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Sample records for monocyte chemotactic factor

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

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    Grob, P.M.; David, E.; Warren, T.C.; DeLeon, R.P.; Farina, P.R.; Homon, C.A. (Boehringer Ingelheim Pharmaceuticals, Inc., Ridgefield, CT (USA))

    1990-05-15

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

  2. Human recombinant macrophage inflammatory protein-1 alpha and -beta and monocyte chemotactic and activating factor utilize common and unique receptors on human monocytes.

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    Wang, J M; Sherry, B; Fivash, M J; Kelvin, D J; Oppenheim, J J

    1993-04-01

    The human macrophage inflammatory proteins-1 alpha and -beta (MIP-1 alpha and -beta), which are also known as LD78 and ACT2, respectively, are distinct but highly related members of the chemoattractant cytokine (chemokine) family. rMIP-1 alpha and -beta labeled with 125I specifically bind to human peripheral blood monocytes, the monocytic cell line THP-1, peripheral blood T cells, and the YT cell line. Steady state binding experiments revealed approximately 3000 high affinity binding sites/cell for MIP-1 alpha on human monocytes and on THP-1 cells, with Kd values of 383 pM and 450 pM, respectively. Human MIP-1 alpha and -beta had nearly identical affinities for the binding sites and each competed equally well for binding. Human monocyte chemotactic and activating factor (MCAF), a member of the same chemokine family, consistently displaced about 25% of human MIP-1 alpha and -beta binding on monocytes but not on YT cells, which did not bind MCAF. On the other hand, human rMIP-1 alpha and -beta partially inhibited binding of radiolabeled MCAF to monocytes. Both MIP-1 alpha and -beta were chemotactic for human monocytes. Preincubation of monocytes with human rMIP-1 alpha or -beta markedly reduced cell migration towards the other cytokine, whereas preincubation with human rMCAF only partially desensitized the monocyte chemotaxis response to human rMIP-1 alpha or -beta. These data suggest the existence of three subtypes of receptors, i.e., one unique receptor shared by MIP-1 alpha and -beta, a second unique receptor for MCAF, and a third species that recognizes both MCAF and MIP-1 peptides.

  3. Plasma Levels of Monocyte Chemotactic Protein 3 and Beta-Nerve Growth Factor Increase with Amnestic Mild Cognitive Impairment

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    Kang Soo Lee; Ji Hyung Chung; Kyung Hye Lee; Min-Jeong Shin; Byoung Hoon Oh; Soo Hyung Lee; Chang Hyung Hong

    2009-01-01

    A number of studies have investigated peripheral inflammatory indices, including plasma cytokines and related molecules according to subtypes of dementia, but not in mild cognitive impairment (MCI). In this study, we used multiplex cytokine assay to assess the plasma levels of 22 cytokines in patients with MCI subtyped as amnestic and non-amnestic, according to cognitive features. When comparing the levels of plasma growth factors, chemokines and cytokines, plasma levels of monocyte chemotactic protein 3 (MCP-3), and beta-nerve growth factor (β-NGF) in these two groups, they were found to be significantly higher in amnestic MCI patients than in non-amnestic MCI patients, after adjusting for age and gender. This suggests that plasma MCP-3 and β-NGF may be useful in differentiating subtypes of MCI. Cellular & Molecular Immunology.

  4. Monocyte chemotactic protein-1 gene polymorphism and spontaneous bacterial peritonitis

    Institute of Scientific and Technical Information of China (English)

    Levent; Filik

    2010-01-01

    I read with great interest the article by Gbele et al published in issue 44 of World J Gastroenterol 2009.The results of their study indicate that-2518 Monocyte chemotactic protein-1(MCP-1)genotype AA is a risk factor for spontaneous bacterial peritonitis in patients with alcoholic cirrhosis.However,there are some items that need to be discussed.

  5. Urotensin II is a new chemotactic factor for UT receptor-expressing monocytes.

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    Segain, Jean-Pierre; Rolli-Derkinderen, Malvyne; Gervois, Nadine; Raingeard de la Blétière, Diane; Loirand, Gervaise; Pacaud, Pierre

    2007-07-15

    Urotensin II (U-II), a vasoactive cyclic neuropeptide which activates the G protein-coupled receptor UT receptor, exerts various cardiovascular effects and may play a role in the pathophysiology of atherosclerosis. In this study, we report that the UT receptor is expressed and functional on human PBMC and rat splenocytes. PBMC surface expression of the UT receptor was mainly found in monocytes and NK cells, also in a minority of B cells, but not in T cells. Stimulation of monocytes with LPS increased UT receptor mRNA and protein expression. Cloning and functional characterization of the human UT receptor gene promoter revealed the presence of NF-kappaB-binding sites involved in the stimulation of UT receptor gene expression by LPS. Activation of the UT receptor by U-II induced chemotaxis with maximal activity at 10 and 100 nM. This U-II effect was restricted to monocytes. Analysis of the signaling pathway involved indicated that U-II-mediated chemotaxis was related to RhoA and Rho kinase activation and actin cytoskeleton reorganization. The present results thus identify U-II as a chemoattractant for UT receptor-expressing monocytes and indicate a pivotal role of the RhoA-Rho kinase signaling cascade in the chemotaxis induced by U-II.

  6. Minimally modified low density lipoprotein induces monocyte chemotactic protein 1 in human endothelial cells and smooth muscle cells

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    Cushing, S.D.; Berliner, J.A.; Valente, A.J.; Territo, M.C.; Navab, M.; Parhami, F.; Gerrity, R.; Schwartz, C.J.; Fogelman, A.M.

    1990-07-01

    After exposure to low density lipoprotein (LDL) that had been minimally modified by oxidation (MM-LDL), human endothelial cells (EC) and smooth muscle cells (SMC) cultured separately or together produced 2- to 3-fold more monocyte chemotactic activity than did control cells or cells exposed to freshly isolated LDL. This increase in monocyte chemotactic activity was paralleled by increases in mRNA levels for a monocyte chemotactic protein 1 (MCP-1) that is constitutively produced by the human glioma U-105MG cell line. Antibody that had been prepared against cultured baboon smooth muscle cell chemotactic factor (anti-SMCF) did not inhibit monocyte migration induced by the potent bacterial chemotactic factor f-Met-Leu-Phe. However, anti-SMCF completely inhibited the monocyte chemotactic activity found in the media of U-105MG cells, EC, and SMC before and after exposure to MM-LDL. Moreover, monocyte migration into the subendothelial space of a coculture of EC and SMC that had been exposed to MM-LDL was completely inhibited by anti-SMCF. Anti-SMCF specifically immunoprecipitated 10-kDa and 12.5-kDa proteins from EC. Incorporation of (35S)methionine into the immunoprecipitated proteins paralleled the monocyte chemotactic activity found in the medium of MM-LDL stimulated EC and the levels of MCP-1 mRNA found in the EC. We conclude that SMCF is in fact MCP-1 and MCP-1 is induced by MM-LDL.

  7. Growth Factors: Production of Monocyte Chemotactic Protein-1 (MCP-1/JE) by Bone Marrow Stromal Cells: Effect on the Migration and Proliferation of Hematopoietic Progenitor Cells.

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    Xu, Y. X.; Talati, B. R.; Janakiraman, N.; Chapman, R. A.; Gautam, S. C.

    1999-01-01

    Recombinant chemotactic cytokines (chemokines) have been shown to modulate in vitro proliferation of hematopoietic progenitor cells. Whether bone marrow stromal cells produce chemokines and the physiological role they may have in the regulation of hematopoiesis has largely remained unexamined. We have examined the expression of monocyte chemoattractant protein-1 (MCP-1/JE) in bone marrow stromal cells and its effect on the migration and proliferation of murine hematopoietic progenitor cells. Freshly derived murine bone marrow stromal cells were found to secrete abundant amounts of MCP-1/JE, which was further increased upon stimulation of stromal cells with pro-inflammatory agents LPS, IL1-alpha, IFN-gamma, or TNF-alpha. Although culture supernatant conditioned by stromal cells exhibited chemotactic activity toward hematopoietic progenitor cells, the chemotactic activity was not due to MCP-1/JE. Furthermore, rMCP-1/JE also failed to induce migration of progenitor cells. MCP-1/JE, however, caused 20 to 30% increase in the clonal expansion of progenitor cells. Thus, although MCP-1/JE does not chemoattract hematopoietic progenitor cells it may have a role in their proliferation and clonal expansion.

  8. Roles of monocyte chemotactic protein 1 and nuclear factor-κB in immune response to spinal tuberculosis in a New Zealand white rabbit model

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    Guo, X.H.; Bai, Z.; Qiang, B.; Bu, F.H.; Zhao, N.

    2017-01-01

    This study aimed to explore the roles of monocyte chemotactic protein 1 (MCP-1) and nuclear factor kappa B (NF-κB) in immune response to spinal tuberculosis in a New Zealand white rabbit model. Forty-eight New Zealand white rabbits were collected and divided into four groups: experimental group (n=30, spinal tuberculosis model was established), the sham group (n=15, sham operation was performed) and the blank group (n=3). The qRT-PCR assay and western blotting were applied to detect the mRNA and protein expressions of MCP-1 and NF-κB in peripheral blood. ELISA was used to measure serum levels of MCP-1, NF-κB, IFN-γ, IL-2, IL-4, and IL-10. Flow cytometry was adopted to assess the distributions of CD4+, CD8+ lymphocytes and CD4+ CD25+ Foxp3 lymphocyte subsets. Compared with the sham and blank groups, the mRNA and protein expressions of MCP-1 and NF-κB in the experimental group were significantly increased. The experimental group had lower serum levels of IL-2 and IFN-γ and higher serum level of IL-10 than the sham and blank groups. In comparison to the sham and blank groups, CD4+ T lymphocyte subsets percentage, CD4+/CD8+ ratio and CD4+ CD25+ Foxp3+ Tregs subsets accounting for CD4+ lymphocyte in the experimental group were lower, while percentage of CD8+ T lymphocyte subsets was higher. Our study provided evidence that higher expression of MCP-1 and NF-κB may be associated with decreased immune function of spinal tuberculosis, which can provide a new treatment direction for spinal tuberculosis. PMID:28225889

  9. Monocyte chemotactic protein-1 deficiency reduces spontaneous metastasis of Lewis lung carcinoma in mice fed a high-fat diet

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    Obesity is a risk factor for cancer. Adipose tissue produces pro-inflammatory adipokines that contribute obesity-related malignant progression. This study investigated the effects of monocyte chemotactic protein-1 (MCP-1) deficiency on pulmonary metastasis of Lewis lung carcinoma (LLC) in male C57...

