipeptide leads to both enhanced release of superoxide anions and marked tumoricidal activity against syngenic (Fischer 13762), allogeneic (Schmidt-Ruppin RR 1022) and xenogeneic (Fibrosarcoma MCA-F) 125I-deoxyuridine-labeled target cells. This immune modulator did not, however, metabolically activate pulmonary macrophages as effectively as liposome-encapsulated lipopolysaccharide. A 24-h in vitro incubation with either 150 U or 300 U of interferon-gamma (3 X 10(6) U/mg) or 30 U, 150 U or 300 U of interferon-alpha (6 X 10(5) U/mg) caused a significant elevation in superoxide release above controls, whereas short-term exposure (2 or 4 h) had little or no effect. Free or encapsulated 6-O-stearoyl muramyl dipeptide, on the other hand, did increase superoxide levels at all 3 time periods. When either interferon-gamma or free or encapsulated muramyl dipeptide derivative were administered to intact rats by either i.v. injection, intratracheal instillation or osmotic minipump infusion, pulmonary macrophage tumoricidal activity was observed 96 h after cell harvesting. Zymosan-stimulated superoxide release, however, was not consistently elevated above control or empty liposome treatment following this course of in vivo activation. The data collectively suggest that in vivo pulmonary macrophage activation to a tumoricidal state and metabolic activation resulting in enhanced superoxide may be separable events. PMID:3021650

  13. Macrophages contribute to the cyclic activation of adult hair follicle stem cells.

    PubMed

    Castellana, Donatello; Paus, Ralf; Perez-Moreno, Mirna

    2014-12-01

    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

  14. 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

  15. 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

  16. Macrophage Migration Inhibitory Factor (MIF) Enzymatic Activity and Lung Cancer

    PubMed Central

    Mawhinney, Leona; Armstrong, Michelle E; O’ Reilly, Ciaran; Bucala, Richard; Leng, Lin; Fingerle-Rowson, Gunter; Fayne, Darren; Keane, Michael P; Tynan, Aisling; Maher, Lewena; Cooke, Gordon; Lloyd, David; Conroy, Helen; Donnelly, Seamas C

    2014-01-01

    The cytokine macrophage migration inhibitory factor (MIF) possesses unique tautomerase enzymatic activity, which contributes to the biological functional activity of MIF. In this study, we investigated the effects of blocking the hydrophobic active site of the tautomerase activity of MIF in the pathogenesis of lung cancer. To address this, we initially established a Lewis lung carcinoma (LLC) murine model in Mif-KO and wild-type (WT) mice and compared tumor growth in a knock-in mouse model expressing a mutant MIF lacking enzymatic activity (Mif P1G). Primary tumor growth was significantly attenuated in both Mif-KO and Mif P1G mice compared with WT mice. We subsequently undertook a structure-based, virtual screen to identify putative small molecular weight inhibitors specific for the tautomerase enzymatic active site of MIF. From primary and secondary screens, the inhibitor SCD-19 was identified, which significantly attenuated the tautomerase enzymatic activity of MIF in vitro and in biological functional screens. In the LLC murine model, SCD-19, given intraperitoneally at the time of tumor inoculation, was found to significantly reduce primary tumor volume by 90% (p < 0.001) compared with the control treatment. To better replicate the human disease scenario, SCD-19 was given when the tumor was palpable (at d 7 after tumor inoculation) and, again, treatment was found to significantly reduce tumor volume by 81% (p < 0.001) compared with the control treatment. In this report, we identify a novel inhibitor that blocks the hydrophobic pocket of MIF, which houses its specific tautomerase enzymatic activity, and demonstrate that targeting this unique active site significantly attenuates lung cancer growth in in vitro and in vivo systems. PMID:25826675

  17. 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

  18. 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

  19. 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. PMID:26538237

  20. Peroxidatic activity distinct from myeloperoxidase in human monocytes cultured in vitro and in alveolar macrophages.

    PubMed

    Breton-Gorius, J; Vildé, J L; Guichard, J; Vainchenker, W; Basset, F

    1982-01-01

    Human monocytes develop a peroxidatic activity (PA) in rough endoplasmic reticulum (RER) after adherence or after culture in semi-solid medium. This enzyme activity disappears after three days of culture in the majority of macrophages derived from adult monocytes but persists for one week in macrophages derived from neonatal monocytes. The PA is due to an enzyme distinct from myeloperoxidase (MPO), since monocytes from a patient with MPO deficiency develop the same PA as that of normal monocytes after adherence. By its localization and other characteristics, PA of adherent monocytes resembles that of rodent macrophages. We therefore investigated whether human alveolar macrophages exhibit PA, using a sensitive cytochemical method which prevents inhibition by aldehyde in adherent monocytes. In various pathological cases, four types of macrophages could be identified: the majority were peroxidase-negative, a small percentage was of exudate type exhibiting a PA in granules as blood monocytes, while few macrophages were intermediate, possessing only PA in RER i.e. of type resident and a smaller proportion had PA in RER and in granules i.e. exudate-resident macrophages. These findings demonstrate that human macrophages and adherent monocytes may exhibit PA in RER as has been reported for rodent macrophages. The true nature and function of the enzyme responsible for this PA, which is distinct from MPO, remains unknown, but some arguments seem to suggest its role in prostaglandin synthesis. PMID:6283838

  1. 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

  2. Assimilation Experiments using Geodetic Observations to Diagnose AAM in a Chemistry-Climate Model

    NASA Astrophysics Data System (ADS)

    Neef, Lisa; Matthes, Katja

    2010-05-01

    Variation of the global angular momentum of the atmosphere (AAM) results from fluctuations in the mass-distribution and large-scale wind patterns of the atmosphere. It has moreoever been known for some time that global-scale natural modes of variability (such as ENSO) have clear footprints in the AAM history. Due to exchange of angular momentum between the atmosphere and the solid earth, fluctuations in AAM are reflected in observations of the Earth Rotation Parameters(ERPs). ERPs therefore provide an observational constraint for global climate models, via the simulated AAM. We are planning to assimilate ERPs into the chemistry-climate model ECHAM5/MESSy, to not only improve the agreement with observations but also to better diagnose model deficiencies. As a step toward developing such an assimilation system, we present a comparison between modeled AAM, and the AAM implied by ERP observations. We also illustrate and discuss the problem of extracting information about individual components of a model state from observations of a global integral quantity. This is done via data assimilation experiments in a highly simplified (Lorenz) dynamical system.

  3. 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

  4. Co-existence of classical and alternative activation programs in macrophages responding to Toxoplasma gondii

    PubMed Central

    Patil, Veerupaxagouda; Zhao, Yanlin; Shah, Suhagi; Fox, Barbara A.; Rommereim, Leah M.; Bzik, David J.; Yap, George S.

    2013-01-01

    Pro-inflammatory M1 macrophages are critical for defense against intracellular pathogens while alternatively-activated M2 macrophages mediate tissue homeostasis and repair. Whether these distinct activation programs are mutually exclusive or can co-exist within the same cell is unclear. Here, we report the co-existence of these programs in Toxoplasma gondii-elicited inflammatory macrophages. This is independent of parasite expression of the virulence factor ROP16 and host cell expression of signal transducer and activator of transcription 6 (STAT6). Furthermore, this observation was recapitulated by IFN-γ and IL-4 treated bone marrow-derived macrophages in vitro. These results highlight the multi-functionality of macrophages as they respond to diverse microbial and endogenous stimuli. PMID:24083945

  5. Co-existence of classical and alternative activation programs in macrophages responding to Toxoplasma gondii.

    PubMed

    Patil, Veerupaxagouda; Zhao, Yanlin; Shah, Suhagi; Fox, Barbara A; Rommereim, Leah M; Bzik, David J; Yap, George S

    2014-02-01

    Pro-inflammatory M1 macrophages are critical for defense against intracellular pathogens while alternatively-activated M2 macrophages mediate tissue homeostasis and repair. Whether these distinct activation programs are mutually exclusive or can co-exist within the same cell is unclear. Here, we report the co-existence of these programs in Toxoplasma gondii-elicited inflammatory macrophages. This is independent of parasite expression of the virulence factor ROP16 and host cell expression of signal transducer and activator of transcription 6 (STAT6). Furthermore, this observation was recapitulated by IFN-γ and IL-4 treated bone marrow-derived macrophages in vitro. These results highlight the multi-functionality of macrophages as they respond to diverse microbial and endogenous stimuli. PMID:24083945

  6. 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

  7. 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. PMID:25578260

  8. 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. PMID:26485286

  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. Troglitazone regulates peroxisome proliferator-activated receptors and inducible nitric oxide synthase in murine ovarian macrophages.

    PubMed

    Minge, Cadence E; Ryan, Natalie K; Van Der Hoek, Kylie H; Robker, Rebecca L; Norman, Robert J

    2006-01-01

    Peroxisome proliferator-activated receptor-gamma (PPARG) and PPAR-alpha (PPARA) control metabolic processes in many cell types and act as anti-inflammatory regulators in macrophages. PPAR-activating ligands include thiazolidinediones (TZDs), such as troglitazone, once frequently used to treat insulin resistance as well as symptoms of polycystic ovary syndrome (PCOS). Since macrophages within the ovary mediate optimal follicle development, TZD actions to improve PCOS symptoms are likely to be partly mediated through these specifically localized immune cells. In mouse ovary, PPARG protein was expressed in granulosa cells and in isolated cells localized to theca, stroma, and corpora lutea, consistent with EMR1+ macrophages. Isolation of immune cells (EMR1+ or H2+) showed that Pparg and Ppara were expressed in ovarian macrophages at much higher levels than in peritoneal macrophages. Ovulatory human chorionic gonadotropin downregulated expression of Pparg and Ppara in EMR1+ ovarian macrophages, but no hormonal responsiveness was observed in H2+ cells. Downstream anti-inflammatory effects of PPARG activation were analyzed by in vitro treatment of isolated macrophages with troglitazone. Interleukin-1 beta (Il1b) expression was not altered, and tumor necrosis factor-alpha (Tnf) expression was affected in peritoneal macrophages only. In ovarian macrophages, inducible nitric oxide synthase (Nos2), an important proinflammatory enzyme that regulates ovulation, was significantly reduced by troglitazone treatment, an effect that was restricted to cells from the preovulatory ovary. Thus, expression of PPARs within ovarian macrophages is hormonally regulated, reflecting the changing roles of these cells during the ovulatory cycle. Additionally, ovarian macrophages respond directly to troglitazone to downregulate expression of proinflammatory Nos2, providing mechanistic information about ovarian effects of TZD treatment. PMID:16192401

  11. 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

  12. β-glucans from Coriolus versicolor protect mice against S. typhimurium challenge by activation of macrophages.

    PubMed

    Shi, Shao-Hua; Yang, Wen-Tao; Huang, Ke-Yan; Jiang, Yan-Long; Yang, Gui-Lian; Wang, Chun-Feng; Li, Yu

    2016-05-01

    The effects of β-glucans from Coriolus versicolor (CVP), which are extracted from a well-known immune stimulator C. versicolor, have been demonstrated extensively in vitro and in vivo. However, until now, the phagocytic activity has not been elucidated. Hence, the objective of the present study was to identify the antibacterial activity of CVP or CVP-treated macrophages by an analysis of cell cytotoxicity, phagocytic activity, intracellular bacterial survival, macrophage activation, production of nitric oxide (NO) and expression of inducible nitric oxide synthase (iNOS) in CVP-treated macrophages using flow cytometry, RT-PCR, a gentamicin protection assay, a Nitric oxide assay and an iNOS enzymatic activity assay. The results indicate that CVP-treated macrophages can phagocytize and kill bacteria, probably due to the production of NO and iNOS. More importantly, CVP-treated macrophages are effective at protecting mice against the challenge of Salmonella typhimurium. The results of this study suggest that the antibacterial effects of CVP are probably caused by the activation of innate immune cells, especially macrophages, because the activated macrophage produces NO, which kills bacteria. These phenomena indicate the possibility of CVP as a potential alternative for antibiotics against resistant bacteria. PMID:26802244

  13. Activator of G-Protein Signaling 3-Induced Lysosomal Biogenesis Limits Macrophage Intracellular Bacterial Infection.

    PubMed

    Vural, Ali; Al-Khodor, Souhaila; Cheung, Gordon Y C; Shi, Chong-Shan; Srinivasan, Lalitha; McQuiston, Travis J; Hwang, Il-Young; Yeh, Anthony J; Blumer, Joe B; Briken, Volker; Williamson, Peter R; Otto, Michael; Fraser, Iain D C; Kehrl, John H

    2016-01-15

    Many intracellular pathogens cause disease by subverting macrophage innate immune defense mechanisms. Intracellular pathogens actively avoid delivery to or directly target lysosomes, the major intracellular degradative organelle. In this article, we demonstrate that activator of G-protein signaling 3 (AGS3), an LPS-inducible protein in macrophages, affects both lysosomal biogenesis and activity. AGS3 binds the Gi family of G proteins via its G-protein regulatory (GoLoco) motif, stabilizing the Gα subunit in its GDP-bound conformation. Elevated AGS3 levels in macrophages limited the activity of the mammalian target of rapamycin pathway, a sensor of cellular nutritional status. This triggered the nuclear translocation of transcription factor EB, a known activator of lysosomal gene transcription. In contrast, AGS3-deficient macrophages had increased mammalian target of rapamycin activity, reduced transcription factor EB activity, and a lower lysosomal mass. High levels of AGS3 in macrophages enhanced their resistance to infection by Burkholderia cenocepacia J2315, Mycobacterium tuberculosis, and methicillin-resistant Staphylococcus aureus, whereas AGS3-deficient macrophages were more susceptible. We conclude that LPS priming increases AGS3 levels, which enhances lysosomal function and increases the capacity of macrophages to eliminate intracellular pathogens. PMID:26667172

  14. 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

  15. 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

  16. 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

  17. 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

  18. 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

  19. 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

  20. 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. PMID:26147685

  1. MicroRNAs Control Macrophage Formation and Activation: The Inflammatory Link between Obesity and Cardiovascular Diseases

    PubMed Central

    Chang, Richard Cheng-An; Ying, Wei; Bazer, Fuller W.; Zhou, Beiyan

    2014-01-01

    Activation and recruitment of resident macrophages in tissues in response to physiological stress are crucial regulatory processes in promoting the development of obesity-associated metabolic disorders and cardiovascular diseases. Recent studies have provided compelling evidence that microRNAs play important roles in modulating monocyte formation, macrophage maturation, infiltration into tissues and activation. Macrophage-dependent systemic physiological and tissue-specific responses also involve cell-cell interactions between macrophages and host tissue niche cell components, including other tissue-resident immune cell lineages, adipocytes, vascular smooth muscle and others. In this review, we highlight the roles of microRNAs in regulating the development and function of macrophages in the context of obesity, which could provide insights into the pathogenesis of obesity-related metabolic syndrome and cardiovascular diseases. PMID:25014161

  2. Evidence of drug metabolism by macrophages: possible role of macrophages in the pathogenesis of drug-induced tissue damage and in the activation of environmental procarcinogens.

    PubMed

    Wickramasinghe, S N

    1987-01-01

    After interaction with human macrophages derived from blood, bone marrow or spleen, solutions of sodium phenobarbitone, phenytoin sodium and chlorpromazine hydrochloride showed reduced cytotoxicity towards K562 cells. The reduction in cytotoxicity was partially suppressed in the presence of tetrahydrofurane, an inhibitor of cytochrome P450. These data suggest that macrophages are capable of metabolizing certain drugs, probably via a cytochrome P450-dependent mechanism. The present findings raise the possibility that some drug-induced blood dyscrasias are caused by metabolism of the drug by bone marrow macrophages and the consequent release of relatively short-lived molecules which are toxic to adjacent haemopoietic cells. The generation of cytotoxic molecules during drug metabolism by macrophages may also be responsible for drug-induced damage to other macrophage-rich tissues. In addition, since cytochrome P450-dependent reactions seem to occur within macrophages, these cells may activate environmental procarcinogens and thus plays a role in carcinogenesis and leukaemogenesis. PMID:3652639

  3. Further characterization of macrophage adsorption of suppressor cell activity from tumor-allosensitized spleen

    SciTech Connect

    Zografos-Miller, L.E.; Argyris, B.F.

    1983-06-01

    Suppressor cell activity from P815-allosensitized C57BL/6 spleen can be decreased by incubating the tumor-allosensitized spleen cells on monolayers of thioglycollate-stimulated BDF1 peritoneal macrophages for 2 or 4 hr. The adsorption response appears to be specific for macrophages, because adsorption of suppressor cell activity does not occur following incubation of P815-allosensitized spleen cells on confluent monolayers of mouse spleen cells or mouse embryonic fibroblasts. Pretreatment of macrophage monolayers with X irradiation (2,000 rads) or anti-Thy 1.2 serum (and complement) does not affect their ability to bind suppressor cell activity. Adsorption of suppressor cell activity from P815-allosensitized spleen can also be carried out by proteose peptone-stimulated or Corynebacterium parvum-stimulated macrophages. Blockage of macrophage Fc receptors decreases the ability of thioglycollate-stimulated macrophages to adsorb suppressor cell activity. Monolayers of P815 or P388 cells, two cell types positive for Fc receptors, are unable to adsorb suppressor cell activity from the tumor-allosensitized spleen. The significance of our findings is discussed in terms of the relationship between macrophages and suppressor cells in the immune response to normal or tumor allografts.

  4. Quantitative proteomics analyses of activation states of human THP-1 macrophages.

    PubMed

    Meijer, Kees; Weening, Desiree; de Vries, Marcel P; Priebe, Marion G; Vonk, Roel J; Roelofsen, Han

    2015-10-14

    Macrophages display large functional and phenotypical plasticity. They can adopt a broad range of activation states depending on their microenvironment. Various surface markers are used to characterize these differentially polarized macrophages. However, this is not informative for the functions of the macrophage. In order to have a better understanding of the functional changes of macrophages upon differential polarization, we studied differences in LPS- and IL4-stimulated macrophages. The THP-1 human monocytic cell line, was used as a model system. Cells were labeled, differentiated and stimulated with either LPS or IL-4 in a quantitative SILAC proteomics set-up. The resulting sets of proteins were functionally clustered. LPS-stimulated macrophages show increased secretion of proinflammatory peptides, leading to increased pressure on protein biosynthesis and processing. IL4-stimulated macrophages show upregulation of cell adhesion and extracellular matrix remodeling. Our approach provides an integrated view of polarization-induced functional changes and proves useful for studying functional differences between subsets of macrophages. Moreover, the identified polarization specific proteins may contribute to a better characterization of different activation states in situ and their role in various inflammatory processes. PMID:26200757

  5. Cryopreserved Interleukin-4–Treated Macrophages Attenuate Murine Colitis in an Integrin β7–Dependent Manner

    PubMed Central

    Leung, Gabriella; Petri, Björn; Reyes, José Luis; Wang, Arthur; Iannuzzi, Jordan; McKay, Derek M

    2015-01-01

    The adoptive transfer of alternatively activated macrophages (AAMs) has proven to attenuate inflammation in multiple mouse models of colitis; however, the effect of cryopreservation on AAMs, the ability of previously frozen AAMs to block dinitrobenzene sulfonic acid (DNBS) (Th1) and oxazolone (Th2) colitis and their migration postinjection remains unknown. Here we have found that while cryopreservation reduced mRNA expression of canonical markers of interleukin (IL)-4–treated macrophages [M(IL-4)], this step did not translate to reduced protein or activity, and the cells retained their capacity to drive the suppression of colitis. The anticolitic effect of M(IL-4) adoptive transfer required neither T or B cell nor peritoneal macrophages in the recipient. After injection into the peritoneal cavity, M(IL-4)s migrated to the spleen, mesenteric lymph nodes and colon of DNBS-treated mice. The chemokines CCL2, CCL4 and CX3CL1 were expressed in the colon during the course of DNBS-induced colitis. The expression of integrin β7 on transferred M(IL-4)s was required for their anticolitic effect, whereas the presence of the chemokine receptors CCR2 and CX3CR1 were dispensable in this model. Collectively, the data show that M(IL-4)s can be cryopreserved M(IL-4)s and subsequently used to suppress colitis in an integrin β7-dependent manner, and we suggest that these proof-of-concept studies may lead to new cellular therapies for human inflammatory bowel disease. PMID:26701314

  6. 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

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

    PubMed Central

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

    1995-01-01

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

  8. Genetic programs expressed in resting and IL-4 alternatively activated mouse and human macrophages: similarities and differences.

    PubMed

    Martinez, Fernando O; Helming, Laura; Milde, Ronny; Varin, Audrey; Melgert, Barbro N; Draijer, Christina; Thomas, Benjamin; Fabbri, Marco; Crawshaw, Anjali; Ho, Ling Pei; Ten Hacken, Nick H; Cobos Jiménez, Viviana; Kootstra, Neeltje A; Hamann, Jörg; Greaves, David R; Locati, Massimo; Mantovani, Alberto; Gordon, Siamon

    2013-02-28

    The molecular repertoire of macrophages in health and disease can provide novel biomarkers for diagnosis, prognosis, and treatment. Th2-IL-4–activated macrophages (M2) have been associated with important diseases in mice, yet no specific markers are available for their detection in human tissues. Although mouse models are widely used for macrophage research, translation to the human can be problematic and the human macrophage system remains poorly described. In the present study, we analyzed and compared the transcriptome and proteome of human and murine macrophages under resting conditions (M0) and after IL-4 activation (M2). We provide a resource for tools enabling macrophage detection in human tissues by identifying a set of 87 macrophage-related genes. Furthermore, we extend current understanding of M2 activation in different species and identify Transglutaminase 2 as a conserved M2 marker that is highly expressed by human macrophages and monocytes in the prototypic Th2 pathology asthma. PMID:23293084

  9. Induction of classical activation of macrophage in vitro by water soluble chitin

    NASA Astrophysics Data System (ADS)

    Jeon, Dong-Won; Ahn, Woong Shick; You, Su Jung; Chae, Gue Tae; Shim, Young Bock; Chun, Heung Jae

    2012-12-01

    The purpose of this study is to understand the effect of chitin on macrophage mediated immunity, which is a significant factor to wound healing and tissue regeneration. In this work, water soluble chitin (WSC) was prepared by re-acetylation of chitosan and was treated with the murine RAW 264.7 macrophage cell lines (ATCC TIB-71). WSC induced classical activation in the RAW 264.7 cells, accompanied by the induction of associated genes. The results suggest that WSC is one of the functional chitin molecules that are responsible for the immune response, especially present in macrophage classical activation.

  10. 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.

  11. Polysaccharide of Dendrobium huoshanense activates macrophages via toll-like receptor 4-mediated signaling pathways.

    PubMed

    Xie, Song-Zi; Hao, Ran; Zha, Xue-Qiang; Pan, Li-Hua; Liu, Jian; Luo, Jian-Ping

    2016-08-01

    The present work aimed at investigating the pattern recognition receptor (PRR) and immunostimulatory mechanism of a purified Dendrobium huoshanense polysaccharide (DHP). We found that DHP could bind to the surface of macrophages and stimulate macrophages to secrete NO, TNF-α and IL-1β. To unravel the mechanism for the binding of DHP to macrophages, flow cytometry, confocal laser-scanning microscopy, affinity electrophoresis, SDS-PAGE and western blotting were employed to verify the type of PRR responsible for the recognition of DHP by RAW264.7 macrophages and peritoneal macrophages of C3H/HeN and C3H/HeJ macrophages. Results showed that toll-like receptor 4 (TLR4) was an essential receptor for macrophages to directly bind DHP. Further, the phosphorylation of ERK, JNK, Akt and p38 were observed to be time-dependently promoted by DHP, as well as the nuclear translocation of NF-κB p65. These results suggest that DHP activates macrophages via its direct binding to TLR4 to trigger TLR4 signaling pathways. PMID:27112877

  12. 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

  13. 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

  14. Cot/tpl2 participates in the activation of macrophages by adiponectin

    PubMed Central

    Sanz-Garcia, Carlos; Nagy, Laura E.; Lasunción, Miguel A.; Fernandez, Margarita; Alemany, Susana

    2014-01-01

    Whereas the main function of APN is to enhance insulin activity, it is also involved in modulating the macrophage phenotype. Here, we demonstrate that at physiological concentrations, APN activates Erk1/2 via the IKKβ-p105/NF-κΒ1-Cot/tpl2 intracellular signal transduction cassette in macrophages. In peritoneal macrophages stimulated with APN, Cot/tpl2 influences the ability to phagocytose beads. However, Cot/tpl2 did not modulate the known capacity of APN to decrease lipid content in peritoneal macrophages in response to treatment with oxLDL or acLDL. A microarray analysis of gene-expression profiles in BMDMs exposed to APN revealed that APN modulated the expression of ∼3300 genes; the most significantly affected biological functions were the inflammatory and the infectious disease responses. qRT-PCR analysis of WT and Cot/tpl2 KO macrophages stimulated with APN for 0, 3, and 18 h revealed that Cot/tpl2 participated in the up-regulation of APN target inflammatory mediators included in the cytokine–cytokine receptor interaction pathway (KEGG ID 4060). In accordance with these data, macrophages stimulated with APN increased secretion of cytokines and chemokines, including IL-1β, IL-1α, TNF-α, IL-10, IL-12, IL-6, and CCL2. Moreover, Cot/tpl2 also played an important role in the production of these inflammatory mediators upon stimulation of macrophages with APN. It has been reported that different types of signals that stimulate TLRs, IL-1R, TNFR, FcγR, and proteinase-activated receptor-1 activate Cot/tpl2. Here, we demonstrate that APN is a new signal that activates the IKKβ-p105/NF-κΒ1-Cot/tpl2-MKK1/2-Erk1/2 axis in macrophages. Furthermore, this signaling cassette modulates the biological functions triggered by APN in macrophages. PMID:24532642

  15. Hyperuricemia-induced NLRP3 activation of macrophages contributes to the progression of diabetic nephropathy.

    PubMed

    Kim, Su-Mi; Lee, Sang-Ho; Kim, Yang-Gyun; Kim, Se-Yun; Seo, Jung-Woo; Choi, Young-Wook; Kim, Dong-Jin; Jeong, Kyung-Hwan; Lee, Tae-Won; Ihm, Chun-Gyoo; Won, Kyu-Yeoun; Moon, Ju-Young

    2015-05-01

    IL-1β-secreting nucleotide-binding oligomerization domain protein 3 (NLRP3) inflammasomes play a pivotal role in triggering innate immune responses in metabolic disease. We investigated the role of soluble uric acid in NLRP3 inflammasome activation in macrophages to demonstrate the effect of systemic hyperuricemia on progressive kidney damage in type 2 diabetes. THP-1 cells, human acute monocytic leukemia cells, were cultured to obtain macrophages, and HK-2 cells, human renal proximal tubule cells, were cultured and stimulated with uric acid. In vivo, we designed four rat groups as follows: 1) Long-Evans Tokushima Otsuka (LETO); 2) Otsuka Long-Evans Tokushima Fatty (OLETF); 3) OLETF+high-fructose diet (HFD) for 16 wk; and 4) OLETF+HFD+allopurinol (10 mg/dl administered in the drinking water). Soluble uric acid stimulated NLRP3 inflammasomes to produce IL-1β in macrophages. Uric acid-induced MitoSOX mediates NLRP3 activation and IL-1β secretion. IL-1β from macrophages activates NF-κB in cocultured proximal tubular cells. In vivo, intrarenal IL-1β expression and macrophage infiltration increased in HFD-fed OLETF rats. Lowering the serum uric acid level resulted in improving the albuminuria, tubular injury, macrophage infiltration, and renal IL-1β (60% of HFD-fed OLETF) independently of glycemic control. Direct activation of proximal tubular cells by uric acid resulted in (C-X-C motif) ligand 12 and high mobility group box-1 release and accelerated macrophage recruitment and the M1 phenotype. Taken together, these data support direct roles of hyperuricemia in activating NLRP3 inflammasomes in macrophages, promoting chemokine signaling in the proximal tubule and contributing to the progression of diabetic nephropathy through cross talk between macrophages and proximal tubular cells. PMID:25651569

  16. 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

  17. PPAR activation induces M1 macrophage polarization via cPLA₂-COX-2 inhibition, activating ROS production against Leishmania mexicana.

    PubMed

    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 PPAR γ , 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-1 β , 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

  18. GADD34 inhibits activation-induced apoptosis of macrophages through enhancement of autophagy

    PubMed Central

    Ito, Sachiko; Tanaka, Yuriko; Oshino, Reina; Aiba, Keiko; Thanasegaran, Suganya; Nishio, Naomi; Isobe, Ken-ichi

    2015-01-01

    Autophagy is a common physiological function in all eukaryotes. The process is induced by depletion of nutrients including amino acids. GADD34 is expressed following DNA damage, ER stresses and amino acid deprivation. Here, we investigated the effects of GADD34 on autophagy and cell activation in macrophages. The deprivation of tyrosine and cysteine markedly induced the expression of GADD34 in macrophages. LPS stimulation combined with tyrosine/cysteine-deprivation initially activated macrophages, but then shifted to cell death in late phase of stimulation. When LPS stimulation was combined with tyrosine/cysteine-deprivation, a deficiency of GADD34 enhanced cell activation signaling such as Src-family, Erk1/2, p38 MAPK and Akt. In the late phase of stimulation, a deficiency of GADD34 increased apoptosis more than that in wild-type macrophages. Further we found that mTOR-S6K signaling was highly enhanced in GADD34-deficient macrophages compared with wild-type cells when cells were treated by LPS combined with tyrosine/cysteine-deprivation. LC3-II was increased by LPS stimulation combined with tyrosine/cysteine-deprivation. Defective GADD34 reduced LC3-II and autophagosome formation induced by LPS-stimulation and tyrosine/cysteine-deprivation compared with that seen in wild-type macrophages. These results indicates that GADD34 enhances autophagy and suppresses apoptosis stimulated by LPS combined with amino acid deprivation through regulation of mTOR signaling pathway in macrophages. PMID:25659802

  19. 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

  20. Protease activated receptor-1 regulates macrophage-mediated cellular senescence: a risk for idiopathic pulmonary fibrosis

    PubMed Central

    Lin, Cong; Rezaee, Farhad; Waasdorp, Maaike; Shi, Kun; van der Poll, Tom

    2015-01-01

    Idiopathic pulmonary fibrosis (IPF) is a destructive disease in part resulting from premature or mature cellular aging. Protease-activated receptor-1 (PAR-1) recently emerged as a critical component in the context of fibrotic lung diseases. Therefore, we aimed to study the role of macrophages in PAR-1-mediated idiopathic pulmonary fibrosis. The number of macrophages were significantly reduced in lungs of PAR-1 antagonist (P1pal-12) treated animals upon bleomycin instillation. In line with these data, PAR-1 stimulation increased monocyte/macrophage recruitment in response to epithelium injury in in vitro trans-well assays. Moreover, macrophages induced fibroblasts migration, differentiation and secretion of collagen, which were inhibited in the presence of TGF-β receptor inhibitors. Interestingly, these profibrotic effects were partially inhibited by treatment with the PAR-1 inhibitor P1pal-12. Using shRNA mediated PAR-1 knock down in fibroblasts, we demonstrate that fibroblast PAR-1 contributes to TGF-β activation and production. Finally, we show that the macrophage-dependent induction of PAR-1 driven TGF-β activation was mediated by FXa. Our data identify novel mechanisms by which PAR-1 stimulation on different cell types can contribute to IPF and identify macrophages as key players in PAR-1 dependent development of this devastating disease. IPF may result from cellular senescence mediated by macrophages in the lung. PMID:26474459

  1. Estrogen receptor-alpha promotes alternative macrophage activation during cutaneous repair.

    PubMed

    Campbell, Laura; Emmerson, Elaine; Williams, Helen; Saville, Charis R; Krust, Andrée; Chambon, Pierre; Mace, Kimberly A; Hardman, Matthew J

    2014-09-01

    Efficient local monocyte/macrophage recruitment is critical for tissue repair. Recruited macrophages are polarized toward classical (proinflammatory) or alternative (prohealing) activation in response to cytokines, with tight temporal regulation crucial for efficient wound repair. Estrogen acts as a potent anti-inflammatory regulator of cutaneous healing. However, an understanding of estrogen/estrogen receptor (ER) contribution to macrophage polarization and subsequent local effects on wound healing is lacking. Here we identify, to our knowledge previously unreported, a role whereby estrogen receptor α (ERα) signaling preferentially polarizes macrophages from a range of sources to an alternative phenotype. Cell-specific ER ablation studies confirm an in vivo role for inflammatory cell ERα, but not ERβ, in poor healing associated with an altered cytokine profile and fewer alternatively activated macrophages. Furthermore, we reveal intrinsic changes in ERα-deficient macrophages, which are unable to respond to alternative activation signals in vitro. Collectively, our data reveal that inflammatory cell-expressed ERα promotes alternative macrophage polarization, which is beneficial for timely healing. Given the diverse physiological roles of ERs, these findings will likely be of relevance to many pathologies involving excessive inflammation. PMID:24769859

  2. Impaired activation of Stat1 and c-Jun as a possible defect in macrophages of patients with active tuberculosis.

    PubMed

    Esquivel-Solís, H; Quiñones-Falconi, F; Zarain-Herzberg, A; Amieva-Fernández, R I; López-Vidal, Y

    2009-10-01

    Studies of patients with active tuberculosis (TB) and infected healthy individuals have shown that interferon (IFN)-gamma is present in sites of Mycobacterium tuberculosis infection in comparable levels. This suggests that there is a deficiency in the macrophage response to IFN-gamma in TB patients. We used recombinant human IFN-gamma to stimulate adherent monocyte-derived macrophages from three groups of people: patients with active tuberculosis (TBP), their healthy household contacts (HHC) and healthy uninfected controls from the community (CC). We then evaluated the ability of the macrophages to inhibit the growth of M. tuberculosis H37Rv as well as their cytokine profile at early in infection (48 h). After IFN-gamma treatment, macrophages of healthy individuals (HHC and CC) controlled M. tuberculosis growth and produced mainly nitric oxide (NO) and interleukin (IL)-12p70, whereas TBP macrophages did not kill M. tuberculosis. Additionally, TBP macrophages produced low levels of NO and IL-12p70 and high levels of tumour necrosis factor (TNF)-alpha and IL-10. Transforming growth factor (TGF)-beta levels were similar among all three groups. M. tuberculosis infection had little effect on the cytokine response after IFN-gamma stimulus, but infection alone induced more IL-10 and TGF-beta in TBP macrophages. There were no differences in Stat1 nuclear translocation and DNA binding between the groups. However, the phosphorylated Stat1 and c-Jun (AP-1) in nuclear protein extracts was diminished in TBP macrophages compared to macrophages of healthy individuals. These results indicate an impairment of Stat1-dependent and Stat1-independent IFN-gamma signalling in macrophages of people with active tuberculosis, suggesting a different molecular regulation that could impact macrophage functionality and disease outcome. PMID:19737230

  3. Dissociation of bactericidal activity from other functions of activated macrophages in exudates induced by thioglycolate medium.

    PubMed Central

    Spitalny, G L

    1981-01-01

    Macrophages displayed increased spreading, increased Fc-receptor-mediated phagocytosis, and increased secretion of plasminogen activator when collected from the peritoneal cavities of either Listeria-immune mice challenged intraperitoneally 3 days earlier with Listeria or nonimmune mice injected intraperitoneally 3 days earlier with fluid thioglycolate medium. In contrast, macrophages from the thioglycolate-induced peritoneal exudates were severely impaired in vitro in their ability to destroy Listeria. Injection of thioglycolate markedly interfered with the destruction of sublethal intraperitoneal challenge of Listeria, which resulted in nonimmune animals dying of an overwhelming systemic infection. In animals immune to Listeria, injection of thioglycolate delayed the onset of the expression of immunity to an intraperitoneal challenge of bacteria. The thioglycolate-induced suppression of bactericidal activity was determined to be confined to the site of injection. Results of experiments indicated that the colloidal agar in thioglycolate medium was the cause of the impairment of macrophage bactericidal activity. In addition to the impairment of bactericidal activity induced by agar, additional studies showed that an intraperitoneal injection of colloidal agar (0.075% wt/vol) by itself was a sufficient inflammatory stimulus for the accumulation of a large number of host phagocytic cells. Images PMID:6795125

  4. 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

  5. High salt primes a specific activation state of macrophages, M(Na).

    PubMed

    Zhang, Wu-Chang; Zheng, Xiao-Jun; Du, Lin-Juan; Sun, Jian-Yong; Shen, Zhu-Xia; Shi, Chaoji; Sun, Shuyang; Zhang, Zhiyuan; Chen, Xiao-Qing; Qin, Mu; Liu, Xu; Tao, Jun; Jia, Lijun; Fan, Heng-Yu; Zhou, Bin; Yu, Ying; Ying, Hao; Hui, Lijian; Liu, Xiaolong; Yi, Xianghua; Liu, Xiaojing; Zhang, Lanjing; Duan, Sheng-Zhong

    2015-08-01

    High salt is positively associated with the risk of many diseases. However, little is known about the mechanisms. Here we showed that high salt increased proinflammatory molecules, while decreased anti-inflammatory and proendocytic molecules in both human and mouse macrophages. High salt also potentiated lipopolysaccharide-induced macrophage activation and suppressed interleukin 4-induced macrophage activation. High salt induced the proinflammatory aspects by activating p38/cFos and/or Erk1/2/cFos pathways, while inhibited the anti-inflammatory and proendocytic aspects by Erk1/2/signal transducer and activator of transcription 6 pathway. Consistent with the in vitro results, high-salt diet increased proinflammatory gene expression of mouse alveolar macrophages. In mouse models of acute lung injury, high-salt diet aggravated lipopolysaccharide-induced pulmonary macrophage activation and inflammation in lungs. These results identify a novel macrophage activation state, M(Na), and high salt as a potential environmental risk factor for lung inflammation through the induction of M(Na). PMID:26206316

  6. 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

  7. Model-Based Characterization of Inflammatory Gene Expression Patterns of Activated Macrophages.

    PubMed

    Rex, Julia; Albrecht, Ute; Ehlting, Christian; Thomas, Maria; Zanger, Ulrich M; Sawodny, Oliver; Häussinger, Dieter; Ederer, Michael; Feuer, Ronny; Bode, Johannes G

    2016-07-01

    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

  8. The mycotoxin deoxynivalenol inhibits the cell surface expression of activation markers in human macrophages.

    PubMed

    Waché, Yann J; Hbabi-Haddioui, Laila; Guzylack-Piriou, Laurence; Belkhelfa, Haouaria; Roques, Christine; Oswald, Isabelle P

    2009-08-21

    Deoxynivalenol (DON) is the most prevalent trichothecene mycotoxin in crops in Europe and North America. It exhibits several toxic effects including impaired growth and immune dysregulation. Macrophages play pivotal role in the host defense; upon activation, they express several specific cell surface receptors that are important in adhesion and cell signaling. Several studies have demonstrated that DON can affect macrophages, however, very few data are available concerning the effect of DON on human macrophages, and the effect on macrophage cell surface receptors is unknown. In the present study, human blood monocytes, differentiated in vitro into macrophages, were activated with IFN-gamma, in the presence or absence of low concentrations of DON. The expression of CD11c, CD13, CD14, CD18, CD33, CD35, CD54, CD119 and HLA-DP/DQ/DR was analyzed by flow cytometry. As expected, macrophage activation by IFN-gamma upregulated the expression of CD54, CD14, CD119 and HLA-DP/DQ/DR. Incubation with DON decrease the cell surface expression of these activation markers in a dose-dependent manner. When cells were treated with 5muM DON, the mean fluorescence intensity measured for the expression of these receptors was the same as that observed in non-activated macrophages. This inhibitory effect of DON was only observed when the mycotoxin was applied before the activation signal. Taken together, our results suggest that low concentration of DON alter macrophage activation as measured by the expression of cell surface markers. This may have implications for human health when consuming DON contaminated feed. PMID:19549553

  9. 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

  10. Unfolding the relationship between secreted molecular chaperones and macrophage activation states

    PubMed Central

    Henderson, Samantha

    2008-01-01

    Over the last 20 years, it has emerged that many molecular chaperones and protein-folding catalysts are secreted from cells and function, somewhat in the manner of cytokines, as pleiotropic signals for a variety of cells, with much attention being focused on the macrophage. During the last decade, it has become clear that macrophages respond to bacterial, protozoal, parasitic and host signals to generate phenotypically distinct states of activation. These activation states have been termed ‘classical’ and ‘alternative’ and represent not a simple bifurcation in response to external signals but a range of cellular phenotypes. From an examination of the literature, the hypothesis is propounded that mammalian molecular chaperones are able to induce a wide variety of alternative macrophage activation states, and this may be a system for relating cellular or tissue stress to appropriate macrophage responses to restore homeostatic equilibrium. PMID:18958583

  11. Clinical utility of the liposteroid therapy: Potential effects on the macrophage activation.

    PubMed

    Wakiguchi, Hiroyuki; Ohga, Shouichi

    2016-01-01

      Liposteroid, a lipid emulsion containing dexamethasone, was developed in Japan. This drug is effective against rheumatoid arthritis, and has fewer side effects than dexamethasone. Moreover, at high dosage, liposteroid has been effectively used for the treatment of macrophage activation syndrome, because the lipid emulsions are easily taken up by phagocytes, and are retained in macrophages. Its anti-inflammatory effect was found to be 2-5 times higher than that of dexamethasone in arthritis and granuloma rat models. Japanese researchers have reported the clinical efficacy and utility of liposteroid in the treatment of diseases with macrophage activation. These include hemophagocytic lymphohistiocytosis, graft-versus-host disease, and pulmonary hemosiderosis. Here, we describe the clinical effects of liposteroid on macrophage activation syndrome and the hypothalamus-pituitary-adrenal axis in patients. PMID:27320934

  12. Human lung tissue macrophages, but not alveolar macrophages, express matrix metalloproteinases after direct contact with activated T lymphocytes.

    PubMed

    Ferrari-Lacraz, S; Nicod, L P; Chicheportiche, R; Welgus, H G; Dayer, J M

    2001-04-01

    Human alveolar macrophages (AM) and lung tissue macrophages (LTM) have a distinct localization in the cellular environment. We studied their response to direct contact with activated T lymphocytes in terms of the production of interstitial collagenase (MMP-1), 92-kD gelatinase (MMP-9), and of TIMP-1, one of the counter-regulatory tissue inhibitors of metalloproteinases. Either AM obtained by bronchoalveolar lavage or LTM obtained by mincing and digestion of lung tissue were exposed for 48 h to plasma membranes of T lymphocytes previously activated with phorbol myristate acetate and phytohemagglutinin for 24 h. Membranes of activated T cells strongly induced the production of MMP-1, MMP-9, and TIMP-1 exclusively in LTM but not in AM, whereas membranes from unstimulated T cells failed to induce the release of MMPs. Both populations of mononuclear phagocytes spontaneously released only small amounts of MMPs and TIMP-1. Similar results were obtained when MMP and TIMP-1 expression was analyzed at pretranslational and biosynthetic levels, respectively. Blockade experiments with cytokine antagonists revealed the involvement of T-cell membrane-associated interleukin-1 and tumor necrosis factor-alpha in MMP production by LTM upon contact with T cells. These data suggest that the ability of lung macrophages to produce MMPs after direct contact with activated T cells is related to the difference in phenotype of mononuclear phagocytes and cell localization. In addition, these observations indicate that cell-cell contact represents an important biological mechanism in potentiating the inflammatory response of mononuclear phagocytes in the lungs. PMID:11306438

  13. 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. PMID:24722209

  14. Macrophage activation and migration in interface tissue around loosening total hip arthroplasty components.

    PubMed

    Ishiguro, N; Kojima, T; Ito, T; Saga, S; Anma, H; Kurokouchi, K; Iwahori, Y; Iwase, T; Iwata, H

    1997-06-01

    The bone-cement interface tissue of failed total hip arthroplasty (THA) has inflammatory characteristics, such as the presence of prostaglandin E2 and interleukin 1 (IL-1). We considered that the bone-cement interface tissue could be the site of granulomatous inflammation caused by a foreign-body reaction. It has been demonstrated that inflammatory cytokines and chemokines have an important role in granulomatous inflammation. Bone-cement interface tissue was obtained at revision from nine patients with failed cemented THA, and the role of macrophages was assessed by immunohistochemistry, electron microscopy, and molecular biological techniques. We used the reverse-transcriptional polymerase chain reaction to examine the expression of mRNA for IL-1 alpha, IL-1 beta, tumor necrosis factor alpha (TNF alpha), macrophage inflammatory protein (MIP)-1 alpha, MIP-1 beta, IL-8, and monocyte chemoattractant protein. Polyethylene debris surrounded by macrophages and phagocytosis of debris by macrophages was frequently observed in the interface tissue. Macrophage activation and the production of inflammatory cytokines such as IL-1 and TNF alpha might induce the development of interface tissue. Expression of chemokine mRNAs was also commonly seen, suggesting that this led to recruitment of macrophages into the bone-cement interface tissue. Debris released from implants appears to cause activation of macrophages and the production of inflammatory cytokines and chemokines that induce cellular recruitment into interface tissue. This mechanism might form a vicious cycle that aggravates THA loosening. PMID:9138074

  15. 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

  16. 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. PMID:26296370

  17. 3D Fast Automatic Segmentation of Kidney Based on Modified AAM and Random Forest.

    PubMed

    Jin, Chao; Shi, Fei; Xiang, Dehui; Jiang, Xueqing; Zhang, Bin; Wang, Ximing; Zhu, Weifang; Gao, Enting; Chen, Xinjian

    2016-06-01

    In this paper, a fully automatic method is proposed to segment the kidney into multiple components: renal cortex, renal column, renal medulla and renal pelvis, in clinical 3D CT abdominal images. The proposed fast automatic segmentation method of kidney consists of two main parts: localization of renal cortex and segmentation of kidney components. In the localization of renal cortex phase, a method which fully combines 3D Generalized Hough Transform (GHT) and 3D Active Appearance Models (AAM) is applied to localize the renal cortex. In the segmentation of kidney components phase, a modified Random Forests (RF) method is proposed to segment the kidney into four components based on the result from localization phase. During the implementation, a multithreading technology is applied to speed up the segmentation process. The proposed method was evaluated on a clinical abdomen CT data set, including 37 contrast-enhanced volume data using leave-one-out strategy. The overall true-positive volume fraction and false-positive volume fraction were 93.15%, 0.37% for renal cortex segmentation; 83.09%, 0.97% for renal column segmentation; 81.92%, 0.55% for renal medulla segmentation; and 80.28%, 0.30% for renal pelvis segmentation, respectively. The average computational time of segmenting kidney into four components took 20 seconds. PMID:26742124

  18. Schistosoma mansoni Hemozoin Modulates Alternative Activation of Macrophages via Specific Suppression of Retnla Expression and Secretion

    PubMed Central

    Truscott, Martha; Evans, D. Andrew; Gunn, Matt

    2013-01-01

    The trematode Schistosoma mansoni is one of the etiological agents of schistosomiasis, a key neglected tropical disease responsible for an estimated annual loss of 70 million disability-adjusted life years. Hematophagy represents the primary nutrient acquisition pathway of this parasite, but digestion of hemoglobin also liberates toxic heme. Schistosomes detoxify heme via crystallization into hemozoin, which is subsequently regurgitated into the host's circulation. Here we demonstrate that during experimental schistosomiasis, hemozoin accumulating in the mouse liver is taken up by phagocytes at a time coincident with the development of the egg-induced T-helper 2 (Th2) granulomatous immune response. Furthermore, the uptake of hemozoin also coincides with the hepatic expression of markers of alternative macrophage activation. Alternatively activated macrophages are a key effector cell population associated with protection against schistosomiasis, making hemozoin well placed to play an important immunomodulatory role in this disease. To systematically explore this hypothesis, S. mansoni hemozoin was purified and added to in vitro bone marrow-derived macrophage cultures concurrently exposed to cytokines chosen to reflect the shifting state of macrophage activation in vivo. Macrophages undergoing interleukin-4 (IL-4)-induced alternative activation in the presence of hemozoin developed a phenotype specifically lacking in Retnla, a characteristic alternatively activated macrophage product associated with regulation of Th2 inflammatory responses. As such, in addition to its important detoxification role during hematophagy, we propose that schistosome hemozoin also provides a potent immunomodulatory function in the coevolved network of host-parasite relationships during schistosomiasis. PMID:23090958

  19. TGFβ signaling plays a critical role in promoting alternative macrophage activation

    PubMed Central

    2012-01-01

    Background Upon stimulation with different cytokines, macrophages can undergo classical or alternative activation to become M1 or M2 macrophages. Alternatively activated (or M2) macrophages are defined by their expression of specific gene products and play an important role in containing inflammation, removing apoptotic cells and repairing tissue damage. Whereas it is well-established that IL-4 can drive alternative activation, if lack of TGFβ signaling at physiological levels affects M2 polarization has not been addressed. Results Vav1-Cre x TβRIIfx/fx mice, lacking TβRII function in hematopoietic cells, exhibited uncontrolled pulmonary inflammation and developed a lethal autoimmune syndrome at young age. This was accompanied by significantly increased numbers of splenic neutrophils and T cells as well as elevated hepatic macrophage infiltration and bone marrow monocyte counts. TβRII-/- CD4+ and CD8+ T-cells in the lymph nodes and spleen expressed increased cell surface CD44, and CD69 was also higher on CD4+ lymph node T-cells. Loss of TβRII in bone marrow-derived macrophages (BMDMs) did not affect the ability of these cells to perform efferocytosis. However, these cells were defective in basal and IL-4-induced arg1 mRNA and Arginase-1 protein production. Moreover, the transcription of genes that are typically upregulated in M2-polarized macrophages, such as ym1, mcr2 and mgl2, was also decreased in peritoneal macrophages and IL-4-stimulated TβRII-/- BMDMs. We found that cell surface and mRNA expression of Galectin-3, which also regulates M2 macrophage polarization, was lower in TβRII-/- BMDMs. Very interestingly, the impaired ability of these null mutant BMDMs to differentiate into IL-4 polarized macrophages was Stat6- and Smad3-independent, but correlated with reduced levels of phospho-Akt and β-catenin. Conclusions Our results establish a novel biological role for TGFβ signaling in controlling expression of genes characteristic for alternatively

  20. 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 ...

  1. Immunologic activity of lipopolysaccharides released from macrophages after the uptake of intact E coli in vitro

    SciTech Connect

    Duncan, R.L. Jr.; Hoffman, J.; Tesh, V.L.; Morrison, D.C.

    1986-04-15

    Lipopolysaccharides (LPS) have been isolated from culture supernatants and from cell lysates after the in vitro phagocytosis of E. coli by murine macrophages. By using E. coli radiolabeled specifically in the LPS component with (/sup 3/H)galactose, the authors studies have shown that the macrophage-processed LPS is enhanced with respect to its immunostimulatory activity in comparison with control phenol-water-extracted LPS. As assessed by its ability to induce interluekin 1 production in naive macrophages or proliferation in cultures of murine splenocytes, the macrophage-processed LPS is between 10- and 100-fold greater in specific activity. Evidence is presented for both structural and chemical alterations in the LPS macromolecule.

  2. 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

  3. 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

  4. 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

  5. Effect of cinnamon water extract on monocyte-to-macrophage differentiation and scavenger receptor activity

    PubMed Central

    2014-01-01

    Background Water soluble cinnamon extract has been shown to increase insulin sensitivity and modulate macrophage activation, a desirable trait for the management of obesity or atherosclerosis. Our present study investigated whether cinnamon water extract (CWE) may influence the differentiation of monocytes into macrophages and the activity of macrophage scavenger receptors, commonly observed in atherosclerotic lesions. Methods We investigated the effect of CWE on the expression of various surface markers and the uptake of acetylated low density lipoprotein (LDL) in phorbol-12-myristate-13-acetate (PMA)-stimulated THP-1 cells. The protein levels of PMA or macrophage-colony stimulating factor (M-CSF)-stimulated type 1 macrophage scavenger receptor (SRA) were analyzed. Finally, the role of extracellar signal-related kinase (ERK) 1/2 in SRA synthesis and the effect of CWE on PMA-stimulated ERK1/2 were determined. Results CWE inhibited the differentiation of monocyte by decreasing the expression of CD11b, CD36 and SRA and the uptake of acetyl LDL. CWE suppressed the upregulation of SRA by M-CSF and modulated ERK1/2 activity, which was required for PMA-induced SRA synthesis. Conclusions Our results demonstrate that CWE was able to interfere with monocyte differentiation and macrophage scavenger activity, indicating its potential in preventing the development of atherosclerotic lesions. PMID:24602512

  6. The age-related neuroinflammatory environment promotes macrophage activation, which negatively impacts synaptic function.

    PubMed

    Costello, Derek A; Keenan, Kathryn; McManus, Róisín M; Falvey, Aidan; Lynch, Marina A

    2016-07-01

    The impact of infiltration of macrophages into the brain is debatable with evidence of both beneficial and detrimental effects. Recent work suggests that inflammatory macrophages, with an inflammatory phenotype that resembles the M1 activation state, may be detrimental, whereas anti-inflammatory M2-like macrophages may be beneficial. We set up a model to examine the response of bone marrow-derived macrophages to the inflammatory milieu that occurs in the aged brain. Expression of MHCII and CD40 was increased in macrophages incubated with soluble brain extract prepared from aged, compared with young, mice and this was accompanied by increased production of tumor necrosis factor-α and interleukin-6. Analysis of soluble brain extract indicated that it contained increased concentrations of several inflammatory mediators and, importantly, when bone marrow-derived macrophages were incubated in the inflammatory cytokines that were increased and applied to hippocampal slices, long-term potentiation was inhibited. The data suggest that infiltrating macrophages respond to local conditions and, in the case of aging, adopt an inflammatory phenotype that ultimately has a neurodetrimental effect. PMID:27255823

  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. The chemokine system in diverse forms of macrophage activation and polarization.

    PubMed

    Mantovani, Alberto; Sica, Antonio; Sozzani, Silvano; Allavena, Paola; Vecchi, Annunciata; Locati, Massimo

    2004-12-01

    Plasticity and functional polarization are hallmarks of the mononuclear phagocyte system. Here we review emerging key properties of different forms of macrophage activation and polarization (M1, M2a, M2b, M2c), which represent extremes of a continuum. In particular, recent evidence suggests that differential modulation of the chemokine system integrates polarized macrophages in pathways of resistance to, or promotion of, microbial pathogens and tumors, or immunoregulation, tissue repair and remodeling. PMID:15530839

  9. High and low molecular weight hyaluronic acid differentially influence macrophage activation

    PubMed Central

    Rayahin, Jamie E.; Buhrman, Jason S.; Zhang, Yu; Koh, Timothy J.; Gemeinhart, Richard A.

    2015-01-01

    Macrophages exhibit phenotypic diversity permitting wide-ranging roles in maintaining physiologic homeostasis. Hyaluronic acid, a major glycosaminoglycan of the extracellular matrix, has been shown to have differential signaling based on its molecular weight. With this in mind, the main objective of this study was to elucidate the role of hyaluronic acid molecular weight on macrophage activation and reprogramming. Changes in macrophage activation were assessed by activation state selective marker measurement, specifically quantitative real time polymerase chain reaction, and cytokine enzyme-linked immunoassays, after macrophage treatment with differing molecular weights of hyaluronic acid under four conditions: the resting state, concurrent with classical activation, and following inflammation involving either classically or alternatively activated macrophages. Regardless of initial polarization state, low molecular weight hyaluronic acid induced a classically activated-like state, confirmed by up-regulation of pro-inflammatory genes, including nos2, tnf, il12b, and cd80, and enhanced secretion of nitric oxide and TNF-α. High molecular weight hyaluronic acid promoted an alternatively activated-like state, confirmed by up regulation of pro-resolving gene transcription, including arg1, il10, and mrc1, and enhanced arginase activity. Overall, our observations suggest that macrophages undergo phenotypic changes dependent on molecular weight of hyaluronan that correspond to either (1) pro-inflammatory response for low molecular weight HA or (2) pro-resolving response for high molecular weight HA. These observations bring significant further understanding of the influence of extracellular matrix polymers, hyaluronic acid in particular, on regulating the inflammatory response of macrophages. This knowledge can be used to guide the design of HA-containing biomaterials to better utilize the natural response to HAs. PMID:26280020

  10. 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

  11. Methamphetamine inhibits Toll-like receptor 9-mediated anti-HIV activity in macrophages.

    PubMed

    Cen, Ping; Ye, Li; Su, Qi-Jian; Wang, Xu; Li, Jie-Liang; Lin, Xin-Qin; Liang, Hao; Ho, Wen-Zhe

    2013-08-01

    Toll-like receptor 9 (TLR9) is one of the key sensors that recognize viral infection/replication in the host cells. Studies have demonstrated that methamphetamine (METH) dysregulated host cell innate immunity and facilitated HIV infection of macrophages. In this study, we present new evidence that METH suppressed TLR9-mediated anti-HIV activity in macrophages. Activation of TLR9 by its agonist CpG-ODN 2216 inhibits HIV replication, which was demonstrated by increased expression of TLR9, interferon (IFN)-α, IFN regulatory factor-7 (IRF-7), myeloid differentiation factor 88 (MyD88), and myxovirus resistance gene A (MxA) in macrophages. However, METH treatment of macrophages greatly compromised the TLR9 signaling-mediated anti-HIV effect and inhibited the expression of TLR9 downstream signaling factors. Dopamine D1 receptor (D1R) antagonists (SCH23390) could block METH-mediated inhibition of anti-HIV activity of TLR9 signaling. Investigation of the underlying mechanisms of the METH action showed that METH treatment selectively down-regulated the expression of TLR9 on macrophages, whereas it had little effect on the expression of other TLRs. Collectively, our results provide further evidence that METH suppresses host cell innate immunity against HIV infection by down-regulating TLR9 expression and its signaling-mediated antiviral effect in macrophages. PMID:23751096

  12. Phenotypic, functional, and plasticity features of classical and alternatively activated human macrophages.

    PubMed

    Tarique, Abdullah A; Logan, Jayden; Thomas, Emma; Holt, Patrick G; Sly, Peter D; Fantino, Emmanuelle

    2015-11-01

    Macrophages are dynamic cells that mature under the influence of signals from the local microenvironment into either classically (M1) or alternatively (M2) activated macrophages with specific functional and phenotypic properties. Although the phenotypic identification of M1 and M2 macrophages is well established in mice, this is less clear for human macrophages. In addition, the persistence and reversibility of polarized human phenotypes is not well established. Human peripheral blood monocytes were differentiated into uncommitted macrophages (M0) and then polarized to M1 and M2 phenotypes using LPS/IFN-γ and IL-4/IL-13, respectively. M1 and M2 were identified as CD64(+)CD80(+) and CD11b(+)CD209(+), respectively, by flow cytometry. Polarized M1 cells secreted IP-10, IFN-γ, IL-8, TNF-α, IL-1β, and RANTES, whereas M2 cells secreted IL-13, CCL17, and CCL18. Functionally, M2 cells were highly endocytic. In cytokine-deficient medium, the polarized macrophages reverted back to the M0 state within 12 days. If previously polarized macrophages were given the alternative polarizing stimulus after 6 days of resting in cytokine-deficient medium, a switch in polarization was seen (i.e., M1 macrophages switched to M2 and expressed CD11b(+)CD209(+) and vice versa). In summary, we report phenotypic identification of human M1 and M2 macrophages, their functional characteristics, and their ability to be reprogrammed given the appropriate stimuli. PMID:25870903

  13. 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

  14. Interleukin-6 signaling promotes alternative macrophage activation to limit obesity-associated insulin resistance and endotoxemia

    PubMed Central

    Mauer, Jan; Chaurasia, Bhagirath; Goldau, Julia; Vogt, Merly C.; Ruud, Johan; Nguyen, Khoa D.; Theurich, Sebastian; Hausen, A. Christine; Schmitz, Joel; Brönneke, Hella S.; Estevez, Emma; Allen, Tamara L.; Mesaros, Andrea; Partridge, Linda; Febbraio, Mark A.; Chawla, Ajay; Wunderlich, F. Thomas; Brüning, Jens C.

    2014-01-01

    Obesity and insulin resistance are closely associated with the development of low-grade inflammation. Interleukin 6 (IL-6) is linked to obesity-associated inflammation, however its role in this context remains controversial. Here, we show that mice with inactivated Il6ra gene in myeloid cells (Il6raΔmyel) displayed exaggerated deterioration of glucose homeostasis upon diet-induced obesity due to enhanced insulin resistance. Insulin target tissues showed increased inflammation and a shift in macrophage polarization. IL-6 induced IL-4-receptor expression and augmented the response to IL-4 in macrophages in a cell-autonomous manner. Il6raΔmyel mice were resistant to IL-4-mediated alternative macrophage polarization and exhibited increased susceptibility to LPS-induced endotoxemia. These results reveal IL-6 signaling as an important determinant for alternative macrophage-activation and assign IL-6 an unexpected homeostatic role to limit inflammation. PMID:24681566

  15. Regulation of plasminogen activator inhibitor-1 and urokinase by hyaluronan fragments in mouse macrophages.

    PubMed

    Horton, M R; Olman, M A; Bao, C; White, K E; Choi, A M; Chin, B Y; Noble, P W; Lowenstein, C J

    2000-10-01

    Pulmonary inflammation and fibrosis are characterized by increased turnover and production of the extracellular matrix as well as an impairment of lung fibrinolytic activity. Although fragments of the extracellular matrix component hyaluronan induce macrophage production of inflammatory mediators, the effect of hyaluronan on the fibrinolytic mediators plasminogen activator inhibitor (PAI)-1 and urokinase-type plasminogen activator (uPA) is unknown. This study demonstrates that hyaluronan fragments augment steady-state mRNA, protein, and inhibitory activity of PAI-1 as well as diminish the baseline levels of uPA mRNA and inhibit uPA activity in an alveolar macrophage cell line. Hyaluronan fragments alter macrophage expression of PAI-1 and uPA at the level of gene transcription. Similarly, hyaluronan fragments augment PAI-1 and diminish uPA mRNA levels in freshly isolated inflammatory alveolar macrophages from bleomycin-treated rats. These data suggest that hyaluronan fragments influence alveolar macrophage expression of PAI-1 and uPA and may be a mechanism for regulating fibrinolytic activity during lung inflammation. PMID:11000131

  16. 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

  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. PMID:23634218

  18. 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

  19. 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...

  20. 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

  1. 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

  2. Aspects Of 40- to 50-Day Oscillations In LOD And AAM

    NASA Technical Reports Server (NTRS)

    Dickey, Jean O.; Marcus, Steven L.; Ghil, Michael

    1992-01-01

    Report presents study of fluctuations in rotation of Earth, focusing on irregular intraseasonal oscillations in length of day (LOD) and atmospheric angular momentum (AAM) with periods varying from 40 to 50 days. Study draws upon and extends results of prior research.

  3. 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

  4. 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

  5. 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

  6. 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

  7. Activation of a distinct subpopulation of pulmonary macrophages following exposure to biological response modifiers.

    PubMed

    Drath, D B; Do, C; Burd, T; Hong, L L

    1994-03-01

    A distinct subpopulation of tissue-associated pulmonary macrophages (TAPM) displayed tumoricidal activity towards syngeneic and xenogeneic targets following in vitro incubation with N-acetylmuramyl-L-alanyl-D-isoglutamine (MDP). This subpopulation, as well as, the predominant population of freely lavagable alveolar macrophages destroyed allogeneic targets following a similar incubation with either 6-0-stearoyl MDP (S-MDP) or recombinant interferon-gamma (IFN-gamma). IFN-gamma-induced in vivo tumoricidal activation of both populations of pulmonary macrophage was most effective when delivered either intravenously or via osmotic minipump infusion and least effective when administered by direct intratracheal instillation. The separate populations also displayed in vivo activation in response to liposome-encapsulated i.v. administered S-MDP. Under comparable conditions, IFN-alpha was not nearly as effective. Metabolic activation of TAPM, assessed by the release of increased levels of superoxide free radicals during phagocytosis, occurred following 24 hr exposure to S-MDP or lipopolysaccharide. Incorporation of these agents into multilamellar vesicle liposomes further augmented the release of superoxide observed at 24 hrs. Our results collectively demonstrated that a subpopulation of lung macrophage, a tissue-associated pulmonary macrophage, may be activated to a tumoricidal state and to release pronounced levels of oxygen free radicals following either in vitro or in situ treatment with several biological response modifiers. PMID:8194852

  8. Telomerase Activation in Atherosclerosis and Induction of Telomerase Reverse Transcriptase Expression by Inflammatory Stimuli in Macrophages

    PubMed Central

    Gizard, Florence; Heywood, Elizabeth B.; Findeisen, Hannes M.; Zhao, Yue; Jones, Karrie L.; Cudejko, Cèline; Post, Ginell R.; Staels, Bart; Bruemmer, Dennis

    2010-01-01

    Objective Telomerase serves as a critical regulator of tissue renewal. Although telomerase activity is inducible in response to various environmental cues, it remains unknown whether telomerase is activated during the inflammatory remodeling underlying atherosclerosis formation. To address this question, we investigated in the present study the regulation of telomerase in macrophages and during atherosclerosis development in LDL-receptor-deficient mice. Methods and Results We demonstrate that inflammatory stimuli activate telomerase in macrophages by inducing the expression of the catalytic subunit telomerase reverse transcriptase (TERT). Reporter and chromatin immunoprecipitation assays identified a previously unrecognized NF-κB response element in the TERT promoter, to which NF-κB is recruited during inflammation. Inhibition of NF-κB signaling completely abolished the induction of TERT expression, characterizing TERT as a bona fide NF-κB target gene. Furthermore, functional experiments revealed that TERT-deficiency results in a senescent cell phenotype. Finally, we demonstrate high levels of TERT expression in macrophages of human atherosclerotic lesions and establish that telomerase is activated during atherosclerosis development in LDL-receptor-deficient mice. Conclusion These results characterize TERT as a previously unrecognized NF-κB target gene in macrophages and demonstrate that telomerase is activated during atherosclerosis. This induction of TERT expression prevents macrophage senescence and may have important implications for the development of atherosclerosis. PMID:21106948

  9. Immunocytochemical Localization of Latent Transforming Growth Factor-B1 Activation by Stimulated Macrophages

    SciTech Connect

    Chong, Hyonkyong; Vodovotz, Yoram; Cox, G.W.; Barcellos-Hoff, M.H.

    1998-09-22

    Transforming growth factor-{beta}1 (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.

  10. 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.

  11. IRAK-M promotes alternative macrophage activation and fibroproliferation in bleomycin-induced lung injury.

    PubMed

    Ballinger, Megan N; Newstead, Michael W; Zeng, Xianying; Bhan, Urvashi; Mo, Xiaokui M; Kunkel, Steven L; Moore, Bethany B; Flavell, Richard; Christman, John W; Standiford, Theodore J

    2015-02-15

    Idiopathic pulmonary fibrosis is a devastating lung disease characterized by inflammation and the development of excessive extracellular matrix deposition. Currently, there are only limited therapeutic intervenes to offer patients diagnosed with pulmonary fibrosis. Although previous studies focused on structural cells in promoting fibrosis, our study assessed the contribution of macrophages. Recently, TLR signaling has been identified as a regulator of pulmonary fibrosis. IL-1R-associated kinase-M (IRAK-M), a MyD88-dependent inhibitor of TLR signaling, suppresses deleterious inflammation, but may paradoxically promote fibrogenesis. Mice deficient in IRAK-M (IRAK-M(-/-)) were protected against bleomycin-induced fibrosis and displayed diminished collagen deposition in association with reduced production of IL-13 compared with wild-type (WT) control mice. Bone marrow chimera experiments indicated that IRAK-M expression by bone marrow-derived cells, rather than structural cells, promoted fibrosis. After bleomycin, WT macrophages displayed an alternatively activated phenotype, whereas IRAK-M(-/-) macrophages displayed higher expression of classically activated macrophage markers. Using an in vitro coculture system, macrophages isolated from in vivo bleomycin-challenged WT, but not IRAK-M(-/-), mice promoted increased collagen and α-smooth muscle actin expression from lung fibroblasts in an IL-13-dependent fashion. Finally, IRAK-M expression is upregulated in peripheral blood cells from idiopathic pulmonary fibrosis patients and correlated with markers of alternative macrophage activation. These data indicate expression of IRAK-M skews lung macrophages toward an alternatively activated profibrotic phenotype, which promotes collagen production, leading to the progression of experimental pulmonary fibrosis. PMID:25595781

  12. 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

  13. Enhancement of carrier-mediated transport after immunologic activation of peritoneal macrophages.

    PubMed

    Bonventre, P F; Straus, D; Baughn, R E; Imhoff, J

    1977-05-01

    Immunologically activated peritoneal macrophages from inbred mice and Hartley strain guinea pigs demonstrate a markedly greater than normal transport of 2-deoxy-D-glucose and L-leucine. The degree of nutrilite transport enhancement was greatest when animals were injected with the appropriate eliciting antigens before harvesting and also, if antigen was included in the tissue culture medium during the initial hours of in vitro culture. Enhanced hexose and amino acid uptake could also be achieved by exposure of macrophages from nonimmunized animals for 48 hr to supernatants of sensitized splenic lymphocyte cultures incubated with specific antigens. The animal systems in which this phenomenon was observed included CBA/J and C57BL/6J mice immunized with Staphylococcus aureus or sub-lethal doses of Listeria monocytogens, and the Hartley strain, albino guinea pig immunized with S. aureus or BCG. In all cases, immunization resulted in a state of delayed hypersensitivity as measured by skin testing or footpad swelling. Splenic cell supernatants contained lymphokines as detected by the presence of macrophage inhibitory factor (MIF), and by the supernatants' capacity to stimulate incorporation of 14C-glucosamine by macrophages in vitro. No increase of glucose or leucine transport by macrophages was observed in the absence of appropriate antigen stimulation in vivo or in vitro. We previously showed that a phagocytic stimulus results in a significant increase in hexose transport by normal macrophages; leucine transport by these same cells was unaltered after phagocytosis. In contrast, immunologically activated macrophages do not transport measurably more 2-deoxy-C-glucose after particle ingestion; activation or the phagocytic stimulus enhance 2-deoxy-C-glucose uptake to approximately the same extent. Analysis of nutrilite transport kinetics revealed that immunologic activation of macrophages increases the initial velocity (V1) and Vmax but does not change the Km values of

  14. 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.

  15. Enhancement of phagocytotic activity by prion protein in PrP-deficient macrophage cells.

    PubMed

    Uraki, Ryuta; Sakudo, Akikazu; Ando, Saeko; Kitani, Hiroshi; Onodera, Takashi

    2010-10-01

    Macrophages, especially follicular dendritic cells, contribute to the pathogenesis of prion diseases by accumulating an abnormal isoform of prion protein (PrPSc), which is converted from the cellular isoform of prion protein (PrPC). As information on the function of PrPC in macrophages is limited, we have established a prion protein (PrP) gene (Prnp)-deficient macrophage cell line from the bone marrow of ZrchI Prnp-/- mice. These cells expressed macrophage specific proteins (F4/80 and MOMA-2) and displayed phagocytotic properties. The Prnp-/- macrophage cell line (MplZ) showed shorter pseudopodium extension and less phagocytotic activity than a Prnp+/+ macrophage cell line (MWF). In addition, the MplZ cells were more sensitive to serum deprivation than the MWF cells and underwent apoptotic cell death in these conditions. These findings suggest that PrPC enhances the incorporation of materials possibly including PrPSc and decreases the sensitivity of cells to oxidative stress, which may be induced by PrPSc accumulation. PMID:20818492

  16. Pseudomonas aeruginosa Triggers Macrophage Autophagy To Escape Intracellular Killing by Activation of the NLRP3 Inflammasome

    PubMed Central

    Deng, Qiuchan; Wang, Yi; Zhang, Yuanqing; Li, Meiyu; Li, Dandan; Huang, Xi; Wu, Yongjian; Pu, Jieying

    2015-01-01

    Assembly of the inflammasome has recently been identified to be a critical event in the initiation of inflammation. However, its role in bacterial killing remains unclear. Our study demonstrates that Pseudomonas aeruginosa infection induces the assembly of the NLRP3 inflammasome and the sequential secretion of caspase1 and interleukin-1β (IL-1β) in human macrophages. More importantly, activation of the NLRP3 inflammasome reduces the killing of P. aeruginosa in human macrophages, without affecting the generation of antimicrobial peptides, reactive oxygen species, and nitric oxide. In addition, our results demonstrate that P. aeruginosa infection increases the amount of the LC3-II protein and triggers the formation of autophagosomes in human macrophages. The P. aeruginosa-induced autophagy was enhanced by overexpression of NLRP3, ASC, or caspase1 but was reduced by knockdown of these core molecules of the NLRP3 inflammasome. Treatment with IL-1β enhanced autophagy in human macrophages. More importantly, IL-1β decreased the macrophage-mediated killing of P. aeruginosa, whereas knockdown of ATG7 or Beclin1 restored the IL-1β-mediated suppression of bacterial killing. Collectively, our study explores a novel mechanism employed by P. aeruginosa to escape from phagocyte killing and may provide a better understanding of the interaction between P. aeruginosa and host immune cells, including macrophages. PMID:26467446

  17. Immunostimulatory activity of polysaccharides isolated from Caulerpa lentillifera on macrophage cells.

    PubMed

    Maeda, Reiko; Ida, Tomoaki; Ihara, Hideshi; Sakamoto, Tatsuji

    2012-01-01

    Polysaccharides were extracted from Caulerpa lentillifera by treating with water and then purified by size-exclusion chromatography. The purified polysaccharides, termed SP1, were found to be sulfated xylogalactans with a molecular mass of more than 100 kDa. Adding SP1 to murine macrophage RAW 264.7 cells increased the production of nitric oxide (NO) in a dose-dependent manner. NO was found by immunoblotting and RT-PCR analyses to be synthesized by an inducible NO synthase. SP1 caused the degradation of IκB-α and the nuclear translocation of nuclear factor (NF)-κB subunit p65 in macrophage cells. SP1 also increased the phosphorylation of p38 mitogen-activated protein kinase (MAPK). These results demonstrate that SP1 activated macrophage cells via both the NF-κB and p38 MAPK signaling pathways. Moreover, SP1 increased the expression of various genes encoding cytokines, and the phagocytic activity of macrophage cells. These combined results show that SP1 immunostimulated the activity of macrophage cells. PMID:22451391

  18. Epigenetic Control of Macrophage Shape Transition towards an Atypical Elongated Phenotype by Histone Deacetylase Activity.

    PubMed

    Cabanel, Mariana; Brand, Camila; Oliveira-Nunes, Maria Cecilia; Cabral-Piccin, Mariela Pires; Lopes, Marcela Freitas; Brito, Jose Marques; de Oliveira, Felipe Leite; El-Cheikh, Marcia Cury; Carneiro, Katia

    2015-01-01

    Inflammatory chronic pathologies are complex processes characterized by an imbalance between the resolution of the inflammatory phase and the establishment of tissue repair. The main players in these inflammatory pathologies are bone marrow derived monocytes (BMDMs). However, how monocyte differentiation is modulated to give rise to specific macrophage subpopulations (M1 or M2) that may either maintain the chronic inflammatory process or lead to wound healing is still unclear. Considering that inhibitors of Histone Deacetylase (HDAC) have an anti-inflammatory activity, we asked whether this enzyme would play a role on monocyte differentiation into M1 or M2 phenotype and in the cell shape transition that follows. We then induced murine bone marrow progenitors into monocyte/macrophage differentiation pathway using media containing GM-CSF and the HDAC blocker, Trichostatin A (TSA). We found that the pharmacological inhibition of HDAC activity led to a shape transition from the typical macrophage pancake-like shape into an elongated morphology, which was correlated to a mixed M1/M2 profile of cytokine and chemokine secretion. Our results present, for the first time, that HDAC activity acts as a regulator of macrophage differentiation in the absence of lymphocyte stimuli. We propose that HDAC activity down regulates macrophage plasticity favoring the pro-inflammatory phenotype. PMID:26196676

  19. Classically Activated Macrophages Use Stable Microtubules for Matrix Metalloproteinase-9 (MMP-9) Secretion*

    PubMed Central

    Hanania, Raed; Song Sun, He; Xu, Kewei; Pustylnik, Sofia; Jeganathan, Sujeeve; Harrison, Rene E.

    2012-01-01

    As major effector cells of the innate immune response, macrophages must adeptly migrate from blood to infected tissues. Endothelial transmigration is accomplished by matrix metalloproteinase (MMP)-induced degradation of basement membrane and extracellular matrix components. The classical activation of macrophages with LPS and IFN-γ causes enhanced microtubule (MT) stabilization and secretion of MMPs. Macrophages up-regulate MMP-9 expression and secretion upon immunological challenge and require its activity for migration during the inflammatory response. However, the dynamics of MMP-9 production and intracellular distribution as well as the mechanisms responsible for its trafficking are unknown. Using immunofluorescent imaging, we localized intracellular MMP-9 to small Golgi-derived cytoplasmic vesicles that contained calreticulin and protein-disulfide isomerase in activated RAW 264.7 macrophages. We demonstrated vesicular organelles of MMP-9 aligned along stable subsets of MTs and showed that selective modulation of MT dynamics contributes to the enhanced trafficking of MMP-9 extracellularly. We found a Rab3D-dependent association of MMP-9 vesicles with the molecular motor kinesin, whose association with the MT network was greatly enhanced after macrophage activation. Finally, we implicated kinesin 5B and 3B isoforms in the effective trafficking of MMP-9 extracellularly. PMID:22270361

  20. Forced Activation of Notch in Macrophages Represses Tumor Growth by Upregulating miR-125a and Disabling Tumor-Associated Macrophages.