  10. Directed migration of human neural progenitor cells to interleukin-1β is promoted by chemokines stromal cell-derived factor-1 and monocyte chemotactic factor-1 in mouse brains

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    Wu Yumei

    2012-07-01

    Full Text Available Abstract Background Neurogenesis, including the proliferation, migration and differentiation of neural progenitor cells (NPCs, is impaired in HIV-1 associated dementia (HAD. We previously demonstrated HIV-1-infected macrophages (HIV-MDM regulate stromal cell-derived factor 1 (SDF-1 production in astrocytes through Interleukin-1β (IL-1β. Chemokines are known to induce NPC migration; however, it remains unclear how chemokines produced in inflammation regulate NPC migration. Methods The secretion of SDF-1 and Monocyte chemotactic preotein-1 (MCP-1 in astrocytes upon IL-1β stimulation was measured by ELISA assay. Human NPCs were injected parallel along with IL-1β, SDF-1 or MCP-1 intracranially into basal ganglion 1 mm apart in SCID mice, and immunofluorescent staining was used to study the survival and migration of injected human NPCs. Results SDF-1 and MCP-1 are secreted by astrocytes upon IL-1β stimulation in a time-dependent manner. Injected human NPCs survived in SCID mice and migrated towards sites of IL-1β, SDF-1 and MCP-1 injection. Conclusions In conclusion, chemokines SDF-1 or MCP-1 secreted by astrocytes in the presence of IL-1β injection are attractive to NPCs injected into SCID mouse brains, suggesting that SDF-1 and MCP-1 play important roles in NPC migration during neuroinflammation.

  11. Minimally modified low density lipoprotein induces monocyte chemotactic protein 1 in human endothelial cells and smooth muscle cells.

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    Cushing, S D; Berliner, J A; Valente, A. J.; Territo, M C; Navab, M; Parhami, F; Gerrity, R; Schwartz, C J; Fogelman, A M

    1990-01-01

    After exposure to low density lipoprotein (LDL) that had been minimally modified by oxidation (MM-LDL), human endothelial cells (EC) and smooth muscle cells (SMC) cultured separately or together produced 2- to 3-fold more monocyte chemotactic activity than did control cells or cells exposed to freshly isolated LDL. This increase in monocyte chemotactic activity was paralleled by increases in mRNA levels for a monocyte chemotactic protein 1 (MCP-1) that is constitutively produced by the human ...

  12. Monocyte chemotactic protein-1 expression in coronary atherosclerosis plaque of sudden coronary death patients

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    冯相平

    2006-01-01

    Objective To investigate the expression of monocyte chemotactic protein 1 (MCP-1) in coronary atherosclerosis plaque of sudden coronary death (SCD) patients and the relationship between MCP-1 expression and SCD. Methods Autopsy heart samples (n=90) collected during 2001 - 2003 were divided to SCD group (n=

  13. Monocyte Chemotactic Protein-1 Promotes the Myocardial Homing of Mesenchymal Stem Cells in Dilated Cardiomyopathy

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    Yunzeng Zou

    2013-04-01

    Full Text Available Dilated cardiomyopathy (DCM is the most common form of non-ischemic cardiomyopathy that leads to heart failure. Mesenchymal stem cells (MSCs are under active investigation currently as a potential therapy for DCM. However, little information is available about the therapeutic potential of intravenous administration of MSCs for DCM. Moreover, how MSCs home to the myocardium in DCM is also unclear. DCM was induced by intraperitoneally administering Doxorubicin and MSCs or vehicles were infused through the internal jugular vein. Cardiac functions including the percentage of fractional shortening, left ventricular diastolic dimension, left ventricular end-diastolic pressure, and left ventricular maximum dp/dt were evaluated by echocardiographic and hemodynamic studies. Fibrosis was determined by Masson’s trichrome staining. The mRNA expression levels of monocyte chemotactic protein-1 (MCP-1, stromal cell-derived factor-1 (SDF-1, macrophage inflammatory protein-1α (MIP-1α, and monocyte chemotactic protein-3 (MCP-3 were determined using real time polymerase chain reactions and the protein expression level of MCP-1 was detected with Western blot. The MSCs expression of C-C chemokine receptor type 2 (CCR2, a MCP-1 receptor, was confirmed by Western blot and flow cytometry analysis. The chemotactic effects of MCP-1/CCR2 were checked by assessing the migration in vitro and in vivo. MSCs transplantation improved the cardiac function and decreased the myocardial fibrosis of mice with DCM. MCP-1 was up-regulated in dilated myocardial tissue both at the mRNA and protein level while SDF-1, MIP-1α and MCP-3 remain unchanged. CCR2 was present in MSCs. MCP-1 promoted MSCs migration in vitro while CCR2 inhibition decreased the migration of MCP-1 to the dilated heart. This study provides direct evidences that peripheral intravenous infusion of MSCs can support the functional recovery of DCM. In addition, novel insights into the myocardial homing factor of MSCs

  14. Effect of monocyte chemoattractant protein-1 on chemotactic gene expression by macrophage cell line U937

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    BIAN Guang-xing; GUO Bao-yu; MIAO Hong; QIU Lei; CAO Dong-mei; DAO Shu-yan; ZHANG Ran

    2004-01-01

    Objective: To study the chemotactic superfamily genes expression profiling of macrophage line U937 treated with monocyte chemoattractant protein-1 (MCP-1) using gene chip technique. Methods: Total RNA from macrophage line U937 (as control) and U937 with MCP-1 was extracted, made reverse transcript to cDNA and tested with gene expression chip HO2 human. Results: Some chemotactic-related gene expressions were changed in all analyzed genes. Regulated upon activation, normal T cell expressed and secreted (RANTES) was up-regulated over 2-fold and 7 chemotactic-related genes (CCR2, CCR5, CCL16, GROβ, GROγ, IL-8 and granulocyte chemotactic protein 2) were down-regulated over 2-fold inMCP-1 treated U937 cells at mRNA level. Conclusion: MCP-1 can influence some chemokines and receptors expression in macrophage in vitro, in which MCP-1 mainly down-regulates the chemotactic genes expression of those influencing neutrophilic granulocyte (GROβ, GROγ, IL-8 and granulocyte chemotactic protein 2). Another novel finding is that it can also down-regulate the mRNA level of CCR5, which plays a critical role in many disorders and illnesses.

  15. Monocyte chemotactic protein-1 and other inflammatory parameters in Bernese Mountain dogs with disseminated histiocytic sarcoma.

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    Nikolic Nielsen, Lise; Kjelgaard-Hansen, Mads; Kristensen, Annemarie T

    2013-11-01

    The interaction between cancer and the immune system, and the production of cytokines by the tumour itself have been associated with altered levels of cytokines in human cancer patients. Bernese Mountain dogs with disseminated histiocytic sarcoma (DHS) show vague and non-specific clinical signs. Although histiocytes can secrete cytokines in response to inflammatory stimuli, serum cytokine concentrations in dogs with DHS have not previously been investigated. The aim of this study was to evaluate the immunological state of untreated Bernese Mountain dogs with DHS by assessing multiple serum cytokines and to correlate these with other inflammatory markers. As a prospective case control study, 17 Bernese Mountain dogs with DHS were included along with 18 healthy controls (12 Bernese Mountain dogs and 6 dogs of various breeds). Blood samples were examined for fibrinogen, C-reactive protein (CRP), white blood cell count, monocyte count and the following cytokines: interleukin (IL)-6, IL-10, IL-12, IL-15, IL-18, tumour necrosis factor and monocyte chemotactic protein (MCP)-1. Significant differences were observed in Bernese Mountain dogs with DHS compared to healthy control dogs for fibrinogen (P=0.002), CRP (P=0.02) and MCP-1 (P=0.004). Other important pro-inflammatory cytokines were not significantly increased in dogs with DHS and none of the measured cytokines were correlated to either WBC, monocyte count, CRP or fibrinogen concentration. The implications of this increased MCP-1 blood levels in Bernese Mountain dogs with DHS warrant further investigations. Copyright © 2013 Elsevier Ltd. All rights reserved.

  16. Plasma monocyte chemotactic protein-1 remains elevated after minimally invasive colorectal cancer resection.

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    Shantha Kumara, H M C; Myers, Elizabeth A; Herath, Sonali Ac; Jang, Joon Ho; Njoh, Linda; Yan, Xiaohong; Kirchoff, Daniel; Cekic, Vesna; Luchtefeld, Martin; Whelan, Richard L

    2014-10-15

    To investigate plasma Monocyte Chemotactic Protein-1 levels preoperatively in colorectal cancer (CRC) and benign patients and postoperatively after CRC resection. A plasma bank was screened for minimally invasive colorectal cancer resection (MICR) for CRC and benign disease (BEN) patients for whom preoperative, early postoperative, and 1 or more late postoperative samples (postoperative day 7-27) were available. Monocyte chemotactic protein-1 (MCP-1) levels (pg/mL) were determined via enzyme linked immuno-absorbent assay. One hundred and two CRC and 86 BEN patients were studied. The CRC patient's median preoperative MCP-1 level (283.1, CI: 256.0, 294.3) was higher than the BEN group level (227.5, CI: 200.2, 245.2; P = 0.0004). Vs CRC preoperative levels, elevated MCP-1 plasma levels were found on postoperative day 1 (446.3, CI: 418.0, 520.1), postoperative day 3 (342.7, CI: 320.4, 377.4), postoperative day 7-13 (326.5, CI: 299.4, 354.1), postoperative day 14-20 (361.6, CI: 287.8, 407.9), and postoperative day 21-27 (318.1, CI: 287.2, 371.6; P MICR for CRC, MCP-1 levels were elevated for 1 mo and may promote angiogenesis, cancer recurrence and metastasis.

  17. Eosinophil chemotactic factors from cysticercoids of Hymenolepis nana.

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    Niwa, A; Asano, K; Ito, A

    1998-09-01

    A comparative study of eosinophil chemotactic factors was carried out using cysticercoids and oncospheres of Hymenolepis nana. Cysticercoids showed twice the chemotactic activity for eosinophils than the oncospheres. Eosinophilia induced by oncospheres and cysticercoids observed in secondary and primary infections, respectively, were discussed from the view point of the immunobiology of this parasite.