    PubMed

    Zhao, Jun-Long; Huang, Fei; He, Fei; Gao, Chun-Chen; Liang, Shi-Qian; Ma, Peng-Fei; Dong, Guang-Ying; Han, Hua; Qin, Hong-Yan

    2016-03-15

    Tumor-associated macrophages (TAM) contribute greatly to hallmarks of cancer. Notch blockade was shown to arrest TAM differentiation, but the precise role and underlying mechanisms require elucidation. In this study, we employed a transgenic mouse model in which the Notch1 intracellular domain (NIC) is activated conditionally to define the effects of active Notch1 signaling in macrophages. NIC overexpression had no effect on TAM differentiation, but it abrogated TAM function, leading to repressed growth of transplanted tumors. Macrophage miRNA profiling identified a novel downstream mediator of Notch signaling, miR-125a, which was upregulated through an RBP-J-binding site at the first intronic enhancer of the host gene Spaca6A. miR-125a functioned downstream of Notch signaling to reciprocally influence polarization of M1 and M2 macrophages by regulating factor inhibiting hypoxia inducible factor-1α and IRF4, respectively. Notably, macrophages transfected with miR-125a mimetics increased phagocytic activity and repressed tumor growth by remodeling the immune microenvironment. We also identified a positive feedback loop for miR-125a expression mediated by RYBP and YY1. Taken together, our results showed that Notch signaling not only supported the differentiation of TAM but also antagonized their protumorigenic function through miR-125a. Targeting this miRNA may reprogram macrophages in the tumor microenvironment and restore their antitumor potential. PMID:26759236

  1. Cripto-1 modulates macrophage cytokine secretion and phagocytic activity via NF-κB signaling.

    PubMed

    Zhang, Dong-mei; Bao, Yong-Li; Yu, Chun-Lei; Wang, Yi-meng; Song, Zhen-Bo

    2016-02-01

    Cripto-1 is an oncogenic protein belonging to the epidermal growth factor–Cripto-1/FRL-1/Cryptic family. It has important roles in tumor formation and metastasis, but its effects on the immune system are unclear. In the present study, we investigated the effects of Cripto-1 overexpression on macrophage activities and examined the underlying mechanisms. A cell line stably overexpressing Cripto-1 was developed. The culture supernatant from this cell line was collected and used to condition macrophages (RAW264.7, THP-1, and primary mouse macrophages) for various times. Exposure to this supernatant significantly increased the mRNA and protein expression levels of the anti-inflammatory cytokine interleukin (IL)-10 and of three pro-inflammatory cytokines (tumor necrosis factor-α, IL-6, and IL-1β), but did not affect the expression of transforming growth factor-β, another anti-inflammatory cytokine. Exposure to this supernatant also enhanced macrophage phagocytosis of chicken erythrocytes and yeast cells. Similar effects were observed in macrophages stimulated with purified Cripto-1 protein. Mechanistic experiments revealed that Cripto-1 activated nuclear factor (NF)-κB signaling by inducing IκB kinase phosphorylation and p65 nuclear translocation. Pretreatment with ammonium pyrrolidine dithiocarbamate, a specific NF-κB inhibitor, inhibited Cripto-1-induced cytokine secretion and phagocytosis of macrophages. Taken together, our present findings suggest that Cripto-1 enhances macrophage phagocytic activity and upregulates the production of anti- and pro-inflammatory cytokines via the NF-κB signaling pathway. PMID:26476731

  2. Carbon Nanotube-Induced Pulmonary Granulomatous Disease: Twist1 and Alveolar Macrophage M1 Activation

    PubMed Central

    Barna, Barbara P.; Huizar, Isham; Malur, Anagha; McPeek, Matthew; Marshall, Irene; Jacob, Mark; Dobbs, Larry; Kavuru, Mani S.; Thomassen, Mary Jane

    2013-01-01

    Sarcoidosis, a chronic granulomatous disease of unknown cause, has been linked to several environmental risk factors, among which are some that may favor carbon nanotube formation. Using gene array data, we initially observed that bronchoalveolar lavage (BAL) cells from sarcoidosis patients displayed elevated mRNA of the transcription factor, Twist1, among many M1-associated genes compared to healthy controls. Based on this observation we hypothesized that Twist1 mRNA and protein expression might become elevated in alveolar macrophages from animals bearing granulomas induced by carbon nanotube instillation. To address this hypothesis, wild-type and macrophage-specific peroxisome proliferator-activated receptor gamma (PPARγ) knock out mice were given oropharyngeal instillation of multiwall carbon nanotubes (MWCNT). BAL cells obtained 60 days later exhibited significantly elevated Twist1 mRNA expression in granuloma-bearing wild-type or PPARγ knock out alveolar macrophages compared to sham controls. Overall, Twist1 expression levels in PPARγ knock out mice were higher than those of wild-type. Concurrently, BAL cells obtained from sarcoidosis patients and healthy controls validated gene array data: qPCR and protein analysis showed significantly elevated Twist1 in sarcoidosis compared to healthy controls. In vitro studies of alveolar macrophages from healthy controls indicated that Twist1 was inducible by classical (M1) macrophage activation stimuli (LPS, TNFα) but not by IL-4, an inducer of alternative (M2) macrophage activation. Findings suggest that Twist1 represents a PPARγ-sensitive alveolar macrophage M1 biomarker which is induced by inflammatory granulomatous disease in the MWCNT model and in human sarcoidosis. PMID:24322444

  3. 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

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

    PubMed

    Pinilla-Vera, Miguel; Xiong, Zeyu; 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

  5. 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

  6. 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

  7. Activation of macrophages by the ophiopogon polysaccharide liposome from the root tuber of Ophiopogon japonicus.

    PubMed

    Sun, Wenjing; Hu, Wenjie; Meng, Kai; Yang, Lumiao; Zhang, Weimin; Song, Xiaoping; Qu, Xiaohao; Zhang, Yueyang; Ma, Lin; Fan, Yunpeng

    2016-10-01

    This study evaluated the immunomodulatory effects of ophiopogon polysaccharide liposome (OPL) on macrophages in vitro. The phagocytic activity, the secretion of nitric oxide (NO) and inducible nitric oxide synthase (iNOS), the level of cytokines, chemokines and the expression of CD14 and MHC-II costimulatory molecules were measured. Results showed that OPL could significantly improve the phagocytic activity and the level of IL-1β, TNF-α, MCP-1 and MIP-1β, promote the secretion of NO and iNOS, and enhance the expression of CD14 and MHC-II costimulatory molecules in the peritoneal macrophages of mice compared with ophiopogon polysaccharide (OP). Altogether, these results suggested that OPL could activate macrophages, and the efficacy was significantly superior to OP. Therefore, OPL would be exploited in a potent immunomodulators. Moreover, it also provided the theoretical basis for further studying the mechanism of OPL on improving the immune response. PMID:27311507

  8. 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

  9. Anti-inflammatory activity and mechanism of surfactin in lipopolysaccharide-activated macrophages.

    PubMed

    Zhang, Yuanyuan; Liu, Chuan; Dong, Bin; Ma, Xiaolei; Hou, Lihua; Cao, Xiaohong; Wang, Chunling

    2015-04-01

    Surfactin is primarily produced by Bacillus natto TK-1 and is one of the most powerful biosurfactants. It consists of a heptapeptide interlinked with a β-hydroxy fatty acid. Because of its special structure, surfactin shows broad biological effects, including anti-tumour, anti-microbial and anti-mycoplasma activities. It also has potential anti-inflammatory activity; however, the anti-inflammatory mechanism of surfactin has not been explored. In this study, we investigated the anti-inflammatory mechanism of surfactin in lipopolysaccharide (LPS)-stimulated macrophages. Surfactin exhibited an anti-inflammatory effect without cytotoxicity at certain concentrations, and the lipopolysaccharide (LPS)-stimulated cells appeared normal after surfactin treatment. Surfactin significantly inhibited the increased expression of IFN-γ, IL-6, iNOS and nitric oxide (NO). TLR4 is the critical receptor for LPS; therefore, the TLR4 signal transduction pathway is the primary pathway that mediates LPS-induced inflammation. The results show that surfactin downregulated the LPS-induced TLR4 protein expression of macrophages and indicated that the surfactin-mediated signal pathway was involved in with TLR4. The subsequent studies demonstrated that surfactin exhibited anti-inflammatory effects by attenuating the activation of nuclear factor-κB (NF-κB), which is involved in the nuclear factor-κB (NF-κB) cell signalling pathways. These results suggest that surfactin may be a new therapeutic agent for inflammation. PMID:25331175

  10. 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

  11. TRIM33 switches off Ifnb1 gene transcription during the late phase of macrophage activation

    PubMed Central

    Ferri, Federica; Parcelier, Aude; Petit, Vanessa; Gallouet, Anne-Sophie; Lewandowski, Daniel; Dalloz, Marion; van den Heuvel, Anita; Kolovos, Petros; Soler, Eric; Squadrito, Mario Leonardo; De Palma, Michele; Davidson, Irwin; Rousselet, Germain; Romeo, Paul-Henri

    2015-01-01

    Despite its importance during viral or bacterial infections, transcriptional regulation of the interferon-β gene (Ifnb1) in activated macrophages is only partially understood. Here we report that TRIM33 deficiency results in high, sustained expression of Ifnb1 at late stages of toll-like receptor-mediated activation in macrophages but not in fibroblasts. In macrophages, TRIM33 is recruited by PU.1 to a conserved region, the Ifnb1 Control Element (ICE), located 15 kb upstream of the Ifnb1 transcription start site. ICE constitutively interacts with Ifnb1 through a TRIM33-independent chromatin loop. At late phases of lipopolysaccharide activation of macrophages, TRIM33 is bound to ICE, regulates Ifnb1 enhanceosome loading, controls Ifnb1 chromatin structure and represses Ifnb1 gene transcription by preventing recruitment of CBP/p300. These results characterize a previously unknown mechanism of macrophage-specific regulation of Ifnb1 transcription whereby TRIM33 is critical for Ifnb1 gene transcription shutdown. PMID:26592194

  12. Regulation of retinoid mediated cholesterol efflux involves liver X receptor activation in mouse macrophages.

    PubMed

    Manna, Pulak R; Sennoune, Souad R; Martinez-Zaguilan, Raul; Slominski, Andrzej T; Pruitt, Kevin

    2015-08-14

    Removal of cholesterol from macrophage-derived foam cells is a critical step to the prevention of atherosclerotic lesions. We have recently demonstrated the functional importance of retinoids in the regulation of the steroidogenic acute regulatory (StAR) protein that predominantly mediates the intramitochondrial transport of cholesterol in target tissues. In the present study, treatment of mouse macrophages with retinoids, particularly all-trans retinoic acid (atRA) and 9-cis RA, resulted in increases in cholesterol efflux to apolipoprotein AI (Apo-A1). Activation of the PKA pathway by a cAMP analog, (Bu)2cAMP, markedly augmented retinoid mediated cholesterol efflux. Macrophages overexpressing hormone-sensitive lipase increased the hydrolysis of cholesteryl esters and concomitantly enhanced the efficacy of retinoic acid receptor and liver X receptor (LXR) ligands on StAR and ATP-binding cassette transporter A1 (ABCA1) protein levels. RAs elevated StAR promoter activity in macrophages, and an increase in StAR levels augmented cholesterol efflux to Apo-A1, suggesting retinoid-mediated efflux of cholesterol involves enhanced oxysterol production. Further studies revealed that retinoids activate the LXR regulated genes, sterol receptor-element binding protein-1c and ABCA1. These findings provide insights into the regulatory events in which retinoid signaling effectively enhances macrophage cholesterol efflux and indicate that retinoid therapy may have important implications in limiting and/or regressing atherosclerotic cardiovascular disease. PMID:26119689

  13. Activation of Alveolar Macrophages via the Alternative Pathway in Herpesvirus-Induced Lung Fibrosis

    PubMed Central

    Mora, Ana L.; Torres-González, Edilson; Rojas, Mauricio; Corredor, Claudia; Ritzenthaler, Jeffrey; Xu, Jianguo; Roman, Jesse; Brigham, Kenneth; Stecenko, Arlene

    2006-01-01

    The etiology of idiopathic pulmonary fibrosis (IPF) is unknown. Because viral pathogenesis of IPF has been suggested, we have established a murine model of progressive pulmonary fibrosis by infecting IFN-γR–deficient mice (IFN-γR−/−) with the murine γ-herpesvirus 68. Because alveolar macrophages in humans with IPF have been implicated in driving the profibrotic response, we studied their role in our model. Chronic herpesvirus infection of the lung was associated with recruitment of alveolar macrophages to areas with epithelial hyperplasia and fibrosis in infected lungs. Using immunohistochemistry, Western blot, and RT-PCR techniques, we demonstrated that recruited alveolar macrophages showed high levels of expression of the proteins Ym1/2, FIZZ1 (found in inflammatory zone 1), insulin-like growth factor-1, and arginase I, and also active transcription of fibronectin, indicative of activation of macrophages by an alternative pathway. Arginase I expression was also evident in interstitial fibroblasts, and increased arginase activity was found in lungs of infected animals. Lung tissue from patients with IPF showed increased expression of arginase I in epithelial cells, fibroblast foci, and alveolar macrophages compared with normal lung. These results suggest that virus-induced upregulation of arginase I could be a mechanism driving lung fibrogenesis. PMID:16709958

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

    PubMed

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

    2004-01-20

    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 IC(50) values of 0.78 and 0.41 microM, 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 IC(50) values of 6.0 and 5.5 microM, 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

  16. 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

  17. Extensive macrophage accumulation in young and old Niemann-Pick C1 model mice involves the alternative, M2, activation pathway and inhibition of macrophage apoptosis.

    PubMed

    Deutsch, Gail; Muralidhar, Akshay; Le, Ellen; Borbon, Ivan A; Erickson, Robert P

    2016-03-10

    We have studied the pathophysiology of lung disease which occurs in two mouse models of Niemann-Pick C1 disease. We utilized Npc1(-/-) mice transgenic for normal gene expression in glia or neurons and glia at ages several fold the usual and a mouse model of the juvenile form of NPC1, a point mutation, at one age to confirm some findings. Lung weights, as per cent of body weight, increase much more than liver and spleen weights. Although pulmonary function parameters only vary for hysteresis between young and older Npc1(-/-) mice, they are markedly different than those found in normal control mice. Cholesterol accumulation continued in the older mice but sphingosine-1-phosphate was not increased. Bronchoalveolar lavage (BAL) showed a massive increase (26×) in the number of macrophages. Histologic examination from the older, transgenic Npc1(-/-) mice showed small foci of alveolar proteinosis and evidence of hemorrhage, as well as dense macrophage accumulation. A large subset of macrophages was immunopositive for Fizz1 or arginase-1, markers of the alternative activation pathway, while no Fizz1 or arginase-1 positive macrophages were found in wild-type mice. The percentage of marker positive macrophages was relatively stable at 5-10% at various ages and within the 2 transgenic models. Phosphohistone H3 and Ki67 showed low levels of proliferation of these macrophages. Apoptosis was prominent within lung capillary endothelial cells, but limited within macrophages. Thus, activation of the alternative pathway is involved in Niemann-Pick C1 associated pulmonary macrophage accumulation, with low proliferation of these cells balanced by low levels of apoptosis. PMID:26707209

  18. 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

  19. 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

  20. TFEB and TFE3 cooperate in the regulation of the innate immune response in activated macrophages.

    PubMed

    Pastore, Nunzia; Brady, Owen A; Diab, Heba I; Martina, José A; Sun, Lu; Huynh, Tuong; Lim, Jeong-A; Zare, Hossein; Raben, Nina; Ballabio, Andrea; Puertollano, Rosa

    2016-08-01

    The activation of transcription factors is critical to ensure an effective defense against pathogens. In this study we identify a critical and complementary role of the transcription factors TFEB and TFE3 in innate immune response. By using a combination of chromatin immunoprecipitation, CRISPR-Cas9-mediated genome-editing technology, and in vivo models, we determined that TFEB and TFE3 collaborate with each other in activated macrophages and microglia to promote efficient autophagy induction, increased lysosomal biogenesis, and transcriptional upregulation of numerous proinflammatory cytokines. Furthermore, secretion of key mediators of the inflammatory response (CSF2, IL1B, IL2, and IL27), macrophage differentiation (CSF1), and macrophage infiltration and migration to sites of inflammation (CCL2) was significantly reduced in TFEB and TFE3 deficient cells. These new insights provide us with a deeper understanding of the transcriptional regulation of the innate immune response. PMID:27171064

  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. 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

  3. Immunomodulatory action of monosulfated triterpene glycosides from the sea cucumber Cucumaria okhotensis: stimulation of activity of mouse peritoneal macrophages.

    PubMed

    Aminin, Dmitry L; Silchenko, Alexandra S; Avilov, Sergey A; Stepanov, Vadim G; Kalinin, Vladimir I

    2010-12-01

    Six monosulfated triterpene glycosides, frondoside A1 (1), okhotoside B1 (2), okhotoside A1-1 (3), frondoside A (4), okhotoside A2-1 (5) and cucumarioside A2-5 (6), isolated from Cucumaria okhotensis Levin et Stepanov, stimulate spreading and lysosomal activity of mouse macrophages and ROS-formation in the macrophages. The highest macrophage spreading and stimulation of their lysosomal activity was induced by glycosides 1, 4 and 6. All glycosides similarly stimulate ROS formation in macrophages, but glycoside 2 caused minimal stimulation. PMID:21299111

  4. G protein-coupled receptor160 regulates mycobacteria entry into macrophages by activating ERK.

    PubMed

    Yang, Hua; Liu, Haipeng; Chen, Hao; Mo, Haiping; Chen, Jianxia; Huang, Xiaocheng; Zheng, Ruijuan; Liu, Zhonghua; Feng, Yonghong; Liu, Feng; Ge, Baoxue

    2016-09-01

    Mycobacterium tuberculosis (Mtb), the causative agent of tuberculosis, invades and replicates within susceptible hosts by disturbing host antimicrobial mechanisms. Although G protein-coupled receptors (GPCRs) are involved in most physiological and pathological activities of mammalian cells, the roles of GPCRs in Mtb invasion into host cell remain elusive. Here, we report that GPR160 expression is elevated at both mRNA and protein level in macrophages in response to BCG infection. Both the PiggyBac (PB) transposon-mediated mutation of gpr160 gene in mouse primary macrophages and siRNA-mediated knockdown of GPR160 in the human macrophage cell line THP-1 markedly reduced the entry of green fluorescent protein (GFP) expressing BCG (BCG-GFP), also operative in vivo. BCG infection-induced phosphorylation of ERK1/2 was significantly reduced in gpr160 mutated (gpr160(-/-)) macrophages relative to levels observed in wild type macrophages, while inhibition of ERK by specific inhibitor or knockdown ERK1/2 by specific siRNA markedly reduced entry of BCG. Finally, lower bacteria burdens and attenuated pathological impairments were observed in the lungs of BCG-infected gpr160(-/-) mice. Furthermore, gpr160(-/-) macrophages also exhibits reduced uptake of Escherichia coli and Francisella tularensis. Taken together, these findings suggest an important role of GPR160 in regulating the entry of BCG into macrophages by targeting the ERK signaling pathway. As GPCRs have proven to be successful drug targets in pharmaceutical industry, it's tempting to speculate that compounds targeting GPR160, a G protein-coupled receptor, could intervene in Mtb infection. PMID:27259691

  5. Active Acoustic Monitoring of Aquatic Life.

    PubMed

    Stein, Peter J; Edson, Patrick

    2016-01-01

    Active acoustic monitoring (AAM) can be used to study the behavioral response of marine life and to mitigate harm during high-danger anthropogenic activities. This has been done in fish studies for many decades, and there are now case studies in which AAM has been used for marine mammal monitoring as well. This includes monitoring where the ranges, AAM frequency of operation, and species are such that the AAM operation is completely outside the hearing range of the animals. However, it also includes AAM operations within the hearing range of marine life, although this does not necessarily that imply AAM is not a suitable tool. It is just not always possible to have a sufficient detection and tracking range and operate at a frequency outside the marine life hearing range. Likely, the best and most important application of AAM is when the anthropogenic activity to be conducted is temporary and presents a clear danger to aquatic life. PMID:26611075

  6. Tumoricidal Effects of Macrophage-activating Immunotherapy in a Murine Model of Relapsed/ Refractory Multiple Myeloma

    PubMed Central

    Jensen, Jeffrey L.; Rakhmilevich, Alexander; Heninger, Erika; Broman, Aimee Teo; Hope, Chelsea; Phan, Funita; Miyamoto, Shigeki; Maroulakou, Ioanna; Callander, Natalie; Hematti, Peiman; Chesi, Marta; Bergsagel, P. Leif; Sondel, Paul; Asimakopoulos, Fotis

    2015-01-01

    Myeloma remains a virtually incurable malignancy. The inevitable evolution of multi-drug resistant clones and widespread clonal heterogeneity limit the potential of traditional and novel therapies to eliminate minimal residual disease, a reliable harbinger of relapse. Here we show potent anti-myeloma activity of macrophage-activating immunotherapy (αCD40+CpG) that resulted in prolongation of progression-free and overall survival in an immunocompetent, preclinically validated, transplant-based model of multi-drug resistant, relapsed/refractory myeloma (t-Vκ*MYC). αCD40+CpG was effective in vivo in the absence of cytolytic NK, T or B cells and resulted in expansion of M1-polarized (cytolytic/tumoricidal) macrophages in the bone marrow. Moreover, we show that concurrent loss/inhibition of TPL2 (Cot, MAP3K8), a MAP3K that is recruited to activated CD40 complex and regulates macrophage activation/cytokine production, potentiated direct, ex vivo anti-myeloma tumoricidal activity of αCD40+CpG-activated macrophages, promoted production of antitumor cytokine IL12 in vitro and in vivo and synergized with αCD40+CpG to further prolong progression-free and overall survival in vivo. Our results support the combination of αCD40-based macrophage activation and TPL2 inhibition for myeloma immunotherapy. We propose that αCD40-mediated activation of innate antitumor immunity may be a promising approach to control/eradicate minimal residual disease following cytoreduction with traditional or novel anti-myeloma therapies. PMID:25941352

  7. Immunostimulatory Activity of Protein Hydrolysate from Oviductus Ranae on Macrophage In Vitro

    PubMed Central

    Huang, Di; Yang, Lubing; Wang, Chenlu; Ma, Sihui; Cui, Li; Huang, Shiyang; Sheng, Xia; Weng, Qiang; Xu, Meiyu

    2014-01-01

    Oviductus Ranae is the dry oviduct of Rana chensinensis, which is also called R. chensinensis oil. Oviductus Ranae is a valuable Chinese crude drug and is recorded in the Pharmacopoeia of the People's Republic of China. The aim of this study was to investigate the immunostimulatory activity of protein hydrolysate of Oviductus Ranae (ORPH) and to assess its possible mechanism. Immunomodulatory activity of ORPH was examined in murine macrophage RAW 264.7 cells. The effect of ORPH on the phagocytic activity of macrophages was determined by the neutral red uptake assay. After treatment with ORPH, NO production levels in the culture supernatant were investigated by Griess assay. The mRNA and protein expressions of inducible nitric oxide synthase (iNOS) were detected by RT-PCR and Western blotting. The production of TNF-α, IL-1β, and IL-6 after treatment with ORPH was measured using ELISA assay. In addition, NF-κB levels were also investigated by Western blot. The results showed that ORPH enhanced the phagocytosis of macrophage, increased productions of TNF-α, IL-1β, IL-6, and NO in RAW 264.7 cells, and upregulated the mRNA and protein expression of iNOS. Besides, NF-κB, levels in RAW 264.7 cells were elevated after ORPH treatment. These findings suggested that ORPH might stimulate macrophage activities by activating the NF-κB pathway. PMID:25610475

  8. Modulation of human monocyte/macrophage activity by tocilizumab, abatacept and etanercept: An in vitro study.

    PubMed

    Obeng, Joyce Afrakoma; Amoruso, Angela; Camaschella, Gian Luca Ermanno; Sola, Daniele; Brunelleschi, Sandra; Fresu, Luigia Grazia

    2016-06-01

    Tocilizumab, etanercept and abatacept are biological drugs used in the therapy of Rheumatoid Arthritis (RA). Their mechanism of action is well documented but their direct effects on human monocytes/macrophages have not been fully investigated. The objective of this study was to evaluate in vitro the influence of these drugs on monocytes/macrophages from healthy volunteers. Human monocytes were isolated from healthy anonymous volunteers and cultured as such or differentiated to monocyte-derived macrophages (MDMs). The effect of tocilizumab, etanercept and abatacept (at concentrations similar to those in plasma of patients) on superoxide anion production, matrix metalloproteinase-9 (MMP-9) gene expression and activity, Peroxisome Proliferator-Activated Receptor (PPAR)γ expression and cell phenotype was evaluated. Exposure of monocytes/macrophages to tocilizumab, etanercept or abatacept resulted in a significant decrease of the PMA-induced superoxide anion production. Interestingly, the expression of PPARγ was significantly increased only by tocilizumab, while etanercept was the only one able to significantly reduce MMP-9 gene expression and inhibit the LPS-induced MMP-9 activity in monocytes. When etanercept and abatacept were added to the differentiating medium, both significantly reduced the amount of CD206(+)MDM. This study demonstrates that etanercept, abatacept and tocilizumab affect differently human monocytes/macrophages. In particular, the IL-6 antagonist tocilizumab seems to be more effective in inducing an anti-inflammatory phenotype of monocytes/macrophages compared to etanercept and abatacept, also in light of the up-regulation of PPARγ whose anti-inflammatory effects are well recognised. PMID:26997366

  9. Activated macrophages for treating skin ulceration: gene expression in human monocytes after hypo-osmotic shock

    PubMed Central

    FRENKEL, O; SHANI, E; BEN-BASSAT, I; BROK-SIMONI, F; ROZENFELD-GRANOT, G; KAJAKARO, G; RECHAVI, G; AMARIGLIO, N; SHINAR, E; DANON, D

    2002-01-01

    Macrophages play a major role in almost all stages of the complex process of wound healing. It has been previously shown that the incorporation of a hypo-osmotic shock step, in the process of monocyte-concentrate preparation from a blood unit, induces monocyte/macrophage activation. As the macrophages are produced using a unique, closed and sterile system, they are suitable for local application on ulcers in elderly and paraplegic patients. Enhanced phagocytosis by the activated cells, as well as increased secretion of cytokines such as IL-1, IL-6, were detected in a recent study which are in accord with the very encouraging clinical results. In the present study, we used DNA microarrays to analyse the differential gene expressions of the hypo-osmotic shock-activated monocytes/macrophages and compare them to non-treated cells. Of the genes that exhibited differences of expression in the activated cell population, 94% (68/72) displayed increased activity. The mRNA levels of 43/68 of these genes (63%) were found to be 1·5-fold or higher (1·5–7·98) in the activated macrophages cell population as compared to the non-treated cells. Only four genes were found to have lower mRNA levels in the activated cells, with ratios of expression of 0·62–0·8, which may suggest that the changes are insignificant. A significant number of the genes that showed increased levels of expression is known to be directly involved in macrophage function and wound healing. This may correlate with the increased secretion of different cytokines by the activated macrophages depicted previously. Other groups of genes expressed are known to be involved in important pathways such as neuronal growth and function, developmental defects and cancer. The hypo-osmotic shock induces a gene expression profile of cytokines and receptors in the activated cells. These may evoke potential abilities to produce a variety of protein products needed in the wound healing process and may bring to light

  10. Activating transcription factor 4 promotes angiogenesis of breast cancer through enhanced macrophage recruitment.

    PubMed

    Liu, Chen; Li, Zongjin; Wang, Lina; Tong, Lingling; He, Ningning; Chen, Yanan; Liu, Yanhua; Wu, Zhongjun; Sun, Peiqing; Xiang, Rong; Ren, Guosheng; Su, Weijun

    2015-01-01

    Angiogenesis plays an important role in the progression of tumor. Besides being regulated by tumor cells per se, tumor angiogenesis is also influenced by stromal cells in tumor microenvironment (TME), for example, tumor associated macrophages (TAMs). Activating transcription factor 4 (ATF4), a member of the ATF/CREB family, has been reported to be related to tumor angiogenesis. In this study, we found that exogenous overexpression of ATF4 in mouse breast cancer cells promotes tumor growth via increasing tumor microvascular density. However, ATF4 overexpression failed to increase the expression level of a series of proangiogenic factors including vascular endothelial growth factor A (VEGFA) in tumor cells in this model. Thus, we further investigated the infiltration of proangiogenic macrophages in tumor tissues and found that ATF4-overexpressing tumors could recruit more macrophages via secretion of macrophage colony stimulating factor (M-CSF). Overall, we concluded that exogenous overexpression of ATF4 in breast cancer cells may facilitate the recruitment of macrophages into tumor tissues and promote tumor angiogenesis and tumor growth indirectly. PMID:25883982

  11. 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

  12. [Corticosterone reception by alveolar macrophages when their functional activity has changed].

    PubMed

    Shishkina, L N; Maianskiĭ, D N; Shutko, G V; Sergeev, P V

    1985-01-01

    The binding of 3H-corticosterone by rat alveolar macrophages was studied before and after stimulation with zymosan in vivo. Thirty min after incubation of the macrophagal monolayer from intact animals with 3H-corticosterone accumulation of the hormone by the cells came to an end. As the concentration of 3H-corticosterone in the incubation medium was raised, the binding of the hormone with the saturated (receptor) system of alveolar macrophages terminated upon absorption of 10.6 fmol per 10(6) cells. Further raising of the level of the bound hormone was effected by the unsaturated (lipid) system. Stimulation with zymosan led not only to an increase in the number of the cells of the bronchoalveolar tract but also to an elevation of the intensity of 3H-corticosterone engulfment by alveolar macrophages. The number of binding sites per cell in the zymosan-activated macrophages increased 1.5-fold. This may be an important moment determining the development and liquidation of mononuclear infiltrations in the lung. PMID:3967077

  13. 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

  14. 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

  15. Class A scavenger receptor activation inhibits endoplasmic reticulum stress-induced autophagy in macrophage.

    PubMed

    Huang, Hanpeng; Li, Xiaoyu; Zhuang, Yan; Li, Nan; Zhu, Xudong; Hu, Jin; Ben, Jingjing; Yang, Qing; Bai, Hui; Chen, Qi

    2014-05-01

    Macrophage death in advanced atherosclerosis promotes plaque necrosis and destabilization. Involvement of autophagy in bulk degradation of cellular components has been recognized recently as an important mechanism for cell survival under endoplasmic reticulum (ER) stress. We previously found that the engagement of class A scavenger receptor (SR-A) triggered JNK-dependent apoptosis in ER-stressed macrophages. However, pro-apoptotic mechanisms mediated by SR-A are not fully understood. Therefore, we sought to see if SR-A mediated apoptosis was associated with autophagy in macrophages. Here, we showed that fucoidan inhibited microtubule-associated protein light chain 3-phospholipid conjugates (LC3-II) formation as well as the number of autophagosomes under ER stress. The inhibition of LC3-II formation was paralleled by the activation of the mTOR pathway, and the inhibition of mTOR allowed LC3-II induction in macrophages treated with thapsigargin plus fucoidan. Furthermore, apoptosis induced by fucoidan was prevented under ER stress by the mTOR inhibitor. We propose that fucoidan, a SR-A agonist, may contribute to macrophage apoptosis during ER stress by inhibiting autophagy. PMID:25013404

  16. 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.

  17. Biphasic effects of muramyl dipeptide or lipopolysaccharide on superoxide anion-generating activities of macrophages.

    PubMed Central

    Yagawa, K; Kaku, M; Ichinose, Y; Nagao, S; Tanaka, A; Tomoda, A

    1984-01-01

    The superoxide anion (O2-)-generating activity of guinea pig macrophages stimulated by wheat germ agglutinin (WGA), immune complexes, or phorbol myristate acetate (PMA) was studied after short- and long-term exposures of the cells to muramyl dipeptide (MDP) or lipopolysaccharide (LPS). Neither MDP nor LPS alone induced O2- release in macrophages. Short-term (30 min) exposure to these agents caused the enhanced release of O2- in response to WGA or immune complexes, though the PMA-induced O2- generation was not affected. On the other hand, long-term exposure (more than 24 h) to MDP or LPS progressively enhanced O2- generation of the cells induced by WGA, immune complexes, or even PMA. These results suggest that the mechanism for O2- generation of macrophages stimulated by WGA or immune complexes differs from that stimulated by PMA and that the differences also exist between short- and long-term exposure to MDP or LPS. PMID:6329960

  18. 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. PMID:24394850

  19. Influence of tumour condition on the macrophage activity in Candida albicans infection.

    PubMed

    Venturini, J; de Camargo, M R; Félix, M C; Vilani-Moreno, F R; de Arruda, M S P

    2009-07-01

    To better understand the interactions between opportunistic fungi and their hosts, we investigated hydrogen peroxide (H2O2), nitric oxide and TNF-alpha production by peritoneal macrophages from Ehrlich tumour-bearing mice (TBM) during microbial infections. For this purpose, TBM at days 7, 14 and 21 of tumour progression were inoculated intraperitoneally with C. albicans and evaluated after 24 and 72 h. We observed that TBM showed significant increases in H2O2, TNF-alpha levels and fungal clearance at day 7 after C. albicans infection. However, as the tumour advanced, there was a progressive decline in the release of H2O2 and TNF-alpha that was paired with the dissemination of C. albicans. These results demonstrate that protective macrophage activities against Candida albicans are limited to the initial stages of tumour growth; continued solid tumour growth weakened the macrophage response and as a consequence, weakened the host's susceptibility to opportunistic infections. PMID:19522762

  20. 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

  1. An essential regulatory role for macrophage migration inhibitory factor in T-cell activation.

    PubMed Central

    Bacher, M; Metz, C N; Calandra, T; Mayer, K; Chesney, J; Lohoff, M; Gemsa, D; Donnelly, T; Bucala, R

    1996-01-01

    The protein known as macrophage migration inhibitory factor (MIF) was one of the first cytokines to be discovered and was described 30 years ago to be a T-cell-derived factor that inhibited the random migration of macrophages in vitro. A much broader role for MIF has emerged recently as a result of studies that have demonstrated it to be released from the anterior pituitary gland in vivo. MIF also is the first protein that has been identified to be secreted from monocytes/macrophages upon glucocorticoid stimulation. Once released, MIF acts to "override" or counter-regulate the suppressive effects of glucocorticoids on macrophage cytokine production. We report herein that MIF plays an important regulatory role in the activation of T cells induced by mitogenic or antigenic stimuli. Activated T cells produce MIF and neutralizing anti-MIF antibodies inhibit T-cell proliferation and interleukin 2 production in vitro, and suppress antigen-driven T-cell activation and antibody production in vivo. T cells also release MIF in response to glucocorticoid stimulation and MIF acts to override glucocorticoid inhibition of T-cell proliferation and interleukin 2 and interferon gamma production. These studies indicate that MIF acts in concert with glucocorticoids to control T-cell activation and assign a previously unsuspected but critical role for MIF in antigen-specific immune responses. Images Fig. 1 Fig. 2 Fig. 3 Fig. 4 PMID:8755565

  2. Modular analysis of bioinformatics demonstrates a critical role for NF-κB in macrophage activation.

    PubMed

    Zhang, Yingmei; Wang, Yingmei; Lu, Ming; Qiao, Xin; Sun, Bei; Zhang, Weihui; Xue, Dongbo

    2014-08-01

    To achieve the goal of identifying the gene groups that regulated macrophage activation, a total of 925 differentially expressed genes of activated macrophages were found at the intersection of the three series (GSE5099-1, GSE5099-2, and GSE18686) from the Gene Expression Omnibus (GEO) database, and a sub-network was constructed based on the protein-protein interaction (PPI) network. Four communities (K = 3) were identified from the sub-network using the CFinder software. Community 1 was considered as the gene group of interest base on the heat map. GO-BP and KEGG enrichment analysis with the DAVID software showed that the functions of the 14 genes in community 1 were mainly related to the NF-κB pathway. A network was constructed using the Cytoscape software. The diagram showed that STAT1, NFKBIA, NFKAIB, JUN, and RELA were the key genes in the regulation of macrophage activation. Among these genes, RELA (NF-κB P65) was an important member of the NF-κB family, while NFKBIA (IκBα) and NFKAIB (IκBβ) were the inhibitory factors of NF-κB. Small molecules capable of regulating these five genes were identified via the CMap software, and a network diagram was generated using the Cytoscape software to provide a reference for the development of new drugs that regulate macrophage activation. PMID:24577727

  3. 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.

  4. 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 results indicated that in pediatric non-alcoholic fatty liver disease, pro-inflammatory macrophages were the predominant subset. Macrophage polarization was correlated with Non-alcoholic fatty liver disease Activity Score, ductular reaction, and portal fibrosis; docosahexaenoic acid treatment determined a macrophage polarization towards an anti-inflammatory phenotype in correlation with the reduction of serum inflammatory cytokines, with increased macrophage apoptosis, and with the up-regulation of macrophage Wnt3a expression; macrophage Wnt3a expression was correlated with β-catenin phosphorylation in hepatic progenitor cells and signs of commitment towards hepatocyte fate. In conclusion, macrophage polarization seems to have a key role in the progression of pediatric non-alcoholic fatty liver disease; the modulation of macrophage polarization could drive hepatic progenitor cell response by Wnt3a production. PMID:27310371

  5. Macrophage activation associated with chronic murine cytomegalovirus infection results in more severe experimental choroidal neovascularization.

    PubMed

    Cousins, Scott W; Espinosa-Heidmann, Diego G; Miller, Daniel M; Pereira-Simon, Simone; Hernandez, Eleut P; Chien, Hsin; Meier-Jewett, Courtney; Dix, Richard D

    2012-01-01

    The neovascular (wet) form of age-related macular degeneration (AMD) leads to vision loss due to choroidal neovascularization (CNV). Since macrophages are important in CNV development, and cytomegalovirus (CMV)-specific IgG serum titers in patients with wet AMD are elevated, we hypothesized that chronic CMV infection contributes to wet AMD, possibly by pro-angiogenic macrophage activation. This hypothesis was tested using an established mouse model of experimental CNV. At 6 days, 6 weeks, or 12 weeks after infection with murine CMV (MCMV), laser-induced CNV was performed, and CNV severity was determined 4 weeks later by analysis of choroidal flatmounts. Although all MCMV-infected mice exhibited more severe CNV when compared with control mice, the most severe CNV developed in mice with chronic infection, a time when MCMV-specific gene sequences could not be detected within choroidal tissues. Splenic macrophages collected from mice with chronic MCMV infection, however, expressed significantly greater levels of TNF-α, COX-2, MMP-9, and, most significantly, VEGF transcripts by quantitative RT-PCR assay when compared to splenic macrophages from control mice. Direct MCMV infection of monolayers of IC-21 mouse macrophages confirmed significant stimulation of VEGF mRNA and VEGF protein as determined by quantitative RT-PCR assay, ELISA, and immunostaining. Stimulation of VEGF production in vivo and in vitro was sensitive to the antiviral ganciclovir. These studies suggest that chronic CMV infection may serve as a heretofore unrecognized risk factor in the pathogenesis of wet AMD. One mechanism by which chronic CMV infection might promote increased CNV severity is via stimulation of macrophages to make pro-angiogenic factors (VEGF), an outcome that requires active virus replication. PMID:22570607

  6. Macrophage Activation Associated with Chronic Murine Cytomegalovirus Infection Results in More Severe Experimental Choroidal Neovascularization

    PubMed Central

    Cousins, Scott W.; Espinosa-Heidmann, Diego G.; Miller, Daniel M.; Pereira-Simon, Simone; Hernandez, Eleut P.; Chien, Hsin; Meier-Jewett, Courtney; Dix, Richard D.

    2012-01-01

    The neovascular (wet) form of age-related macular degeneration (AMD) leads to vision loss due to choroidal neovascularization (CNV). Since macrophages are important in CNV development, and cytomegalovirus (CMV)-specific IgG serum titers in patients with wet AMD are elevated, we hypothesized that chronic CMV infection contributes to wet AMD, possibly by pro-angiogenic macrophage activation. This hypothesis was tested using an established mouse model of experimental CNV. At 6 days, 6 weeks, or 12 weeks after infection with murine CMV (MCMV), laser-induced CNV was performed, and CNV severity was determined 4 weeks later by analysis of choroidal flatmounts. Although all MCMV-infected mice exhibited more severe CNV when compared with control mice, the most severe CNV developed in mice with chronic infection, a time when MCMV-specific gene sequences could not be detected within choroidal tissues. Splenic macrophages collected from mice with chronic MCMV infection, however, expressed significantly greater levels of TNF-α, COX-2, MMP-9, and, most significantly, VEGF transcripts by quantitative RT-PCR assay when compared to splenic macrophages from control mice. Direct MCMV infection of monolayers of IC-21 mouse macrophages confirmed significant stimulation of VEGF mRNA and VEGF protein as determined by quantitative RT-PCR assay, ELISA, and immunostaining. Stimulation of VEGF production in vivo and in vitro was sensitive to the antiviral ganciclovir. These studies suggest that chronic CMV infection may serve as a heretofore unrecognized risk factor in the pathogenesis of wet AMD. One mechanism by which chronic CMV infection might promote increased CNV severity is via stimulation of macrophages to make pro-angiogenic factors (VEGF), an outcome that requires active virus replication. PMID:22570607

  7. Regulation of skeletal muscle regeneration by CCR2-activating chemokines is directly related to macrophage recruitment

    PubMed Central

    Martinez, Carlo O.; McHale, Matthew J.; Wells, Jason T.; Ochoa, Oscar; Michalek, Joel E.; McManus, Linda M.

    2010-01-01

    Muscle regeneration requires CC chemokine receptor 2 (CCR2) expression on bone marrow-derived cells; macrophages are a prominent CCR2-expressing cell in this process. CCR2−/− mice have severe impairments in angiogenesis, macrophage recruitment, and skeletal muscle regeneration following cardiotoxin (CTX)-induced injury. However, multiple chemokines activate CCR2, including monocyte chemotactic proteins (MCP)-1, -3, and -5. We hypothesized that MCP-1 is the chemokine ligand that mediates the impairments present in CCR2−/− mice. We examined muscle regeneration, capillary density, and cellular recruitment in MCP-1−/− and CCR2−/− mice following injury. Muscle regeneration and adipocyte accumulation, but not capillary density, were significantly impaired in MCP-1−/− compared with wild-type (WT) mice; however, muscle regeneration and adipocyte accumulation impairments were not as severe as observed in CCR2−/− mice. Although tissue levels of MCP-5 were elevated in MCP-1−/− mice compared with WT, the administration of MCP-5 neutralizing antibody did not alter muscle regeneration in MCP-1−/− mice. While neutrophil accumulation after injury was similar in all three mouse strains, macrophage recruitment was highest in WT mice, intermediate in MCP-1−/− mice, and severely impaired in CCR2−/− mice. In conclusion, while the absence of MCP-1 resulted in impaired macrophage recruitment and muscle regeneration, MCP-1−/− mice exhibit an intermediate phenotype compared with CCR2−/− mice. Intermediate macrophage recruitment in MCP-1−/− mice was associated with similar capillary density to WT, suggesting that fewer macrophages may be needed to restore angiogenesis vs. muscle regeneration. Finally, other chemokines, in addition to MCP-1 and MCP-5, may activate CCR2-dependent regenerative processes resulting in an intermediate phenotype in MCP-1−/− mice. PMID:20631294

  8. Regulation of skeletal muscle regeneration by CCR2-activating chemokines is directly related to macrophage recruitment.