  18. Effect of Monocyte Chemotactic Protein-1 on the Intraperitoneal Adhesion Formation

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    In order to study the role of monocyte chemotactic protein-1 (MCP-1) in the intra-peritoneal adhesion formation, 23 infertile patients undergoing laparoscopic operation were divided into two groups: experimental group including 12 patients with intra-peritoneal adhesion and control group including 11 patients without intra-peritoneal adhesion. Peritoneal fluid (PF) and peritoneum were collected from these patients during laparoscopic examination. The expression levels of MCP-l protein and MCP-1 mRNA were detected by using enzyme-linked immunosorbent assay (ELISA) and dot blot analysis method respectively. It was found that the levels of MCP-1 protein in PF of the patients with peritoneal adhesion were significantly higher than in the control group (0. 44±0.11 ng/ml vs 0. 19+0. 09 ng/ml respectively, P<0. 01 ). The level of MCP-1 mRNA in the peritoneum of the patients with peritoneal adhesion was significantly higher than in the control group (48.61±3.72 vs 19. 87±2.54 respectively, P<0. 01). It was suggested that MCP-1 might play a role in the adhesion formation, and chemotactic cytokines expressing in the peritoneal mesothelial cells might be take part in the process.

  19. Biological characterization of purified macrophage-derived neutrophil chemotactic factor

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    M. Dias-Baruffi

    1995-01-01

    Full Text Available We have recently described the purification of a 54 kDa acidic protein, identified as macrophage-derived neutrophil chemotactic factor (MNCF. This protein causes in vitro chemotaxis as well as in vivo neutrophil migration even in animals treated with dexamethasone. This in vivo chemotactic activity of MNCF in animals pretreated with dexamethasone is an uncommon characteristic which discriminates MNCF from known chemotactic cytokines. MNCF is released in the supernatant by macrophage monolayers stimulated with lipopolysaccharide (LPS. In the present study, we describe some biological characteristics of homogenous purified MNCF. When assayed in vitro, MNCF gave a bell-shaped dose–response curve. This in vitro activity was shown to be caused by haptotaxis. Unlike N-formyl-methionylleucyl- phenylalanine (FMLP or interleukin 8 (IL-8, the chemotactic activity of MNCF in vivo and in vitro, was inhibited by preincubation with D-galactose but not with D-mannose. In contrast with IL-8, MNCF did not bind to heparin and antiserum against IL-8 was ineffective in inhibiting its chemotactic activity. These data indicate that MNCF induces neutrophil migration through a carbohydrate recognition property, but by a mechanism different from that of the known chemokines. It is suggested that MNCF may be an important mediator in the recruitment of neutrophils via the formation of a substrate bound chemotactic gradient (haptotaxis in the inflamed tissues.

  20. Cryptic chemotactic activity of fibronectin for human monocytes resides in the 120-kDa fibroblastic cell-binding fragment.

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    Clark, R A; Wikner, N E; Doherty, D E; Norris, D A

    1988-08-25

    Monocytes and lymphocytes form a second wave of infiltrating blood leukocytes in areas of tissue injury. The mechanisms for monocyte accumulation at these sites are not completely understood. Recently, however, fragments from extracellular matrix proteins including collagen, elastin, and fibronectin have been shown to induce monocyte chemotaxis. In this report we demonstrate that chemotactic activity for human monocytes is expressed when a 120-kDa fragment containing the RGDS cell-binding peptide is released from intact fibronectin or from larger fibronectin fragments. Monocytes, either from mononuclear cell Ficoll-Hypaque preparations (10-20% monocytes, 89-90% lymphocytes) or from elutriation preparations (95% monocytes, 5% lymphocytes), but not lymphocytes, migrated toward 120-kDa fragment preparations (10(-7) M) in blind-end chambers when the cells were separated from the chemoattractant by a 5-micron pore polycarbonate filter either alone or overlying a 0.45-micron pore nitrocellulose filter. Neutrophils migrated toward zymosan-activated serum but not toward 10(-5)-10(-8) M concentrations of the 120-kDa fragment. Intact fibronectin had no chemotactic activity for human monocytes. Fibronectin was isolated from citrated human plasma by sequential gelatin-Sepharose affinity and DEAE ion-exchange chromatography in the presence of buffers containing 1 mM phenylmethylsulfonyl fluoride to prevent fragmentation. Controlled enzymatic digestion with thermolysin cleaved fibronectin into 30 kDa fibrin, 45 kDa collagen, and 150/160-kDa cell and heparin domains. Upon prolonged digestion, purified 150/160-kDa fragments were cleaved into 120-kDa cell and 30/40-kDa heparin-binding fragments. Even though the intact fibronectin molecule, the 150/160-kDa fragments, and the 120-kDa fragment, have cell binding activity for Chinese hamster ovary fibroblasts, only the 120-kDa fragment expressed chemotactic activity for human monocytes. Thus, the 120-kDa fibroblastic cell

  1. Adrenergic regulation of monocyte chemotactic protein 1 leads to enhanced macrophage recruitment and ovarian carcinoma growth

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    Armaiz-Pena, Guillermo N.; Gonzalez-Villasana, Vianey; Nagaraja, Archana S.; Rodriguez-Aguayo, Cristian; Sadaoui, Nouara C.; Stone, Rebecca L.; Matsuo, Koji; Dalton, Heather J.; Previs, Rebecca A.; Jennings, Nicholas B.; Dorniak, Piotr; Hansen, Jean M.; Arevalo, Jesusa M.G.; Cole, Steve W.; Lutgendorf, Susan K.; Sood, Anil K.; Lopez-Berestein, Gabriel

    2015-01-01

    Increased adrenergic signaling facilitates tumor progression, but the underlying mechanisms remain poorly understood. We examined factors responsible for stress-mediated effects on monocyte/macrophage recruitment into the tumor microenvironment, and the resultant effects on tumor growth. In vitro, MCP1 was significantly increased after catecholamine exposure, which was mediated by cAMP and PKA. Tumor samples from mice subjected to daily restraint stress had elevated MCP1 gene and protein levels, increased CD14+ cells, and increased infiltration of CD68+ cells. hMCP1 siRNA-DOPC nanoparticles significantly abrogated daily restraint stress-induced tumor growth and inhibited infiltration of CD68+ and F4/80+ cells. In ovarian cancer patients, elevated peripheral blood monocytes and tumoral macrophages were associated with worse overall survival. Collectively, we demonstrate that increased adrenergic signaling is associated with macrophage infiltration and mediated by tumor cell-derived MCP1 production. PMID:25738355

  2. Organ-specific chemotactic factors present in lung extracellular matrix.

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    Cerra, R F; Nathanson, S D

    1989-05-01

    The preferential colonization of a distant organ by a circulating tumor cell (organ specific metastasis) may be regulated by chemotactic factors present within the extracellular matrix of the host organ. Organ-specific extracellular matrix was prepared from murine kidney and lung by high salt extraction and DNAase/RNAase digestion. A soluble protein fraction (S2) from each of the matricies was obtained by 4 M guanidine extraction and was tested for organ-specific chemotactic activity in a modified Boyden chamber. The lung colonizing B16-F10 and B16-BL6 tumor cell lines demonstrated organ-specific motility only toward the lung extract. The low metastasizing B16 parental line and liver colonizing B16-L4b line showed no preference for either lung or kidney. The lung activity resolves into five fractions by gel filtration chromatography, with the highest activity eluting at Mr approximately 71,000. Chemotactic factors present in lung extracellular matrix may regulate the preferential colonization of an organ by stimulating the migration of tumor cells in a specific manner. These factors may be released during the degradation of the extracellular matrix.

  3. Monocyte chemotactic protein-1 attenuates and high-fat diet exacerbates bone loss in mice with pulmonary metastasis of Lewis lung carcinoma

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    Bone can be adversely affected by obesity and cancer-associated complications including wasting. The objective of this study was to determine whether a high-fat diet and a deficiency in monocyte chemotactic protein-1 (MCP-1) altered bone structural defects found in male C57BL/6 mice with Lewis lung...

  4. Down-regulation of the chemokine receptor CCR5 by activation of chemotactic formyl peptide receptor in human monocytes.

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    Shen, W; Li, B; Wetzel, M A; Rogers, T J; Henderson, E E; Su, S B; Gong, W; Le, Y; Sargeant, R; Dimitrov, D S; Oppenheim, J J; Wang, J M

    2000-10-15

    Interactions between cell surface receptors are important regulatory elements in the complex host responses to infections. In this study, it is shown that a classic chemotactic factor, the bacterial chemotactic peptide N-formyl-methionyl-leucylphenyl-alanine (fMLF), rapidly induced a protein-kinase-C-mediated serine phosphorylation and down-regulation of the chemokine receptor CCR5, which serves as a major human immunodeficiency virus (HIV)-1 coreceptor. The fMLF binding to its receptor, formyl peptide receptor (FPR), resulted in significant attenuation of cell responses to CCR5 ligands and in inhibition of HIV-1-envelope-glycoprotein-mediated fusion and infection of cells expressing CD4, CCR5, and FPR. The finding that the expression and function of CCR5 can be regulated by peptides that use an unrelated receptor may provide a novel approach to the design of anti-inflamatory and antiretroviral agents. (Blood. 2000;96:2887-2894)

  5. Monocyte transmigration induced by modification of low density lipoprotein in cocultures of human aortic wall cells is due to induction of monocyte chemotactic protein 1 synthesis and is abolished by high density lipoprotein.

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    Navab, M; Imes, S S; Hama, S Y; Hough, G P; Ross, L.A.; Bork, R W; Valente, A. J.; Berliner, J A; Drinkwater, D C; Laks, H

    1991-01-01

    Incubation of cocultures of human aortic endothelial (HAEC) and smooth muscle cells (HASMC) with LDL in the presence of 5-10% human serum resulted in a 7.2-fold induction of mRNA for monocyte chemotactic protein 1 (MCP-1), a 2.5-fold increase in the levels of MCP-1 protein in the coculture supernatants, and a 7.1-fold increase in the transmigration of monocytes into the subendothelial space of the cocultures. Monocyte migration was inhibited by 91% by antibody to MCP-1. Media collected from t...