    PubMed

    Martinez, Carlo O; McHale, Matthew J; Wells, Jason T; Ochoa, Oscar; Michalek, Joel E; McManus, Linda M; Shireman, Paula K

    2010-09-01

    Muscle regeneration requires CC chemokine receptor 2 (CCR2) expression on bone marrow-derived cells; macrophages are a prominent CCR2-expressing cell in this process. CCR2-/- mice have severe impairments in angiogenesis, macrophage recruitment, and skeletal muscle regeneration following cardiotoxin (CTX)-induced injury. However, multiple chemokines activate CCR2, including monocyte chemotactic proteins (MCP)-1, -3, and -5. We hypothesized that MCP-1 is the chemokine ligand that mediates the impairments present in CCR2-/- mice. We examined muscle regeneration, capillary density, and cellular recruitment in MCP-1-/- and CCR2-/- mice following injury. Muscle regeneration and adipocyte accumulation, but not capillary density, were significantly impaired in MCP-1-/- compared with wild-type (WT) mice; however, muscle regeneration and adipocyte accumulation impairments were not as severe as observed in CCR2-/- mice. Although tissue levels of MCP-5 were elevated in MCP-1-/- mice compared with WT, the administration of MCP-5 neutralizing antibody did not alter muscle regeneration in MCP-1-/- mice. While neutrophil accumulation after injury was similar in all three mouse strains, macrophage recruitment was highest in WT mice, intermediate in MCP-1-/- mice, and severely impaired in CCR2-/- mice. In conclusion, while the absence of MCP-1 resulted in impaired macrophage recruitment and muscle regeneration, MCP-1-/- mice exhibit an intermediate phenotype compared with CCR2-/- mice. Intermediate macrophage recruitment in MCP-1-/- mice was associated with similar capillary density to WT, suggesting that fewer macrophages may be needed to restore angiogenesis vs. muscle regeneration. Finally, other chemokines, in addition to MCP-1 and MCP-5, may activate CCR2-dependent regenerative processes resulting in an intermediate phenotype in MCP-1-/- mice. PMID:20631294

  9. Interaction of Mycoplasma gallisepticum with Chicken Tracheal Epithelial Cells Contributes to Macrophage Chemotaxis and Activation

    PubMed Central

    Majumder, Sanjukta

    2015-01-01

    Mycoplasma gallisepticum colonizes the chicken respiratory mucosa and mediates a severe inflammatory response hallmarked by subepithelial leukocyte infiltration. We recently reported that the interaction of M. gallisepticum with chicken tracheal epithelial cells (TECs) mediated the upregulation of chemokine and inflammatory cytokine genes in these cells (S. Majumder, F. Zappulla, and L. K. Silbart, PLoS One 9:e112796, http://dx.doi.org/10.1371/journal.pone.0112796). The current study extends these observations and sheds light on how this initial interaction may give rise to subsequent inflammatory events. Conditioned medium from TECs exposed to the virulent Rlow strain induced macrophage chemotaxis to a much higher degree than the nonvirulent Rhigh strain. Coculture of chicken macrophages (HD-11) with TECs exposed to live mycoplasma revealed the upregulation of several proinflammatory genes associated with macrophage activation, including interleukin-1β (IL-1β), IL-6, IL-8, CCL20, macrophage inflammatory protein 1β (MIP-1β), CXCL-13, and RANTES. The upregulation of these genes was similar to that observed upon direct contact of HD-11 cells with live M. gallisepticum. Coculture of macrophages with Rlow-exposed TECs also resulted in prolonged expression of chemokine genes, such as those encoding CXCL-13, MIP-1β, RANTES, and IL-8. Taken together, these studies support the notion that the initial interaction of M. gallisepticum with host respiratory epithelial cells contributes to macrophage chemotaxis and activation by virtue of robust upregulation of inflammatory cytokine and chemokine genes, thereby setting the stage for chronic tissue inflammation. PMID:26527215

  10. Interaction of Mycoplasma gallisepticum with Chicken Tracheal Epithelial Cells Contributes to Macrophage Chemotaxis and Activation.

    PubMed

    Majumder, Sanjukta; Silbart, Lawrence K

    2016-01-01

    Mycoplasma gallisepticum colonizes the chicken respiratory mucosa and mediates a severe inflammatory response hallmarked by subepithelial leukocyte infiltration. We recently reported that the interaction of M. gallisepticum with chicken tracheal epithelial cells (TECs) mediated the upregulation of chemokine and inflammatory cytokine genes in these cells (S. Majumder, F. Zappulla, and L. K. Silbart, PLoS One 9:e112796, http://dx.doi.org/10.1371/journal.pone.0112796). The current study extends these observations and sheds light on how this initial interaction may give rise to subsequent inflammatory events. Conditioned medium from TECs exposed to the virulent Rlow strain induced macrophage chemotaxis to a much higher degree than the nonvirulent Rhigh strain. Coculture of chicken macrophages (HD-11) with TECs exposed to live mycoplasma revealed the upregulation of several proinflammatory genes associated with macrophage activation, including interleukin-1β (IL-1β), IL-6, IL-8, CCL20, macrophage inflammatory protein 1β (MIP-1β), CXCL-13, and RANTES. The upregulation of these genes was similar to that observed upon direct contact of HD-11 cells with live M. gallisepticum. Coculture of macrophages with Rlow-exposed TECs also resulted in prolonged expression of chemokine genes, such as those encoding CXCL-13, MIP-1β, RANTES, and IL-8. Taken together, these studies support the notion that the initial interaction of M. gallisepticum with host respiratory epithelial cells contributes to macrophage chemotaxis and activation by virtue of robust upregulation of inflammatory cytokine and chemokine genes, thereby setting the stage for chronic tissue inflammation. PMID:26527215

  11. Differential activation of inflammatory pathways in testicular macrophages provides a rationale for their subdued inflammatory capacity.

    PubMed

    Bhushan, Sudhanshu; Tchatalbachev, Svetlin; Lu, Yongning; Fröhlich, Suada; Fijak, Monika; Vijayan, Vijith; Chakraborty, Trinad; Meinhardt, Andreas

    2015-06-01

    Spermatogenic cells express cell-specific molecules with the potential to be seen as "foreign" by the immune system. Owing to the time difference between their appearance in puberty and the editing of the lymphocyte repertoire around birth, local adaptations of the immune system coined immune privilege are required to confer protection from autoattack. Testicular macrophages (TM) play an important role in maintaining testicular immune privilege and display reduced proinflammatory capacity compared with other macrophages. However, the molecular mechanism underlying this macrophage phenotype remained elusive. We demonstrate that TM have a lower constitutive expression of TLR pathway-specific genes compared with peritoneal macrophages. Moreover, in TM stimulated with LPS, the NF-κB signaling pathway is blocked due to lack of IκBα ubiquitination and, hence, degradation. Instead, challenge of TM with LPS or polyinosinic-polycytidylic acid induces MAPK, AP-1, and CREB signaling pathways, which leads to production of proinflammatory cytokines such as TNF-α, although at much lower levels than in peritoneal macrophages. Pretreatment of TM with inhibitors for MAPKs p38 and ERK1/2 suppresses activation of AP-1 and CREB signaling pathways and attenuates LPS-induced TNF-α and IL-10 secretion. High levels of IL-10 production and activation of STAT3 by LPS stimulation in TM indicate a regulatory macrophage phenotype. Our results suggest that TM maintain testicular immune privilege by inhibiting NF-κB signaling through impairment of IκBα ubiquitination and a general reduction of TLR cascade gene expression. However, TM do maintain some capacity for innate immune responses through AP-1 and CREB signaling pathways. PMID:25917085

  12. [Phagocytosis of Mycobacterium leprae down-regulates anti-microbial activity of murine macrophages against Mycobacterium intracellulare].

    PubMed

    Tatano, Yutaka; Sano, Chiaki; Emori, Masako; Saito, Hajime; Sato, Katsumasa; Shimizu, Toshiaki; Tomioka, Haruaki

    2012-09-01

    Patients with highly bacillated lepromatous leprosy (LL) essentially lack T cell-mediated immune responses specific to Mycobacterium leprae (ML) antigens, resulting in severely impaired host resistance to leprosy bacilli. Such type of immune unresponsiveness characteristic of LL patients is mainly attributable to markedly depressed T cell ability to activate/expand in response to ML antigens. In this study, we examined profiles of antimycobacterial activity of macrophages, which phagocytized leprosy bacilli, because there is another possibility that, in LL patients, host macrophages in the leprosy lesions are impaired in their antimicrobial activity due to their interaction with infected leprosy bacilli, particularly cellular events through binding with and/or internalization of the pathogens, thereby causing the reduction in host resistance to ML pathogens. The present study indicated the following. First, the anti-M. avium complex activity of murine peritoneal macrophages was significantly reduced when they had phagocytosed heat-killed leprosy bacilli. Second, infection of macrophages with leprosy bacilli did not affect macrophage-mediated suppressor activity against T cell proliferative response to Concanavalin A. These findings indicate that macrophage's intracellular signaling pathways that are up-regulated in response to phagocytosis of leprosy bacilli are linked to the signaling cascades participating in macrophage antimicrobial functions, but not cross-talk with those allowing the expression of macrophage's suppressor activity against T cell functions. PMID:23012845

  13. Triple trouble--macrophage activation syndrome in a case of severe leptospirosis and scrub typhus co-infection.

    PubMed

    Diwan, A G; Shewale, Rahul; Iyer, Shivakumar; Nisal, Amit; Agrawa, Prakhar

    2014-01-01

    Macrophage activation syndrome is a potentially life threatening phenomenon characterised by aggressive proliferation of macrophages and T lymphocytes leading to haemophagocytosis of other blood cells and multi organ failure. Here we present a very unusual combination of leptospirosis and scrub typhus infection leading to macrophage activation syndrome. Scrub typhus associated with macrophage activation syndrome has rarely been reported in India. A 40 year old female presented with high grade fever, seizures, bodyache, arthralgia and severe breathlessness. Investigations revealed persistent thrombocytopenia, impaired liver function tests, renal dysfunction, leptospiral IgM ELISA positive and a positive Weil Felix test. There was evidence of haemophagocytosis in bone marrow. Macrophage activation syndrome if left untreated has been associated with rapidly fatal outcome and early treatment can help us save that one precious thing..called life..! PMID:25327097

  14. Reactive oxygen species in the tumor niche triggers altered activation of macrophages and immunosuppression: Role of fluoxetine.

    PubMed

    Ghosh, Sayan; Mukherjee, Sudeshna; Choudhury, Sreetama; Gupta, Payal; Adhikary, Arghya; Baral, Rathindranath; Chattopadhyay, Sreya

    2015-07-01

    Macrophages are projected as one of the key players responsible for the progression of cancer. Classically activated (M1) macrophages are pro-inflammatory and have a central role in host defense, while alternatively activated (M2) macrophages are associated with immunosuppression. Macrophages residing at the site of neoplastic growth are alternately activated and are referred to as tumor-associated macrophages (TAMs). These "cooperate" with tumor tissue, promoting increased proliferation and immune escape. Selective serotonin reuptake inhibitors like fluoxetine have recently been reported to possess anti-inflammatory activity. We used fluoxetine to target tumor-associated inflammation and consequent alternate polarization of macrophages. We established that murine peritoneal macrophages progressed towards an altered activation state when exposed to cell-free tumor fluid, as evidenced by increased IL-6, IL-4 and IL-10 levels. These polarized macrophages showed significant pro-oxidant bias and increased p65 nuclear localization. It was further observed that these altered macrophages could induce oxidative insult and apoptosis in cultured mouse CD3(+) T cells. To validate these findings, we replicated key experiments in vivo, and observed that there was increased serum IL-6, IL-4 and IL-10 in tumor-bearing animals, with increased % CD206(+) cells within the tumor niche. TAMs showed increased nuclear localization of p65 with decreased Nrf2 expression in the nucleus. These results were associated with increase in apoptosis of CD3(+) T cells co-cultured with TAM-spent media. We could establish that fluoxetine treatment could specifically re-educate the macrophages both in vitro and in vivo by skewing their phenotype such that immune suppression mediated by tumor-dictated macrophages was successfully mitigated. PMID:25819340

  15. miR-155 targets Caspase-3 mRNA in activated macrophages.

    PubMed

    De Santis, Rebecca; Liepelt, Anke; Mossanen, Jana C; Dueck, Anne; Simons, Nadine; Mohs, Antje; Trautwein, Christian; Meister, Gunter; Marx, Gernot; Ostareck-Lederer, Antje; Ostareck, Dirk H

    2016-01-01

    To secure the functionality of activated macrophages in the innate immune response, efficient life span control is required. Recognition of bacterial lipopolysaccharides (LPS) by toll-like receptor 4 (TLR4) induces downstream signaling pathways, which merge to induce the expression of cytokine genes and anti-apoptotic genes. MicroRNAs (miRNAs) have emerged as important inflammatory response modulators, but information about their functional impact on apoptosis is scarce. To identify miRNAs differentially expressed in response to LPS, cDNA libraries from untreated and LPS-activated murine macrophages were analyzed by deep sequencing and regulated miRNA expression was verified by Northern blotting and qPCR. Employing TargetScan(TM) we identified CASPASE-3 (CASP-3) mRNA that encodes a key player in apoptosis as potential target of LPS-induced miR-155. LPS-dependent primary macrophage activation revealed TLR4-mediated enhancement of miR-155 expression and CASP-3 mRNA reduction. Endogenous CASP-3 and cleaved CASP-3 protein declined in LPS-activated macrophages. Accumulation of miR-155 and CASP-3 mRNA in miRNA-induced silencing complexes (miRISC) was demonstrated by ARGONAUTE 2 (AGO2) immunoprecipitation. Importantly, specific antagomir transfection effectively reduced mature miR-155 and resulted in significantly elevated CASP-3 mRNA levels in activated macrophages. In vitro translation assays demonstrated that the target site in the CASP-3 mRNA 3'UTR mediates miR-155-dependent Luciferase reporter mRNA destabilization. Strikingly, Annexin V staining of macrophages transfected with antagomir-155 and stimulated with LPS prior to staurosporine (SSP) treatment implied that LPS-induced miR-155 prevents apoptosis through CASP-3 mRNA down-regulation. In conclusion, we report that miR-155-mediated CASP-3 mRNA destabilization in LPS-activated RAW 264.7 macrophages suppresses apoptosis, as a prerequisite to maintain their crucial function in inflammation. PMID:26574931

  16. Resistance of LPS-activated bone marrow derived macrophages to apoptosis mediated by dexamethasone

    PubMed Central

    Haim, Yasmin Ohana; Unger, Naamit Deshet; Souroujon, Miriam C.; Mittelman, Moshe; Neumann, Drorit

    2014-01-01

    Glucocorticoids (GC) display pleiotropic effects on the immune system. Macrophages are a major target for GC action. Here we show that dexamethasone (DEX), a synthetic GC, decreased viability of naïve bone marrow-derived macrophages (BMDM), involving an apoptotic mechanism. Administration of DEX together with lipopolysaccharide (LPS) protected BMDM against DEX-mediated cell death, suggesting that activated BMDM respond to DEX differently than naïve BMDM. An insight to the molecular basis of LPS actions was provided by a 7 fold increase in mRNA levels of glucocorticoid receptor beta (GRβ), a GR dominant-negative splice variant which inhibits GRα's transcriptional activity. LPS did not inhibit all DEX-mediated effects on BMDM; DEX significantly reduced the percentage of BMDM expressing high levels of the cell surface markers F4/80 and CD11b and led to a decrease in macrophage inflammatory protein 1 alpha (MIP1-α) mRNA and protein levels. These two DEX-mediated effects were not prevented by LPS. Our finding that LPS did not reduce the DEX-induced elevation of glucocorticoid-induced leucine zipper (GILZ), a mediator of GCs anti-inflammatory actions, may provide an underlying mechanism. These findings enable a better understanding of clinical states, such as sepsis, in which macrophages are activated by endotoxins and treatment by GCs is considered. PMID:24608810

  17. Virulent Mycobacterium bovis Beijing Strain Activates the NLRP7 Inflammasome in THP-1 Macrophages

    PubMed Central

    Zhou, Yang; Shah, Syed Zahid Ali; Yang, Lifeng; Zhang, Zhongqiu; Zhou, Xiangmei; Zhao, Deming

    2016-01-01

    Mycobacterium bovis is the causative agent of tuberculosis in a wide range of mammals, including humans. Macrophages are the first line of host defense. They secrete proinflammatory cytokines, such as interleukin-1 beta (IL-1β), in response to mycobacterial infection, but the underlying mechanisms by which human macrophages are activated and release IL-1β following M. bovis infection are poorly understood. Here we show that the ‘nucleotide binding and oligomerization of domain-like receptor (NLR) family pyrin domain containing 7 protein’ (NLRP7) inflammasome is involved in IL-1β secretion and caspase-1 activation induced by M. bovis infection in THP-1 macrophages. NLRP7 inflammasome activation promotes the induction of pyroptosis as well as the expression of tumor necrosis factor alpha (TNF-α), Chemokine (C-C motif) ligand 3 (CCL3) and IL-1β mRNAs. Thus, the NLRP7 inflammasome contributes to IL-1β secretion and induction of pyroptosis in response to M. bovis infection in THP-1 macrophages. PMID:27043315

  18. beta-Lapachone reduces endotoxin-induced macrophage activation and lung edema and mortality.

    PubMed

    Tzeng, Huei-Ping; Ho, Feng-Ming; Chao, Kuo-Fang; Kuo, Min-Liang; Lin-Shiau, Shoei-Yn; Liu, Shing-Hwa

    2003-07-01

    beta-Lapachone, a 1,2-naphthoquinone, is a novel chemotherapeutic agent. It has been shown to be capable of suppressing inducible nitric oxide synthase expression and function in rat alveolar macrophages. The authors further performed experiments to examine the molecular mechanism of beta-lapachone on LPS-induced responses in rat alveolar macrophages and to evaluate its in vivo antiinflammatory effect. A significant increase in nitrite production and inducible nitric oxide synthase expression was elicited in macrophages treated with LPS that was inhibited by coincubation with beta-lapachone. beta-Lapachone could also inhibit the production of tumor necrosis factor-alpha induced by LPS. LPS induces protein tyrosine phosphorylation and nuclear factor-kappaB binding activity by gel mobility shift assay in macrophages. These events were significantly inhibited by beta-lapachone. Furthermore, beta-lapachone in vivo protected against the induction of lung edema, lung-inducible nitric oxide synthase protein expression and nuclear factor-kappaB activation, lethality, and increased plasma nitrite and serum tumor necrosis factor-alpha levels induced by LPS. These results indicate that beta-lapachone suppresses inducible nitric oxide synthase induction and tumor necrosis factor-alpha production mediated by the inhibition of protein tyrosine phosphorylation and nuclear factor-kappaB activation caused by LPS. This results in a beneficial effect in an animal model of sepsis. PMID:12724123

  19. Redefining the transcriptional regulatory dynamics of classically and alternatively activated macrophages by deepCAGE transcriptomics

    PubMed Central

    Roy, Sugata; Schmeier, Sebastian; Arner, Erik; Alam, Tanvir; Parihar, Suraj P.; Ozturk, Mumin; Tamgue, Ousman; Kawaji, Hideya; de Hoon, Michiel J. L.; Itoh, Masayoshi; Lassmann, Timo; Carninci, Piero; Hayashizaki, Yoshihide; Forrest, Alistair R. R.; Bajic, Vladimir B.; Guler, Reto; Consortium, FANTOM; Brombacher, Frank; Suzuki, Harukazu

    2015-01-01

    Classically or alternatively activated macrophages (M1 and M2, respectively) play distinct and important roles for microbiocidal activity, regulation of inflammation and tissue homeostasis. Despite this, their transcriptional regulatory dynamics are poorly understood. Using promoter-level expression profiling by non-biased deepCAGE we have studied the transcriptional dynamics of classically and alternatively activated macrophages. Transcription factor (TF) binding motif activity analysis revealed four motifs, NFKB1_REL_RELA, IRF1,2, IRF7 and TBP that are commonly activated but have distinct activity dynamics in M1 and M2 activation. We observe matching changes in the expression profiles of the corresponding TFs and show that only a restricted set of TFs change expression. There is an overall drastic and transient up-regulation in M1 and a weaker and more sustainable up-regulation in M2. Novel TFs, such as Thap6, Maff, (M1) and Hivep1, Nfil3, Prdm1, (M2) among others, were suggested to be involved in the activation processes. Additionally, 52 (M1) and 67 (M2) novel differentially expressed genes and, for the first time, several differentially expressed long non-coding RNA (lncRNA) transcriptome markers were identified. In conclusion, the finding of novel motifs, TFs and protein-coding and lncRNA genes is an important step forward to fully understand the transcriptional machinery of macrophage activation. PMID:26117544

  20. Cleavage of Type I Collagen by Fibroblast Activation Protein-α Enhances Class A Scavenger Receptor Mediated Macrophage Adhesion

    PubMed Central

    Mazur, Anna; Holthoff, Emily; Vadali, Shanthi; Kelly, Thomas; Post, Steven R.

    2016-01-01

    Pathophysiological conditions such as fibrosis, inflammation, and tumor progression are associated with modification of the extracellular matrix (ECM). These modifications create ligands that differentially interact with cells to promote responses that drive pathological processes. Within the tumor stroma, fibroblasts are activated and increase the expression of type I collagen. In addition, activated fibroblasts specifically express fibroblast activation protein-α (FAP), a post-prolyl peptidase. Although FAP reportedly cleaves type I collagen and contributes to tumor progression, the specific pathophysiologic role of FAP is not clear. In this study, the possibility that FAP-mediated cleavage of type I collagen modulates macrophage interaction with collagen was examined using macrophage adhesion assays. Our results demonstrate that FAP selectively cleaves type I collagen resulting in increased macrophage adhesion. Increased macrophage adhesion to FAP-cleaved collagen was not affected by inhibiting integrin-mediated interactions, but was abolished in macrophages lacking the class A scavenger receptor (SR-A/CD204). Further, SR-A expressing macrophages localize with activated fibroblasts in breast tumors of MMTV-PyMT mice. Together, these results demonstrate that FAP-cleaved collagen is a substrate for SR-A-dependent macrophage adhesion, and suggest that by modifying the ECM, FAP plays a novel role in mediating communication between activated fibroblasts and macrophages. PMID:26934296

  1. Histone deacetylases in monocyte/macrophage development, activation and metabolism: refining HDAC targets for inflammatory and infectious diseases

    PubMed Central

    Das Gupta, Kaustav; Shakespear, Melanie R; Iyer, Abishek; Fairlie, David P; Sweet, Matthew J

    2016-01-01

    Macrophages have central roles in danger detection, inflammation and host defense, and consequently, these cells are intimately linked to most disease processes. Major advances in our understanding of the development and function of macrophages have recently come to light. For example, it is now clear that tissue-resident macrophages can be derived from either blood monocytes or through local proliferation of phagocytes that are originally seeded during embryonic development. Metabolic state has also emerged as a major control point for macrophage activation phenotypes. Herein, we review recent literature linking the histone deacetylase (HDAC) family of enzymes to macrophage development and activation, particularly in relation to these recent developments. There has been considerable interest in potential therapeutic applications for small molecule inhibitors of HDACs (HDACi), not only for cancer, but also for inflammatory and infectious diseases. However, the enormous range of molecular and cellular processes that are controlled by different HDAC enzymes presents a potential stumbling block to clinical development. We therefore present examples of how classical HDACs control macrophage functions, roles of specific HDACs in these processes and approaches for selective targeting of drugs, such as HDACi, to macrophages. Development of selective inhibitors of macrophage-expressed HDACs and/or selective delivery of pan HDACi to macrophages may provide avenues for enhancing efficacy of HDACi in therapeutic applications, while limiting unwanted side effects. PMID:26900475

  2. Transcriptomic Analysis of Human Polarized Macrophages: More than One Role of Alternative Activation?

    PubMed Central

    Derlindati, Eleonora; Dei Cas, Alessandra; Montanini, Barbara; Spigoni, Valentina; Curella, Valentina; Aldigeri, Raffaella; Ardigò, Diego; Zavaroni, Ivana; Bonadonna, Riccardo C.

    2015-01-01

    Background Macrophages are a heterogeneous cell population which in response to the cytokine milieu polarize in either classically activated macrophages (M1) or alternatively activated macrophages (M2). This plasticity makes macrophages essential in regulating inflammation, immune response and tissue remodeling and a novel therapeutic target in inflammatory diseases such as atherosclerosis. The aim of the study was to describe the transcriptomic profiles of differently polarized human macrophages to generate new hypotheses on the biological function of the different macrophage subtypes. Methods and Results Polarization of circulating monocytes/macrophages of blood donors was induced in vitro by IFN-γ and LPS (M1), by IL-4 (M2a), and by IL-10 (M2c). Unstimulated cells (RM) served as time controls. Gene expression profile of M1, M2a, M2c and RM was assessed at 6, 12 and 24h after polarization with Whole Human Genome Agilent Microarray technique. When compared to RM, M1 significantly upregulated pathways involved in immunity and inflammation, whereas M2a did the opposite. Conversely, decreased and increased expression of mitochondrial metabolism, consistent with insulin resistant and insulin sensitive patterns, was seen in M1 and M2a, respectively. The time sequence in the expression of some pathways appeared to have some specific bearing on M1 function. Finally, canonical and non-canonical Wnt genes and gene groups, promoting inflammation and tissue remodeling, were upregulated in M2a compared to RM. Conclusion Our data in in vitro polarized human macrophages: 1. confirm and extend known inflammatory and anti-inflammatory gene expression patterns; 2. demonstrate changes in mitochondrial metabolism associated to insulin resistance and insulin sensitivity in M1 and M2a, respectively; 3. highlight the potential relevance of gene expression timing in M1 function; 4. unveil enhanced expression of Wnt pathways in M2a suggesting a potential dual (pro-inflammatory and anti

  3. 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

  4. Opposite cross-talk by oleate and palmitate on insulin signaling in hepatocytes through macrophage activation.

    PubMed

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

    2015-05-01

    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

  5. Immunotherapy for Prostate Cancer with Gc Protein-Derived Macrophage-Activating Factor, GcMAF.

    PubMed

    Yamamoto, Nobuto; Suyama, Hirofumi; Yamamoto, Nobuyuki

    2008-07-01

    Serum Gc protein (known as vitamin D(3)-binding protein) is the precursor for the principal macrophage-activating factor (MAF). The MAF precursor activity of serum Gc protein of prostate cancer patients was lost or reduced because Gc protein was deglycosylated by serum alpha-N-acetylgalactosaminidase (Nagalase) secreted from cancerous cells. Therefore, macrophages of prostate cancer patients having deglycosylated Gc protein cannot be activated, leading to immunosuppression. Stepwise treatment of purified Gc protein with immobilized beta-galactosidase and sialidase generated the most potent MAF (termed GcMAF) ever discovered, which produces no adverse effect in humans. Macrophages activated by GcMAF develop a considerable variation of receptors that recognize the abnormality in malignant cell surface and are highly tumoricidal. Sixteen nonanemic prostate cancer patients received weekly administration of 100 ng of GcMAF. As the MAF precursor activity increased, their serum Nagalase activity decreased. Because serum Nagalase activity is proportional to tumor burden, the entire time course analysis for GcMAF therapy was monitored by measuring the serum Nagalase activity. After 14 to 25 weekly administrations of GcMAF (100 ng/week), all 16 patients had very low serum Nagalase levels equivalent to those of healthy control values, indicating that these patients are tumor-free. No recurrence occurred for 7 years. PMID:18633461

  6. High Fc Density Particles Result in Binary Complement Activation but Tunable Macrophage Phagocytosis

    NASA Astrophysics Data System (ADS)

    Sulchek, Todd; Pacheco, Patricia; White, David

    2014-03-01

    Macrophage phagocytosis and complement system activation represent two key components of the immune system and both can be activated through the presentation of multiple Fc domains of IgG antibodies. We have created functionalized micro- and nanoparticles with various densities of Fc domains to understand the modulation of the immune system for eventual use as a novel immunomodulation platform. Phagocytosis assays were carried out by adding functionalized particles to macrophage cells and quantitatively determined using fluorescent microscopy and flow cytometry. Complement system activation by the functionalized particles in human serum was quantified with an enzyme immunoassay. Our phagocytosis assay revealed a strong dependence on particle size and Fc density. For small particles, as the Fc density increased, the number of particles phagocytosed also increased. Large particles were phagocytosed at significantly lower levels and showed no dependency on Fc density. Complement was successfully activated at levels comparable to positive controls for small particles at high Fc densities. However at low Fc densities, there is a significant decrease in complement activation. This result suggests a binary response for complement system activation with a threshold density for successful activation. Therefore, varying the Fc density on micro/nanoparticles resulted in a tunable response in macrophage phagocytosis while a more binary response for complement activation.

  7. Plexin-B2 negatively regulates macrophage motility, Rac, and Cdc42 activation.

    PubMed

    Roney, Kelly E; O'Connor, Brian P; Wen, Haitao; Holl, Eda K; Guthrie, Elizabeth H; Davis, Beckley K; Jones, Stephen W; Jha, Sushmita; Sharek, Lisa; Garcia-Mata, Rafael; Bear, James E; Ting, Jenny P-Y

    2011-01-01

    Plexins are cell surface receptors widely studied in the nervous system, where they mediate migration and morphogenesis though the Rho family of small GTPases. More recently, plexins have been implicated in immune processes including cell-cell interaction, immune activation, migration, and cytokine production. Plexin-B2 facilitates ligand induced cell guidance and migration in the nervous system, and induces cytoskeletal changes in overexpression assays through RhoGTPase. The function of Plexin-B2 in the immune system is unknown. This report shows that Plexin-B2 is highly expressed on cells of the innate immune system in the mouse, including macrophages, conventional dendritic cells, and plasmacytoid dendritic cells. However, Plexin-B2 does not appear to regulate the production of proinflammatory cytokines, phagocytosis of a variety of targets, or directional migration towards chemoattractants or extracellular matrix in mouse macrophages. Instead, Plxnb2(-/-) macrophages have greater cellular motility than wild type in the unstimulated state that is accompanied by more active, GTP-bound Rac and Cdc42. Additionally, Plxnb2(-/-) macrophages demonstrate faster in vitro wound closure activity. Studies have shown that a closely related family member, Plexin-B1, binds to active Rac and sequesters it from downstream signaling. The interaction of Plexin-B2 with Rac has only been previously confirmed in yeast and bacterial overexpression assays. The data presented here show that Plexin-B2 functions in mouse macrophages as a negative regulator of the GTPases Rac and Cdc42 and as a negative regulator of basal cell motility and wound healing. PMID:21966369

  8. Immunomodulation of RAW 264.7 murine macrophage functions and antioxidant activities of 11 plant extracts.

    PubMed

    Ghonime, Mohammed; Emara, Mohamed; Shawky, Riham; Soliman, Hesham; El-Domany, Ramadan; Abdelaziz, Ahmed

    2015-01-01

    A group of 11 medicinal plants, including Lavandula pubescens, Trigonella foenugricium, Salsola schweinforthi, Calligonum comosum, Silene succulenta, Silene villosa, Bogonvillea glabra, Cakile maritime, Gomphrene celesoids, Mirabilis jalaba, and Silene nocturna growing in Egypt, were extracted and examined for their immunomodulatory and antioxidant activities. RAW 264.7 cells were recruited to investigate the immunomodulatory effect through multiple parameters analysis. First, the proliferation index of macrophages cells was evaluated revealing that Trigonella foenugricium, Silene succulenta and Silene villosa have a significant cytotoxic effect on RAW cells. Interestingly, we observed enhancement of macrophages phagocytic function of by all extracts except Cakile maritime, Gomphrena celosioides and Silene nocturna. Afterwards, macrophages were challenged by incubation with LPS and the effect of various extracts on inflammatory responses was investigated; the generation of NO from activated macrophage was substantially suppressed by 7 extracts namely, Trigonella foenugricium, Calligonum comosum, Silene succulenta, Bougainvillea glabra, Mirabilis jalaba, Gomphrena celosioides and Silene nocturna. TNF-α was decreased by percentage range from 3.8 to 85.8% and Trigonella foenugricium extract showed the highest inhibition of TNF-α release. All extracts except Trigonella foenugricium, Salsola schweinforthi, Silene succulenta and Mirabilis jalaba significantly inhibited COX-2 production from stimulated macrophage. Moreover, evaluating the potential antioxidant activity of these extracts showed that Trigonella foenugricium, Salsola schweinforthi, Calligonum comosum, Bogonvillea glabra and Mirabilis jalaba exhibited some antioxidant activities. Taken together, our results suggest that some of these extracts may have a considerable antinflammatory and antioxidant effects and may be a potential therapeutic choice in the treatment of inflammatory diseases. PMID:25564700

  9. Administration of DHA Reduces Endoplasmic Reticulum Stress-Associated Inflammation and Alters Microglial or Macrophage Activation in Traumatic Brain Injury.

    PubMed

    Harvey, Lloyd D; Yin, Yan; Attarwala, Insiya Y; Begum, Gulnaz; Deng, Julia; Yan, Hong Q; Dixon, C Edward; Sun, Dandan

    2015-01-01

    We investigated the effects of the administration of docosahexaenoic acid (DHA) post-traumatic brain injury (TBI) on reducing neuroinflammation. TBI was induced by cortical contusion injury in Sprague Dawley rats. Either DHA (16 mg/kg in dimethyl sulfoxide) or vehicle dimethyl sulfoxide (1 ml/kg) was administered intraperitonially at 5 min after TBI, followed by a daily dose for 3 to 21 days. TBI triggered activation of microglia or macrophages, detected by an increase of Iba1 positively stained microglia or macrophages in peri-lesion cortical tissues at 3, 7, and 21 days post-TBI. The inflammatory response was further characterized by expression of the proinflammatory marker CD16/32 and the anti-inflammatory marker CD206 in Iba1(+) microglia or macrophages. DHA-treated brains showed significantly fewer CD16/32(+) microglia or macrophages, but an increased CD206(+) phagocytic microglial or macrophage population. Additionally, DHA treatment revealed a shift in microglial or macrophage morphology from the activated, amoeboid-like state into the more permissive, surveillant state. Furthermore, activated Iba1(+) microglial or macrophages were associated with neurons expressing the endoplasmic reticulum (ER) stress marker CHOP at 3 days post-TBI, and the administration of DHA post-TBI concurrently reduced ER stress and the associated activation of Iba1(+) microglial or macrophages. There was a decrease in nuclear translocation of activated nuclear factor kappa-light-chain-enhancer of activated B cells protein at 3 days in DHA-treated tissue and reduced neuronal degeneration in DHA-treated brains at 3, 7, and 21 days after TBI. In summary, our study demonstrated that TBI mediated inflammatory responses are associated with increased neuronal ER stress and subsequent activation of microglia or macrophages. DHA administration reduced neuronal ER stress and subsequent association with microglial or macrophage polarization after TBI, demonstrating its therapeutic

  10. Administration of DHA Reduces Endoplasmic Reticulum Stress-Associated Inflammation and Alters Microglial or Macrophage Activation in Traumatic Brain Injury

    PubMed Central

    Harvey, Lloyd D.; Yin, Yan; Attarwala, Insiya Y.; Begum, Gulnaz; Deng, Julia; Yan, Hong Q.; Dixon, C. Edward

    2015-01-01

    We investigated the effects of the administration of docosahexaenoic acid (DHA) post-traumatic brain injury (TBI) on reducing neuroinflammation. TBI was induced by cortical contusion injury in Sprague Dawley rats. Either DHA (16 mg/kg in dimethyl sulfoxide) or vehicle dimethyl sulfoxide (1 ml/kg) was administered intraperitonially at 5 min after TBI, followed by a daily dose for 3 to 21 days. TBI triggered activation of microglia or macrophages, detected by an increase of Iba1 positively stained microglia or macrophages in peri-lesion cortical tissues at 3, 7, and 21 days post-TBI. The inflammatory response was further characterized by expression of the proinflammatory marker CD16/32 and the anti-inflammatory marker CD206 in Iba1+ microglia or macrophages. DHA-treated brains showed significantly fewer CD16/32+ microglia or macrophages, but an increased CD206+ phagocytic microglial or macrophage population. Additionally, DHA treatment revealed a shift in microglial or macrophage morphology from the activated, amoeboid-like state into the more permissive, surveillant state. Furthermore, activated Iba1+ microglial or macrophages were associated with neurons expressing the endoplasmic reticulum (ER) stress marker CHOP at 3 days post-TBI, and the administration of DHA post-TBI concurrently reduced ER stress and the associated activation of Iba1+ microglial or macrophages. There was a decrease in nuclear translocation of activated nuclear factor kappa-light-chain-enhancer of activated B cells protein at 3 days in DHA-treated tissue and reduced neuronal degeneration in DHA-treated brains at 3, 7, and 21 days after TBI. In summary, our study demonstrated that TBI mediated inflammatory responses are associated with increased neuronal ER stress and subsequent activation of microglia or macrophages. DHA administration reduced neuronal ER stress and subsequent association with microglial or macrophage polarization after TBI, demonstrating its therapeutic potential to

  11. Macrophage-like tumor cells as tools to study chemoattractive activity.

    PubMed

    Terheggen, P; Van Loveren, H; Den Otter, W

    1985-12-01

    Macrophage-like tumor cells can be obtained in large quantities as rather homogeneous populations, making these cells useful for chemotaxis assays. Therefore, macrophage-like cells J774A, WEHI-3, P388D1, IC-21, and NCTC 1469, all of murine origin, and U937 of human origin, were tested for chemotactic activity to a number of chemoattractive agents, such as casein, an N-formyl tetrapeptide (N-formyl-L-norleucyl-L-leucyl-L-phenylalanyl-L-tyrosine), and culture supernatants of murine SL2 lymphoma cells. J774A and WEHI-3 macrophage-like cells of murine (BALB/c) origin expressed the strongest chemotactic activity to casein and N-formyl tetrapeptide, respectively. The results show that: very standardized chemotaxis assays can be performed using these cell lines; these assays require appropriate cell line-stimulus combinations; there are substantial differences among cell lines as to sensitivity to various chemoattractive substances; macrophage cell lines and functional mutants may be helpful for the study of receptors for chemotaxins and the study of transducer signals for chemotaxis. PMID:3864910

  12. Quercetin-3-O-glucuronide induces ABCA1 expression by LXRα activation in murine macrophages

    SciTech Connect

    Ohara, Kazuaki; Wakabayashi, Hideyuki; Taniguchi, Yoshimasa; Shindo, Kazutoshi; Yajima, Hiroaki; Yoshida, Aruto

    2013-11-29

    Highlights: •The major circulating quercetin metabolite (Q3GA) activated LXRα. •Q3GA induced ABCA1 via LXRα activation in macrophages. •Nelumbo nucifera leaf extracts contained quercetin glycosides. •N. nucifera leaf extract feeding elevated HDLC in mice. -- Abstract: Reverse cholesterol transport (RCT) removes excess cholesterol from macrophages to prevent atherosclerosis. ATP-binding cassette, subfamily A, member 1 (ABCA1) is a crucial cholesterol transporter involved in RCT to produce high density lipoprotein-cholesterol (HDLC), and is transcriptionally regulated by liver X receptor alpha (LXRα), a nuclear receptor. Quercetin is a widely distributed flavonoid in edible plants which prevented atherosclerosis in an animal model. We found that quercetin-3-O-glucuronide (Q3GA), a major quercetin metabolite after absorption from the digestive tract, enhanced ABCA1 expression, in vitro, via LXRα in macrophages. In addition, leaf extracts of a traditional Asian edible plant, Nelumbo nucifera (NNE), which contained abundant amounts of quercetin glycosides, significantly elevated plasma HDLC in mice. We are the first to present experimental evidence that Q3GA induced ABCA1 in macrophages, and to provide an alternative explanation to previous studies on arteriosclerosis prevention by quercetin.

  13. 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

  14. Kv1.3 potassium channel mediates macrophage migration in atherosclerosis by regulating ERK activity.

    PubMed

    Kan, Xiao-Hong; Gao, Hai-Qing; Ma, Zhi-Yong; Liu, Lin; Ling, Ming-Ying; Wang, Yuan-Yuan

    2016-02-01

    Ion channels expressed in macrophages have been tightly related to atherosclerosis by coupling cellular function. How the voltage-gated potassium channels (Kv) affect macrophage migration remain unknown. The aim of our study is to investigate whether Kv1.3-ERK signaling pathway plays an important role in the process. We explored the expression of Kv1.3 in coronary atherosclerotic heart disease and found Kv1.3 channel was increased in acute coronary syndrome patients. Treatment of RAW264.7 cells with Kv1.3 small interfering RNA, suppressed cell migration. The expression of phosphorylated ERK1/2 also decreased after knockdown of Kv1.3. On the other hand, overexpression of Kv1.3 channel promoted cell migration and ERK1/2 phosphorylation. U-0126, the mitogen-activated protein kinase inhibitors, could reverse macrophage migration induced by Kv1.3 channel overexpression. Downregulation of Kv1.3 channel by siRNA could not further inhibit cell migration when cells were treated with U-0126. It means that ERK is downstream signal of Kv1.3 channel. We concluded that Kv1.3 may stimulate macrophage migration through the activation of ERK. PMID:26748289

  15. 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

  16. Activation of macrophages stimulated by the bengkoang fiber extract through toll-like receptor 4.

    PubMed

    Kumalasari, Ika Dyah; Nishi, Kosuke; Putra, Agus Budiawan Naro; Sugahara, Takuya

    2014-07-25

    Bengkoang (Pachyrhizus erosus (L.) Urban) is an edible root tuber containing fairly large amounts of carbohydrates and crude fibers. Our previous studies showed that the bengkoang fiber extract (BFE) stimulates activation of macrophages, leading to induction of phagocytotic activity and cytokine production. In the present study we investigated the mechanism underlying activation of murine macrophages by BFE. BFE increased production of TNF-α, IL-6, and nitric oxide by J774.1 cells. In addition BFE also facilitated the gene expression levels of inducible nitric oxide synthase. We examined the effect of a TLR4 inhibitor on cytokine production to investigate the membrane receptor of macrophage activation by BFE. Treatment of J774.1 cells with the TLR4 inhibitor significantly inhibited production of IL-6 and TNF-α, suggesting that TLR4 is the target membrane receptor for BFE. The main signal molecules located downstream of TLR4 such as JNK, p38, ERK, and NF-κB were activated by BFE treatment. The immunostimulatory effect of BFE was cancelled by the pectinase treatment, suggesting that the active ingredient in BFE is pectin-like molecules. Overall results suggested that BFE activates J774.1 cells via the MAPK and NF-κB signaling pathways. PMID:24770453

  17. Alveolar Macrophage Recruitment and Activation by Chronic Second Hand Smoke Exposure in Mice

    PubMed Central

    Ellwanger, Almut; Solon, Margaret; Cambier, Christopher J.; Pinkerton, Kent E.; Koth, Laura L.