  6. Plasma Levels of Monocyte Chemotactic Protein-1 Are Associated with Clinical Features and Angiogenesis in Patients with Multiple Myeloma

    Directory of Open Access Journals (Sweden)

    Toni Valković

    2016-01-01

    Full Text Available The aim of this pilot study was to determine the plasma levels of monocyte chemotactic protein-1 (MCP-1 and possible associations with angiogenesis and the main clinical features of untreated patients with multiple myeloma (MM. ELISA was used to determine plasma MCP-1 levels in 45 newly diagnosed MM patients and 24 healthy controls. The blood vessels were highlighted by immunohistochemical staining, and computer-assisted image analysis was used for more objective and accurate determination of two parameters of angiogenesis: microvessel density (MVD and total vascular area (TVA. The plasma levels of MCP-1 were compared to these parameters and the presence of anemia, renal dysfunction, and bone lesions. A significant positive correlation was found between plasma MCP-1 concentrations and TVA (p=0.02. The MCP-1 levels were significantly higher in MM patients with evident bone lesions (p=0.01, renal dysfunction (p=0.02, or anemia (p=0.04. Therefore, our preliminary results found a positive association between plasma MCP-1 levels, angiogenesis (expressed as TVA, and clinical features in patients with MM. However, additional prospective studies with a respectable number of patients should be performed to authenticate these results and establish MCP-1 as a possible target of active treatment.

  7. Monocyte chemotactic protein-1 deficiency attenuates and high-fat diet exacerbates bone loss in mice with Lewis lung carcinoma.

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    Yan, Lin; Nielsen, Forrest H; Sundaram, Sneha; Cao, Jay

    2017-04-04

    Bone loss occurs in obesity and cancer-associated complications including wasting. This study determined whether a high-fat diet and a deficiency in monocyte chemotactic protein-1 (MCP-1) altered bone structural defects in male C57BL/6 mice with Lewis lung carcinoma (LLC) metastases in lungs. Compared to non-tumor-bearing mice, LLC reduced bone volume fraction, connectivity density, trabecular number, trabecular thickness and bone mineral density and increased trabecular separation in femurs. Similar changes occurred in vertebrae. The high-fat diet compared to the AIN93G diet exacerbated LLC-induced detrimental structural changes; the exacerbation was greater in femurs than in vertebrae. Mice deficient in MCP-1 compared to wild-type mice exhibited increases in bone volume fraction, connectivity density, trabecular number and decreases in trabecular separation in both femurs and vertebrae, and increases in trabecular thickness and bone mineral density and a decrease in structure model index in vertebrae. Lewis lung carcinoma significantly decreased osteocalcin but increased tartrate-resistant acid phosphatase 5b (TRAP 5b) in plasma. In LLC-bearing mice, the high-fat diet increased and MCP-1 deficiency decreased plasma TRAP 5b; neither the high-fat diet nor MCP-1 deficiency resulted in significant changes in plasma concentration of osteocalcin. In conclusion, pulmonary metastasis of LLC is accompanied by detrimental bone structural changes; MCP-1 deficiency attenuates and high-fat diet exacerbates the metastasis-associated bone wasting.

  8. Radioassay of granulocyte chemotaxis. Studies of human granulocytes and chemotactic factors. [/sup 51/Cr tracer technique

    Energy Technology Data Exchange (ETDEWEB)

    Gallin, J.I.

    1974-01-01

    The above studies demonstrate that the /sup 51/Cr radiolabel chemotactic assay is a relatively simple and objective means for studying leukocyte chemotaxis in both normal and pathological conditions. Application of this method to studies of normal human chemotaxis revealed a relatively narrow range of normal and little day-to-day variability. Analysis of this variability revealed that there is more variability among the response of different granulocytes to a constant chemotactic stimulus than among the chemotactic activity of different sera to a single cell source. Utilizing the /sup 51/Cr radioassay, the abnormal granulocyte chemotactic behavior reported in Chediak-Higashi syndrome and a patient with recurrent pyogenic infections and mucocutaneous candidiasis has been confirmed. The /sup 51/Cr chemotactic assay has also been used to assess the generation of chemotactic activity from human serum and plasma. The in vitro generation of two distinct chemotactic factors were examined; the complement product (C5a) and kallikrein, an enzyme of the kinin-generating pathway. Kinetic analysis of complement-related chemotactic factor formation, utilizing immune complexes or endotoxin to activate normal sera in the presence or absence of EGTA as well as kinetic analysis of activation of C2-deficient human serum, provided an easy means of distinguishing the classical (antibody-mediated) complement pathway from the alternate pathway. Such kinetic analysis is necessary to detect clinically important abnormalities since, after 60 min of generation time, normal chemotactic activity may be present despite complete absence or inhibition of one complement pathway. The chemotactic factor generated by either pathway of complement activation appears to be predominately attributable to C5a.

  9. Postoperative Changes in Aqueous Monocyte Chemotactic Protein-1 Levels and Bleb Morphology after Trabeculectomy vs. Ex-PRESS Shunt Surgery.

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    Kohei Shobayashi

    Full Text Available To evaluate the postoperative changes in blebs and levels of aqueous monocyte chemotactic protein-1 (MCP-1 after trabeculectomy vs. Ex-PRESS tube shunt surgery.Rabbits were subjected to trabeculectomy or Ex-PRESS tube shunt surgery and observed for up to 3 months. Intraocular pressure (IOP was measured using a rebound tonometer. The MCP-1 level was measured by enzyme-linked immunosorbent assay (ELISA. Bleb morphology was evaluated using photos and anterior-segment optical coherence tomography (OCT.There were no differences in bleb appearance or IOP at any time between the groups. Bleb wall density in the anterior-segment OCT image was significantly lower 1 week after surgery in the Ex-PRESS group than the trabeculectomy group. The MCP-1 level in control eyes was 304.1 ± 45.2 pg/mL. In the trabeculectomy group, the mean aqueous MCP-1 level was 1444.9, 1914.3, 1899.8, 516.4, 398.3, 427.3, 609.5, 1612.7, 386.2, and 167.9 pg/mL at 3, 6, and 12 h, and 1, 2, 5, 7, 14, 30, and 90 days after surgery, respectively. In the Ex-PRESS group, the corresponding values were 1744.0, 1372.0, 932.5, 711.7, 396.1, 487.3, 799.5, 1327.9, 293.6, and 184.0 pg/mL. There were no significant differences in the aqueous MCP-1 level between the groups at any time point.The postoperative changes were similar in the Ex-PRESS and trabeculectomy groups, except for bleb wall density in the anterior-segment OCT image. The postoperative aqueous MCP-1 level had bimodal peaks in both groups.

  10. Adipocyte-derived monocyte chemotactic protein-1 (MCP-1) promotes prostate cancer progression through the induction of MMP-2 activity.

    Science.gov (United States)

    Ito, Yusuke; Ishiguro, Hitoshi; Kobayashi, Naohito; Hasumi, Hisashi; Watanabe, Masatoshi; Yao, Masahiro; Uemura, Hiroji

    2015-07-01

    Obesity is known to be associated with prostate cancer development and progression, but the detailed mechanism is not clear. Monocyte chemotactic protein-1 (MCP-1) is secreted from cancer cells, stromal cells, and adipocytes, and it is involved in prostate cancer progression. Here we investigated the biological role of MCP-1 secreted from adipocytes for prostate cancer cells. Human pre-adipocytes (HPAds) were cultured and differentiated to mature adipocytes. Conditioned medium (CM) from HPAd cells was obtained using phenol red-free RPMI1640 medium. We performed a cytokine membrane array analysis to detect cytokines in the CM. To characterize the physiological function of MCP-1 in the CM, we performed an MTT-assay, a wound-healing and invasion assay with anti-MCP-1 antibody using three prostate cancer cell lines: DU145, LNCaP, and PC-3. Matrix metalloproteinase (MMP)-2 and MMP-9 activities were evaluated by gelatin zymography. A qPCR and Western blotting were used to examine the mRNA and protein expression levels of MMP-2. The cytokine membrane array of the CM showed a strong signal of MCP-1compared to the control medium, and we thus focused our attention on MCP-1 in the CM. The CM up-regulated the cancer cell proliferation, and the neutralization by anti-MCP-1 antibody inhibited the proliferative effect of the prostate cancer cell lines. The CM greatly increased the invasive activity in the prostate cancer cell lines, and anti-MCP-1 antibody decreased the invasiveness. Gelatin zymography revealed that the CM markedly enhanced the enzymatic activity of MMP-2, and anti-MCP-1 antibody down-regulated its effect. MMP-2 mRNA expression was undetected and the MMP-2 protein level was unchanged between the control medium and CM in DU145 cells. MCP-1 from adipocytes enhances the growth and invasion activity of prostate cancer cells. The inhibition of MCP-1 derived from adipocytes might be an effective treatment for prostate cancer. © 2015 Wiley Periodicals, Inc.

  11. Monocyte chemotactic protein 1 increases homing of mesenchymal stem cell to injured myocardium and neovascularization following myocardial infarction

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Objective:To investigate the effect of MCP-1 on mesenchymal stem cells(MSCs) homing to injured myocardium in a rat myocardial infarction(MI) model. Methods:Rat myocardial infarction model was established by permanent left anterior descending branch ligation. Mesenchymal stem cells from donor rats were cultured in IMDM and labeled with BrdU. The Rats were divided into two groups. Monocyte chemotactic protein 1(MCP-1) expression were measured by in situ hybridization and immunohistochemistry in the sham operated or infarcted hearts at 1,2, 4,7,14 and 28 days post operation in MCP-1 detection group. The rats were injected with MCP-1, anti-MCP-1 antibody or saline 4 days after myocardial infarction in intervention group. Then, a total of 5 × 106 cells in 2.5 ml of PBS were injected through the tail vein. The number of the labeled MSCs in the infarcted hearts was counted 3 days post injection. Cardiac function and blood vessel density were assessed 28 days post injection. Results:Self-generating MCP-1 expression was increased at the first day, peaked at the 7th day and decreased thereafter post MI and remained unchanged in sham operated hearts. The MSCs enrichment in the host hearts were more abundant in the MI groups than that in the non-Mi group(P = 0.000), the MSCs enrichment in the host hearts were more abundant in the MCP-1 injected group than that in the anti-MCP-1 antibody and saline injected groups (P = 0.000). Cardiac function was improved more in MCP-1 injected group than anti-MCP-1 antibody and saline injected groups(P= 0.000). Neovascularization in MCP-1 injected group significantly increased compared with that of other groups(P = 0.000). Conclusion: Myocardial MCP-1 expression was increased only in the early phase post MI. MCP-1 may enhance MSCs homing to the injured heart and improve cardiac function by promoting neovascularization.