    2010-01-01

    Background Approximately 15% of cases of COPD occur in non-smokers. Among the potential risk factors for COPD in non-smokers is second hand smoke (SHS) exposure. However, the Surgeon General reported in 2006 that the evidence linking second hand smoke and COPD is insufficient to infer a causal relationship, largely because current evidence does not establish a biological link. Objectives The goal of this study was to determine whether SHS exposure can induce alveolar macrophage recruitment and expression of activation markers that we have previously demonstrated in human smokers and in mouse models of emphysema. To achieve these goals, we studied mice exposed to an ambient mixture of predominantly [89%] sidestream smoke at increasing doses over 3 months. Results We found that second hand smoke exposure induced a dose-dependent increase in alveolar macrophage recruitment (mean ± sd; 224,511 ± 52,330 vs 166,152 ± 47,989 macrophages/ml of bronchoalveolar lavage in smoke-exposed vs air-exposed controls at 3 months, p=0.003). We also found increased expression of several markers of alveolar macrophage activation (PLA2g7, dkfzp434l142, Trem-2, and pirin, all p<0.01 at 3 months) and increased lavage levels of two inflammatory mediators associated with COPD (CCL2 [MCP-1], 58 ± 12 vs. 43 ± 22 pg/ml, p=0.03; and TNFα, 138 ± 43 vs 88 ± 78 pg/ml, p=0.04 at 3 months). Conclusions These findings indicate that second smoke exposure can cause macrophage recruitment and activation, providing a biological link between second hand smoke exposure and the development of inflammatory processes linked to COPD. PMID:19378221

  18. Progesterone-induced activation of membrane-bound progesterone receptors in murine macrophage cells.

    PubMed

    Lu, Jing; Reese, Joshua; Zhou, Ying; Hirsch, Emmet

    2015-02-01

    Parturition is an inflammatory process mediated to a significant extent by macrophages. Progesterone (P4) maintains uterine quiescence in pregnancy, and a proposed functional withdrawal of P4 classically regulated by nuclear progesterone receptors (nPRs) leads to labor. P4 can affect the functions of macrophages despite the reported lack of expression of nPRs in these immune cells. Therefore, in this study we investigated the effects of the activation of the putative membrane-associated PR on the function of macrophages (a key cell for parturition) and discuss the implications of these findings for pregnancy and parturition. In murine macrophage cells (RAW 264.7), activation of mPRs by P4 modified to be active only extracellularly by conjugation to BSA (P4BSA, 1.0×10(-7) mol/l) caused a pro-inflammatory shift in the mRNA expression profile, with significant upregulation of the expression of cyclooxygenase 2 (COX2 (Ptgs2)), Il1B, and Tnf and downregulation of membrane progesterone receptor alpha (Paqr7) and oxytocin receptor (Oxtr). Pretreatment with PD98059, a MEK1/2 inhibitor, significantly reduced P4BSA-induced expression of mRNA of Il1B, Tnf, and Ptgs2. Inhibition of protein kinase A (PKA) by H89 blocked P4BSA-induced expression of Il1B and Tnf mRNA. P4BSA induced rapid phosphorylation of MEK1/2 and CREB (a downstream target of PKA). This phosphorylation was inhibited by pretreatment with PD98059 and H89, respectively, revealing that MEK1/2 and PKA are two of the components involved in mPR signaling. Taken together, these results indicate that changes in membrane progesterone receptor alpha expression and signaling in macrophages are associated with the inflammatory responses; and that these changes might contribute to the functional withdrawal of P4 related to labor. PMID:25472814

  19. Nf1+/- monocytes/macrophages induce neointima formation via CCR2 activation.

    PubMed

    Bessler, Waylan K; Kim, Grace; Hudson, Farlyn Z; Mund, Julie A; Mali, Raghuveer; Menon, Keshav; Kapur, Reuben; Clapp, D Wade; Ingram, David A; Stansfield, Brian K

    2016-03-15

    Persons with neurofibromatosis type 1 (NF1) have a predisposition for premature and severe arterial stenosis. Mutations in the NF1 gene result in decreased expression of neurofibromin, a negative regulator of p21(Ras), and increases Ras signaling. Heterozygous Nf1 (Nf1(+/-)) mice develop a marked arterial stenosis characterized by proliferating smooth muscle cells (SMCs) and a predominance of infiltrating macrophages, which closely resembles arterial lesions from NF1 patients. Interestingly, lineage-restricted inactivation of a single Nf1 allele in monocytes/macrophages is sufficient to recapitulate the phenotype observed in Nf1(+/-) mice and to mobilize proinflammatory CCR2+ monocytes into the peripheral blood. Therefore, we hypothesized that CCR2 receptor activation by its primary ligand monocyte chemotactic protein-1 (MCP-1) is critical for monocyte infiltration into the arterial wall and neointima formation in Nf1(+/-) mice. MCP-1 induces a dose-responsive increase in Nf1(+/-) macrophage migration and proliferation that corresponds with activation of multiple Ras kinases. In addition, Nf1(+/-) SMCs, which express CCR2, demonstrate an enhanced proliferative response to MCP-1 when compared with WT SMCs. To interrogate the role of CCR2 activation on Nf1(+/-) neointima formation, we induced neointima formation by carotid artery ligation in Nf1(+/-) and WT mice with genetic deletion of either MCP1 or CCR2. Loss of MCP-1 or CCR2 expression effectively inhibited Nf1(+/-) neointima formation and reduced macrophage content in the arterial wall. Finally, administration of a CCR2 antagonist significantly reduced Nf1(+/-) neointima formation. These studies identify MCP-1 as a potent chemokine for Nf1(+/-) monocytes/macrophages and CCR2 as a viable therapeutic target for NF1 arterial stenosis. PMID:26740548

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

    PubMed

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

    2002-05-01

    Alpha-N-acetyl galactosaminidase (alpha-NaGalase) has been reported to accumulate in serum of cancer patients and be responsible for deglycosylation of Gc protein, which is a precursor of GcMAF-mediated macrophage activation cascade, finally leading to immunosuppression in advanced cancer patients. We studied the biochemical characterization of alpha-NaGalase from several human tumor cell lines. We also examined its effect on the potency of GcMAF to activate mouse peritoneal macrophage to produce superoxide in GcMAF-mediated macrophage activation cascade. The specific activity of alpha-NaGalases from human colon tumor cell line HCT116, human hepatoma cell line HepG2, and normal human liver cells (Chang liver cell line) were evaluated using two types of substrates; GalNAc-alpha-PNP (exo-type substrate) and Gal-beta-GalNAc-alpha-PNP (endo-type substrate). Tumor-derived alpha-NaGalase having higher activity than normal alpha-NaGalase, had higher substrate specificity to the exo-type substrate than to the endo-type substrate, and still maintained its activity at pH 7. GcMAF enhance superoxide production in mouse macrophage, and pre-treatment of GcMAF with tumor cell lysate reduce the activity. We conclude that tumor-derived alpha-NaGalase is different in biochemical characterization compared to normal alpha-NaGalase from normal Chang liver cells. In addition, tumor cell-derived alpha-NaGalase decreases the potency of GcMAF on macrophage activation. PMID:12062184

  1. 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. PMID:26378074

  2. Superinduction of interleukin 8 mRNA in activated monocyte derived macrophages from rheumatoid arthritis patients

    PubMed Central

    Rodenburg, R.; van den Hoogen, F. H J; Barrera, P.; van Venrooij, W. J; van de Putte, L. B A

    1999-01-01

    OBJECTIVE—Synovial inflammation in patients with rheumatoid arthritis (RA) is characterised by the presence of large numbers of highly activated monocytes and macrophages. The importance of these cells in the aethiopathogenesis and prognosis of RA is increasingly recognised. The object of this report is to determine whether monocytes and monocyte derived macrophages of RA patients produce increased cytokine mRNA levels.
METHODS—Monocyte derived macrophages from RA patients and healthy controls were cultured either in the absence or presence of lipopolysaccharide. The expression levels of the mRNAs encoding GAPDH, interleukin 1β (IL1β), IL8, and α2 macroglobulin in these cells were analysed by reverse transcriptase-polymerase chain reaction (RT-PCR).
RESULTS—Activated monocyte derived macrophages from RA patients produce significantly higher IL8 mRNA levels than activated macrophages from healthy controls. By contrast, resting RA and control macrophages produce similar levels of IL8 mRNA. Culturing of activated macrophages in the presence of RA or control sera has no effect on the expression levels of IL8 mRNA. No significant differences between RA and control macrophages were observed in the expression levels of IL1β and α2 macroglobulin mRNAs.
CONCLUSION—These data indicate that the increased IL8 mRNA production capacity of RA macrophages upon activation is an intrinsic property of these cells, and is not attributable to factors present in the circulation. Based on these observations, it is postulated that this innate hyper-responsiveness of RA macrophages contributes to the high IL8 levels present in the synovial fluid of rheumatoid joints, and is implicated in the chemotactic gradient leading to the homing of leucocytes to the joints.

 PMID:10491366

  3. Pathways Involved in the Synergistic Activation of Macrophages by Lipoteichoic Acid and Hemoglobin

    PubMed Central

    Cox, Kathleen H.; Cox, Michelle E.; Woo-Rasberry, Virginia; Hasty, David L.

    2012-01-01

    Lipoteichoic acid (LTA) is a Gram-positive cell surface molecule that is found in both a cell-bound form and cell-free form in the host during an infection. Hemoglobin (Hb) can synergize with LTA, a TLR2 ligand, to potently activate macrophage innate immune responses in a TLR2- and TLR4-dependent way. At low levels of LTA, the presence of Hb can result in a 200-fold increase in the secretion of IL-6 following macrophage activation. Six hours after activation, the macrophage genes that are most highly up-regulated by LTA plus Hb activation compared to LTA alone are cytokines, chemokines, receptors and interferon-regulated genes. Several of these genes exhibit a unique TLR4-dependent increase in mRNA levels that continued to rise more than eight hours after stimulation. This prolonged increase in mRNA levels could be the result of an extended period of NF-κB nuclear localization and the concurrent absence of the NF-κB inhibitor, IκBα, after stimulation with LTA plus Hb. Dynasore inhibition experiments indicate that an endocytosis-dependent pathway is required for the TLR4-dependent up-regulation of IL-6 secretion following activation with LTA plus Hb. In addition, interferon-β mRNA is present after activation with LTA plus Hb, suggesting that the TRIF/TRAM-dependent pathway may be involved. Hb alone can elicit the TLR4-dependent secretion of TNF-α from macrophages, so it may be the TLR4 ligand. Hb also led to secretion of high mobility group box 1 protein (HMGB1), which synergized with LTA to increase secretion of IL-6. The activation of both the TLR2 and TLR4 pathways by LTA plus Hb leads to an enhanced innate immune response. PMID:23071790

  4. HIF-1α-PDK1 axis-induced active glycolysis plays an essential role in macrophage migratory capacity

    PubMed Central

    Semba, Hiroaki; Takeda, Norihiko; Isagawa, Takayuki; Sugiura, Yuki; Honda, Kurara; Wake, Masaki; Miyazawa, Hidenobu; Yamaguchi, Yoshifumi; Miura, Masayuki; Jenkins, Dana M. R.; Choi, Hyunsung; Kim, Jung-whan; Asagiri, Masataka; Cowburn, Andrew S.; Abe, Hajime; Soma, Katsura; Koyama, Katsuhiro; Katoh, Manami; Sayama, Keimon; Goda, Nobuhito; Johnson, Randall S.; Manabe, Ichiro; Nagai, Ryozo; Komuro, Issei

    2016-01-01

    In severely hypoxic condition, HIF-1α-mediated induction of Pdk1 was found to regulate glucose oxidation by preventing the entry of pyruvate into the tricarboxylic cycle. Monocyte-derived macrophages, however, encounter a gradual decrease in oxygen availability during its migration process in inflammatory areas. Here we show that HIF-1α-PDK1-mediated metabolic changes occur in mild hypoxia, where mitochondrial cytochrome c oxidase activity is unimpaired, suggesting a mode of glycolytic reprogramming. In primary macrophages, PKM2, a glycolytic enzyme responsible for glycolytic ATP synthesis localizes in filopodia and lammelipodia, where ATP is rapidly consumed during actin remodelling processes. Remarkably, inhibition of glycolytic reprogramming with dichloroacetate significantly impairs macrophage migration in vitro and in vivo. Furthermore, inhibition of the macrophage HIF-1α-PDK1 axis suppresses systemic inflammation, suggesting a potential therapeutic approach for regulating inflammatory processes. Our findings thus demonstrate that adaptive responses in glucose metabolism contribute to macrophage migratory activity. PMID:27189088

  5. HIF-1α-PDK1 axis-induced active glycolysis plays an essential role in macrophage migratory capacity.

    PubMed

    Semba, Hiroaki; Takeda, Norihiko; Isagawa, Takayuki; Sugiura, Yuki; Honda, Kurara; Wake, Masaki; Miyazawa, Hidenobu; Yamaguchi, Yoshifumi; Miura, Masayuki; Jenkins, Dana M R; Choi, Hyunsung; Kim, Jung-Whan; Asagiri, Masataka; Cowburn, Andrew S; Abe, Hajime; Soma, Katsura; Koyama, Katsuhiro; Katoh, Manami; Sayama, Keimon; Goda, Nobuhito; Johnson, Randall S; Manabe, Ichiro; Nagai, Ryozo; Komuro, Issei

    2016-01-01

    In severely hypoxic condition, HIF-1α-mediated induction of Pdk1 was found to regulate glucose oxidation by preventing the entry of pyruvate into the tricarboxylic cycle. Monocyte-derived macrophages, however, encounter a gradual decrease in oxygen availability during its migration process in inflammatory areas. Here we show that HIF-1α-PDK1-mediated metabolic changes occur in mild hypoxia, where mitochondrial cytochrome c oxidase activity is unimpaired, suggesting a mode of glycolytic reprogramming. In primary macrophages, PKM2, a glycolytic enzyme responsible for glycolytic ATP synthesis localizes in filopodia and lammelipodia, where ATP is rapidly consumed during actin remodelling processes. Remarkably, inhibition of glycolytic reprogramming with dichloroacetate significantly impairs macrophage migration in vitro and in vivo. Furthermore, inhibition of the macrophage HIF-1α-PDK1 axis suppresses systemic inflammation, suggesting a potential therapeutic approach for regulating inflammatory processes. Our findings thus demonstrate that adaptive responses in glucose metabolism contribute to macrophage migratory activity. PMID:27189088

  6. Dectin-1–Dependent LC3 Recruitment to Phagosomes Enhances Fungicidal Activity in Macrophages

    PubMed Central

    Tam, Jenny M.; Mansour, Michael K.; Khan, Nida S.; Seward, Michael; Puranam, Sravanthi; Tanne, Antoine; Sokolovska, Anna; Becker, Christine E.; Acharya, Mridu; Baird, Michelle A.; Choi, Augustine M. K.; Davidson, Michael W.; Segal, Brahm H.; Lacy-Hulbert, Adam; Stuart, Lynda M.; Xavier, Ramnik J.; Vyas, Jatin M.

    2014-01-01

    Autophagy has been postulated to play role in mammalian host defense against fungal pathogens, although the molecular details remain unclear. Here, we show that primary macrophages deficient in the autophagic factor LC3 demonstrate diminished fungicidal activity but increased cytokine production in response to Candida albicans stimulation. LC3 recruitment to fungal phagosomes requires activation of the fungal pattern receptor dectin-1. LC3 recruitment to the phagosome also requires Syk signaling but is independent of all activity by Toll-like receptors and does not require the presence of the adaptor protein Card9. We further demonstrate that reactive oxygen species generation by NADPH oxidase is required for LC3 recruitment to the fungal phagosome. These observations directly link LC3 to the inflammatory pathway against C. albicans in macrophages. PMID:24842831

  7. Dectin-1-dependent LC3 recruitment to phagosomes enhances fungicidal activity in macrophages.

    PubMed

    Tam, Jenny M; Mansour, Michael K; Khan, Nida S; Seward, Michael; Puranam, Sravanthi; Tanne, Antoine; Sokolovska, Anna; Becker, Christine E; Acharya, Mridu; Baird, Michelle A; Choi, Augustine M K; Davidson, Michael W; Segal, Brahm H; Lacy-Hulbert, Adam; Stuart, Lynda M; Xavier, Ramnik J; Vyas, Jatin M

    2014-12-01

    Autophagy has been postulated to play role in mammalian host defense against fungal pathogens, although the molecular details remain unclear. Here, we show that primary macrophages deficient in the autophagic factor LC3 demonstrate diminished fungicidal activity but increased cytokine production in response to Candida albicans stimulation. LC3 recruitment to fungal phagosomes requires activation of the fungal pattern receptor dectin-1. LC3 recruitment to the phagosome also requires Syk signaling but is independent of all activity by Toll-like receptors and does not require the presence of the adaptor protein Card9. We further demonstrate that reactive oxygen species generation by NADPH oxidase is required for LC3 recruitment to the fungal phagosome. These observations directly link LC3 to the inflammatory pathway against C. albicans in macrophages. PMID:24842831

  8. Neither classical nor alternative macrophage activation is required for Pneumocystis clearance during immune reconstitution inflammatory syndrome.

    PubMed

    Zhang, Zhuo-Qian; Wang, Jing; Hoy, Zachary; Keegan, Achsah; Bhagwat, Samir; Gigliotti, Francis; Wright, Terry W

    2015-12-01

    Pneumocystis is a respiratory fungal pathogen that causes pneumonia (Pneumocystis pneumonia [PcP]) in immunocompromised patients. Alveolar macrophages are critical effectors for CD4(+) T cell-dependent clearance of Pneumocystis, and previous studies found that alternative macrophage activation accelerates fungal clearance during PcP-related immune reconstitution inflammatory syndrome (IRIS). However, the requirement for either classically or alternatively activated macrophages for Pneumocystis clearance has not been determined. Therefore, RAG2(-/-) mice lacking either the interferon gamma (IFN-γ) receptor (IFN-γR) or interleukin 4 receptor alpha (IL-4Rα) were infected with Pneumocystis. These mice were then immune reconstituted with wild-type lymphocytes to preserve the normal T helper response while preventing downstream effects of Th1 or Th2 effector cytokines on macrophage polarization. As expected, RAG2(-/-) mice developed severe disease but effectively cleared Pneumocystis and resolved IRIS. Neither RAG/IFN-γR(-/-) nor RAG/IL-4Rα(-/-) mice displayed impaired Pneumocystis clearance. However, RAG/IFN-γR(-/-) mice developed a dysregulated immune response, with exacerbated IRIS and greater pulmonary function deficits than those in RAG2 and RAG/IL-4Rα(-/-) mice. RAG/IFN-γR(-/-) mice had elevated numbers of lung CD4(+) T cells, neutrophils, eosinophils, and NK cells but severely depressed numbers of lung CD8(+) T suppressor cells. Impaired lung CD8(+) T cell responses in RAG/IFN-γR(-/-) mice were associated with elevated lung IFN-γ levels, and neutralization of IFN-γ restored the CD8 response. These data demonstrate that restricting the ability of macrophages to polarize in response to Th1 or Th2 cytokines does not impair Pneumocystis clearance. However, a cell type-specific IFN-γ/IFN-γR-dependent mechanism regulates CD8(+) T suppressor cell recruitment, limits immunopathogenesis, preserves lung function, and enhances the resolution of PcP-related IRIS

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

    PubMed

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

    2008-11-01

    Methylglyoxal is a normal metabolite and has the potential to affect a wide variety of cellular processes. In particular, it can act selectively against malignant cells. The study described herein was to investigate whether methylglyoxal can enhance the non-specific immunity of the host against tumor cells. Methylglyoxal increased the number of macrophages in the peritoneal cavity of both normal and tumor-bearing mice. It also elevated the phagocytic capacity of macrophages in both these groups of animals. This activation of macrophages was brought about by increased production of Reactive Oxygen Intermediates (ROIs) and Reactive Nitrogen Intermediates (RNIs). The possible mechanism for the production of ROIs and RNIs can be attributed to stimulation of the respiratory burst enzyme NADPH oxidase and iNOS, respectively. IFN-gamma, which is a regulatory molecule of iNOS pathway also showed an elevated level by methylglyoxal. TNF-alpha, which is an important cytokine for oxygen independent killing by macrophage also increased by methylglyoxal in both tumor-bearing and non tumor-bearing animals. Methylglyoxal also played a role in the proliferation and cytotoxicity of splenic lymphocytes. In short, it can be concluded that methylglyoxal profoundly stimulates the immune system against tumor cells. PMID:18617020

  10. Assessment of phagocytic activity of cultured macrophages using fluorescence microscopy and flow cytometry.

    PubMed

    Sharma, Lokesh; Wu, Wenjun; Dholakiya, Sanjay L; Gorasiya, Samir; Wu, Jiao; Sitapara, Ravikumar; Patel, Vivek; Wang, Mao; Zur, Michelle; Reddy, Shloka; Siegelaub, Nathan; Bamba, Katrina; Barile, Frank A; Mantell, Lin L

    2014-01-01

    Phagocytosis is the process by which phagocytes, including macrophages, neutrophils and monocytes, engulf and kill invading pathogens, remove foreign particles, and clear cell debris. Phagocytes and their ability to phagocytose are an important part of the innate immune system and are critical for homeostasis of the host. Impairment in phagocytosis has been associated with numerous diseases and disorders. Different cytokines have been shown to affect the phagocytic process. Cytokines including TNFα, IL-1β, GM-CSF, and TGF-β1 were found to promote phagocytosis, whereas high mobility group box-1 (HMGB1) inhibited the phagocytic function of macrophages. Here, we describe two commonly used methods to assess the phagocytic function of cultured macrophages, which can easily be applied to other phagocytes. Each method is based on the extent of engulfment of FITC-labeled latex minibeads by macrophages under different conditions. Phagocytic activity can be assessed either by counting individual cells using a fluorescence microscope or measuring fluorescence intensity using a flow cytometer. PMID:24908301

  11. Mycobacterium indicus pranii and Mycobacterium bovis BCG lead to differential macrophage activation in Toll-like receptor-dependent manner.

    PubMed

    Kumar, Pawan; Tyagi, Rohit; Das, Gobardhan; Bhaskar, Sangeeta

    2014-10-01

    Mycobacterium indicus pranii (MIP) is an atypical mycobacterial species possessing strong immunomodulatory properties. It is a potent vaccine candidate against tuberculosis, promotes Th1 immune response and protects mice from tumours. In previous studies, we demonstrated higher protective efficacy of MIP against experimental tuberculosis as compared with bacillus Calmette-Guérin (BCG). Since macrophages play an important role in the pathology of mycobacterial diseases and cancer, in the present study, we evaluated the MIP in live and killed form for macrophage activation potential, compared it with BCG and investigated the underlying mechanisms. High levels of tumour necrosis factor-α, interleukin-12p40 (IL-12p40), IL-6 and nitric oxide were produced by MIP-stimulated macrophages as compared with BCG-stimulated macrophages. Prominent up-regulation of co-stimulatory molecules CD40, CD80 and CD86 was also observed in response to MIP. Loss of response in MyD88-deficient macrophages showed that both MIP and BCG activate the macrophages in a MyD88-dependent manner. MyD88 signalling pathway culminates in nuclear factor-κB/activator protein-1 (NF-κB/AP-1) activation and higher activation of NF-κB/AP-1 was observed in response to MIP. With the help of pharmacological inhibitors and Toll-like receptor (TLR) -deficient macrophages, we observed the role of TLR2, TLR4 and intracellular TLRs in MIP-mediated macrophage activation. Stimulation of HEK293 cells expressing TLR2 in homodimeric or heterodimeric form showed that MIP has a distinctly higher level of TLR2 agonist activity compared with BCG. Further experiments suggested that TLR2 ligands are well exposed in MIP whereas they are obscured in BCG. Our findings establish the higher macrophage activation potential of MIP compared with BCG and delineate the underlying mechanism. PMID:24766519

  12. Molecular Mechanism of Macrophage Activation by Red Ginseng Acidic Polysaccharide from Korean Red Ginseng

    PubMed Central

    Byeon, Se Eun; Lee, Jaehwi; Kim, Ji Hye; Yang, Woo Seok; Kwak, Yi-Seong; Kim, Sun Young; Choung, Eui Su; Rhee, Man Hee; Cho, Jae Youl

    2012-01-01

    Red ginseng acidic polysaccharide (RGAP), isolated from Korean red ginseng, displays immunostimulatory and antitumor activities. Even though numerous studies have been reported, the mechanism as to how RGAP is able to stimulate the immune response is not clear. In this study, we aimed to explore the mechanism of molecular activation of RGAP in macrophages. RGAP treatment strongly induced NO production in RAW264.7 cells without altering morphological changes, although the activity was not strong compared to LPS-induced dendritic-like morphology in RAW264.7 cells. RGAP-induced NO production was accompanied with enhanced mRNA levels of iNOS and increases in nuclear transcription factors such as NF-κB, AP-1, STAT-1, ATF-2, and CREB. According to pharmacological evaluation with specific enzyme inhibitors, Western blot analysis of intracellular signaling proteins and inhibitory pattern using blocking antibodies, ERK, and JNK were found to be the most important signaling enzymes compared to LPS signaling cascade. Further, TLR2 seems to be a target surface receptor of RGAP. Lastly, macrophages isolated from RGS2 knockout mice or wortmannin exposure strongly upregulated RGAP-treated NO production. Therefore, our results suggest that RGAP can activate macrophage function through activation of transcription factors such as NF-κB and AP-1 and their upstream signaling enzymes such as ERK and JNK. PMID:22474399

  13. Krüppel like factor 4 promoter undergoes active demethylation during monocyte/macrophage differentiation.

    PubMed

    Karpurapu, Manjula; Ranjan, Ravi; Deng, Jing; Chung, Sangwoon; Lee, Yong Gyu; Xiao, Lei; Nirujogi, Teja Srinivas; Jacobson, Jeffrey R; Park, Gye Young; Christman, John W

    2014-01-01

    The role of different lineage specific transcription factors in directing hematopoietic cell fate towards myeloid lineage is well established but the status of epigenetic modifications has not been defined during this important developmental process. We used non proliferating, PU.1 inducible myeloid progenitor cells and differentiating bone marrow derived macrophages to study the PU.1 dependent KLF4 transcriptional regulation and its promoter demethylation during monocyte/macrophage differentiation. Expression of KLF4 was regulated by active demethylation of its promoter and PU.1 specifically bound to KLF4 promoter oligo harboring the PU.1 consensus sequence. Methylation specific quantitative PCR and Bisulfite sequencing indicated demethylation of CpG residues most proximal to the transcription start site of KLF4 promoter. Cloned KLF4 promoter in pGL3 Luciferase and CpG free pcpgf-bas vectors showed accentuated reporter activity when co-transfected with the PU.1 expression vector. In vitro methylation of both KLF4 promoter oligo and cloned KLF4 promoter vectors showed attenuated in vitro DNA binding activity and Luciferase/mouse Alkaline phosphotase reporter activity indicating the negative influence of KLF4 promoter methylation on PU.1 binding. The Cytosine deaminase, Activation Induced Cytidine Deaminase (AICDA) was found to be critical for KLF4 promoter demethylation. More importantly, knock down of AICDA resulted in blockade of KLF4 promoter demethylation, decreased F4/80 expression and other phenotypic characters of macrophage differentiation. Our data proves that AICDA mediated active demethylation of the KLF4 promoter is necessary for transcriptional regulation of KLF4 by PU.1 during monocyte/macrophage differentiation. PMID:24695324

  14. Stimulation of lymphocyte anti-melanoma activity by co-cultured macrophages activated by complex homeopathic medication

    PubMed Central

    2009-01-01

    Background Melanoma is the most aggressive form of skin cancer, and the most rapidly expanding cancer in terms of worldwide incidence. Chemotherapeutic approaches to treat melanoma have been uniformly disappointing. A Brazilian complex homeopathic medication (CHM), used as an immune modulator, has been recommended for patients with depressed immune systems. Previous studies in mice have demonstrated that the CHM activates macrophages, induces an increase in the number of leukocytes and improves the murine response against Sarcoma-180. Methods Here we studied the interaction of mouse lymph node lymphocytes, co-cultured in vitro with macrophages in the presence or absence of the CHM, with B16F10 melanoma cells. Results Lymphocytes co-cultured with macrophages in the presence of the CHM had greater anti-melanoma activity, reducing melanoma cell density and increasing the number of lysed tumor cells. There was also a higher proportion of activated (CD25+) lymphocytes with increased viability. Overall, lymphocytes activated by treatment destroyed growing cancer cells more effectively than control lymphocytes. Conclusion Co-culture of macrophages with lymphocytes in the presence of the CHM enhanced the anti-cancer performance of lymphocytes against a very aggressive lineage of melanoma cells. These results suggest that non-toxic therapies using CHMs are a promising alternative approach to the treatment of melanomas. In addition, they are attractive combination-therapy candidates, which may enhance the efficacy of conventional medicines by improving the immune response against tumor cells. PMID:19698142

  15. ELECTROSTATIC CHARGE ON NANO-PARTICLES ACTIVATES CNS MACROPHAGES (MICROGLIA).

    EPA Science Inventory

    Nanometer size particles carry free radical activity on their surface and can produce oxidative stress (OS)-mediated damage upon impact to target cells. The initiating event of phage cell activation (i.e., the oxidative burst) is unknown, although many proximal events have been i...

  16. Effects of Nanosized Lithium Carbonate Particles on the Functional Activity of Macrophages During Development of Hepatocarcinoma 29.

    PubMed

    Konenkov, V I; Borodin, Yu I; Makarova, O P; Bgatova, N P; Rachkovskaya, L N

    2015-08-01

    The functional activity of macrophages in response to injection of nanosized lithium carbonate particles after initiation of hepatocarcinoma 29 in male CBA mice was evaluated by the production of NO, arginase activity, and absorption of zymosan granules. In intact animals, NO production by peritoneal macrophages increased by 4 times and arginase activity 3.1 times in response to a single injection of nanosized particles into the hip muscle. The level of NO production by macrophages remained high after 4 and 5 injections, while arginase activity returned to normal. The level of phagocytic peritoneal macrophages increased by 1.4 times after 5 injections of the particles. The level of NO production by macrophages gradually increased in animals with hepatocarcinoma developing in the hip muscle: by 1.6 times on day 3, 3.2 times on day 7, and by 2.6 times on day 13 in comparison with the corresponding parameters in intact animals. The increase of NO production by peritoneal macrophages after tumor process initiation was not paralleled by changes in arginase activity and absorption of zymosan granules. The results indicated that injection of nanosized lithium carbonate particles after inoculation of hepatocarcinoma 29 cells in the right hip muscle tissue was inessential for the function of peritoneal macrophages by the studied parameters. PMID:26388569

  17. p58IPK suppresses NLRP3 inflammasome activation and IL-1β production via inhibition of PKR in macrophages

    PubMed Central

    Boriushkin, Evgenii; Wang, Joshua J.; Li, Junhua; Bhatta, Maulasri; Zhang, Sarah X.

    2016-01-01

    The NLRP3 inflammasome activation is a key signaling event for activation and secretion of pro-inflammatory cytokines such as IL-1β from macrophages. p58IPK is a molecular chaperone that regulates protein homeostasis through inhibiting eIF-2α kinases including double-stranded RNA–dependent protein kinase (PKR), which has been recently implicated in inflammasome activation. Herein we investigate the role of p58IPK in TLR4 signaling and inflammasome activation in macrophages. Primary bone marrow-derived macrophages (BMDM) was isolated from p58IPK knockout (KO) and wildtype (WT) mice and treated with lipopolysaccharide (LPS) and ATP to activate TLR4 signaling and stimulate inflammasome activation. Compared to WT macrophages, p58IPK deficient cells demonstrated significantly stronger activation of PKR, NF-κB, and JNK and higher expression of pro-inflammatory genes TNF-α and IL-1β. Coincidently, p58IPK deletion intensified NLRP3-inflammasome activation indicated by enhanced caspase 1 cleavage and increased IL-1β maturation and secretion. Pretreatment with specific PKR inhibitor or overexpression of p58IPK largely abolished the changes in inflammasome activation and IL-1β secretion in p58IPK null macrophages. Furthermore, immunoprecipitation assay confirmed the binding of p58IPK with PKR, but not other TLR4 downstream signaling molecules. Collectively, these results suggest a novel and crucial role of p58IPK in regulation of inflammasome activation and IL-1β secretion in macrophages. PMID:27113095

  18. Ionizing Radiation Induces Macrophage Foam Cell Formation and Aggregation Through JNK-Dependent Activation of CD36 Scavenger Receptors

    SciTech Connect

    Katayama, Ikuo; Hotokezaka, Yuka; Matsuyama, Toshifumi; Sumi, Tadateru; Nakamura, Takashi

    2008-03-01

    Purpose: Irradiated arteries of cancer patients can be associated with atherosclerosis-like lesions containing cholesterol-laden macrophages (foam cells). Endothelial cell damage by irradiation does not completely explain the foam cell formation. We investigated the possible underlying mechanisms for ionizing radiation (IR)-induced foam cell formation. Methods and Materials: Human peripheral blood monocytes were activated by macrophage colony-stimulating factor and then treated with varying doses of IR in vitro in the absence of endothelial cells. Scavenger receptor expression and foam cell formation of IR-treated macrophages were investigated in the presence or absence of oxidized low-density lipoprotein. We also assessed the importance of mitogen-activated protein kinase activity in the macrophage colony-stimulating factor-activated human monocytes (macrophages) for the foam cell formation. Results: We found that IR treatment of macrophage colony-stimulating factor-activated human peripheral blood monocytes resulted in the enhanced expression of CD36 scavenger receptors and that cholesterol accumulated in the irradiated macrophages with resultant foam cell formation in the presence of oxidized low-density lipoprotein. Furthermore, when cultured on collagen gels, human macrophages formed large foam cell aggregates in response to IR. Antibodies against CD36 inhibited the IR-induced foam cell formation and aggregation, indicating that the IR-induced foam cell formation and the subsequent aggregation are dependent on functional CD36. In addition, we found that IR of human macrophages resulted in c-Jun N-terminal kinase activation and that c-Jun N-terminal kinase inhibition suppressed IR-induced CD36 expression and the subsequent foam cell formation and aggregation. Conclusion: Taken together, these results suggest that IR-induced foam cell formation is mediated by c-Jun N-terminal kinase-dependent CD36 activation.

  19. ACROLEIN ACTIVATES MATRIX METALLOPROTEINASES BY INCREASING REACTIVE OXYGEN SPECIES IN MACROPHAGES

    PubMed Central

    O’Toole, Timothy E.; Zheng, Yu-Ting; Hellmann, Jason; Conklin, Daniel J.; Barski, Oleg; Bhatnagar, Aruni

    2009-01-01

    Acrolein is a ubiquitous component of environmental pollutants such as automobile exhaust, cigarette, wood, and coal smoke. It is also a natural constituent of several foods and is generated endogenously during inflammation or oxidation of unsaturated lipids. Because increased inflammation and episodic exposure to acrolein-rich pollutants such as traffic emissions or cigarette smoke have been linked to acute myocardial infarction, we examined the effects of acrolein on matrix metalloproteinases (MMPs), which destabilize atherosclerotic plaques. Our studies show that exposure to acrolein resulted in the secretion of MMP-9 from differentiated THP-1 macrophages. Acrolein-treatment of macrophages also led to an increase in reactive oxygen species (ROS), free intracellular calcium ([Ca2+]i), and xanthine oxidase (XO) activity. ROS production was prevented by allopurinol, but not by rotenone or apocynin and by buffering changes in [Ca2+]I with BAPTA-AM. The increase in MMP production was abolished by pre-treatment with the antioxidants Tiron and N-acetyl cysteine (NAC) or with the xanthine oxidase inhibitors allopurinol or oxypurinol. Finally, MMP activity was significantly stimulated in aortic sections from apoE-null mice containing advanced atherosclerotic lesions after exposure to acrolein ex vivo. These observations suggest that acrolein exposure results in MMP secretion from macrophages via a mechanism that involves an increase in [Ca2+]I, leading to xanthine oxidase activation and an increase in ROS production. ROS-dependent activation of MMPs by acrolein could destabilize atherosclerotic lesions during brief episodes of inflammation or pollutant exposure. PMID:19371603

  20. Acrolein activates matrix metalloproteinases by increasing reactive oxygen species in macrophages.

    PubMed

    O'Toole, Timothy E; Zheng, Yu-Ting; Hellmann, Jason; Conklin, Daniel J; Barski, Oleg; Bhatnagar, Aruni

    2009-04-15

    Acrolein is a ubiquitous component of environmental pollutants such as automobile exhaust, cigarette, wood, and coal smoke. It is also a natural constituent of several foods and is generated endogenously during inflammation or oxidation of unsaturated lipids. Because increased inflammation and episodic exposure to acrolein-rich pollutants such as traffic emissions or cigarette smoke have been linked to acute myocardial infarction, we examined the effects of acrolein on matrix metalloproteinases (MMPs), which destabilize atherosclerotic plaques. Our studies show that exposure to acrolein resulted in the secretion of MMP-9 from differentiated THP-1 macrophages. Acrolein-treatment of macrophages also led to an increase in reactive oxygen species (ROS), free intracellular calcium ([Ca2+](i)), and xanthine oxidase (XO) activity. ROS production was prevented by allopurinol, but not by rotenone or apocynin and by buffering changes in [Ca2+](I) with BAPTA-AM. The increase in MMP production was abolished by pre-treatment with the antioxidants Tiron and N-acetyl cysteine (NAC) or with the xanthine oxidase inhibitors allopurinol or oxypurinol. Finally, MMP activity was significantly stimulated in aortic sections from apoE-null mice containing advanced atherosclerotic lesions after exposure to acrolein ex vivo. These observations suggest that acrolein exposure results in MMP secretion from macrophages via a mechanism that involves an increase in [Ca2+](I), leading to xanthine oxidase activation and an increase in ROS production. ROS-dependent activation of MMPs by acrolein could destabilize atherosclerotic lesions during brief episodes of inflammation or pollutant exposure. PMID:19371603

  1. Expression and kinetics of induced procoagulant activity in bovine pulmonary alveolar macrophages.

    PubMed

    Car, B D; Slauson, D O; Suyemoto, M M; Doré, M; Neilsen, N R

    1991-01-01

    Leukocytes, especially macrophages, are important cellular mediators of fibrin deposition and removal at tissue sites of inflammation. Pulmonary fibrin deposition is a prominent feature of bovine acute lung injury; therefore, we studied the resting and stimulated procoagulant responses of bovine pulmonary alveolar macrophages (PAM) and peripheral blood neutrophils (PMN). Freshly isolated normal PAM and PMN expressed negligible procoagulant activity. PAM stimulated with endotoxin lipopolysaccharide (LPS), 4 beta-phorbol 12-myristate 13-acetate (PMA) and bovine recombinant interleukin-1 beta (rBIL-1 beta) exhibited protein synthesis- and dose-dependent enhancement of procoagulant activity in 8-h cultures. Bovine recombinant granulocyte macrophage-colony stimulating factor (rBGM-CSF) and recombinant human gamma-interferon (rHIFN-gamma) did not induce procoagulant activity. The kinetics of LPS- and PMA-enhanced PAM procoagulant activity differed: LPS-induced enhancement developed earlier and more rapidly than PMA-induced enhancement. Pasteurella haemolytica LPS was more potent than Escherichia coli LPS in enhancing PAM procoagulant activity, while dexamethasone decreased both baseline and LPS- or PMA-stimulated activity by approximately 50%. PAM procoagulant activity resulted from tissue factor expression. Bovine PMN produced negligible procoagulant activity when stimulated, and are thus unlikely to be major contributors to procoagulant activity in bovine lung. Activity inhibitory to bovine tissue factor was present in both calf and adult sera, and was partly dependent on the presence of factor X for activity. Rapid induction of bovine PAM procoagulant activity by inflammatory mediators, and subsequent resistance to degradation, may thus combine to promote an alveolar microenvironment permissive to fibrin deposition in bovine acute lung injury. PMID:1959504

  2. Immunosuppressive activity induced by nitric oxide in culture supernatant of activated rat alveolar macrophages.

    PubMed Central

    Kawabe, T; Isobe, K I; Hasegawa, Y; Nakashima, I; Shimokata, K

    1992-01-01

    Alveolar macrophages (AM) from normal rats had immunosuppressive activity to mitogen-induced proliferative responses of splenic lymphocytes. We studied the mechanism and the implication of the nitric oxide synthetase pathway in AM-mediated suppression of concanavalin A (Con A)-induced lymphocyte proliferation. The culture supernatant from AM cultures alone did not have immunosuppressive activity to Con A-induced proliferative responses of non-adherent spleen cells (n-ad SC), but the culture supernatant from co-culture of AM and autologous n-ad SC had this activity. Con A-pulsed AM also liberated the immunosuppressive factor. When AM and autologous n-ad SC were cultured separately under the condition that medium could freely communicate, the culture supernatant did not suppress the Con A-induced proliferative response of n-ad SC. This indicated that the immunosuppressive factor was liberated when AM was activated by cell-to-cell contact with n-ad SC. Further, we examined the immunosuppressive activity of the culture supernatant of co-culture of AM and autologous n-ad SC to Con A-induced responses of allogeneic n-ad SC and xenogeneic murine n-ad SC, and allogeneic mixed leucocyte reaction, and found that this culture supernatant could suppress all these proliferative responses. Nitrate (NO2-) synthesis was markedly augmented in the culture supernatants of Con A-pulsed AM and co-culture of AM and n-ad SC. NG-monomethyl-L-arginine (MMA), a specific competitive inhibitor of the nitric oxide synthetase pathway (NOSP), extinguished both NO2- synthesis by AM and AM-mediated immunosuppressive activity. These data suggest that NOSP was important in AM-mediated suppression of Con A-induced lymphocyte proliferation. PMID:1385798

  3. Avirulent strains of Toxoplasma gondii infect macrophages by active invasion from the phagosome.

    PubMed

    Zhao, Yanlin; Marple, Andrew H; Ferguson, David J P; Bzik, David J; Yap, George S

    2014-04-29

    Unlike most intracellular pathogens that gain access into host cells through endocytic pathways, Toxoplasma gondii initiates infection at the cell surface by active penetration through a moving junction and subsequent formation of a parasitophorous vacuole. Here, we describe a noncanonical pathway for T. gondii infection of macrophages, in which parasites are initially internalized through phagocytosis, and then actively invade from within a phagosomal compartment to form a parasitophorous vacuole. This phagosome to vacuole invasion (PTVI) pathway may represent an intermediary link between the endocytic and the penetrative routes for host cell entry by intracellular pathogens. The PTVI pathway is preferentially used by avirulent strains of T. gondii and confers an infectious advantage over virulent strains for macrophage tropism. PMID:24733931

  4. Avirulent strains of Toxoplasma gondii infect macrophages by active invasion from the phagosome

    PubMed Central

    Zhao, Yanlin; Marple, Andrew H.; Ferguson, David J. P.; Bzik, David J.; Yap, George S.

    2014-01-01

    Unlike most intracellular pathogens that gain access into host cells through endocytic pathways, Toxoplasma gondii initiates infection at the cell surface by active penetration through a moving junction and subsequent formation of a parasitophorous vacuole. Here, we describe a noncanonical pathway for T. gondii infection of macrophages, in which parasites are initially internalized through phagocytosis, and then actively invade from within a phagosomal compartment to form a parasitophorous vacuole. This phagosome to vacuole invasion (PTVI) pathway may represent an intermediary link between the endocytic and the penetrative routes for host cell entry by intracellular pathogens. The PTVI pathway is preferentially used by avirulent strains of T. gondii and confers an infectious advantage over virulent strains for macrophage tropism. PMID:24733931

  5. YC-1 potentiates cAMP-induced CREB activation and nitric oxide production in alveolar macrophages

    SciTech Connect

    Hwang, Tsong-Long; Tang, Ming-Chi; Kuo, Liang-Mou; Chang, Wen-De; Chung, Pei-Jen; Chang, Ya-Wen; Fang, Yao-Ching

    2012-04-15

    Alveolar macrophages play significant roles in the pathogenesis of several inflammatory lung diseases. Increases in exhaled nitric oxide (NO) are well documented to reflect disease severity in the airway. In this study, we investigated the effect of 3-(5′-hydroxymethyl-2′-furyl)-1-benzyl indazole (YC-1), a known activator of soluble guanylyl cyclase, on prostaglandin (PG)E{sub 1} (a stable PGE{sub 2} analogue) and forskolin (a adenylate cyclase activator) induced NO production and inducible NO synthase (iNOS) expression in rat alveolar macrophages (NR8383). YC-1 did not directly cause NO production or iNOS expression, but drastically potentiated PGE{sub 1}- or forskolin-induced NO production and iNOS expression in NR8383 alveolar macrophages. Combination treatment with YC-1 and PGE{sub 1} significantly increased phosphorylation of the cAMP response element-binding protein (CREB), but not nuclear factor (NF)-κB activation. The combined effect on NO production, iNOS expression, and CREB phosphorylation was reversed by a protein kinase (PK)A inhibitor (H89), suggesting that the potentiating functions were mediated through a cAMP/PKA signaling pathway. Consistent with this, cAMP analogues, but not the cGMP analogue, caused NO release, iNOS expression, and CREB activation. YC-1 treatment induced an increase in PGE{sub 1}-induced cAMP formation, which occurred through the inhibition of cAMP-specific phosphodiesterase (PDE) activity. Furthermore, the combination of rolipram (an inhibitor of PDE4), but not milronone (an inhibitor of PDE3), and PGE{sub 1} also triggered NO production and iNOS expression. In summary, YC-1 potentiates PGE{sub 1}-induced NO production and iNOS expression in alveolar macrophages through inhibition of cAMP PDE activity and activation of the cAMP/PKA/CREB signaling pathway. Highlights: ► YC-1 potentiated PGE1-induced iNOS expression in alveolar macrophages. ► The combination of YC-1 and PGE1 increased CREB but not NFκB activation.

  6. LRH-1 mediates anti-inflammatory and antifungal phenotype of IL-13-activated macrophages through the PPARγ ligand synthesis

    PubMed Central

    Lefèvre, Lise; Authier, Hélène; Stein, Sokrates; Majorel, Clarisse; Couderc, Bettina; Dardenne, Christophe; Eddine, Mohamad Ala; Meunier, Etienne; Bernad, José; Valentin, Alexis; Pipy, Bernard; Schoonjans, Kristina; Coste, Agnès

    2015-01-01

    Liver receptor homologue-1 (LRH-1) is a nuclear receptor involved in the repression of inflammatory processes in the hepatointestinal tract. Here we report that LRH-1 is expressed in macrophages and induced by the Th2 cytokine IL-13 via a mechanism involving STAT6. We show that loss-of-function of LRH-1 in macrophages impedes IL-13-induced macrophage polarization due to impaired generation of 15-HETE PPARγ ligands. The incapacity to generate 15-HETE metabolites is at least partially caused by the compromised regulation of CYP1A1 and CYP1B1. Mice with LRH-1-deficient macrophages are, furthermore, highly susceptible to gastrointestinal and systemic Candida albicans infection. Altogether, these results identify LRH-1 as a critical component of the anti-inflammatory and fungicidal response of alternatively activated macrophages that acts upstream from the IL-13-induced 15-HETE/PPARγ axis. PMID:25873311

  7. Hypoxia in Leishmania major skin lesions impairs the NO-dependent leishmanicidal activity of macrophages.

    PubMed

    Mahnke, Alexander; Meier, Robert J; Schatz, Valentin; Hofmann, Julian; Castiglione, Kirstin; Schleicher, Ulrike; Wolfbeis, Otto S; Bogdan, Christian; Jantsch, Jonathan

    2014-09-01

    Cure of infections with Leishmania major is critically dependent on the ability of macrophages to induce the type 2 nitic oxide (NO) synthase (NOS2) that produces high levels of NO in the presence of ample oxygen. Therefore, we analyzed the oxygen levels found in leishmanial skin lesions and their effect on the NOS2-dependent leishmanicidal activity of macrophages (MΦ). When L. major skin lesions of self-healing C57BL/6 mice reached their maximum size, the infected tissue displayed low oxygen levels (pO2∼21 Torr). MΦ activated under these oxygen tensions failed to produce sufficient amounts of NO to clear L. major. Nos2-deficient and hypoxic wild-type macrophages displayed a similar phenotype. Killing was restored when MΦ were reoxygenated or exposed to a NO donor. The resolution of the lesion in C57BL/6 mice was paralleled by an increase of lesional pO2. When mice were kept under normobaric hypoxia, this caused a persistent suppression of the lesional pO2 and a concurrent increase of the parasite load. In Nos2-deficient mice, there was no effect of atmospheric hypoxia. Low oxygen levels found at leishmanial skin lesions impaired the NOS2-dependent leishmanicidal activity of MΦ. Hence, tissue oxygenation represents an underestimated local milieu factor that participates in the persistence of Leishmania. PMID:24583949

  8. Involvement of Toso in activation of monocytes, macrophages, and granulocytes.

    PubMed

    Lang, Karl S; Lang, Philipp A; Meryk, Andreas; Pandyra, Aleksandra A; Boucher, Louis-Martin; Pozdeev, Vitaly I; Tusche, Michael W; Göthert, Joachim R; Haight, Jillian; Wakeham, Andrew; You-Ten, Annick J; McIlwain, David R; Merches, Katja; Khairnar, Vishal; Recher, Mike; Nolan, Garry P; Hitoshi, Yasumichi; Funkner, Pauline; Navarini, Alexander A; Verschoor, Admar; Shaabani, Namir; Honke, Nadine; Penn, Linda Z; Ohashi, Pamela S; Häussinger, Dieter; Lee, Kyeong-Hee; Mak, Tak W

    2013-02-12

    Rapid activation of immune responses is necessary for antibacterial defense, but excessive immune activation can result in life-threatening septic shock. Understanding how these processes are balanced may provide novel therapeutic potential in treating inflammatory disease. Fc receptors are crucial for innate immune activation. However, the role of the putative Fc receptor for IgM, known as Toso/Faim3, has to this point been unclear. In this study, we generated Toso-deficient mice and used them to uncover a critical regulatory function of Toso in innate immune activation. Development of innate immune cells was intact in the absence of Toso, but Toso-deficient neutrophils exhibited more reactive oxygen species production and reduced phagocytosis of pathogens compared with controls. Cytokine production was also decreased in Toso(-/-) mice compared with WT animals, rendering them resistant to septic shock induced by lipopolysaccharide. However, Toso(-/-) mice also displayed limited cytokine production after infection with the bacterium Listeria monocytogenes that was correlated with elevated presence of Listeria throughout the body. Accordingly, Toso(-/-) mice succumbed to infections of L. monocytogenes, whereas WT mice successfully eliminated the infection. Taken together, our data reveal Toso to be a unique regulator of innate immune responses during bacterial infection and septic shock. PMID:23359703

  9. Involvement of Toso in activation of monocytes, macrophages, and granulocytes

    PubMed Central

    Lang, Karl S.; Lang, Philipp A.; Meryk, Andreas; Pandyra, Aleksandra A.; Boucher, Louis-Martin; Pozdeev, Vitaly I.; Tusche, Michael W.; Göthert, Joachim R.; Haight, Jillian; Wakeham, Andrew; You-Ten, Annick J.; McIlwain, David R.; Merches, Katja; Khairnar, Vishal; Recher, Mike; Nolan, Garry P.; Hitoshi, Yasumichi; Funkner, Pauline; Navarini, Alexander A.; Verschoor, Admar; Shaabani, Namir; Honke, Nadine; Penn, Linda Z.; Ohashi, Pamela S.; Häussinger, Dieter; Lee, Kyeong-Hee; Mak, Tak W.

    2013-01-01

    Rapid activation of immune responses is necessary for antibacterial defense, but excessive immune activation can result in life-threatening septic shock. Understanding how these processes are balanced may provide novel therapeutic potential in treating inflammatory disease. Fc receptors are crucial for innate immune activation. However, the role of the putative Fc receptor for IgM, known as Toso/Faim3, has to this point been unclear. In this study, we generated Toso-deficient mice and used them to uncover a critical regulatory function of Toso in innate immune activation. Development of innate immune cells was intact in the absence of Toso, but Toso-deficient neutrophils exhibited more reactive oxygen species production and reduced phagocytosis of pathogens compared with controls. Cytokine production was also decreased in Toso−/− mice compared with WT animals, rendering them resistant to septic shock induced by lipopolysaccharide. However, Toso−/− mice also displayed limited cytokine production after infection with the bacterium Listeria monocytogenes that was correlated with elevated presence of Listeria throughout the body. Accordingly, Toso−/− mice succumbed to infections of L. monocytogenes, whereas WT mice successfully eliminated the infection. Taken together, our data reveal Toso to be a unique regulator of innate immune responses during bacterial infection and septic shock. PMID:23359703

  10. Enhanced superoxide release and tumoricidal activity by a postlavage, in situ pulmonary macrophage population in response to activation by Mycobacterium bovis BCG exposure.

    PubMed Central

    Drath, D B

    1985-01-01

    The monocytic phagocyte population of rat lungs is heterogeneous. In addition to the freely lavagable alveolar macrophages, there is a fixed in situ tissue-associated subpopulation of pulmonary macrophages. The response of this subpopulation to classical macrophage activation by Mycobacterium bovis BCG exposure was monitored. Results indicate that this population can be activated both metabolically and functionally, as evidenced by enhanced release of superoxide anions and demonstrable tumoricidal activity against syngeneic and xenogeneic target cells. The pattern of metabolic activation of in situ tissue-associated macrophages differed somewhat from that of alveolar macrophages and was observed only after subsequent exposure of the cells to either zymosan particles or phorbol myristate acetate. Upon such exposure, the activated zymosan-treated tissue macrophages released approximately twice as much superoxide as the nonactivated cells and amounts comparable to the amounts released by activated alveolar macrophages. The tissue macrophages also displayed greater levels of cytotoxicity toward xenogenic targets than the alveolar cells and may have an important role in preventing microbial or tumor cell colonization of respiratory systems. PMID:2989181

  11. Enhanced superoxide release and tumoricidal activity by a postlavage, in situ pulmonary macrophage population in response to activation by Mycobacterium bovis BCG exposure.

    PubMed

    Drath, D B

    1985-07-01

    The monocytic phagocyte population of rat lungs is heterogeneous. In addition to the freely lavagable alveolar macrophages, there is a fixed in situ tissue-associated subpopulation of pulmonary macrophages. The response of this subpopulation to classical macrophage activation by Mycobacterium bovis BCG exposure was monitored. Results indicate that this population can be activated both metabolically and functionally, as evidenced by enhanced release of superoxide anions and demonstrable tumoricidal activity against syngeneic and xenogeneic target cells. The pattern of metabolic activation of in situ tissue-associated macrophages differed somewhat from that of alveolar macrophages and was observed only after subsequent exposure of the cells to either zymosan particles or phorbol myristate acetate. Upon such exposure, the activated zymosan-treated tissue macrophages released approximately twice as much superoxide as the nonactivated cells and amounts comparable to the amounts released by activated alveolar macrophages. The tissue macrophages also displayed greater levels of cytotoxicity toward xenogenic targets than the alveolar cells and may have an important role in preventing microbial or tumor cell colonization of respiratory systems. PMID:2989181

  12. LOX-1, mtDNA damage, and NLRP3 inflammasome activation in macrophages: implications in atherogenesis

    PubMed Central

    Ding, Zufeng; Liu, Shijie; Wang, Xianwei; Dai, Yao; Khaidakov, Magomed; Deng, Xiaoyan; Fan, Yubo; Xiang, David; Mehta, Jawahar L.

    2014-01-01

    Aims Lectin-like ox-LDL scavenger receptor-1 (LOX-1) and mitochondrial DNA (mtDNA) damage play a key role in a variety of cardiovascular diseases, including atherosclerosis, hypertension, and inflammation. We posited that damaged mtDNA could trigger autophagy and NLRP3 inflammasome activation, and LOX-1 may play a critical role in this process. Methods and results In order to examine this hypothesis, cultured human THP-1 macrophages exposed to lipopolysaccharide (LPS) were applied to study the link between LOX-1, mtDNA damage, autophagy, and NLRP3 inflammasome expression. Our data showed that LPS markedly induced LOX-1 expression, reactive oxygen species (ROS) generation, autophagy, mtDNA damage, and NLRP3 inflammasome. LOX-1 inhibition with a binding antibody or siRNA inhibited ROS generation, autophagy and mtDNA damage, and a decreased expression of NLRP3 inflammasome. To study the LOX-1–NLRP3 inflammasome signalling, we performed studies using ROS inhibitors and an autophagy inducer, and found that both decreased the expression of NLRP3. On the other hand, autophagy inhibitor enhanced the expression of NLRP3 inflammasome. Knockdown of DNase II inhibited autophagy and NLRP3 inflammasome, providing further support for our hypothesis. Finally, we confirmed the relationship between LOX-1, ROS, mtDNA damage, autophagy, and NLRP3 inflammasome activation in primary macrophages. Conclusions This study based on THP-1 macrophages and primary macrophages indicates that LOX-1-mediated autophagy and mtDNA damage play an essential role in NLRP3 inflammasome activation in inflammatory disease states. PMID:24776598

  13. Autocrine regulation of macrophage activation via exocytosis of ATP and activation of P2Y11 receptor.

    PubMed

    Sakaki, Hayato; Tsukimoto, Mitsutoshi; Harada, Hitoshi; Moriyama, Yoshinori; Kojima, Shuji

    2013-01-01

    It is important to understand the mechanisms that regulate macrophage activation to establish novel therapies for inflammatory diseases, such as sepsis; a systemic inflammatory response syndrome generally caused by bacterial lipopolysaccharide (LPS). In this study, we investigated the involvement of extracellular ATP-mediated autocrine signaling in LPS-induced macrophage activation. We show here that ATP release via exocytosis, followed by activation of P2Y11 receptor, is a major pathway of the macrophage activation, leading to release of cytokines. Treatment of human monocyte THP-1 cells with LPS induced rapid ATP release from cells, and this release was blocked by knockdown of SLC17A9 (vesicular nucleotide transporter, VNUT), which is responsible for exocytosis of ATP. ATP-enriched vesicles were found in cytosol of THP-1 cells. These data suggest the involvement of vesicular exocytosis in the release of ATP. Knockdown of SLC17A9, the P2Y11 antagonist NF157 or knockdown of P2Y11 receptor significantly suppressed both M1-type polarization and IL-6 production in THP-1 cells, indicating an important role of activation of P2Y11 receptor by released ATP in macrophage activation. Next, the effect of NF157 on LPS-induced immune activation was examined in vivo. Administration of LPS to mice caused increase of serum IL-1ß, IL-6, IL-12 and TNF-alpha levels at 3-24 h after the administration. Pre-treatment of LPS-treated mice with NF157 suppressed both elevation of proinflammatory cytokines in serum and M1 polarization of peritoneal/spleen macrophages. Moreover, post-treatment with NF157 at 30 min after administration of LPS also suppressed the elevation of serum cytokines levels. We conclude that vesicular exocytosis of ATP and autocrine, positive feedback through P2Y11 receptors is required for the effective activation of macrophages. Consequently, P2Y11 receptor antagonists may be drug candidates for treatment of inflammatory diseases such as sepsis. PMID:23577075

  14. Genome-wide analysis of antiviral signature genes in porcine macrophages at different activation statuses.

    PubMed

    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

  15. 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

  16. Interleukin 10 inhibits macrophage microbicidal activity by blocking the endogenous production of tumor necrosis factor alpha required as a costimulatory factor for interferon gamma-induced activation.

    PubMed Central

    Oswald, I P; Wynn, T A; Sher, A; James, S L

    1992-01-01

    Interleukin 10 (IL-10) inhibits interferon gamma-induced macrophage activation for cytotoxicity against larvae of the human parasite Schistosoma mansoni by suppressing production of the toxic effector molecule nitric oxide (NO). In this study, the mechanism of IL-10 action was identified as inhibition of endogenous tumor necrosis factor alpha (TNF-alpha) production by interferon gamma-activated macrophages. TNF-alpha appears to serve as a cofactor for interferon gamma-mediated activation, since both schistosomulum killing and NO production were inhibited by anti-TNF-alpha antibody, whereas TNF-alpha alone was unable to stimulate these macrophage functions. IL-10 blocked TNF-alpha production by interferon gamma-treated macrophages at the levels of both protein and mRNA synthesis. Addition of exogenous TNF-alpha reversed IL-10-mediated suppression of macrophage cytotoxic activity as well as NO production. Likewise, addition of a macrophage-triggering agent (bacterial lipopolysaccharide or muramyl dipeptide), which induced the production of TNF-alpha, also reversed the suppressive effect of IL-10 on cytotoxic function. In contrast to IL-10, two other cytokines, IL-4 and transforming growth factor beta, which also inhibit macrophage activation for schistosomulum killing and NO production, did not substantially suppress endogenous TNF-alpha production. These results, therefore, describe a separate pathway by which macrophage microbicidal function is inhibited by the down-regulatory cytokine IL-10. Images PMID:1528880

  17. Estrogen Represses Hepatocellular Carcinoma (HCC) Growth via Inhibiting Alternative Activation of Tumor-associated Macrophages (TAMs)*

    PubMed Central

    Yang, Weiwei; Lu, Yan; Xu, Yichen; Xu, Lizhi; Zheng, Wei; Wu, Yuanyuan; Li, Long; Shen, Pingping

    2012-01-01

    Hepatocarcinoma cancer (HCC), one of the most malignant cancers, occurs significantly more often in men than in women; however, little is known about its underlying molecular mechanisms. Here we identified that 17β-estradiol (E2) could suppress tumor growth via regulating the polarization of macrophages. We showed that E2 re-administration reduced tumor growth in orthotopic and ectopic mice HCC models. E2 functioned as a suppressor for macrophage alternative activation and tumor progression by keeping estrogen receptor β (ERβ) away from interacting with ATP5J (also known as ATPase-coupling factor 6), a part of ATPase, thus inhibiting the JAK1-STAT6 signaling pathway. These studies introduce a novel mechanism for suppressing male-predominant HCC. PMID:22908233

  18. Autocrine abscisic acid plays a key role in quartz-induced macrophage activation.

    PubMed

    Magnone, Mirko; Sturla, Laura; Jacchetti, Emanuela; Scarfì, Sonia; Bruzzone, Santina; Usai, Cesare; Guida, Lucrezia; Salis, Annalisa; Damonte, Gianluca; De Flora, Antonio; Zocchi, Elena

    2012-03-01

    Inhalation of quartz induces silicosis, a lung disease where alveolar macrophages release inflammatory mediators, including prostaglandin-E(2) (PGE(2)) and tumor necrosis factor α (TNF-α). Here we report the pivotal role of abscisic acid (ABA), a recently discovered human inflammatory hormone, in silica-induced activation of murine RAW264.7 macrophages and of rat alveolar macrophages (AMs). Stimulation of both RAW264.7 cells and AMs with quartz induced a significant increase of ABA release (5- and 10-fold, respectively), compared to untreated cells. In RAW264.7 cells, autocrine ABA released after quartz stimulation sequentially activates the plasma membrane receptor LANCL2 and NADPH oxidase, generating a Ca(2+) influx resulting in NFκ B nuclear translocation and PGE(2) and TNF-α release (3-, 2-, and 3.5-fold increase, respectively, compared to control, unstimulated cells). Quartz-stimulated RAW264.7 cells silenced for LANCL2 or preincubated with a monoclonal antibody against ABA show an almost complete inhibition of NFκ B nuclear translocation and PGE(2) and TNF-α release compared to controls electroporated with a scramble oligonucleotide or preincubated with an unrelated antibody. AMs showed similar early and late ABA-induced responses as RAW264.7 cells. These findings identify ABA and LANCL2 as key mediators in quartz-induced inflammation, providing possible new targets for antisilicotic therapy. PMID:22042223

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

    PubMed Central

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

    2014-01-01

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

  20. Vitamin D Is Required for IFN-γ–Mediated Antimicrobial Activity of Human Macrophages

    PubMed Central

    Fabri, Mario; Stenger, Steffen; Shin, Dong-Min; Yuk, Jae-Min; Liu, Philip T.; Realegeno, Susan; Lee, Hye-Mi; Krutzik, Stephan R.; Schenk, Mirjam; Sieling, Peter A.; Teles, Rosane; Montoya, Dennis; Iyer, Shankar S.; Bruns, Heiko; Lewinsohn, David M.; Hollis, Bruce W.; Hewison, Martin; Adams, John S.; Steinmeyer, Andreas; Zügel, Ulrich; Cheng, Genhong; Jo, Eun-Kyeong; Bloom, Barry R.; Modlin, Robert L.

    2012-01-01

    Control of tuberculosis worldwide depends on our understanding of human immune mechanisms, which combat the infection. Acquired T cell responses are critical for host defense against microbial pathogens, yet the mechanisms by which they act in humans remain unclear. We report that T cells, by the release of interferon-γ (IFN-γ), induce autophagy, phagosomal maturation, the production of antimicrobial peptides such as cathelicidin, and antimicrobial activity against Mycobacterium tuberculosis in human macrophages via a vitamin D–dependent pathway. IFN-γ induced the antimicrobial pathway in human macrophages cultured in vitamin D–sufficient sera, but not in sera from African-Americans that have lower amounts of vitamin D and who are more susceptible to tuberculosis. In vitro supplementation of vitamin D–deficient serum with 25-hydroxyvitamin D3 restored IFN-γ–induced antimicrobial peptide expression, autophagy, phagosome-lysosome fusion, and antimicrobial activity. These results suggest a mechanism in which vitamin D is required for acquired immunity to overcome the ability of intracellular pathogens to evade macrophage-mediated antimicrobial responses. The present findings underscore the importance of adequate amounts of vitamin D in all human populations for sustaining both innate and acquired immunity against infection. PMID:21998409

  1. Candida albicans actively modulates intracellular membrane trafficking in mouse macrophage phagosomes.

    PubMed

    Fernández-Arenas, Elena; Bleck, Christopher K E; Nombela, César; Gil, Concha; Griffiths, Gareth; Diez-Orejas, Rosalía

    2009-04-01

    The intracellular trafficking/survival strategies of the opportunistic human pathogen Candida albicans are poorly understood. Here we investigated the infection of RAW264.7 macrophages with a virulent wild-type (WT) filamentous C. albicans strain and a hyphal signalling-defective mutant (efg1Delta/cph1Delta). A comparative analysis of the acquisition by phagosomes of actin, and of early/late endocytic organelles markers of the different fungal strains was performed and related to Candida's survival inside macrophages. Our results show that both fungal strains have evolved a similar mechanism to subvert the 'lysosomal' system, as seen by the inhibition of the phagosome fusion with compartments enriched in the lysobisphosphatidic acid and the vATPase, and thereby the acquisition of a low pH from the outset of infection. Besides, the virulent WT strain displayed additional specific survival strategies to prevent its targeting to compartmentsdisplaying late endosomal/lysosomal features, such as induction of active recycling out of phagosomes of the lysosomal membrane protein LAMP-1, the lysosomal protease cathepsin D and preinternalized colloidal gold. Finally, both virulent and efg1Delta/cph1Delta mutant fungal strains actively suppressed the production of macrophage nitric oxide (NO), although their cell wall extracts were potent inducers of NO. PMID:19134116

  2. Regulation of 3-hydroxy-3-methylglutaryl-coenzyme A reductase activity in mouse peritoneal macrophages.

    PubMed Central

    Angelin, B

    1988-01-01

    The lipoprotein-mediated regulation of 3-hydroxy-3-methylglutaryl-(HMG-) CoA reductase in cultured mouse peritoneal macrophages has been investigated. In contrast to what has been reported for other cells, HMG-CoA reductase activity is not suppressed by normal serum or by normal low density lipoproteins (LDL) from humans or dogs. Suppression of reductase activity occurred when cells were cultured in the presence of beta-migrating very low density lipoproteins (beta-VLDL) or LDL from hypercholesterolaemic dogs, or LDL modified by acetoacetylation. Human beta-VLDL from an atypical type III hyperlipoproteinaemic patient was also effective, as was apolipoprotein (apo) E-containing high density lipoproteins (HDL) from cholesterol-fed dogs (apo-E HDLc). The results indicate that cholesterol biosynthesis in mouse peritoneal macrophages is regulated by lipoprotein cholesterol entering via receptor-mediated endocytosis. Normal LDL were not effective because of the poor binding and uptake of these lipoproteins by the apo-B, E (LDL) receptor. Only beta-VLDL, apo-E HDLc, and hypercholesterolaemic LDL were avidly taken up by this receptor and were able to suppress HMG-CoA reductase. Acetoacetylated LDL were internalized via the acetyl-LDL (scavenger) receptor. Thus, mouse macrophages differ from human fibroblasts and smooth muscle cells in their physiological regulation of cholesterogenesis. PMID:3202831

  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. Effect of immunochemotherapy with OK-432 and yeast cell wall on the activities of peritoneal macrophages of mice.

    PubMed

    Mashiba, H; Matsunaga, K; Gojobori, M

    1979-10-01

    The effect of chemotherapy combined with immunostimulants on the activities of macrophages in mice was studied. The number of macrophages and exudate cells in the peritoneal cavity increased 3 days after ip injection with mitomycin-C, cyclophosphamide, and 5-fluorouracil together with OK-432 or yeast cell wall and decreased to normal level after 9 days, while the number of the cells remained decreased in mice receiving multi-drugs alone. Acid phosphatase activity of the macrophages of mice was elevated after the simultaneous injection of yeast cell wall and OK-432, and high activity was preserved in the macrophages of mice receiving yeast cell wall even after 9 days. Spreading of these cells was also enhanced. Macrophage activities examined by these assays were maximal in every respect 6 days after combination therapy. Cytostatic activity of the cells was strengthened after 6 days by combined use of OK-432 or yeast cell wall. Role of the activated macrophages in combination therapy was discussed. PMID:520759

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

    PubMed Central

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

    2015-01-01

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

  6. Patient specific proteolytic activity of monocyte-derived macrophages and osteoclasts predicted with temporal kinase activation states during differentiation

    PubMed Central

    Park, Keon-Young; Li, Weiwei A.; Platt, Manu O.

    2012-01-01

    Patient-to-patient variability in disease progression continues to complicate clinical decisions of treatment regimens for cardiovascular diseases, metastatic cancers and osteoporosis. Here, we investigated if monocytes, circulating white blood cells that enter tissues and contribute to disease progression by differentiating into macrophages or osteoclasts, could be useful in understanding this variability. Monocyte-derived macrophages and osteoclasts produce cysteine cathepsins, powerful extracellular matrix proteases which have been mechanistically linked to accelerated atherosclerotic, osteoporotic, and tumor progression. We hypothesized that multivariate analysis of temporal kinase activation states during monocyte differentiation could predict cathepsin proteolytic responses of monocyte-derived macrophages and osteoclasts in a patient-specific manner. Freshly isolated primary monocytes were differentiated with M-CSF or RANKL into macrophages or osteoclasts, respectively, and phosphorylation of ERK1/2, Akt, p38 MAPK, JNK, c-jun, and IκB-α were measured at days 1, 3, 6, and 9. In parallel, cell diameters and numbers of nuclei were measured, and multiplex cathepsin zymography was used to quantify cathepsins K, L, S, and V activity from cell extracts and conditioned media. There was extensive patient-to-patient variability in temporal kinase activation states, cell morphologies, and cathepsin K, L, S, and V proteolytic activity. Partial least squares regression models trained with temporal kinase activation states successfully predicted patient-specific morphological characteristics (mean cell diameter and number of nuclei) and patient-specific cathepsin proteolytic activity with predictability as high as 95%, even with the challenge of incorporating the complex, unknown cues from individual patients’ unique genetic and biochemical backgrounds. This personalized medicine approach considers patient variability in kinase signals to predict cathepsin activity

  7. Immunopharmacological activity of Echinacea preparations following simulated digestion on murine macrophages and human peripheral blood mononuclear cells.

    PubMed

    Rininger, J A; Kickner, S; Chigurupati, P; McLean, A; Franck, Z

    2000-10-01

    We have investigated the immunostimulatory, anti-inflammatory, and antioxidant activities of various Echinacea raw materials and commercially available products on murine macrophages and human peripheral blood mononuclear cells (PBMCs). To emulate oral dosing, a simulated digestion protocol was employed as a means of sample preparation. Echinacea-induced macrophage activation was used as a measure of immunostimulatory activity determined via quantitative assays for macrophage-derived factors including tumor necrosis factor alpha, interleukin (IL)-1alpha, IL-1beta, IL-6, IL-10, and nitric oxide. Echinacea herb and root powders were found to stimulate murine macrophage cytokine secretion as well as to significantly enhance the viability and/or proliferation of human PBMCs in vitro. In contrast, Echinacea extracts chemically standardized to phenolic acid or echinacoside content and fresh pressed juice preparations were found to be inactive as immunostimulatory agents but did display, to varying degrees, anti-inflammatory and antioxidant properties. PMID:11037971

  8. Suppressor of cytokine signaling 3 inhibits head kidney macrophage activation and cytokine expression in Scophthalmus maximus.

    PubMed

    Zhang, Min; Xiao, Zhi-zhong; Sun, Li

    2011-02-01

    Proteins of the suppressor of cytokine signaling (SOCS) family function as inducible feedback inhibitors of cytokine signaling via the JAK/STAT pathway. Although several SOCS isoforms have been identified in teleosts, their immunological functions remain largely unknown. In this study, we identified in turbot Scophthalmus maximus a SOCS homologue (named SmSOCS3) of the mammalian SOCS3 type. The deduced amino acid sequence of SmSOCS3 contains 205 residues and shares extensive overall identities (60-82%) with those of known fish SOCS3. In silico analyses revealed that, like typical SOCS3, SmSOCS3 possesses a kinase inhibitor region (KIR), a Src homology 2 (SH2) domain, and a SOCS box domain. Under physiological conditions SmSOCS3 expression was detected, in increasing order, in blood, brain, heart, kidney, liver, spleen, muscle, and gill. Experimental infection of turbot with a bacterial pathogen induced significant SmSOCS3 expression in kidney, spleen, liver, and gill in time-dependent manners. Examination of SmSOCS3 expression in head kidney (HK) macrophages showed that SmSOCS3 transcription was significantly upregulated in the presence of purified recombinant TNF-α. On the other hand, SmSOCS3 overexpression in HK macrophages inhibited the transcription of TNF-α as well as IL-1β and CC-chemokine. In addition, SmSOCS3 overexpression significantly reduced macrophage respiratory burst activity, nitric oxide production, and bactericidal activity. Taken together, these results suggest that SmSOCS3 is a cytokine-inducible suppressor of pro-inflammatory cytokine signaling in HK macrophages and that regulated expression of SmSOCS3 is required for optimal innate immune response against bacterial infection. PMID:20869394

  9. A Potent Systemically Active N-Acylethanolamine Acid Amidase Inhibitor that Suppresses Inflammation and Human Macrophage Activation.

    PubMed

    Ribeiro, Alison; Pontis, Silvia; Mengatto, Luisa; Armirotti, Andrea; Chiurchiù, Valerio; Capurro, Valeria; Fiasella, Annalisa; Nuzzi, Andrea; Romeo, Elisa; Moreno-Sanz, Guillermo; Maccarrone, Mauro; Reggiani, Angelo; Tarzia, Giorgio; Mor, Marco; Bertozzi, Fabio; Bandiera, Tiziano; Piomelli, Daniele

    2015-08-21

    Fatty acid ethanolamides such as palmitoylethanolamide (PEA) and oleoylethanolamide (OEA) are lipid-derived mediators that potently inhibit pain and inflammation by ligating type-α peroxisome proliferator-activated receptors (PPAR-α). These bioactive substances are preferentially degraded by the cysteine hydrolase, N-acylethanolamine acid amidase (NAAA), which is highly expressed in macrophages. Here, we describe a new class of β-lactam derivatives that are potent, selective, and systemically active inhibitors of intracellular NAAA activity. The prototype of this class deactivates NAAA by covalently binding the enzyme's catalytic cysteine and exerts profound anti-inflammatory effects in both mouse models and human macrophages. This agent may be used to probe the functions of NAAA in health and disease and as a starting point to discover better anti-inflammatory drugs. PMID:25874594

  10. 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. PMID:22967923

  11. Phagocytosis-induced 51Cr release from activated macrophages and blood mononuclears. Effect of colchicine and antioxidants

    SciTech Connect

    McGee, M.P.; Hale, A.H.

    1981-09-01

    The chromium-release test was adapted to the measurement of the cellular injury induced when activated macrophages phagocytose particulates. Macrophages obtained from rabbit lungs undergoing BCG-induced chronic inflammation released more chromium when incubated in the presence of phagocytosable particles than when incubated under resting conditions. Blood mononuclear cells, 40-60% monocytes, procured from the same BCG-injected animals, were less susceptible to phagocytosis-induced injury than the macrophages obtained from the lungs. The amount of chromium released by the activated macrophages was proportional to the number of particles present during incubation. In the presence of catalase, the amounts of chromium released by phagocytosing and resting macrophages were similar; in the presence of superoxide dismutase and cytochrome c, the amount of chromium released by phagocytosing macrophages was 13-35% less than the amount of chromium released by macrophages incubated without the antioxidants. In addition, colchicine, an inhibitor of degranulation also exerted partial inhibition of the chromium release. These results suggest that oxygen radicals and lysosomal contents contribute to the cellular injury that results from phagocytosis.

  12. Macrophage-mediated osteogenesis activation in co-culture with osteoblast on calcium silicate cement.

    PubMed

    Tu, Ming-Gene; Chen, Yi-Wen; Shie, Ming-You

    2015-12-01

    The use of calcium silicate (CS) cement holds great promise for bone substitute biomaterials. However, the effects of CS on osteoblast and macrophage cells are not fully understood. This study examines cell proliferation and differentiation of mono- or co-cultured MC3T3-E1 and Raw 264.7 cells on CS cement. Very few studies to date have looked at the effects of osteoblast and macrophages on biomaterial-regulated osteogenesis. In this study the proliferation and differentiation of MC3T3-E1, Raw 264.7 and co-cultured MC3T3-E1/Raw 264.7 on CS cements have been analyzed using a PrestoBlue kit and ELISA. In addition, the effect of macrophages on CS-coordinated osteogenesis of MC3T3-E1 has been investigated. Results show that MC3T3-E1, Raw 264.7 and co-cultured MC3T3-E1/Raw 264.7 adhere to and proliferate well on the CS cement. In a co-culture, the CS cements inhibit receptor activator of nuclear factor kappa B ligand expression of both genes and proteins in Raw 264.7 cells when compared to those grown in mono-cultured system. Ca deposition of MC3T3-E1 in the co-culture is higher than that of cells in a mono-culture. Bone morphogenetic protein 2 (BMP2) is also significantly up-regulated by the CS cement stimulation, indicating that macrophages may participate in the CS stimulated osteogenesis. Interestingly, when macrophage are cultured with BMP2 receptor-blocking MC3T3-E1 on the CS cements, the osteogenesis differentiation of the cells is significantly inhibited, indicating the important role of macrophages in biomaterial-induced osteogenesis via BMP2 receptors. It is assumed that it is an increase in the secretion of the BMP2 from the Raw 264.7 cell that is primarily involved in the promotion of the osteogenesis of the MC3T3-E1. These results provide valuable insights into both the mechanism of CS-stimulated osteogenesis, and strategies to optimize the evaluation system for the in vitro osteogenesis capacity of bone substitute biomaterials. PMID:26543022

  13. Macrophage-derived neutrophil chemotactic factor is involved in the neutrophil recruitment inhibitory activity present in the supernatants of LPS-stimulated macrophages

    PubMed Central

    Tavares-Murta, B. M.; Cunha, F. Q.; Dias-Baruffi, M.; Roque-Barreira, M. C.

    1996-01-01

    In a previous study, we demonstrated the presence of a neutrophil recruitment inhibitory factor (NRIF) in the supernatants of LPS-stimulated macrophages. Recently, the purification of a 54 kDa protein, identified as the macrophage-derived neutrophil chemotactic factor (MNCF) was reported. Since NRIF and MNCF are obtained under the same conditions, and, since the intravenous administration of TNF-α and IL-8 inhibits neutrophil migration, we have investigated whether MNCF could be responsible for this inhibitory activity. After affinity chromatography of the macrophage supernatants on a D-galactose column, the inhibitory activity was recovered in both the unbound (D-gal−) and bound (D-gal+) fractions, with MNCF being found in the D-gal+ fraction. Further gel filtration of the latter on Superdex 75 yielded a single peak containing both activities. In a cytotoxicity assay, most of the TNF found in the crude supernatants was recovered in the D-gal− fraction. Furthermore, the incubation of the D-gal− fraction with anti-TNF-α plus anti-IL-8 antisera partially prevents its inhibitory effect on neutrophil migration, but had no effect on the D-gal+ activity. Overall, these results suggest that the D-gal− inhibitory effect is partially mediated by TNF-α and IL-8, and that MNCF accounts for the inhibition of neutrophil migration in vivo by the D-gal+ fraction. PMID:18475709

  14. Structurally well-defined macrophage activating factor derived from vitamin D3-binding protein has a potent adjuvant activity for immunization.