  12. Corneal organ cultures in tyrosinemia release chemotactic factors.

    Science.gov (United States)

    Lohr, K M; Hyndiuk, R A; Hatchell, D L; Kurth, C E

    1985-05-01

    Corneal inflammation with subsequent scarring and blindness occurs in the inherited human metabolic disease tyrosinemia type II, yet putative inflammatory mediators in this disorder and in the avascular cornea in general are poorly defined. In a Tyr-fed rat model of tyrosinemia type II, intracellular crystals, presumably Tyr, are hypothesized to be responsible for the increased lysosomal activity observed in corneal epithelial lesions. Because polymorphonuclear leukocytes (PMNs) are seen only at the site of these lesions, we used this model to study humoral mediators released from Tyr-fed rat corneal organ cultures. Only Tyr-fed rats developed stromal edema and linear granular opacities in gray edematous corneal epithelium, compatible with a noninfectious keratitis. Electron micrographs confirmed epithelial edema and showed focal epithelial necrosis with PMN invasion of the stroma. Only Tyr-fed rat corneal culture supernatants contained chemotactic activity that was heat labile and moderately trypsin sensitive. Four peaks with varying amounts of chemotactic activity were found on Sephadex G-75 chromatography. Although the identity of these peaks of activity has not yet been established, we suggest that they may be responsible for the PMN infiltration observed in this model of corneal inflammation.

  13. DETECTION OF A NEUTROPHIL CHEMOTACTIC FACTOR IN JAPANESE ENCEPHALITIS PATIENTS

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    Aditi Singh

    2012-12-01

    Full Text Available Japanese encephalitis (JE one of the most common cause of acute encephalitis in tropical regions, has generated much public anxiety in India. An early influx of macrophages followed by neutrophils at the site of injury in different organs in humans and mice has previously been reported. It correlated with production of a neutrophil chemotactic protein derived from macrophages. In the present study out of a total of 324 acute encephalitic patients, admitted in Gandhi memorial and associated hospitals, Lucknow, 121 patients with one or more indicators of JE virus infection were included. Significant pleocytosis (mean TLC value of 126+52 cells / mm3 in CSF and leucocytosis (>11,000 cells/mm3 in peripheral blood was observed at the time of admission. The leucocytosis increased significantly during second week in 67% of patients. The peripheral blood mononuclear cells culture done on alternate days was tested for chemotactic activity (hMDF, which was observed to be highest in second week of illness. The direct detection of hMDF in circulation by dot blot was positive in 92% of acute serum samples, with negligible (12.5% reactivity for convalescent sera. A correlation between the hMDF levels and severity of illness has also been observed.

  14. Gaucher disease: chemotactic factors and immunological cell invasion in a mouse model.

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    Pandey, Manoj Kumar; Jabre, Nicholas A; Xu, You-Hai; Zhang, Wujuan; Setchell, Kenneth D R; Grabowski, Gregory A

    2014-02-01

    Gaucher disease results from mutations in GBA1 that cause functional disruption of the encoded lysosomal enzyme, acid β-glucosidase. The consequent excess accumulation of glucosylceramide and glucosylsphingosine in lysosomes is central to the disease pathogenesis with classical involvement of macrophage (Mфs) lineage cells of visceral organs, bone, or brain. Several studies have implicated the increased secretion of chemokines and infiltration of a variety of immunological cells into tissues of Gaucher disease patients. Trafficking of immunological cells to the sites of inflammation requires the presence of chemokines. Although increases of different immunological cells and several chemokines are present in Gaucher disease, the specific chemoattractants that cause the increased influx of immunological cells are not fully defined. Here, increased levels of I-309, MCP-5, CXCL-2, CXCL-9, CXCL-10, CXCL-11, CXCL-13, and their corresponding leukocytes, i.e., MOs (monocytes), Mфs, dendritic cells (DCs), polymorphonuclear neutrophils (PMNs), and T, and B cells were identified in the circulation of mice with Gba1 mutations (D409V/null). Sera from D409V/null mice contained chemoattractants for a variety of immunological cells as shown by ex vivo chemotaxis studies and by flow cytometry. Enhanced chemotaxis towards 9V/null sera was found for 9V/null lung-, spleen-, liver-, and bone marrow-derived Mфs (CD11b(+) F480(+)), PMNs (Gr1(high) CD11b(+)), DCs (CD11c(+) CD11b(+)), T lymphocytes (CD3(+) TCRB(+)), and B lymphocytes (B220(+) CD19(+)). These data support these chemotactic factors as causative to increased tissue infiltration of leukocytes in Gaucher disease.

  15. Detection of a complement-derived chemotactic factor for tumor cells in human inflammatory and neoplastic effusions.

    Science.gov (United States)

    Orr, F. W.; Delikatny, E. J.; Mokashi, S.; Krepart, G. V.; Stiver, H. G.

    1983-01-01

    A chemotactic factor for neoplastic cells can be generated in vitro by incubating human C5 or C5a with leukocytic or pancreatic lysosomal enzymes and is also detectable in experimental inflammatory exudates. The authors therefore sought evidence for the existence of this factor in human effusions. Using the Boyden chamber assay, they detected chemotactic activity for MB-MDA-231 human breast carcinoma cells and Walker ascites tumor cells in human inflammatory and neoplastic exudates, including ascites, pleural effusions, synovial fluids and cerebrospinal fluids. Chemotactic activity was not found in transudates, normal cerebrospinal fluid, or normal serum. Human ovarian adenocarcinoma cells from one of the effusions migrated toward autologous ascites and towards the C5-derived chemotactic factor that had been prepared in vitro. In gel filtration the chemotactic factor behaved generally as a molecule having a molecular weight of approximately 6000 daltons. The activity was blocked after incubation with antiserums directed against C5 but not by antiserums directed against C3 or C4. In vitro, chemotactic activity for tumor cells could be generated by incubating extracts of exudate cells with autologous plasma or with purified C5. The authors conclude that a chemotactic factor for tumor cells can be formed in human effusions and that this factor has properties similar to those of a previously described C5-derived chemotactic factor. PMID:6185003

  16. Monocyte chemoattractant protein-1 but not tumor necrosis factor-alpha is correlated with monocyte infiltration in mouse lipid lesions

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    Reckless, Jill; Rubin, Edward M.; Verstuyft, Judy B.; Metcalfe, James C.; Grainger, David J.

    1999-01-11

    The infiltration of monocytes into the vascular wall and their transformation into lipid-laden foam cells characterize early atherogenesis. This focal accumulation of lipids, together with smooth muscle cell proliferation and migration, and the synthesis of extracellular matrix in the intima of large arteries result in the formation of an atherosclerotic plaque. The extent to which the plaque is infiltrated with monocytes appears to be an important determinant of plaque stability. It has been proposed that macrophages secrete an excess of matrix-degrading enzymes over their inhibitors, resulting in conversion of a stable plaque into anunstable plaque that is likely to rupture, resulting in acutemyocardial infarction. Macrophages and T cells constitute {approx}40 percent of the total population of cells in the lipid core region of atherosclerotic plaques. Their recruitment to the lesion may depend on alterations in the adhesive properties of the endothelial surface. Increased endothelial cell permeability and endothelial cell activation are among the earliest changes associated with developing lesions of atherosclerosis. Many of the cell adhesion molecules involved in monocyte recruitment are expressed at low or undetectable levels on normal endothelium but are substantially elevated on the endothelium overlaying atherosclerotic lesions In addition to endothelial cell activation, numerous chemotactic cytokines have also been postulated to be involved in monocyte recruitment. For example, interleukin (IL)-1 and tumor necrosis factor-a (TNF-a) are direct chemoattractants for human monocytes but additionally induce cytoskeletal changes in the endothelium that result in increased permeability. This increased permeability, together with stimulated expression of adhesion molecules such as E-selectin, plays an important part in the local inflammation mediated by TNF-a and IL-1. In addition, a large number of other proinflammatory cytokines, including macrophage

  17. Growth factors induce monocyte binding to vascular smooth muscle cells: implications for monocyte retention in atherosclerosis.

    Science.gov (United States)

    Cai, Qiangjun; Lanting, Linda; Natarajan, Rama

    2004-09-01

    Adhesive interactions between monocytes and vascular smooth muscle cells (VSMC) may contribute to subendothelial monocyte-macrophage retention in atherosclerosis. We investigated the effects of angiotensin II (ANG II) and platelet-derived growth factor (PDGF)-BB on VSMC-monocyte interactions. Treatment of human aortic VSMC (HVSMC) with ANG II or PDGF-BB significantly increased binding to human monocytic THP-1 cells and to peripheral blood monocytes. This was inhibited by antibodies to monocyte beta(1)- and beta(2)-integrins. The binding was also attenuated by blocking VSMC arachidonic acid (AA) metabolism by inhibitors of 12/15-lipoxygenase (12/15-LO) or cyclooxygenase-2 (COX-2). Conversely, binding was enhanced by overexpression of 12/15-LO or COX-2. Direct treatment of HVSMC with AA or its metabolites also increased binding. Furthermore, VSMC derived from 12/15-LO knockout mice displayed reduced binding to mouse monocytic cells relative to genetic control mice. Using specific signal transduction inhibitors, we demonstrated the involvement of Src, phosphoinositide 3-kinase, and MAPKs in ANG II- or PDGF-BB-induced binding. Interestingly, after coculture with HVSMC, THP-1 cell surface expression of the scavenger receptor CD36 was increased. These results show for the first time that growth factors may play additional roles in atherosclerosis by increasing monocyte binding to VSMC via AA metabolism and key signaling pathways. This can lead to monocyte subendothelial retention, CD36 expression, and foam cell formation.

  18. Monocyte Chemotactic Protein 1 in Plasma from Soluble Leishmania Antigen-Stimulated Whole Blood as a Potential Biomarker of the Cellular Immune Response to Leishmania infantum

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    Ana V. Ibarra-Meneses

    2017-09-01

    Full Text Available New biomarkers are needed to identify asymptomatic Leishmania infection as well as immunity following vaccination or treatment. With the aim of finding a robust biomarker to assess an effective cellular immune response, monocyte chemotactic protein 1 (MCP-1 was examined in plasma from soluble Leishmania antigen (SLA-stimulated whole blood collected from subjects living in a Leishmania infantum-endemic area. MCP-1, expressed 110 times more strongly than IL-2, identified 87.5% of asymptomatic subjects and verified some asymptomatic subjects close to the cutoff. MCP-1 was also significantly elevated in all patients cured of visceral leishmaniasis (VL, unlike IL-2, indicating the specific memory response generated against Leishmania. These results show MCP-1 to be a robust candidate biomarker of immunity that could be used as a marker of cure and to both select and follow the population in vaccine phase I–III human clinical trials with developed rapid, easy-to-use field tools.

  19. Monocyte chemotactic protein-1 (MCP-1 in patients with chronic schistosomiasis mansoni: evidences of subclinical renal inflammation.

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    Ana Lúcia P Hanemann

    Full Text Available The aim of this study is to investigate renal markers and the biomarker MCP-1 in patients with schistosomiasis mansoni. This is a cross-sectional study with 85 patients aged 5 to 48 years, with a confirmed diagnosis of schistosomiasis mansoni through the Kato-Katz method. The patients were divided in three groups: control (G-I; infected by S. mansoni before treatment (G-II and infected by S. mansoni after treatment (G-III. Renal function was evaluated by tubular and glomerular biomarkers and through urinary MCP-1. Patients' mean age was 23.2 ± 13 years. There was no statistically significant difference between the groups regarding tubular and glomerular function evaluated through the traditional biomarkers. MCP-1 was higher in G-II and G-III, when compared to G-I; p=0.009 and p=0.007, respectively. There was no difference when comparing groups G-II and G-III (p=0.892. Although it was not different among the groups, there was a significant correlation between albuminuria and MCP-1. There was a significant increase in urinary MCP-1 levels in patients with schistosomiasis mansoni, which was associated with albuminuria. This protein has a role in the recruitment of monocytes to injury and inflammation sites . The increase of MCP-1 in the urine evidences that there is silent renal inflammation in these patients and the inflammatory status is not interrupted by specific treatment of the offending agent. Our findings suggest that urinary MCP-1 can be a sensitive marker of renal injury in patients with schistosomiasis mansoni.

  20. Clinical value of detection on serum monocyte chemotactant protein-1 and vascular endothelial cadherin levels in patients with acute cerebral infarction

    Institute of Scientific and Technical Information of China (English)

    Xia Zhou; Cheng Zhang

    2016-01-01

    Objective: To study the correlation of serum monocyte chemotactant protein-1 (MCP-1) and vascular endothelia cadherin (VE-cadherin) levels in patients with acute cerebral infarction, and nerve injury molecules, interleukins and matrix metalloproteinases. Methods: A total of 86 patients with acute cerebral infarction treated in our hospital from April 2012 to October 2015 were selected as the observation group and 50 healthy subjects in the same period treated in our hospital were selected as the control group. The serums were collected and the contents of MCP-1, VE-cadherin, heart-type fatty acid binding protein (H-FABP), S100 calcium binding protein B (S100B), neuron-specific enolase (NSE), interleukin-lb (IL-1b), IL-6, IL-17, IL-18, matrix metalloproteinase-2 (MMP2), MMP3 and MMP9 were measured. Results: The serum contents of MCP-1, VE-cadherin, H-FABP, S100B, NSE, IL-1b, IL-6, IL-17, IL-18, MMP2, MMP3 and MMP9 in observation group were significantly higher than those of control group. Carotid artery plaque formation and unstable plaque properties will increase the serum contents of MCP-1, VE-cadherin, H-FABP, S100B, NSE, IL-1b, IL-6, IL-17, IL-18, MMP2, MMP3 and MMP9 in patients with cerebral infarction. The serum levels of MCP-1, VE-cadherin and the contents of H-FABP, S100B, NSE, IL-1b, IL-6, IL-17, IL-18, MMP2, MMP3 and MMP9 were positively correlated. Conclusions: The serum levels of VE-cadherin and MCP-1 were significantly increased in patients with acute cerebral infarction. MCP-1 and VE-cadherin can increase the secretion of interleukins and matrix metalloproteinases, which can result in the carotid artery plaque formation, unstable plaque properties and the injury of nerve function.

  1. Clinical value of detection on ser um monocyte chemotactant protein-1 and vascular endothelial cadher in levels in patients with acute cerebral infarction

    Directory of Open Access Journals (Sweden)

    Xia Zhou

    2016-11-01

    Full Text Available Objective: To study the correlation of serum monocyte chemotactant protein-1 (MCP-1 and vascular endothelia cadherin (VE-cadherin levels in patients with acute cerebral infarction, and nerve injury molecules, interleukins and matrix metalloproteinases. Methods: A total of 86 patients with acute cerebral infarction treated in our hospital from April 2012 to October 2015 were selected as the observation group and 50 healthy subjects in the same period treated in our hospital were selected as the control group. The serums were collected and the contents of MCP-1, VE-cadherin, heart-type fatty acid binding protein (H-FABP, S100 calcium binding protein B (S100B, neuron-specific enolase (NSE, interleukin-lb (IL-1b, IL-6, IL-17, IL-18, matrix metalloproteinase-2 (MMP2, MMP3 and MMP9 were measured. Results: The serum contents of MCP-1, VE-cadherin, H-FABP, S100B, NSE, IL-1b, IL- 6, IL-17, IL-18, MMP2, MMP3 and MMP9 in observation group were significantly higher than those of control group. Carotid artery plaque formation and unstable plaque properties will increase the serum contents of MCP-1, VE-cadherin, H-FABP, S100B, NSE, IL-1b, IL-6, IL-17, IL-18, MMP2, MMP3 and MMP9 in patients with cerebral infarction. The serum levels of MCP-1, VE-cadherin and the contents of H-FABP, S100B, NSE, IL-1b, IL-6, IL-17, IL-18, MMP2, MMP3 and MMP9 were positively correlated. Conclusions: The serum levels of VE-cadherin and MCP-1 were significantly increased in patients with acute cerebral infarction. MCP-1 and VE-cadherin can increase the secretion of interleukins and matrix metalloproteinases, which can result in the carotid artery plaque formation, unstable plaque properties and the injury of nerve function.

  2. THE ISOLATION OF NOVEL MESENCHYMAL STROMAL CELL CHEMOTACTIC FACTORS FROM THE CONDITIONED MEDIUM OF TUMOR CELLS

    Science.gov (United States)

    Lin, Siang-Yo; Yang, Jun; Everett, Allen D.; Clevenger, Charles V.; Koneru, Mythili; Mishra, Pravin J.; Kamen, Barton; Banerjee, Debabrata; Glod, John

    2008-01-01

    Bone marrow-derived mesenchymal stromal cells (MSCs) localize to solid tumors. Defining the signaling mechanisms that regulate this process is important to understanding the role of MSCs in tumor growth. Using a combination of chromatography and electrospray tandem mass spectrometry we have identified novel soluble signaling molecules that induce MSC chemotaxis present in conditioned medium of the breast carcinoma cell line MDA-MB231. Previous work has employed survey strategies using ELISA assay to identify known chemokines that promote MSC chemotaxis. While these studies provide valuable insights into the intercellular signals that impact MSC behavior, many less well-described, but potentially important soluble signaling molecules could be overlooked using these methods. Through the less directed method of column chromatography we have identified novel candidate MSC chemotactic peptides. Two proteins, cyclophilin B and hepatoma-derived growth factor were then further characterized and shown to promote MSC chemotaxis. PMID:18722367

  3. High concentrations of circulating interleukin-6 and monocyte chemotactic protein-1 with low concentrations of interleukin-8 were associated with severe chikungunya fever during the 2009-2010 outbreak in Thailand.

    Science.gov (United States)

    Lohachanakul, Jindarat; Phuklia, Weerawat; Thannagith, Montri; Thonsakulprasert, Tipparat; Ubol, Sukathida

    2012-02-01

    The recent outbreak of Chikungunya virus in Thailand caused a rheumatic fever associated with considerable morbidity and fatalities. Thus, it is important to identify biomarker(s) of severe disease induced by this threatening arbovirus. Putative biomarkers in cases of chikungunya fever during an outbreak in the southern part of Thailand in 2009-2010 were identified. Sixty-two patients who had developed fever and myalgia, with or without arthralgia/arthritis, were enrolled and grouped into severe chikungunya fever (CHIKF) (n= 15), mild CHIKF (n= 20) and non-CHIKF (n= 27) to investigate circulating immunological mediators that might serve as markers of severity. Blood samples were taken at presentation (day 1) and 30 days later (day 30) and plasma concentrations of interleukin (IL)-1β, IL-6, IL-8, IL-17, tumor necrosis factor-alpha, monocyte chemotactic protein-1 (MCP-1), matrix metalloproteinase-1, tissue inhibitor of matrix metalloproteinase-1 and viral load were measured by ELISA. On day 1, severe CHIKF and mild CHIKF groups had viral loads of 10(8.5) and 10(8.3) of RNA copies/mL, respectively. At presentation, all CHIKF patients had circulating concentrations of IL-6 and MCP-1 higher than did non-CHIKF patients, whereas amongst the CHKF patients, the severe CHIKF patients had higher IL-6 concentrations than did mild CHIKF patients. Interestingly, severe CHIKF patients had significantly lower concentrations of circulating IL-8 than the other groups of patients, suggesting that high concentrations of IL-6 and MCP-1 with low concentrations of IL-8 may be a determinant of severe chikungunya virus infection. © 2012 The Societies and Blackwell Publishing Asia Pty Ltd.

  4. Leukocyte chemotactic factor 2 amyloidosis cannot be reliably diagnosed by immunohistochemical staining.

    Science.gov (United States)

    Paueksakon, Paisit; Fogo, Agnes B; Sethi, Sanjeev

    2014-07-01

    We investigated the role of leukocyte chemotactic factor (LECT2) immunohistochemical staining in the diagnosis of type of renal amyloidosis. Fifty renal amyloidosis cases with available paraffin blocks in our 2002 to 2012 renal biopsy files were reviewed. Patients were designated as a defined amyloid, including amyloid light chain (AL) and amyloid-associated amyloid (AA), or a non-AL/non-AA amyloid group. LECT2-specific antibody immunohistochemistry was performed in all 50 cases. Laser microdissection and mass spectrometry (LMD/MS) were performed in 10 cases. Forty-five patients had amyloid classified as either AL (44) or AA (1), and 5 had undetermined amyloid. Three of the five non-AL/non-AA group patient biopsies showed positive LECT2 immunohistochemical staining, and of these, LECT2 was also identified by LMD/MS in 1 patient, fibrinogen-α was identified in 1 patient, and apolipoprotein IV was identified in 1 patient. Two of these non-AL/non-AA patients showed negative LECT2 staining, and LMD/MS showed apolipoprotein IV as a major protein component. Five of the 44 AL amyloid patients showed weakly positive LECT2 staining. However, LECT2 was not identified by LMD/MS in any of these 5 cases. The single patient with AA amyloid was negative for LECT2 by immunohistochemical staining. Among 5 non-AL and non-AA amyloidosis patients in our study, 1 had LECT2, 1 had fibrinogen-α, and 3 had apolipoprotein IV as a major protein component. The data from this study show that weak LECT2 staining should be regarded as indeterminate or a negative result and does not per se allow diagnosis of specific amyloid type. The diagnosis of LECT2 renal amyloidosis may require LMD/MS confirmation.