    PubMed

    Yamamoto, N; Naraparaju, V R

    1998-06-01

    Freund's adjuvant produced severe inflammation that augments development of antibodies. Thus, mixed administration of antigens with adjuvant was not required as long as inflammation was induced in the hosts. Since macrophage activation for phagocytosis and antigen processing is the first step of antibody development, inflammation-primed macrophage activation plays a major role in immune development. Therefore, macrophage activating factor should act as an adjuvant for immunization. The inflammation-primed macrophage activation process is the major macrophage activating cascade that requires participation of serum vitamin D3-binding protein (DBP; human DBP is known as Gc protein) and glycosidases of B and T lymphocytes. Stepwise incubation of Gc protein with immobilized beta-galactosidase and sialidase efficiently generated the most potent macrophage activating factor (designated GcMAF) we have ever encountered. Administration of GcMAF (20 or 100 pg/mouse) resulted in stimulation of the progenitor cells for extensive mitogenesis and activation of macrophages. Administration of GcMAF (100 pg/mouse) along with immunization of mice with sheep red blood cells (SRBC) produced a large number of anti-SRBC antibody secreting splenic cells in 2-4 days. Thus, GcMAF has a potent adjuvant activity for immunization. Although malignant tumours are poorly immunogenic, 4 days after GcMAF-primed immunization of mice with heat-killed Ehrlich ascites tumour cells, the ascites tumour was no longer transplantable in these mice. PMID:9682967

  15. 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

  16. A Novel Polysaccharide in Insects Activates the Innate Immune System in Mouse Macrophage RAW264 Cells

    PubMed Central

    Ohta, Takashi; Ido, Atsushi; Kusano, Kie; Miura, Chiemi; Miura, Takeshi

    2014-01-01

    A novel water-soluble polysaccharide was identified in the pupae of the melon fly (Bactrocera cucurbitae) as a molecule that activates the mammalian innate immune response. We attempted to purify this innate immune activator using nitric oxide (NO) production in mouse RAW264 macrophages as an indicator of immunostimulatory activity. A novel acidic polysaccharide was identified, which we named “dipterose”, with a molecular weight of 1.01×106 and comprising nine monosaccharides. Dipterose was synthesized in the melon fly itself at the pupal stage. The NO-producing activity of dipterose was approximately equal to that of lipopolysaccharide, a potent immunostimulator. Inhibition of Toll-like receptor 4 (TLR4) led to the suppression of NO production by dipterose. Furthermore, dipterose induced the expression of proinflammatory cytokines and interferon β (IFNβ) and promoted the activation of nuclear factor kappa B (NF-κB) in macrophages, indicating that it stimulates the induction of various cytokines in RAW264 cells via the TLR4 signaling pathway. Our results thus suggest that dipterose activates the innate immune response against various pathogenic microorganisms and viral infections. This is the first identification of an innate immune-activating polysaccharide from an animal. PMID:25490773

  17. Expression of inducible nitric oxide synthase by stimulated macrophages correlates with their antihistoplasma activity.

    PubMed Central

    Lane, T E; Otero, G C; Wu-Hsieh, B A; Howard, D H

    1994-01-01

    The antihistoplasma activity of recombinant murine gamma interferon (rMuIFN-gamma)-treated macrophages of the RAW 264.7 cell line depends on the generation of nitric oxide (NO.) from L-arginine. Macrophages of the P388D1 cell line treated with rMuIFN-gamma do not produce NO. or inhibit the intracellular growth of Histoplasma capsulatum. NO. is generated by the inducible enzyme nitric oxide synthase (iNOS) formed by stimulated macrophages. Northern (RNA) blot analysis of RAW 264.7 cells revealed the expression of iNOS mRNA after exposure to rMuIFN-gamma. In contrast, rMuIFN-gamma-treated P388D1 cells did not produce detectable levels of iNOS. These data suggest that the failure of P388D1 cells to generate NO. and to restrict the intracellular growth of H. capsulatum is due to a lack of expression of iNOS following treatment with rMuIFN-gamma. Images PMID:7510670

  18. MicroRNAs Constitute a Negative Feedback Loop in Streptococcus pneumoniae-Induced Macrophage Activation.

    PubMed

    Griss, Kathrin; Bertrams, Wilhelm; Sittka-Stark, Alexandra; Seidel, Kerstin; Stielow, Christina; Hippenstiel, Stefan; Suttorp, Norbert; Eberhardt, Martin; Wilhelm, Jochen; Vera, Julio; Schmeck, Bernd

    2016-07-15

    Streptococcus pneumoniae causes high mortality as a major pneumonia-inducing pathogen. In pneumonia, control of innate immunity is necessary to prevent organ damage. We assessed the role of microRNAs (miRNAs) as regulators in pneumococcal infection of human macrophages. Exposure of primary blood-derived human macrophages with pneumococci resulted in transcriptional changes in several gene clusters and a significant deregulation of 10 microRNAs. Computational network analysis retrieved miRNA-146a as one putatively important regulator of pneumococci-induced host cell activation. Its induction depended on bacterial structural integrity and was completely inhibited by blocking Toll-like receptor 2 (TLR-2) or depleting its mediator MyD88. Furthermore, induction of miRNA-146a release did not require the autocrine feedback of interleukin 1β and tumor necrosis factor α released from infected macrophages, and it repressed the TLR-2 downstream mediators IRAK-1 and TRAF-6, as well as the inflammatory factors cyclooxygenase 2 and interleukin 1β. In summary, pneumococci recognition induces a negative feedback loop, preventing excessive inflammation via miR-146a and potentially other miRNAs. PMID:26984146

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

    PubMed Central

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

    2015-01-01

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

  20. SP-R210 (Myo18A) Isoforms as Intrinsic Modulators of Macrophage Priming and Activation

    PubMed Central

    DiAngelo, Susan L.; Silveyra, Patricia; Umstead, Todd M.; Halstead, E. Scott; Davies, Michael L.; Hu, Sanmei; Floros, Joanna; McCormack, Francis X.; Christensen, Neil D.; Chroneos, Zissis C.

    2015-01-01

    The surfactant protein (SP-A) receptor SP-R210 has been shown to increase phagocytosis of SP-A-bound pathogens and to modulate cytokine secretion by immune cells. SP-A plays an important role in pulmonary immunity by enhancing opsonization and clearance of pathogens and by modulating macrophage inflammatory responses. Alternative splicing of the Myo18A gene results in two isoforms: SP-R210S and SP-R210L, with the latter predominantly expressed in alveolar macrophages. In this study we show that SP-A is required for optimal expression of SP-R210L on alveolar macrophages. Interestingly, pre-treatment with SP-A prepared by different methods either enhances or suppresses responsiveness to LPS, possibly due to differential co-isolation of SP-B or other proteins. We also report that dominant negative disruption of SP-R210L augments expression of receptors including SR-A, CD14, and CD36, and enhances macrophages’ inflammatory response to TLR stimulation. Finally, because SP-A is known to modulate CD14, we used a variety of techniques to investigate how SP-R210 mediates the effect of SP-A on CD14. These studies revealed a novel physical association between SP-R210S, CD14, and SR-A leading to an enhanced response to LPS, and found that SP-R210L and SP-R210S regulate internalization of CD14 via distinct macropinocytosis-like mechanisms. Together, our findings support a model in which SP-R210 isoforms differentially regulate trafficking, expression, and activation of innate immune receptors on macrophages. PMID:25965346

  1. Pneumolysin Activates Macrophage Lysosomal Membrane Permeabilization and Executes Apoptosis by Distinct Mechanisms without Membrane Pore Formation

    PubMed Central

    Bewley, Martin A.; Naughton, Michael; Preston, Julie; Mitchell, Andrea; Holmes, Ashleigh; Marriott, Helen M.; Read, Robert C.; Mitchell, Timothy J.; Whyte, Moira K. B.

    2014-01-01

    ABSTRACT Intracellular killing of Streptococcus pneumoniae is complemented by induction of macrophage apoptosis. Here, we show that the toxin pneumolysin (PLY) contributes both to lysosomal/phagolysosomal membrane permeabilization (LMP), an upstream event programing susceptibility to apoptosis, and to apoptosis execution via a mitochondrial pathway, through distinct mechanisms. PLY is necessary but not sufficient for the maximal induction of LMP and apoptosis. PLY’s ability to induce both LMP and apoptosis is independent of its ability to form cytolytic pores and requires only the first three domains of PLY. LMP involves TLR (Toll-like receptor) but not NLRP3/ASC (nucleotide-binding oligomerization domain [Nod]-like receptor family, pyrin domain-containing protein 3/apoptosis-associated speck-like protein containing a caspase recruitment domain) signaling and is part of a PLY-dependent but phagocytosis-independent host response that includes the production of cytokines, including interleukin-1 beta (IL-1β). LMP involves progressive and selective permeability to 40-kDa but not to 250-kDa fluorescein isothiocyanate (FITC)-labeled dextran, as PLY accumulates in the cytoplasm. In contrast, the PLY-dependent execution of apoptosis requires phagocytosis and is part of a host response to intracellular bacteria that also includes NO generation. In cells challenged with PLY-deficient bacteria, reconstitution of LMP using the lysomotrophic detergent LeuLeuOMe favored cell necrosis whereas PLY reconstituted apoptosis. The results suggest that PLY contributes to macrophage activation and cytokine production but also engages LMP. Following bacterial phagocytosis, PLY triggers apoptosis and prevents macrophage necrosis as a component of a broad-based antimicrobial strategy. This illustrates how a key virulence factor can become the focus of a multilayered and coordinated innate response by macrophages, optimizing pathogen clearance and limiting inflammation. PMID:25293758

  2. Interaction of Nutrition and Infection: Macrophage Activity in Vitamin B12-Deficient Rats Infected with Trypanosoma Lewisi

    PubMed Central

    Thomaskutty, K. G.; Lee, C. M.

    1987-01-01

    Macrophage activity was studied in rats infected with Trypanosoma lewisi in three protocol groups: one group was fed complete diet, a second group was given a vitamin B12-deficient diet, and a third group was fed a pair-fed control (calorically restricted) diet. Throughout the observational period, in animals fed complete and pairfed diets, marked increases in acid phosphatase levels in peritoneal macrophages were directly related to the degree of parasitemia. Acid phosphatase levels in rats deprived of vitamin B12 were approximately one third that of animals with an adequate supply of the vitamin. Irrespective of the diets, the infection with T lewisi also elicited increased macrophage phagocytosis of polystyrene latex particles and macrophage spreading. Both of these activities occurred at a much slower rate in the vitamin B12-deficient animals. PMID:3295263

  3. Macrophage response to bacteria: induction of marked secretory and cellular activities by lipoteichoic acids.

    PubMed Central

    Keller, R; Fischer, W; Keist, R; Bassetti, S

    1992-01-01

    Lipoteichoic acids (LTAs) from various bacterial species, including Staphylococcus aureus, Streptococcus pyogenes, Streptococcus pneumoniae, Enterococcus faecalis, and Listeria monocytogenes, were examined for the ability to induce secretory and cellular responses in a pure population of bone marrow-derived mononuclear phagocytes. Some of the highly purified LTAs, in particular LTAs from Bacillus subtilis, S. pyogenes, E. faecalis, and Enterococcus hirae, were able to affect each of the macrophage parameters measured, i.e., reductive capacity, secretion of tumor necrosis factor and nitrite, and tumoricidal activity. As after stimulation with whole organisms or other bacterial products, secretion of tumor necrosis factor induced by these LTAs reached its maximum within the first few hours of the interaction, while secretion of nitrite and tumoricidal activity required 24 to 36 h for full expression. Other purified LTAs, i.e., LTAs from Streptococcus sanguis, S. pneumoniae, and L. monocytogenes, as well as lipomannan from Micrococcus luteus affected only some of these parameters, while native LTA from S. aureus was inactive. There was no obvious correlation between biological activity and chain length, kind of glycosyl substituents, glycolipid structures, or fatty acid composition of LTAs. Deacylation of LTAs resulted in a complete loss of activity, and deacylated LTAs did not impair the activity of their acylated counterparts, suggesting that acyl chains may be essential for binding of LTA to the cell surface. The results demonstrate that some LTA species are potent inducers of macrophage secretory and cellular activities. PMID:1500175

  4. SESN2/sestrin2 suppresses sepsis by inducing mitophagy and inhibiting NLRP3 activation in macrophages.

    PubMed

    Kim, Min-Ji; Bae, Soo Han; Ryu, Jae-Chan; Kwon, Younghee; Oh, Ji-Hwan; Kwon, Jeongho; Moon, Jong-Seok; Kim, Kyubo; Miyawaki, Atsushi; Lee, Min Goo; Shin, Jaekyoon; Kim, Young Sam; Kim, Chang-Hoon; Ryter, Stefan W; Choi, Augustine M K; Rhee, Sue Goo; Ryu, Ji-Hwan; Yoon, Joo-Heon

    2016-08-01

    Proper regulation of mitophagy for mitochondrial homeostasis is important in various inflammatory diseases. However, the precise mechanisms by which mitophagy is activated to regulate inflammatory responses remain largely unknown. The NLRP3 (NLR family, pyrin domain containing 3) inflammasome serves as a platform that triggers the activation of CASP1 (caspase 1) and secretion of proinflammatory cytokines. Here, we demonstrate that SESN2 (sestrin 2), known as stress-inducible protein, suppresses prolonged NLRP3 inflammasome activation by clearance of damaged mitochondria through inducing mitophagy in macrophages. SESN2 plays a dual role in inducing mitophagy in response to inflammasome activation. First, SESN2 induces "mitochondrial priming" by marking mitochondria for recognition by the autophagic machinery. For mitochondrial preparing, SESN2 facilitates the perinuclear-clustering of mitochondria by mediating aggregation of SQSTM1 (sequestosome 1) and its binding to lysine 63 (Lys63)-linked ubiquitins on the mitochondrial surface. Second, SESN2 activates the specific autophagic machinery for degradation of primed mitochondria via an increase of ULK1 (unc-51 like kinase 1) protein levels. Moreover, increased SESN2 expression by extended LPS (lipopolysaccharide) stimulation is mediated by NOS2 (nitric oxide synthase 2, inducible)-mediated NO (nitric oxide) in macrophages. Thus, Sesn2-deficient mice displayed defective mitophagy, which resulted in hyperactivation of inflammasomes and increased mortality in 2 different sepsis models. Our findings define a unique regulatory mechanism of mitophagy activation for immunological homeostasis that protects the host from sepsis. PMID:27337507

  5. 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

  6. 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

  7. Activation of Cytosolic Phospholipase A2α in Resident Peritoneal Macrophages by Listeria monocytogenes Involves Listeriolysin O and TLR2*

    PubMed Central

    Noor, Shahid; Goldfine, Howard; Tucker, Dawn E.; Suram, Saritha; Lenz, Laurel L.; Akira, Shizuo; Uematsu, Satoshi; Girotti, Milena; Bonventre, Joseph V.; Breuel, Kevin; Williams, David L.; Leslie, Christina C.

    2016-01-01

    Eicosanoid production by macrophages is an early response to microbial infection that promotes acute inflammation. The intracellular pathogen Listeria monocytogenes stimulates arachidonic acid release and eicosanoid production from resident mouse peritoneal macrophages through activation of group IVA cytosolic phospholipase A2 (cPLA2α). The ability of wild type L. monocytogenes (WTLM) to stimulate arachidonic acid release is partially dependent on the virulence factor listeriolysin O; however, WTLM and L. monocytogenes lacking listeriolysin O (ΔhlyLM) induce similar levels of cyclooxygenase 2. Arachidonic acid release requires activation of MAPKs by WTLM and ΔhlyLM. The attenuated release of arachidonic acid that is observed in TLR2−/− and MyD88−/− macrophages infected with WTLM and ΔhlyLM correlates with diminished MAPK activation. WTLM but not ΔhlyLM increases intracellular calcium, which is implicated in regulation of cPLA2α. Prostaglandin E2, prostaglandin I2, and leukotriene C4 are produced by cPLA2α+/+ but not cPLA2α−/− macrophages in response to WTLM and ΔhlyLM. Tumor necrosis factor (TNF)-α production is significantly lower in cPLA2α+/+ than in cPLA2α−/− macrophages infected with WTLM and ΔhlyLM. Treatment of infected cPLA2α+/+ macrophages with the cyclooxygenase inhibitor indomethacin increases TNFα production to the level produced by cPLA2α−/− macrophages implicating prostaglandins in TNFα down-regulation. Therefore activation of cPLA2α in macrophages may impact immune responses to L. monocytogenes. PMID:18083708

  8. Ras-dependent and -independent pathways target the mitogen-activated protein kinase network in macrophages.

    PubMed Central

    Büscher, D; Hipskind, R A; Krautwald, S; Reimann, T; Baccarini, M

    1995-01-01

    Mitogen-activated protein kinases (MAPKs) are activated upon a variety of extracellular stimuli in different cells. In macrophages, colony-stimulating factor 1 (CSF-1) stimulates proliferation, while bacterial lipopolysaccharide (LPS) inhibits cell growth and causes differentiation and activation. Both CSF-1 and LPS rapidly activate the MAPK network and induce the phosphorylation of two distinct ternary complex factors (TCFs), TCF/Elk and TCF/SAP. CSF-1, but not LPS, stimulated the formation of p21ras. GTP complexes. Expression of a dominant negative ras mutant reduced, but did not abolish, CSF-1-mediated stimulation of MEK and MAPK. In contrast, activation of the MEK kinase Raf-1 was Ras independent. Treatment with the phosphatidylcholine-specific phospholipase C inhibitor D609 suppressed LPS-mediated, but not CSF-1-mediated, activation of Raf-1, MEK, and MAPK. Similarly, down-regulation or inhibition of protein kinase C blocked MEK and MAPK induction by LPS but not that by CSF-1. Phorbol 12-myristate 13-acetate pretreatment led to the sustained activation of the Raf-1 kinase but not that of MEK and MAPK. Thus, activated Raf-1 alone does not support MEK/MAPK activation in macrophages. Phosphorylation of TCF/Elk but not that of TCF/SAP was blocked by all treatments that interfered with MAPK activation, implying that TCF/SAP was targeted by a MAPK-independent pathway. Therefore, CSF-1 and LPS target the MAPK network by two alternative pathways, both of which induce Raf-1 activation. The mitogenic pathway depends on Ras activity, while the differentiation signal relies on protein kinase C and phosphatidylcholine-specific phospholipase C activation. PMID:7799956

  9. 25-Hydroxycholesterol Activates the Integrated Stress Response to Reprogram Transcription and Translation in Macrophages*

    PubMed Central

    Shibata, Norihito; Carlin, Aaron F.; Spann, Nathanael J.; Saijo, Kaoru; Morello, Christopher S.; McDonald, Jeffrey G.; Romanoski, Casey E.; Maurya, Mano R.; Kaikkonen, Minna U.; Lam, Michael T.; Crotti, Andrea; Reichart, Donna; Fox, Jesse N.; Quehenberger, Oswald; Raetz, Christian R. H.; Sullards, M. Cameron; Murphy, Robert C.; Merrill, Alfred H.; Brown, H. Alex; Dennis, Edward A.; Fahy, Eoin; Subramaniam, Shankar; Cavener, Douglas R.; Spector, Deborah H.; Russell, David W.; Glass, Christopher K.

    2013-01-01

    25-Hydroxycholesterol (25OHC) is an enzymatically derived oxidation product of cholesterol that modulates lipid metabolism and immunity. 25OHC is synthesized in response to interferons and exerts broad antiviral activity by as yet poorly characterized mechanisms. To gain further insights into the basis for antiviral activity, we evaluated time-dependent responses of the macrophage lipidome and transcriptome to 25OHC treatment. In addition to altering specific aspects of cholesterol and sphingolipid metabolism, we found that 25OHC activates integrated stress response (ISR) genes and reprograms protein translation. Effects of 25OHC on ISR gene expression were independent of liver X receptors and sterol-response element-binding proteins and instead primarily resulted from activation of the GCN2/eIF2α/ATF4 branch of the ISR pathway. These studies reveal that 25OHC activates the integrated stress response, which may contribute to its antiviral activity. PMID:24189069

  10. Toll-like receptor activation of XBP1 regulates innate immune responses in macrophages

    PubMed Central

    Martinon, Fabio; Chen, Xi; Lee, Ann-Hwee; Glimcher, Laurie H.

    2011-01-01

    Sensors of pathogens, such as Toll-like receptors (TLRs), detect microbes to activate transcriptional programs that orchestrate adaptive responses to specific insults. Here we report that TLR4 and TLR2 specifically activated the endoplasmic reticulum (ER)-stress sensor kinase IRE1α and its downstream target, the transcription factor XBP1. Previously described XBP1 ER stress target genes were not induced by TLR signaling. Instead, TLR-activated XBP1 was required for optimal and sustained production of proinflammatory cytokines in macrophages. Consistent with this finding, IRE1α activation by ER-stress synergized with TLR activation for cytokine production. Moreover, XBP1 deficiency markedly increased bacterial burden in animals infected with the TLR2-activating human pathogen Francisella tularensis. Our findings uncover an unsuspected critical new function for the XBP1 transcription factor in mammalian host defenses. PMID:20351694

  11. Macrophage- and RIP3-dependent inflammasome activation exacerbates retinal detachment-induced photoreceptor cell death

    PubMed Central

    Kataoka, K; Matsumoto, H; Kaneko, H; Notomi, S; Takeuchi, K; Sweigard, J H; Atik, A; Murakami, Y; Connor, K M; Terasaki, H; Miller, J W; Vavvas, D G

    2015-01-01

    Detachment of photoreceptors from the retinal pigment epithelium is seen in various retinal disorders, resulting in photoreceptor death and subsequent vision loss. Cell death results in the release of endogenous molecules that activate molecular platforms containing caspase-1, termed inflammasomes. Inflammasome activation in retinal diseases has been reported in some cases to be protective and in others to be detrimental, causing neuronal cell death. Moreover, the cellular source of inflammasomes in retinal disorders is not clear. Here, we demonstrate that patients with photoreceptor injury by retinal detachment (RD) have increased levels of cleaved IL-1β, an end product of inflammasome activation. In an animal model of RD, photoreceptor cell death led to activation of endogenous inflammasomes, and this activation was diminished by Rip3 deletion. The major source of Il1b expression was found to be infiltrating macrophages in the subretinal space, rather than dying photoreceptors. Inflammasome inhibition attenuated photoreceptor death after RD. Our data implicate the infiltrating macrophages as a source of damaging inflammasomes after photoreceptor detachment in a RIP3-dependent manner and suggest a novel therapeutic target for treatment of retinal diseases. PMID:25906154

  12. Bone marrow-derived macrophages exclusively expressed caveolin-2: The role of inflammatory activators and hypoxia.

    PubMed

    Maceckova, Michaela; Martiskova, Hana; Koudelka, Adolf; Kubala, Lukas; Lojek, Antonin; Pekarova, Michaela

    2015-11-01

    Caveolins are specific proteins involved in regulation of signal transduction to intracellular space. Still, their contribution to immune functions has not been completely clarified. Thus, we decided to characterize the expression of caveolins in bone marrow-derived macrophages (BMDMs) under resting and inflammatory conditions. The effect of classical activators (lipopolysaccharide, LPS; interferon-gamma, IFN-γ) was further potentiated with hypoxic (5% O2) conditions. The activation of p44/42-extracellular signal-regulated kinases 1 and 2 (ERK1/2) and expression of caveolin-1, -2, and -3, hypoxia inducible factor-1 alpha (HIF-1α), as well as inducible nitric oxide synthase (iNOS) was monitored using the Western blot technique. The production of nitric oxide (NO) and tumor necrosis factor-alpha (TNFα) was analyzed by Griess method or ELISA, respectively. BMDMs were also transfected with siRNA against caveolin-2. Importantly, our study showed for the first time that BMDMs expressed only caveolin-2, and its level decreased after activation of macrophages with LPS, IFN-γ, and/or hypoxia. The expression of caveolin-2 negatively correlates with the iNOS and HIF-1α protein levels, as well as with the LPS/IFN-γ- and hypoxia-induced activation of ERK1/2. We concluded that caveolin-2 is most probably involved in regulation of pro-inflammatory responses of BMDMs, triggered via activation of ERK1/2. PMID:26215374

  13. Acrolein activates matrix metalloproteinases by increasing reactive oxygen species in macrophages

    SciTech Connect

    O'Toole, Timothy E. Zheng Yuting; Hellmann, Jason; Conklin, Daniel J.; Barski, Oleg; Bhatnagar, Aruni

    2009-04-15

    Acrolein is a ubiquitous component of environmental pollutants such as automobile exhaust, cigarette, wood, and coal smoke. It is also a natural constituent of several foods and is generated endogenously during inflammation or oxidation of unsaturated lipids. Because increased inflammation and episodic exposure to acrolein-rich pollutants such as traffic emissions or cigarette smoke have been linked to acute myocardial infarction, we examined the effects of acrolein on matrix metalloproteinases (MMPs), which destabilize atherosclerotic plaques. Our studies show that exposure to acrolein resulted in the secretion of MMP-9 from differentiated THP-1 macrophages. Acrolein-treatment of macrophages also led to an increase in reactive oxygen species (ROS), free intracellular calcium ([Ca{sup 2+}]{sub i}), and xanthine oxidase (XO) activity. ROS production was prevented by allopurinol, but not by rotenone or apocynin and by buffering changes in [Ca{sup 2+}]{sub I} with BAPTA-AM. The increase in MMP production was abolished by pre-treatment with the antioxidants Tiron and N-acetyl cysteine (NAC) or with the xanthine oxidase inhibitors allopurinol or oxypurinol. Finally, MMP activity was significantly stimulated in aortic sections from apoE-null mice containing advanced atherosclerotic lesions after exposure to acrolein ex vivo. These observations suggest that acrolein exposure results in MMP secretion from macrophages via a mechanism that involves an increase in [Ca{sup 2+}]{sub I}, leading to xanthine oxidase activation and an increase in ROS production. ROS-dependent activation of MMPs by acrolein could destabilize atherosclerotic lesions during brief episodes of inflammation or pollutant exposure.

  14. EPR demonstration of iron-nitrosyl complex formation by cytotoxic activated macrophages

    SciTech Connect

    Lancaster, J.R. Jr.; Hibbs, J.B. Jr. )

    1990-02-01

    Activated macrophage cytotoxicity is characterized by loss of intracellular iron and inhibition of certain enzymes that have catalytically active nonheme-iron coordinated to sulfur. This phenomenon involves the oxidation of one of the terminal guanidino nitrogen atoms of L-arginine, which results in the production of citrulline and inorganic nitrogen oxides (NO2-, NO3-, and NO). We report here the results of an electron paramagnetic resonance spectroscopic study performed on cytotoxic activated macrophage (CAM) effector cells, which develop the same pattern of metabolic inhibition as their targets. Examination of activated macrophages from mice infected with Mycobacterium bovis (strain bacillus Calmette-Guerin) that were cultured in medium with lipopolysaccharide and L-arginine showed the presence of an axial signal at g = 2.039, which is similar to previously described iron-nitrosyl complexes formed from the destruction of iron-sulfur centers by nitric oxide (NO). Inhibition of the L-arginine-dependent pathway by addition of NG-monomethyl-L-arginine (methyl group on a terminal guanidino nitrogen) inhibits the production of nitrite, nitrate, citrulline, and the g = 2.039 signal. Comparison of the hyperfine structure of the signal from cells treated with L-arginine with terminal guanidino nitrogen atoms of natural abundance N14 atoms or labeled with N15 atoms showed that the nitrosyl group in this paramagnetic species arises from one of these two atoms. These results show that loss of iron-containing enzyme function in CAM is a result of the formation of iron-nitrosyl complexes induced by the synthesis of nitric oxide from the oxidation of a terminal guanidino nitrogen atom of L-arginine.

  15. Quercus infectoria galls possess antioxidant activity and abrogates oxidative stress-induced functional alterations in murine macrophages.

    PubMed

    Kaur, Gurpreet; Athar, Mohammad; Alam, M Sarwar

    2008-02-15

    The present study reports the antioxidant activity of ethanolic extract of Quercus infectoria galls. The antioxidant potency of galls was investigated employing several established in vitro model systems. Their protective efficacy on oxidative modulation of murine macrophages was also explored. Gall extract was found to contain a large amount of polyphenols and possess a potent reducing power. HPTLC analysis of the extract suggested it to contain 19.925% tannic acid (TA) and 8.75% gallic acid (GA). The extract potently scavenged free radicals including DPPH (IC(50)~0.5 microg/ml), ABTS (IC(50)~1 microg/ml), hydrogen peroxide (H(2)O(2)) (IC(50)~2.6 microg/ml) and hydroxyl (*OH) radicals (IC(50)~6 microg/ml). Gall extract also chelated metal ions and inhibited Fe(3+) -ascorbate-induced oxidation of protein and peroxidation of lipids. Exposure of rat peritoneal macrophages to tertiary butyl hydroperoxide (tBOOH) induced oxidative stress in them and altered their phagocytic functions. These macrophages showed elevated secretion of lysosomal hydrolases, and attenuated phagocytosis and respiratory burst. Activity of macrophage mannose receptor (MR) also diminished following oxidant exposure. Pretreatment of macrophages with gall extract preserved antioxidant armory near to control values and significantly protected against all the investigated functional mutilations. MTT assay revealed gall extract to enhance percent survival of tBOOH exposed macrophages. These results indicate that Q. infectoria galls possess potent antioxidant activity, when tested both in chemical as well as biological models. PMID:18076871

  16. Oxidized Low-Density Lipoprotein Contributes to Atherogenesis via Co-activation of Macrophages and Mast Cells

    PubMed Central

    Chen, Chong; Khismatullin, Damir B.

    2015-01-01

    Oxidized low-density lipoprotein (OxLDL) is a risk factor for atherosclerosis, due to its role in endothelial dysfunction and foam cell formation. Tissue-resident cells such as macrophages and mast cells release inflammatory mediators upon activation that in turn cause endothelial activation and monocyte adhesion. Two of these mediators are tumor necrosis factor (TNF)-α, produced by macrophages, and histamine, produced by mast cells. Static and microfluidic flow experiments were conducted to determine the number of adherent monocytes on vascular endothelium activated by supernatants of oxLDL-treated macrophages and mast cells or directly by oxLDL. The expression of adhesion molecules on activated endothelial cells and the concentration of TNF-α and histamine in the supernatants were measured by flow cytometry and enzyme-linked immunosorbent assay, respectively. A low dose of oxLDL (8 μg/ml), below the threshold for the clinical presentation of coronary artery disease, was sufficient to activate both macrophages and mast cells and synergistically increase monocyte-endothelium adhesion via released TNF-α and histamine. The direct exposure of endothelial cells to a much higher dose of oxLDL (80 μg/ml) had less effect on monocyte adhesion than the indirect activation via oxLDL-treated macrophages and mast cells. The results of this work indicate that the co-activation of macrophages and mast cells by oxLDL is an important mechanism for the endothelial dysfunction and atherogenesis. The observed synergistic effect suggests that both macrophages and mast cells play a significant role in early stages of atherosclerosis. Allergic patients with a lipid-rich diet may be at high risk for cardiovascular events due to high concentration of low-density lipoprotein and histamine in arterial vessel walls. PMID:25811595

  17. CX3CR1 deficiency suppresses activation and neurotoxicity of microglia/macrophage in experimental ischemic stroke

    PubMed Central

    2014-01-01

    Background Chemokine (C-X3-C motif) ligand 1 (CX3CL1)/ CX3C chemokine receptor 1 (CX3CR1) signaling is important in modulating the communication between neurons and resident microglia/migrated macrophages in the central nervous system (CNS). Although CX3CR1 deficiency is associated with an improved outcome following ischemic brain injury, the mechanism of this observation is largely unknown. The aim of this study was to investigate how CX3CR1 deficiency influences microglia/macrophage functions in the context of its protection following brain ischemia. Methods Wild-type (WT) and CX3CR1-deficient (CX3CR1-/-) mice were subjected to transient middle cerebral artery occlusion (MCAO) and reperfusion. The ischemic brain damage was monitored by rodent high-field magnetic resonance imaging. Neurological deficit was assessed daily. Neuronal apoptotic death and reactive oxygen species (ROS) production were analyzed by immunostaining and live imaging. Activation/inflammatory response of microglia/macrophage were assessed using immunohistochemistry, flow cytometry, 5-bromo-2-deoxyuridine labeling, cytokine ELISA, and real-time PCR. Results CX3CR1-/- mice displayed significantly smaller infarcts and less severe neurological deficits compared to WT controls, following MCAO. In addition, CX3CR1-/- MCAO mice displayed fewer apoptotic neurons and reduced ROS levels. Impaired CX3CR1 signaling abrogated the recruitment of monocyte-derived macrophages from the periphery, suppressed the proliferation of CNS microglia and infiltrated macrophage, facilitated the alternative activation (M2 state) of microglia/macrophages, and attenuated their ability to synthesize and release inflammatory cytokines. Conclusion Our results suggest that inhibition of CX3CR1 signaling could function as a therapeutic modality in ischemic brain injury, by reducing recruitment of peripheral macrophages and expansion/activation of CNS microglia and macrophages, resulting in protection of neurological function

  18. Enhanced superoxide anion production in activated peritoneal macrophages from English sole (Pleuronectes vetulus) exposed to PACs

    SciTech Connect

    Clemons, E.; Arkoosh, M.; Casillas, E.

    1995-12-31

    In fish, as in mammals, macrophages play a vital role in the destruction of infective organisms. The purpose of this study was to determine if peritoneal macrophages (M{O}s) from English sole (Pleuronectes vetulus), a marine benthic fish, have an altered ability to produce cytotoxic reactive oxygen intermediates (ROIs) after exposure to polycyclic aromatic compounds (PACs). ROIs are the principle product of M{O}s used to destroy engulfed organisms. Assay conditions, including the concentration of M{O}s, type of in vitro stimulant, tissue culture media, and incubation time were optimized to measure the production of superoxide anion (O{sub 2}{minus}), the progenitor ROI, in English sole M{O}s. English sole were injected with an organic solvent extract of a PAH-contaminated sediment, equivalent to 20g sediment/kg fish, via their dorsal lymphatic sinus, and peritoneal M{O}s were harvested on days 1, 3, 5, 7, and 14 post injection. Activated peritoneal M{O}s from English sole injected with the sediment extract produced significantly more superoxide radicals after stimulation in vitro with either opsonized zymosan (OZ) or phorbol myristate acetate (PMA) than the vehicle injected or control fish. Specifically, activated peritoneal M{O}s stimulated with PMA in vitro produced greater amounts (compared to controls) of O{sub 2}{minus} on days 7 and 14 after exposure, whereas the same cells stimulated with OZ showed heightened production only on day 7 after exposure. No differences in the basal amounts of O{sub 2}{minus} production from activated peritoneal M{O}s between the treatment groups were observed. This study shows that exposure of English sole to PACs altered production of O{sub 2}{minus} by macrophages, however, the consequence to the immunocompetence of exposed fish remains to be elucidated.

  19. CpGB DNA activates dermal macrophages and specifically recruits inflammatory monocytes into the skin.

    PubMed

    Mathes, Allison L; Rice, Lisa; Affandi, Alsya J; DiMarzio, Michael; Rifkin, Ian R; Stifano, Giuseppina; Christmann, Romy B; Lafyatis, Robert

    2015-02-01

    Toll-like receptor 9 (TLR9) drives innate immune responses after recognition of foreign or endogenous DNA containing unmethylated CpG motifs. DNA-mediated TLR9 activation is highly implicated in the pathogenesis of several autoimmune skin diseases, yet its contribution to the inflammation seen in these diseases remains unclear. In this study, TLR9 ligand, CpGB DNA, was administered to mice via a subcutaneous osmotic pump with treatment lasting 1 or 4 weeks. Gene expression and immunofluorescence analyses were used to determine chemokine expression and cell recruitment in the skin surrounding the pump outlet. CpGB DNA skin treatment dramatically induced a marked influx of CD11b+ F4/80+ macrophages, increasing over 4 weeks of treatment, and induction of IFNγ and TNFα expression. Chemokines, CCL2, CCL4, CCL5, CXCL9 and CXCL10, were highly induced in CpGB DNA-treated skin, although abrogation of these signalling pathways individually did not alter macrophage accumulation. Flow cytometry analysis showed that TLR9 activation in the skin increased circulating CD11b+ CD115+ Ly6C(hi) inflammatory monocytes following 1 week of CpGB DNA treatment. Additionally, skin-resident CD11b+ cells were found to initially take up subcutaneous CpGB DNA and propagate the subsequent immune response. Using diphtheria toxin-induced monocyte depletion mouse model, gene expression analysis demonstrated that CD11b+ cells are responsible for the CpGB DNA-induced cytokine and chemokine response. Overall, these data demonstrate that chronic TLR9 activation induces a specific inflammatory response, ultimately leading to a striking and selective accumulation of macrophages in the skin. PMID:25425469

  20. Macrophage phenotypes in atherosclerosis.

    PubMed

    Colin, Sophie; Chinetti-Gbaguidi, Giulia; Staels, Bart

    2014-11-01

    Initiation and progression of atherosclerosis depend on local inflammation and accumulation of lipids in the vascular wall. Although many cells are involved in the development and progression of atherosclerosis, macrophages are fundamental contributors. For nearly a decade, the phenotypic heterogeneity and plasticity of macrophages has been studied. In atherosclerotic lesions, macrophages are submitted to a large variety of micro-environmental signals, such as oxidized lipids and cytokines, which influence the phenotypic polarization and activation of macrophages resulting in a dynamic plasticity. The macrophage phenotype spectrum is characterized, at the extremes, by the classical M1 macrophages induced by T-helper 1 (Th-1) cytokines and by the alternative M2 macrophages induced by Th-2 cytokines. M2 macrophages can be further classified into M2a, M2b, M2c, and M2d subtypes. More recently, additional plaque-specific macrophage phenotypes have been identified, termed as Mox, Mhem, and M4. Understanding the mechanisms and functional consequences of the phenotypic heterogeneity of macrophages will contribute to determine their potential role in lesion development and plaque stability. Furthermore, research on macrophage plasticity could lead to novel therapeutic approaches to counteract cardiovascular diseases such as atherosclerosis. The present review summarizes our current knowledge on macrophage subsets in atherosclerotic plaques and mechanism behind the modulation of the macrophage phenotype. PMID:25319333

  1. Mediation of macrophage cytolytic and phagocytic activities by antibodies of different classes and class-specific Fc-receptors.