  5. A new monoclonal antibody (5D3-F7) which recognizes human monocyte-chemotactic protein-1 but not related chemokines. Development of a sandwich ELISA and in situ detection of producing cells.

    Science.gov (United States)

    Peri, G; Milanese, C; Matteucci, C; Ruco, L; Zhou, D; Sozzani, S; Coletta, I; Mantovani, A

    1994-09-14

    Chemokines are a superfamily of structurally related cytokines involved in leukocyte recruitment in normal and neoplastic tissues. The availability of non-cross-reacting reagents specific for each member of the C-C and C-X-C family is important for careful characterization of their in vitro and in vivo production and relevance. Here we describe a novel, highly specific, mAb against monocyte chemotactic protein-1 (MCP-1). The 5D3-F7 mAb (IgG1,kappa) recognizes human recombinant and natural MCP-1 in ELISA, immunoprecipitation and immunoblot analysis. As a source of natural MCP-1 we used the 8387 human sarcoma line which produces spontaneously MCP-1 and responds to TNF with increased expression and release. The 5D3-F7 mAb inhibited the chemotactic activity of MCP-1 for monocytes. Using the 5D3-F7 mAb and a polyclonal rabbit anti-MCP-1 serum, a sandwich ELISA was developed. In both the direct and the sandwich ELISA, the 5D3-F7 mAb recognized human MCP-1, but not the closely related C-C chemokines MCP-1, MCP-2, MCP-3, MIP-1 alpha, and RANTES and the C-X-C chemokines IL-8, gro alpha and NAP-2. In culture supernatants the sensitivity of the sandwich ELISA was approximately equal to 30 pg/ml. The sandwich ELISA permitted detection of MCP-1 in resting or cytokine-stimulated endothelial, mesothelial and Kaposi's sarcoma cells. Preliminary immunohistochemical analysis revealed production of MCP-1 by macrophage-like cells at sites of inflammation. The 5D3-F7 mAb provides a novel, highly specific reagent with which to investigate the in vitro and in vivo production and role of MCP-1.

  6. The production of monocyte chemoattractant protein-1 (MCP-1)/CCL2 in tumor microenvironments.

    Science.gov (United States)

    Yoshimura, Teizo

    2017-02-08

    Infiltration of leukocytes is one of the hallmarks of the inflammatory response. Among the leukocyte populations, neutrophils are the first to infiltrate, followed by monocytes and lymphocytes, suggesting the presence of mediators that specifically recruit these cell types. Cytokine-like chemoattractants with monocyte chemotactic activity, such as lymphocyte-derived chemotactic factor (LDCF) or tumor-derived chemotactic factor (TDCF), were reported as molecules that could play a critical role in the recruitment of monocytes into sites of immune responses or tumors; however, their identities remained unclear. In the 1980s, researchers began to test the hypothesis that leukocyte chemotactic activity is a part of the wider activities exhibited by cytokines, such as interleukin-1 (IL-1). In 1987, we demonstrated, for the first time, the presence of a cytokine like chemoattractant with cell type-specificity (now known as the chemokine interleukin-8 or CXC chemokine ligand 8) that was different from IL-1. This led us to the purification of the second such molecule with monocyte chemotactic activity. This monocyte chemoattractant was found identical to the previously described LDCF or TDCF, and termed monocyte chemoattractant protein-1 (MCP-1). Isolation of MCP-1 created a revolution in not only inflammation but also cancer research that continues today, and MCP-1 has become a molecular target to treat patients with many diseases. In this review, I will first describe a history associated with the discovery of MCP-1 and then discuss complex mechanisms regulating MCP-1 production in tumor microenvironments.

  7. Modulation of neutrophil and monocyte function by recombinant human granulocyte macrophage colony-stimulating factor in patients with lymphoma.

    Science.gov (United States)

    Kharazmi, A; Nielsen, H; Hovgaard, D; Borregaard, N; Nissen, N I

    1991-04-01

    Granulocyte macrophage colony-stimulating factor (GM-CSF) has been shown to inhibit the chemotaxis and enhance the oxidative burst response of human neutrophils in vitro. The present study describes the effect of recombinant GM-CSF on the neutrophil and monocyte function in patients with lymphoma undergoing GM-CSF treatment. Patients with either Hodgkin's or non-Hodgkin's lymphoma were treated with various dosages (2-16 micrograms kg-1 body weight per day for 5 days) of rhGM-CSF by intravenous or subcutaneous route. Prior to and on day 5 of rhGM-CSF treatment, neutrophil and monocyte chemotaxis and chemiluminescence responses to f-Met-Leu-Phe, zymosan activated serum (ZAS) and opsonized zymosan (OZ) were determined. It was observed that chemotactic response of neutrophils to f-Met-Leu-Phe and ZAS was reduced, whereas the chemiluminescence response of both cell types to f-Met-Leu-Phe and zymosan was enhanced by up to 43-fold. rhGM-CSF treatment did not affect degranulation of the neutrophils as measured by release of vitamin B12 binding protein. Degree of modulation of neutrophil and monocyte function by rhGM-CSF was independent of rhGM-CSF dosages administered. These data suggest that phagocytic defence system may be enhanced by GM-CSF treatment and that this cytokine may be a useful therapeutic adjunct in compromised patients.

  8. Human monocyte-derived dendritic cells expressing both chemotactic cytokines IL-8, MCP-1, RANTES and their receptors,and their selective migration to these chemokines

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Objective To characterize the mRNA expression of CXC chemokine IL-8, CC chemokine monocyte chemothractant protein-1 (MCP-1) and regulated on activation,normal T cell expressed and secreted (RANTES), and a newly defined DC chemokine DC- CK1 as well as the expression of IL-8 receptor, MCP-1 receptor and RANTES receptor in human monocyte derived dendritic cells (MoDCs).The migratory responsiveness of MoDC to IL-8, MCP-1 and RANTES was alsso studied. Methods In vitro generated MoDCs were obtained by differentiating monocytes in the presence of GM-CSF and IL-4 for 5 days. The time course of RNA expression was analyzed by RT-PCR and migratoly ability was assessed by a micromultiwell chemotaxis chamber assay. Results IL-8, MCP-1, RANTES and their corres ponding receptors were consistently expressed in MoDCs. DC-CK-1 expression was detectable efter 48 hours of differentiation. MoDC selectively migrated in response to MCP-1 and RANTES but not to IL-8 though transcripts of IL-8 receptor were present. Conclusion Because the capacity of dendritic cells to initiate immune responses depends on their specialized migratory and tissue homing properties, the expression of chemokines and their receptors along with the migratory responsiveness to chemokines of MoDC in our study suggests a potential role of chemokines in the interaction between dendritic cells and T cells and the induction of immune responses.

  9. P-Selectin Induces the Expression of Tissue Factor on Monocytes

    Science.gov (United States)

    Celi, Alessandro; Pellegrini, Giuliana; Lorenzet, Roberto; de Blasi, Antonio; Ready, Neal; Ready, Neal; Furie, Barbara C.; Furie, Bruce

    1994-09-01

    P-selectin on activated platelets and stimulated endothelial cells mediates cell adhesion with monocytes and neutrophils. Since activated platelets induce tissue factor on mononuclear leukocytes, we examined the effect of P-selectin on the expression of tissue factor activity in monocytes. Purified P-selectin stimulated tissue factor expression on mononuclear leukocytes in a dose-dependent manner. Chinese hamster ovary (CHO) cells expressing P-selectin stimulated tissue factor procoagulant activity in purified monocytes, whereas untransfected CHO cells and CHO cells expressing E-selectin did not. Anti-P-selectin antibodies inhibited the effects of purified P-selectin and CHO cells expressing P-selectin on monocytes. Incubation of CHO cells expressing P-selectin with monocytes leads to the development of tissue factor mRNA in monocytes and to the expression of tissue factor antigen on the monocyte surface. These results indicate that P-selectin upregulates the expression of tissue factor on monocytes as well as mediates the binding of platelets and endothelial cells with monocytes and neutrophils. The binding of P-selectin to monocytes in the area of vascular injury may be a component of a mechanism that initiates thrombosis.

  10. Beta-adrenergic receptor agonists induce the release of granulocyte chemotactic protein-2, oncostatin M, and vascular endothelial growth factor from macrophages

    NARCIS (Netherlands)

    Verhoeckx, K.C.M.; Doornbos, R.P.; Witkamp, R.F.; Greef, de J.; Rodenburg, R.J.T.

    2006-01-01

    Vascular endothelial growth factor (VEGF), oncostatin M (OSM), and granulocyte chemotactic protein-2 (GCP-2/CXCL6) are up-regulated in U937 macrophages and peripheral blood macrophages exposed to LPS, beta-adrenergic receptor (ß2-AR) agonists (e.g. zilpaterol, and clenbuterol) and some other agents

  11. Beta-adrenergic receptor agonists induce the release of granulocyte chemotactic protein-2, oncostatin M, and vascular endothelial growth factor from macrophages

    NARCIS (Netherlands)

    Verhoeckx, K.C.; Doornbos, R.P.; Witkamp, R.F.; Greef, J. van der; Rodenburg, R.J.T.

    2006-01-01

    Vascular endothelial growth factor (VEGF), oncostatin M (OSM), and granulocyte chemotactic protein-2 (GCP-2/CXCL6) are up-regulated in U937 macrophages and peripheral blood macrophages exposed to LPS, beta-adrenergic receptor (beta2-AR) agonists (e.g. zilpaterol, and clenbuterol) and some other agen

  12. Beta-adrenergic receptor agonists induce the release of granulocyte chemotactic protein-2, oncostatin M, and vascular endothelial growth factor from macrophages

    NARCIS (Netherlands)

    Verhoeckx, K.C.M.; Doornbos, R.P.; Witkamp, R.F.; Greef, J. van der; Rodenburg, R.J.T.