    PubMed

    Walker, W S

    1977-08-01

    The classes of antibodies that mediate the phagocytosis and cytolysis of 51Cr-labeled chicken erythrocytes by IC-21 macrophages, an established line of mouse peritoneal macrophages, were identified. The phagocytic activity of IC-21 macrophages, as determined by a functional inhibition assay with mouse myeloma proteins, depended mainly on IgM and IgG2a antibodies and to a lesser extent on IgG2b antibodies. Extracellular cytolysis of target cells was mediated solely by IgG2b antibodies. These results correlate with the previously documented specificities of discrete Fc-receptors for IgG2a and IgG2b immunoglobulins on IC-21 cells. Thus, phagocytosis and cytolysis appear to be mediated by antibodies of different classes operating through separate and distinct sites on the surface of IC-21 macrophages. PMID:886183

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

    SciTech Connect

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

    1990-01-15

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

  3. Akt-mTORC1 signaling regulates Acly to integrate metabolic input to control of macrophage activation

    PubMed Central

    Covarrubias, Anthony J; Aksoylar, Halil Ibrahim; Yu, Jiujiu; Snyder, Nathaniel W; Worth, Andrew J; Iyer, Shankar S; Wang, Jiawei; Ben-Sahra, Issam; Byles, Vanessa; Polynne-Stapornkul, Tiffany; Espinosa, Erika C; Lamming, Dudley; Manning, Brendan D; Zhang, Yijing; Blair, Ian A; Horng, Tiffany

    2016-01-01

    Macrophage activation/polarization to distinct functional states is critically supported by metabolic shifts. How polarizing signals coordinate metabolic and functional reprogramming, and the potential implications for control of macrophage activation, remains poorly understood. Here we show that IL-4 signaling co-opts the Akt-mTORC1 pathway to regulate Acly, a key enzyme in Ac-CoA synthesis, leading to increased histone acetylation and M2 gene induction. Only a subset of M2 genes is controlled in this way, including those regulating cellular proliferation and chemokine production. Moreover, metabolic signals impinge on the Akt-mTORC1 axis for such control of M2 activation. We propose that Akt-mTORC1 signaling calibrates metabolic state to energetically demanding aspects of M2 activation, which may define a new role for metabolism in supporting macrophage activation. DOI: http://dx.doi.org/10.7554/eLife.11612.001 PMID:26894960

  4. The FGL2/fibroleukin prothrombinase is involved in alveolar macrophage activation in COPD through the MAPK pathway

    SciTech Connect

    Liu, Yanling; Xu, Sanpeng; Xiao, Fei; Xiong, Yan; Wang, Xiaojin; Gao, Sui; Yan, Weiming; Ning, Qin

    2010-05-28

    Fibrinogen-like protein 2 (FGL2)/fibroleukin has been reported to play a vital role in the pathogenesis of some critical inflammatory diseases by possessing immunomodulatory activity through the mediation of 'immune coagulation' and the regulation of maturation and proliferation of immune cells. We observed upregulated FGL2 expression in alveolar macrophages from peripheral lungs of chronic obstructive pulmonary disease (COPD) patients and found a correlation between FGL2 expression and increased macrophage activation markers (CD11b and CD14). The role of FGL2 in the activation of macrophages was confirmed by the detection of significantly decreased macrophage activation marker (CD11b, CD11c, and CD71) expression as well as the inhibition of cell migration and inflammatory cytokine (IL-8 and MMP-9) production in an LPS-induced FGL2 knockdown human monocytic leukemia cell line (THP-1). Increased FGL2 expression co-localized with upregulated phosphorylated p38 mitogen-activated protein kinase (p38-MAPK) in the lung tissues from COPD patients. Moreover, FGL2 knockdown in THP-1 cells significantly downregulated LPS-induced phosphorylation of p38-MAPK while upregulating phosphorylation of c-Jun N-terminal kinase (JNK). Thus, we demonstrate that FGL2 plays an important role in macrophage activation in the lungs of COPD patients through MAPK pathway modulation.

  5. Immunosuppression associated with the development of chronic infections with Rickettsia tsutsugamushi: adherent suppressor cell activity and macrophage activation.

    PubMed Central

    Jerrells, T R

    1985-01-01

    Measures of general immunocompetency such as lymphocyte responses to mitogens and alloantigens and the ability to produce antibody to T-dependent and T-independent antigens were evaluated during the development of chronic infections with Rickettsia tsutsugamushi resulting from subcutaneous infection of BALB/c mice. It was found that a transient immunosuppression was demonstrable regardless of the infecting strain of rickettsiae; however, the immunosuppression produced by the Karp and Kato strains was more pronounced and longer lived. As a marked splenomegaly resulting from inflammatory macrophage influx accompanied this immunosuppression, mitogen- and antigen-induced lymphocyte proliferation was also evaluated after adherent cell depletion or in the presence of indomethacin, and both treatments significantly improved the responses. Isolated splenic macrophages were shown to suppress the responses of lymphocytes from naive mice as well as to exhibit parameters of activation including tumor cell cytolysis and cytostasis and the ability to inhibit the replication of R. tsutsugamushi in vitro. These data suggest an association between macrophage activation involved in rickettsial clearance and a transient immunosuppression. PMID:2931378

  6. CX3CL1-mediated macrophage activation contributed to paclitaxel-induced DRG neuronal apoptosis and painful peripheral neuropathy.

    PubMed

    Huang, Zhen-Zhen; Li, Dai; Liu, Cui-Cui; Cui, Yu; Zhu, He-Quan; Zhang, Wen-Wen; Li, Yong-Yong; Xin, Wen-Jun

    2014-08-01

    Painful peripheral neuropathy is a dose-limiting side effect of paclitaxel therapy, which hampers the optimal clinical management of chemotherapy in cancer patients. Currently the underlying mechanisms remain largely unknown. Here we showed that the clinically relevant dose of paclitaxel (3×8mg/kg, cumulative dose 24mg/kg) induced significant upregulation of the chemokine CX3CL1 in the A-fiber primary sensory neurons in vivo and in vitro and infiltration of macrophages into the dorsal root ganglion (DRG) in rats. Paclitaxel treatment also increased cleaved caspase-3 expression, induced the loss of primary afferent terminal fibers and decreased sciatic-evoked A-fiber responses in the spinal dorsal horn, indicating DRG neuronal apoptosis induced by paclitaxel. In addition, the paclitaxel-induced DRG neuronal apoptosis occurred exclusively in the presence of macrophage in vitro study. Intrathecal or systemic injection of CX3CL1 neutralizing antibody blocked paclitaxel-induced macrophage recruitment and neuronal apoptosis in the DRG, and also attenuated paclitaxel-induced allodynia. Furthermore, depletion of macrophage by systemic administration of clodronate inhibited paclitaxel-induced allodynia. Blocking CX3CL1 decreased activation of p38 MAPK in the macrophage, and inhibition of p38 MAPK activity blocked the neuronal apoptosis and development of mechanical allodynia induced by paclitaxel. These findings provide novel evidence that CX3CL1-recruited macrophage contributed to paclitaxel-induced DRG neuronal apoptosis and painful peripheral neuropathy. PMID:24681252

  7. Monosodium Urate Activates Src/Pyk2/PI3 Kinase and Cathepsin Dependent Unconventional Protein Secretion From Human Primary Macrophages*

    PubMed Central

    Välimäki, Elina; Miettinen, Juho J.; Lietzén, Niina; Matikainen, Sampsa; Nyman, Tuula A.

    2013-01-01

    Monosodium urate (MSU) is an endogenous danger signal that is crystallized from uric acid released from injured cells. MSU is known to activate inflammatory response in macrophages but the molecular mechanisms involved have remained uncharacterized. Activated macrophages start to secrete proteins to activate immune response and to recruit other immune cells to the site of infection and/or tissue damage. Secretome characterization after activation of innate immune system is essential to unravel the details of early phases of defense responses. Here, we have analyzed the secretome of human primary macrophages stimulated with MSU using quantitative two-dimensional gel electrophoresis based proteomics as well as high-throughput qualitative GeLC-MS/MS approach combining protein separation by SDS-PAGE and protein identification by liquid chromatography-MS/MS. Both methods showed that MSU stimulation induced robust protein secretion from lipopolysaccharide-primed human macrophages. Bioinformatic analysis of the secretome data showed that MSU stimulation strongly activates unconventional, vesicle mediated protein secretion. The unconventionally secreted proteins included pro-inflammatory cytokines like IL-1β and IL-18, interferon-induced proteins, and danger signal proteins. Also active forms of lysosomal proteases cathepsins were secreted on MSU stimulation, and cathepsin activity was essential for MSU-induced unconventional protein secretion. Additionally, proteins associated to phosphorylation events including Src family tyrosine kinases were increased in the secretome of MSU-stimulated cells. Our functional studies demonstrated that Src, Pyk2, and PI3 kinases act upstream of cathepsins to activate the overall protein secretion from macrophages. In conclusion, we provide the first comprehensive characterization of protein secretion pathways activated by MSU in human macrophages, and reveal a novel role for cathepsins and Src, Pyk2, PI3 kinases in the activation of

  8. Post-transcriptional control of NLRP3 inflammasome activation in colonic macrophages

    PubMed Central

    Filardy, Alessandra A.; He, Jianping; Bennink, Jack; Yewdell, Jonathan; Kelsall, Brian L.

    2016-01-01

    Colonic macrophages (cMPs) are important for intestinal homeostasis as they kill microbes yet produce regulatory cytokines. Activity of the NLRP3 inflammasome, a major sensor of stress and microorganisms that results in pro-inflammatory cytokine production and cell death must be tightly controlled in the intestine. We demonstrate that resident cMPs are hyporesponsive to NLRP3 inflammasome activation due to a remarkable level of post-transcriptional control of NLRP3 and proIL-1β protein expression, which was also seen for TNF-α and IL-6, but lost during experimental colitis. Resident cMPs rapidly degraded NLRP3 and proIL-1β proteins by the ubiquitin/proteasome system. Finally, blocking IL-10R-signaling in vivo enhanced NLRP3 and proIL-1β protein, but not mRNA levels in resident cMPs implicating a role for IL-10 in environmental conditioning of cMPs. These data are the first to show dramatic post-transcriptional control of inflammatory cytokine production by a relevant tissue-derived macrophage population and proteasomal degradation of proIL-1β and NLRP3 as a mechanism to control inflammasome activation; findings which have broad implications for our understanding of intestinal and systemic inflammatory diseases. PMID:26627461

  9. Inhibition of Inflammatory Response by Artepillin C in Activated RAW264.7 Macrophages

    PubMed Central

    Czuba, Zenon P.; Król, Wojciech

    2013-01-01

    Artepillin C (3,5-diprenyl-4-hydroxycinnamic acid) is the main bioactive component of Brazilian green propolis. The aim of this study was to investigate the anti-inflammatory effect of artepillin C on LPS + IFN-γ- or PMA-stimulated RAW264.7 macrophages. The cell viability was evaluated by MTT and LDH assays. The radical scavenging ability was determined using DPPH• and ABTS•+. ROS and RNS generation was analyzed by chemiluminescence. NO concentration was detected by the Griess reaction. The release of various cytokines by activated RAW264.7 cells was measured in the culture supernatants using a multiplex bead array system based on xMAP technology. NF-κB activity was confirmed by the ELISA-based TransAM NF-κB kit. At the tested concentrations, the compound did not decrease the cell viability and did not cause the cytotoxicity. Artepillin C exerted strong antioxidant activity, significantly inhibited the production of ROS, RNS, NO, and cytokine IL-1β, IL-3, IL-4, IL-5, IL-9, IL-12p40, IL-13, IL-17, TNF-α, G-CSF, GM-CSF, MCP-1, MIP-1α, MIP-1β, RANTES, and KC, and markedly blocked NF-κB expression in stimulated RAW264.7 macrophages. Our findings provide new insights for understanding the mechanism involved in the anti-inflammatory effect of artepillin C and support the application of Brazilian green propolis in complementary and alternative medicine. PMID:23781267

  10. Regulation of Candida albicans Interaction with Macrophages through the Activation of HOG Pathway by Genistein.

    PubMed

    Cui, Shuna; Hassan, Rabeay Y A; Heintz-Buschart, Anna; Bilitewski, Ursula

    2016-01-01

    The severity of infections caused by Candida albicans, the most common opportunistic human fungal pathogen, needs rapid and effective antifungal treatments. One of the effective ways is to control the virulence factors of the pathogen. Therefore, the current study examined the effects of genistein, a natural isoflavone present in soybeans, on C. albicans. The genistein-treated C. albicans cells were then exposed to macrophages. Although no inhibition effect on the growth rates of C. albicans was noted an enhancement of the immune response to macrophages has been observed, indicated by phagocytosis and release of cytokines TNF-α and IL-10. The effect of genistein on the enhanced phagocytosis can be mimicked by the fungicides fludioxonil or iprodione, which inhibit the histidine kinase Cos1p and lead to activation of HOG pathway. The western blot results showed a clear phosphorylation of Hog1p in the wild type strain of C. albicans after incubation with genistein. In addition, effects of genistein on the phosphorylation of Hog1p in the histidine kinase mutants Δcos1 and Δsln1 were also observed. Our results thus indicate a new bio-activity of genistein on C. albicans by activation of the HOG pathway of the human pathogen C. albicans. PMID:26828477

  11. Nitroxyl (HNO) reduces endothelial and monocyte activation and promotes M2 macrophage polarization.

    PubMed

    Andrews, Karen L; Sampson, Amanda K; Irvine, Jennifer C; Shihata, Waled A; Michell, Danielle L; Lumsden, Natalie G; Lim, Chloe; Huet, Olivier; Drummond, Grant R; Kemp-Harper, Barbara K; Chin-Dusting, Jaye P F

    2016-09-01

    Nitroxyl anion (HNO) donors are currently being assessed for their therapeutic utility in several cardiovascular disorders including heart failure. Here, we examine their effect on factors that precede atherosclerosis including endothelial cell and monocyte activation, leucocyte adhesion to the endothelium and macrophage polarization. Similar to the NO donor glyceryl trinitrate (GTN), the HNO donors Angeli's salt (AS) and isopropylamine NONOate (IPA/NO) decreased leucocyte adhesion to activated human umbilical vein endothelial cells (HUVECs) and mouse isolated aorta. This reduction in adhesion was accompanied by a reduction in intercellular adhesion molecule-1 (ICAM-1) and the cytokines monocyte chemoattractant protein 1 (MCP-1) and interleukin 6 (IL-6) which was inhibitor of nuclear factor κB (NFκB) α (IκBα)- and subsequently NFκB-dependent. Intriguingly, the effects of AS on leucocyte adhesion, like those on vasodilation, were found to not be susceptible to pharmacological tolerance, unlike those observed with GTN. As well, HNO reduces monocyte activation and promotes polarization of M2 macrophages. Taken together, our data demonstrate that HNO donors can reduce factors that are associated with and which precede atherosclerosis and may thus be useful therapeutically. Furthermore, since the effects of the HNO donors were not subject to tolerance, this confers an additional advantage over NO donors. PMID:27231254

  12. Enhanced antitumoral efficacy by intratumoral perfusion of activated macrophages associated with photodynamic therapy

    NASA Astrophysics Data System (ADS)

    Dima, Vasile F.; Vasiliu, Virgil V.; Laky, Dezideriu; Ionescu, Paul; Dima, Stefan V.

    1996-01-01

    Experiments were performed on five batches of Wistar inbred rats with Walker-256 carcinosarcoma receiving photodynamic therapy (PDT), rMuIFN-gamma activated macrophages (AM(Phi) ) or associated therapy (PDT-AM(Phi) -A; PDT-AM(Phi) -B); the control batch (HBSS) consisted of animals with untreated Walker-256 tumors. The results were as follows: the sole treatment (PDT, AM(Phi) ) gave survival rates between 57.2 and 57.7% and cure rates ranging from 23.1 to 34.3%. The 'combined' therapy in multiple doses increased significantly (87.9%) the survival rate of tumor bearing rats as well as the rate of complete tumor regression (72.7%). Cell-mediated immunity test values in batches III and IV exposed to multiple doses of PDT-AM(Phi) showed higher values as compared to the values noticed in batches I - II and the control batch V, performed at 12 and 21 days post-treatment. Summing up, these results demonstrate that 'combined' photodynamic treatment and biotherapy with interferon activated macrophages stimulate cell-mediated antitumoral activity, increase survival rates and reduce incidence of Walker-256 carcinosarcoma in rat model.

  13. Human Macrophage SCN5A Activates an Innate Immune Signaling Pathway for Antiviral Host Defense*

    PubMed Central

    Jones, Alexis; Kainz, Danielle; Khan, Faatima; Lee, Cara; Carrithers, Michael D.

    2014-01-01

    Pattern recognition receptors contain a binding domain for pathogen-associated molecular patterns coupled to a signaling domain that regulates transcription of host immune response genes. Here, a novel mechanism that links pathogen recognition to channel activation and downstream signaling is proposed. We demonstrate that an intracellular sodium channel variant, human macrophage SCN5A, initiates signaling and transcription through a calcium-dependent isoform of adenylate cyclase, ADCY8, and the transcription factor, ATF2. Pharmacological stimulation with a channel agonist or treatment with cytoplasmic poly(I:C), a mimic of viral dsRNA, activates this pathway to regulate expression of SP100-related genes and interferon β. Electrophysiological analysis reveals that the SCN5A variant mediates nonselective outward currents and a small, but detectable, inward current. Intracellular poly(I:C) markedly augments an inward voltage-sensitive sodium current and inhibits the outward nonselective current. These results suggest human macrophage SCN5A initiates signaling in an innate immune pathway relevant to antiviral host defense. It is postulated that SCN5A is a novel pathogen sensor and that this pathway represents a channel activation-dependent mechanism of transcriptional regulation. PMID:25368329

  14. Smoke exposure of human macrophages reduces HDAC3 activity, resulting in enhanced inflammatory cytokine production.

    PubMed

    Winkler, Aaron R; Nocka, Karl N; Williams, Cara M M

    2012-08-01

    Chronic obstructive pulmonary disease (COPD) is a debilitating condition resulting from exposure to pollutants such as cigarette smoke. Pulmonary macrophages secrete a plethora of inflammatory mediators that are increased in the lungs of COPD patients, but whether this phenotype results directly from smoke exposure remains unknown. Using an in vitro model for alveolar macrophages (AM) derived from human peripheral blood monocytes with granulocyte-macrophage stimulating factor (GM-MØ), we analyzed the mechanistic connection between cigarette smoke exposure and histone deacetylase (HDAC) regulation, hypothesized to be a contributing factor in COPD pathophysiology. Here we show that acute smoke exposure inhibits HDAC enzymatic activity in GM-MØ. Analysis of mRNA and total cellular proteins for expression of class I (1, 2, 3 and 8), class II (4, 5, 6, 7, 9, 10), and class IV (11) HDAC revealed no effect of smoke exposure, whereas nuclear HDAC3 protein content was reduced. To better understand the physiological significance of reduced HDAC3 activity, we utilized siRNA to knockdown HDAC1, 2 and 3 individually. Interestingly, siRNA-mediated reduction of HDAC3 resulted in increased production of IL8 and IL1β in response to LPS stimulation, while HDAC2 knockdown had no effect on either cytokine. Lower nuclear content of HDAC3 in the context of equivalent total HDAC protein levels following smoke exposure may reflect increased nuclear export of HDAC3, allowing increased nuclear factor kappa b (NF-κB ) driven cytokine expression that can contribute to inflammation. PMID:22613758

  15. Rapid Temporal Dynamics of Transcription, Protein Synthesis, and Secretion during Macrophage Activation*

    PubMed Central

    Eichelbaum, Katrin; Krijgsveld, Jeroen

    2014-01-01

    Macrophages provide the first line of host defense with their capacity to react to an array of cytokines and bacterial components requiring tight regulation of protein expression and secretion to invoke a properly tuned innate immune response. To capture the dynamics of this system, we introduce a novel method combining pulsed stable isotope labeling with amino acids in cell culture (SILAC) with pulse labeling using the methionine analog azidohomoalanine that allows the enrichment of newly synthesized proteins via click-chemistry followed by their identification and quantification by mass spectrometry. We show that this permits the analysis of proteome changes on a rapid time scale, as evidenced by the detection of 4852 newly synthesized proteins after only a 20-min SILAC pulse. We have applied this methodology to study proteome response during macrophage activation in a time-course manner. We have combined this with full proteome, transcriptome, and secretome analyses, producing an integrative analysis of the first 3 h of lipopolysaccharide-induced macrophage activation. We observed the rapid induction of multiple processes well known to TLR4 signaling, as well as anti-inflammatory proteins and proteins not previously associated with immune response. By correlating transcriptional, translational, and secretory events, we derived novel mechanistic principles of processes specifically induced by lipopolysaccharides, including ectodomain shedding and proteolytic processing of transmembrane and extracellular proteins and protein secretion independent of transcription. In conclusion, we demonstrate that the combination of pulsed azidohomoalanine and pulsed SILAC permits the detailed characterization of proteomic events on a rapid time scale. We anticipate that this approach will be very useful in probing the immediate effects of cellular stimuli and will provide mechanistic insight into cellular perturbation in multiple biological systems. The data have been deposited

  16. Activation of macrophages by an exopolysaccharide isolated from Antarctic Psychrobacter sp. B-3

    NASA Astrophysics Data System (ADS)

    Yu, Leiye; Sun, Guojie; Wei, Jingfang; Wang, Yingze; Du, Chao; Li, Jiang

    2016-09-01

    An exopolysaccharide (EPS) was isolated and purified from an Antarctic psychrophilic bacterium B-3, identified as Psychrobacter sp., and the activation of RAW264.7 cells by B-3 EPS was investigated. The results show that B-3 EPS, over a certain concentration range, promoted cell viability, nitric oxide production, tumor necrosis factor (TNF)α secretion, and phagocytic ability. Furthermore, TAK-242, an inhibitor of the toll-like receptor 4 (TLR4) significantly reduced nitric oxide production by these cells after stimulation with B-3 EPS. Moreover, B-3 EPS induced p65 phosphorylation and IκBα degradation in these cells. In conclusion, B-3 EPS might have activated RAW264.7 cells by combining with TLR4 on cell surface and triggering activation of NF-κB signaling pathways, implying that this EPS could activate macrophages and regulate initial immune response.

  17. Activation of macrophages by an exopolysaccharide isolated from Antarctic Psychrobacter sp. B-3

    NASA Astrophysics Data System (ADS)

    Yu, Leiye; Sun, Guojie; Wei, Jingfang; Wang, Yingze; Du, Chao; Li, Jiang

    2016-01-01

    An exopolysaccharide (EPS) was isolated and purified from an Antarctic psychrophilic bacterium B-3, identified as Psychrobacter sp., and the activation of RAW264.7 cells by B-3 EPS was investigated. The results show that B-3 EPS, over a certain concentration range, promoted cell viability, nitric oxide production, tumor necrosis factor (TNF)α secretion, and phagocytic ability. Furthermore, TAK-242, an inhibitor of the toll-like receptor 4 (TLR4) significantly reduced nitric oxide production by these cells after stimulation with B-3 EPS. Moreover, B-3 EPS induced p65 phosphorylation and IκBα degradation in these cells. In conclusion, B-3 EPS might have activated RAW264.7 cells by combining with TLR4 on cell surface and triggering activation of NF-κB signaling pathways, implying that this EPS could activate macrophages and regulate initial immune response.

  18. Activation of mouse macrophages causes no change in expression and function of phorbol diesters' receptors, but is accompanied by alterations in the activity and kinetic parameters of NADPH oxidase.

    PubMed Central

    Berton, G; Cassatella, M; Cabrini, G; Rossi, F

    1985-01-01

    Mouse peritoneal macrophages activated in vivo by the injection of Corynebacterium parvum release larger amounts of superoxide anion (O2-) than macrophages from control mice when stimulated with phorbol myristate acetate (PMA). The biochemical bases for this enhanced response of activated macrophages have been investigated by studying the expression and function of receptors for the stimulant, and the activity of the enzyme NADPH oxidase which is responsible for the production of O2- in leucocytes. Studies of binding of phorbol dibutyrate, an agent closely related to PMA, showed that the affinity constants (Kds) and the number of binding sites were the same in resident and activated peritoneal macrophages. The activity of the NADPH oxidase was, however, different in the two macrophage populations which differ in their capacity to release O2-. NADPH oxidase activity was studied in macrophage monolayers after lysis with deoxycholate. The main features of this activity were as follows: stimulation of macrophages with PMA or zymosan caused an increase in NADPH-dependent O2- production; NADPH oxidase activity in the lysates followed the same dose-response curve for different concentrations of PMA as O2- release by intact macrophages; O2- release by intact macrophages could be fully accounted for by NADPH-dependent O2- production by macrophage lysates; activity was strictly substrate-specific, in that NADH could not substitute for NADPH; after stimulation with PMA or zymosan, NADPH oxidase activity was higher in lysates of C. parvum-activated macrophages than in lysates of resident macrophages; NADPH oxidase activities of activated and resident macrophages differed markedly in their kinetic parameters. The NADPH oxidase of macrophages activated by C. parvum or trehalose dimycolate of mycobacterial origin displayed a five to seven times lower Km compared to the enzyme in resident macrophages. PMID:2981767

  19. 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. PMID:26453753

  20. Transforming growth factor beta 1 and gamma interferon provide opposing signals to lipopolysaccharide-activated mouse macrophages.

    PubMed Central

    Hausmann, E H; Hao, S Y; Pace, J L; Parmely, M J

    1994-01-01

    Bacterial lipopolysaccharides (LPS) are potent inducers of macrophage activation, leading to the production of a number of proinflammatory mediators. Although several cytokines that prime macrophages for enhanced LPS-triggered responses have been identified, far less is known regarding the role that cytokines play in down-regulating macrophage responses to LPS. This study was designed to determine the effects of recombinant transforming growth factor beta 1 (rTGF-beta 1) on macrophage activation by LPS. Pretreatment of either mouse peritoneal macrophages or cells of the RAW 264.7 macrophage-like cell line with rTGF-beta 1 inhibited their ability to produce both tumor necrosis factor alpha (TNF-alpha) and nitric oxide (NO) in response to LPS. These inhibitory effects were reversed by increasing the concentration of LPS or by priming cells with optimal concentrations of recombinant gamma interferon (rIFN-gamma). Pretreatment of cells with rTGF-beta 1 had only a modest inhibitory effect on the expression of TNF-alpha mRNA. By contrast, the expression of mRNA for the inducible form of nitric oxide synthase (iNOS), which is responsible for NO production in activated macrophages, was significantly inhibited by rTGF-beta 1 pretreatment. Thus, rTGF-beta 1-dependent suppression of macrophage TNF-alpha biosynthesis was manifest at a posttranscriptional level, whereas the inhibition of NO production correlated with a direct effect on iNOS gene expression. Importantly, both of these suppressive effects of rTGF-beta 1 were reversed by exposing the cells to priming concentrations of rIFN-gamma. As with NO production, immunocytochemical analysis of iNOS expression in LPS-stimulated macrophages revealed that rIFN-gamma and rTGF-beta 1 had antagonistic effects, with the former increasing, and the latter reducing, the number of iNOS-expressing cells induced by LPS. These data suggest that a balance between the priming effects of IFN-gamma and the inhibitory effects of TGF-beta 1 can

  1. Docosahexaenoic acid consumption inhibits deoxynivalenol-induced CREB/ATF1 activation and IL-6 gene transcription in mouse macrophages.

    PubMed

    Jia, Qunshan; Zhou, Hui-Ren; Shi, Yuhui; Pestka, James J

    2006-02-01

    The mycotoxin deoxynivalenol (DON) induces IgA nephropathy in mice by upregulating IL-6 expression, which is suppressed by (n-3) PUFA consumption. The purpose of this study was to test the hypothesis that consumption of the (n-3) PUFA docosahexaenoic acid (DHA) interferes with DON-induced transcriptional and post-transcriptional upregulation of IL-6 mRNA in murine macrophages. DON evoked expression of IL-6 mRNA and IL-6 heterogenous nuclear RNA (hnRNA), an indicator of ongoing IL-6 transcription, in macrophages elicited from mice fed control AIN-93G diet for 4 wk, whereas expression of both RNA species was suppressed in macrophages from mice fed AIN-93G modified to contain 30 g DHA/kg diet for the same time period. DON enhanced IL-6 mRNA stability similarly in macrophages from control and DHA-fed mice suggesting that (n-3) PUFA effects were not post-transcriptional. DON upregulated binding activity of cAMP response element binding protein (CREB) and activator protein (AP-1) to their respective consensus sequences in nuclear extracts from control-fed mice, whereas both activities were suppressed in nuclear extracts from DHA-fed mice. DON induced phosphorylation of CREB at Ser-133 and ATF1 at Ser-63 as well as intranuclear binding of phospho-CREB/ATF1 to the cis element of the IL-6 promoter in control macrophages, whereas both activities were inhibited in macrophages from DHA-fed mice. DHA consumption blocked DON-induced phosphorylation of the CREB kinase AKT. Inhibition of AKT suppressed both CREB/ATF1 phosphorylation and IL-6 transcription. These data suggest that DHA consumption suppresses DON-induced IL-6 transcription in macrophages in part by interfering with AKT-dependent phosphorylation and subsequent binding of CREB/ATF1 to the IL-6 promoter. PMID:16424113

  2. 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. PMID:26093918

  3. Early Macrophage Recruitment and Alternative Activation Are Critical for the Later Development of Hypoxia-induced Pulmonary Hypertension

    PubMed Central

    Vergadi, Eleni; Chang, Mun Seog; Lee, Changjin; Liang, Olin; Liu, Xianlan; Fernandez-Gonzalez, Angeles; Mitsialis, S. Alex; Kourembanas, Stella

    2011-01-01

    Background Lung inflammation precedes the development of hypoxia-induced pulmonary hypertension (HPH); however its role in the pathogenesis of HPH is poorly understood. We sought to characterize the hypoxic inflammatory response and elucidate its role in the development of HPH. We also aimed to investigate the mechanisms by which heme oxygenase-1 (HO-1), an anti-inflammatory enzyme, is protective in HPH. Methods and Results We generated bitransgenic mice that overexpress human HO-1 under doxycycline (dox) control in an inducible, lung-specific manner. Hypoxic exposure of mice in the absence of dox resulted in early transient accumulation of monocytes/macrophages in the bronchoalveolar lavage. Alveolar macrophages acquired an alternatively activated phenotype (M2) in response to hypoxia, characterized by the expression of Found in Inflammatory Zone-1, Arginase-1 and Chitinase-3-like-3. A brief, two-day pulse of dox delayed but did not prevent the peak of hypoxic inflammation, and could not protect from HPH. In contrast, a seven-day dox treatment sustained high HO-1 levels during the entire period of hypoxic inflammation, inhibited macrophage accumulation and activation, induced macrophage IL-10 expression, and prevented the development of HPH. Supernatants from hypoxic M2 macrophages promoted proliferation of pulmonary artery smooth muscle cells while treatment with carbon monoxide, a HO-1 enzymatic product, abrogated this effect. Conclusions Early recruitment and alternative activation of macrophages in hypoxic lungs is critical for the later development of HPH. HO-1 may confer protection from HPH by effectively modifing macrophage activation state in hypoxia. PMID:21518986

  4. Macrophage activation syndrome as the initial manifestation of severe juvenile onset systemic lupus erythematosus. Favorable response to cyclophosphamide.

    PubMed

    Torres Jiménez, Alfonso; Solís Vallejo, Eunice; Zeferino Cruz, Maritza; Céspedes Cruz, Adriana; Sánchez Jara, Berenice

    2014-01-01

    The macrophage activation syndrome is a rare but potentially fatal complication of patients with autoimmune rheumatic diseases. This is a clinicopathological entity characterized by activation of histiocytes with prominent hemophagocytosis in the bone marrow and other reticuloendothelial systems. In patients with lupus it may mimic an exacerbation of the disease or infection. We report the case of a 7-year-old girl in whom the diagnosis of lupus erythematosus and macrophage activation syndrome was simultaneously made with response to the use of cyclophosphamide. PMID:24035795

  5. Cardiac Tissue Injury and Remodeling Is Dependent Upon MR Regulation of Activation Pathways in Cardiac Tissue Macrophages.

    PubMed

    Shen, Jimmy Z; Morgan, James; Tesch, Greg H; Rickard, Amanda J; Chrissobolis, Sophocles; Drummond, Grant R; Fuller, Peter J; Young, Morag J

    2016-08-01

    Macrophage mineralocorticoid receptor (MR) signaling is an important mediator of cardiac tissue inflammation and fibrosis. The goal of the present study was to determine the cellular mechanisms of MR signaling in macrophages that promote cardiac tissue injury and remodeling. We sought to identify specific markers of MR signaling in isolated tissue macrophages (cardiac, aortic) vs splenic mononuclear cells from wild-type and myeloid MR-null mice given vehicle/salt or deoxycorticosterone (DOC)/salt for 8 weeks. Cardiac tissue fibrosis in response to 8 weeks of DOC/salt treatment was found in the hearts from wild-type but not myeloid MR-null mice. This was associated with an increased expression of the profibrotic markers TGF-β1 and matrix metalloproteinase-12 and type 1 inflammatory markers TNFα and chemokine (C-X-C motif) ligand-9 in cardiac macrophages. Differential expression of immunomodulatory M2-like markers (eg, arginase-1, macrophage scavenger receptor 1) was dependent on the tissue location of wild-type and MR-null macrophages. Finally, intact MR signaling is required for the phosphorylation of c-Jun NH2-terminal kinase in response to a proinflammatory stimulus in bone marrow monocytes/macrophages in culture. These data suggest that the activation of the c-Jun NH2-terminal kinase pathway in macrophages after a tissue injury and inflammatory stimuli in the DOC/salt model is MR dependent and regulates the transcription of downstream profibrotic factors, which may represent potential therapeutic targets in heart failure patients. PMID:27253999

  6. Macrophages activation by heparanase is mediated by TLR-2 and TLR-4 and associates with plaque progression

    PubMed Central

    Blich, Miry; Golan, Amnon; Arvatz, Gil; Sebbag, Anat; Shafat, Itay; Sabo, Edmond; Cohen-Kaplan, Victoria; Petcherski, Sirouch; Avniel-Polak, Shani; Eitan, Amnon; Hammerman, Haim; Aronson, Doron; Axelman, Elena; Ilan, Neta; Nussbaum, Gabriel; Vlodavsky, Israel

    2012-01-01

    Objective Factors and mechanisms that activate macrophages in atherosclerotic plaques are incompletely understood. We examined the capacity of heparanase to activate macrophages. Results/Methods Highly purified heparanase was added to mouse peritoneal macrophages (MPM) and macrophage-like J774 cells and the levels of TNFα, MMP-9, IL-1, and MCP-1 were evaluated by ELISA. Gene expression was determined by RT-PCR. Cells collected from Toll like receptor (TLR)-2 and -4 knockout mice (KO) were evaluated similarly. Heparanase levels in the plasma of patients with acute myocardial infarction (MI), stable angina (SA), and healthy subjects were determined by ELISA. Immunohistochemistry was applied to detect the expression of heparanase in control specimens and specimens of patients with SA or acute MI. Addition or over expression of heparanase variants resulted in marked increase in TNFα, MMP-9, IL-1 and MCP-1 levels. MPM harvested from TLR-2 or TLR-4 knockout mice were not activated by heparanase. Plasma heparanase level was higher in patients with acute MI, compared to patients with SA and healthy subjects. Pathologic coronary specimens obtained from vulnerable plaques showed increased heparanase staining compared to specimens of stable plaque and controls. Conclusion Heparanase activates macrophages, resulting in marked induction of cytokine expression associated with plaque progression towards vulnerability. PMID:23162016

  7. Effects of pristane alone or combined with chloroquine on macrophage activation, oxidative stress, and TH1/TH2 skewness.

    PubMed

    Ouyang, Qiufang; Huang, Ziyang; Wang, Zhenhua; Chen, Xiaoqing; Ni, Jingqin; Lin, Ling

    2014-01-01

    We investigated the protective role of chloroquine against pristane-induced macrophage activation, oxidative stress, and Th1/Th2 skewness in C57BL/6J mice. Those mice were treated with pristane alone or combined with chloroquine. Hematological and biochemical parameters, macrophage phagocytic function, the oxidant/antioxidant index, cytokine for IFN-γ, TNF-α, IL-4, and IL-6, and the isotypes of IgG2a and IgG1 were determined. And the expression of T-bet/GATA-3 and IL-12/IL-10 mRNA in spleen were analyzed by real-time PCR. We found that pristane treatment for a period of 12 or 24 weeks triggered macrophage activation syndrome, characterized by hemophagocytosis in spleen and peripheral blood, enhanced lipid phagocytosis by peritoneal macrophages in vitro, erythropenia and leucopenia, increased anti-Smith, lactic dehydrogenase, triglyceride, and ferritin, as well as hypercytokinemia of IFN-γ, TNF-α, IL-4, and IL-6. In parallel, a significant increase in lipid peroxidation and a decrease in superoxide dismutase, glutathione, and catalase activity, as well as a skewed Th1/Th2 balance in spleen, were observed. However, chloroquine supplementation showed a remarkable amelioration of these abnormalities. Our data indicate that pristane administration induces macrophage activation, oxidative stress, and Th1/Th2 skewness, which can be attenuated by chloroquine. PMID:25136646

  8. Is Synovial Macrophage Activation the Inflammatory Link Between Obesity and Osteoarthritis?

    PubMed

    Sun, Antonia RuJia; Friis, Thor; Sekar, Sunderajhan; Crawford, Ross; Xiao, Yin; Prasadam, Indira

    2016-09-01

    Osteoarthritis (OA) is the most common musculoskeletal disease, affecting nearly 25 % of the world population (WHO reports), leading to pain and disability. There are as yet no clinically proven therapies to halt OA onset or progression; the development of such therapies is, therefore, a national as well as international research priority. Obesity-related metabolic syndrome has been identified as the most significant, but also an entirely preventable risk factor for OA; however, the mechanisms underlying this link remain unclear. We have examined the available literature linking OA and metabolic syndrome. The two conditions have a shared pathogenesis in which chronic low-grade inflammation of affected tissues is recognized as a major factor that is associated with systemic inflammation. In addition, the occurrence of metabolic syndrome appears to alter systemic and local pro-inflammatory cytokines that are also related to the development of OA-like pathologies. Recent findings highlight the importance not only of the elevated number of macrophage in inflamed synovium but also the activation and amplification of the inflammatory state and other pathological changes. The role of local inflammation on the synovium is now considered to be a pharmacological target against which to aim disease-modifying drugs. In this review, we evaluate evidence linking OA, synovitis and metabolic syndrome and discuss the merits of targeting macrophage activation as a valid treatment option for OA. PMID:27422277

  9. Macrophage activation syndrome in a patient with systemic onset of the juvenile idiopathic arthritis

    PubMed Central

    Aggarwal, Hari K.; Rao, Avinash; Mittal, Anshul; Jain, Promil

    2016-01-01

    Systemic onset juvenile idiopathic arthritis (sJIA) is defined as arthritis affecting one or more joint usually in the juvenile age group (< 16 years of age) with or preceded by fever of at least 2 weeks duration that is documented to be daily (“quotidian”) for at least 3 days which may be associated with evanescent (non-fixed) erythematous rash or generalized lymph node enlargement or hepatomegaly/splenomegaly/both or serositis. Macrophage activation syndrome (MAS) is a life-threatening complication of sJIA marked by sudden onset of non-remitting high fever, profound depression in all three blood cell lines (i.e. leukopenia, anemia, and thrombocytopenia), hepatosplenomegaly, lymphadenopathy, and elevated serum liver enzyme levels. In children with systemic juvenile idiopathic arthritis, the clinical picture may mimic sepsis or an exacerbation of the underlying disease. We report a case of a 16-year-old female patient presenting with high grade fever with joint pains and generalized weakness which proved to be systemic onset juvenile idiopathic arthritis with macrophage activation syndrome after ruling out all other differential diagnoses and responded well to intravenous steroids. PMID:27407277

  10. Molecular Network Analysis of Endometriosis Reveals a Novel Role for c-Jun Regulated Macrophage Activation

    PubMed Central

    Beste, Michael T.; Pfäffle-Doyle, Nicole; Prentice, Emily A.; Morris, Stephanie N.; Lauffenburger, Douglas A.; Isaacson, Keith B.; Griffith, Linda G.

    2014-01-01

    Clinical management of endometriosis is limited by the complex relationship between symptom severity, heterogeneous surgical presentations, and variability in clinical outcomes. As a complement to visual classification schemes, molecular profiles of disease activity may improve risk stratification to better inform treatment decisions and identify novel approaches to targeted treatment. Here, we employ a network analysis of information flow within and between inflammatory cells to discern consensus behaviors characterizing patient sub-populations. Unsupervised multivariate analysis of cytokine profiles quantified by multiplex immunoassays identified a subset of patients with a shared “consensus signature” of thirteen elevated cytokines that was associated with common clinical features, but was not observed among patient subpopulations defined by morphologic presentation alone. Enrichment analysis of consensus markers reinforced the primacy of peritoneal macrophage infiltration and activation, which was demonstrably elevated in ex vivo cultures. Although familiar targets of the NFκB family emerged among over-represented transcriptional binding sites for consensus markers, our analysis provides evidence for a previously unrecognized contribution from c-Jun, c-Fos, and AP-1 effectors of mitogen associated kinase signaling. Their crucial involvement in propagation of macrophage-driven inflammatory networks was confirmed via targeted inhibition of upstream kinases. Collectively, these analyses provide in vivo validation of a clinically relevant inflammatory network that may serve as an objective measure for guiding treatment decisions for endometriosis management, and in the future may provide a mechanistic endpoint for assessing efficacy of novel agents aimed at curtailing inflammatory mechanisms that drive disease progression. PMID:24500404

  11. An update on renal involvement in hemophagocytic syndrome (macrophage activation syndrome)

    PubMed Central

    Esmaili, Haydarali; Mostafidi, Elmira; Mehramuz, Bahareh; Ardalan, Mohammadreza; Mohajel-Shoja, Mohammadali

    2016-01-01

    Context: Hemophagocytic syndrome (HPS) is mainly characterized by massive infiltration of bone marrow by activated macrophages and often presents with pancytopenia. Thrombotic microangiopathy (TMA) is also present with thrombocytopenia and renal involvement. Both conditions could coexist with each other and complicate the condition. Evidence Acquisition: Directory of Open Access Journals (DOAJ), EMBASE, Google Scholar, PubMed, EBSCO, and Web of Science with keywords relevant to; Hemophagocytic syndrome, macrophage activation syndrome, interferon-gamma and thrombotic microangiopathy, have been searched. Results: Viral infection, rheumatologic disease and malignancies are the main underlying causes for secondary H