    2006-01-01

    Vascular endothelial growth factor (VEGF), oncostatin M (OSM), and granulocyte chemotactic protein-2 (GCP-2/CXCL6) are up-regulated in U937 macrophages and peripheral blood macrophages exposed to LPS, beta-adrenergic receptor (β2-AR) agonists (e.g. zilpaterol, and clenbuterol) and some other agents

  13. Evidence for a novel chemotactic C1q domain-containing factor in the leech nerve cord.

    Science.gov (United States)

    Tahtouh, Muriel; Croq, Françoise; Vizioli, Jacopo; Sautiere, Pierre-Eric; Van Camp, Christelle; Salzet, Michel; Daha, Mohamed R; Pestel, Joël; Lefebvre, Christophe

    2009-02-01

    In vertebrates, central nervous system (CNS) protection is dependent on many immune cells including microglial cells. Indeed, activated microglial cells are involved in neuroinflammation mechanisms by interacting with numerous immune factors. Unlike vertebrates, some lophotrochozoan invertebrates can fully repair their CNS following injury. In the medicinal leech Hirudo medicinalis, the recruitment of microglial cells at the lesion site is essential for sprouting of injured axons. Interestingly, a new molecule homologous to vertebrate C1q was characterized in leech, named HmC1q (for H. medicinalis) and detected in neurons and glial cells. In chemotaxis assays, leech microglial cells were demonstrated to respond to human C1q. The chemotactic activity was reduced when microglia was preincubated with signaling pathway inhibitors (Pertussis Toxin or wortmannin) or anti-human gC1qR antibody suggesting the involvement of gC1qR in C1q-mediated migration in leech. Assays using cells preincubated with NO chelator (cPTIO) showed that C1q-mediated migration was associated to NO production. Of interest, by using anti-HmC1q antibodies, HmC1q released in the culture medium was shown to exhibit a similar chemotactic effect on microglial cells as human C1q. In summary, we have identified, for the first time, a molecule homologous to mammalian C1q in leech CNS. Its chemoattractant activity on microglia highlights a new investigation field leading to better understand leech CNS repair mechanisms.

  14. Δ(9)-Tetrahydrocannabinol (THC) enhances lipopolysaccharide-stimulated tissue factor in human monocytes and monocyte-derived microvesicles.

    Science.gov (United States)

    Williams, Julie C; Klein, Thomas W; Goldberger, Bruce A; Sleasman, John W; Mackman, Nigel; Goodenow, Maureen M

    2015-01-01

    Immunomodulatory effects in humans of Δ(9-)Tetrahydrocannabinol (THC), the psychoactive component of marijuana are controversial. Tissue factor (TF), the activator of the extrinsic coagulation cascade, is increased on circulating activated monocytes and is expressed on microvesicles released from activated monocytes during inflammatory conditions, which perpetuate coagulopathies in a number of diseases. In view of the increased medicinal use of marijuana, effects of THC on human monocytes and monocyte-derived microvesicles activated by lipopolysaccharide (LPS) were investigated. Peak levels of TF procoagulant activity developed in monocytes or microvesicles 6 h following LPS treatment and were unaltered by THC. After 24 h of LPS stimulation, TF activity declined in control-treated or untreated cells and microvesicles, but persisted with THC treatment. Peak TF protein occurred within 6 h of LPS treatment independent of THC; by 24 h, TF protein declined to almost undetectable levels without THC, but was about 4-fold greater with THC. Steady-state TF mRNA levels were similar up to 2 h in the presence of LPS with or without THC, while 10-fold greater TF mRNA levels persisted over 3-24 h with THC treatment. Activation of MAPK or NF-κB pathways was unaltered by THC treatment and inflammatory cytokine IL-6 levels were unchanged. In contrast, TNF and IL-8 levels were enhanced by 20-50 %. THC enhances TF expression in activated monocytes resulting in elevated procoagulant activity. Marijuana use could potentiate coagulopathies in individuals with chronic immune activation such as HIV-1 infection or inflammatory bowel disease.

  15. Tumour necrosis factor and eicosanoid production from monocytes exposed to HIV in vitro

    DEFF Research Database (Denmark)

    Skøt, J; Kabrit, P; Hansen, J E;

    1994-01-01

    We investigated the hypothesis that exposure of monocytes to human immunodeficiency virus (HIV) augments production of proinflammatory mediators. The production of tumour necrosis factor alpha (TNF-alpha) and the eicosanoids PGE2 and LTB4 from human monocytes was evaluated after exposure to two...

  16. An enzyme immunoassay for detection of Japanese encephalitis virus-induced chemotactic cytokine

    Indian Academy of Sciences (India)

    Aditi Singh; Rajesh Kulshreshtha; Asha Mathur

    2000-03-01

    Japanese encephalitis virus (JEV) induces human peripheral blood monocytes to secrete a chemotactic cytokine [human macrophage-derived factor (hMDF)] which causes chemotaxis of neutrophils. The only known assay for hMDF cannot quantify its level in samples, so an enzyme immunoassay has been standardized for detection of hMDF and hMDF-specific antibodies in test samples. The reported enzyme linked immunosorbent assay (ELISA) was found to be sensitive (89%), specific (91%), accurate (92·2%) and reproducible and was able to detect a minimum concentration of 23 ng hMDF/ml in test samples. The chemotactic factor could be detected in JEV inoculated mouse sera and JEV infected culture fluids. Significant finding of the test was the detection of hMDF in sera of human cases of JE.

  17. Different effect induced by treatment with several statins on monocyte tissue factor expression in hypercholesterolemic subjects.

    Science.gov (United States)

    Bruni, F; Puccetti, L; Pasqui, A L; Pastorelli, M; Bova, G; Cercignani, M; Palazzuoli, A; Leo, A; Auteri, A

    2003-05-01

    Platelets and monocytes are involved in atherothrombosis via tissue factor expression. Moreover, they are activated in hypercholesterolemia, a classic risk factor for atherothrombosis. Cholesterol-lowering drugs (statins) reduce cardiovascular risk either by decreasing cholesterol or non-lipidic actions, such as platelet and monocyte activity. The aim of our study was to evaluate the effect of several statins on platelet and monocyte activity in hypercholesterolemic subjects. Platelet activity (P-selectin, cytofluorimetric detection), tissue factor levels (ELISA) and activity (detected in whole blood and cellular preparations by a specific clotting assay) were measured in hypercholesterolemic subjects (41 males, 23 females, aged 34-65 years, total cholesterol 6.86+/-0.60 mmol/l) treated with atorvastatin 10 mg, simvastatin 20 mg, fluvastatin 40 mg, or pravastatin 40 mg for 6 weeks. P-selectin and tissue factor expression in whole blood and isolated cells were increased in hypercholesterolemic subjects with respect to controls (all Psel and cholesterol (Pimpact of several statins on monocyte tissue factor expression in whole blood, suggesting a possible role of decreased platelet activity and a direct action on monocytes. In contrast, pravastatin decreased monocyte procoagulant activity with relation to cholesteroldependent modifications of platelet function.

  18. Monocyte-mediated tumoricidal activity via the tumor necrosis factor-related cytokine, TRAIL.

    Science.gov (United States)

    Griffith, T S; Wiley, S R; Kubin, M Z; Sedger, L M; Maliszewski, C R; Fanger, N A

    1999-04-19

    TRAIL (tumor necrosis factor [TNF]-related apoptosis-inducing ligand) is a molecule that displays potent antitumor activity against selected targets. The results presented here demonstrate that human monocytes rapidly express TRAIL, but not Fas ligand or TNF, after activation with interferon (IFN)-gamma or -alpha and acquire the ability to kill tumor cells. Monocyte-mediated tumor cell apoptosis was TRAIL specific, as it could be inhibited with soluble TRAIL receptor. Moreover, IFN stimulation caused a concomitant loss of TRAIL receptor 2 expression, which coincides with monocyte acquisition of resistance to TRAIL-mediated apoptosis. These results define a novel mechanism of monocyte-induced cell cytotoxicity that requires TRAIL, and suggest that TRAIL is a key effector molecule in antitumor activity in vivo.

  19. Monocyte functions in diabetes mellitus.

    Science.gov (United States)

    Geisler, C; Almdal, T; Bennedsen, J; Rhodes, J M; Kølendorf, K

    1982-02-01

    The aim of this study was to investigate the functions of monocytes obtained from 14 patients with diabetes mellitus (DM) compared with those of monocytes from healthy individuals. It was found that the total number of circulating monocytes in the 14 diabetic patients was lower than that from the healthy individuals. Phagocytosis of Candida albicans was decreased in the monocytes from the patients, whereas pinocytosis of acridine and phagocytosis of latex and sheep red blood cells were normal. The chemotactic response towards casein was enhanced. The possible consequences of these findings for the elucidation of concomitant infections in diabetic patients are discussed.

  20. High-fat diet enhances and monocyte chemoattractant protein-1 deficiency reduces bone loss in mice with pulmonary metastases of Lewis lung carcinoma

    Science.gov (United States)

    Bone is adversely affected by metastasis and metastasis-associated complications. Obesity is a risk factor for both bone and cancer. Adipose tissue is an endocrine organ that produces pro-inflammatory adipokines, such as monocyte chemotactic protein-1 (MCP-1), that contribute to obesity and obesit...

  1. Poly(ethylene glycol)-containing hydrogels modulate α-defensin release from polymorphonuclear leukocytes and monocyte recruitment.

    Science.gov (United States)

    Lieberthal, Tyler Jacob; Cohen, Hannah Caitlin; Kao, W John

    2015-12-01

    Polymorphonuclear leukocytes (PMNs) release granule proteins as the first line of defense against bacteria and set up chemotactic gradients that result in monocyte infiltration to the site of injury. Although well established, the role of biomaterials in regulating adherent PMN degranulation and subsequent PMN-monocyte paracrine interactions is less clear. The aim of this study was to determine how biomaterials affect the degranulation of selected biomarkers and downstream monocyte adhesion and transendothelial migration. Poly(ethylene glycol) (PEG)-containing hydrogels (PEG and an interpenetrating network of PEG and gelatin) promote the release of the α-defensins human neutrophil peptides 1-3, but not azurocidin or monocyte chemotactic protein-1. Although human neutrophil peptides 1-3 are monocyte chemoattractants, no subsequent effects on monocyte transmigration are observed in static conditions. Under flow conditions, monocyte adhesion on human umbilical vein endothelial cells stimulated with tumor necrosis factor-α is elevated in the presence of granule proteins from PMNs adherent on polydimethylsiloxane, but not from PMNs cultured on PEG hydrogels. These results suggest that PEG promotes PMN antimicrobial capacity without enhanced monocyte recruitment.

  2. Stromal-derived factor-1α/CXCL12-CXCR4 chemotactic pathway promotes perineural invasion in pancreatic cancer.

    Science.gov (United States)

    Xu, Qinhong; Wang, Zheng; Chen, Xin; Duan, Wanxing; Lei, Jianjun; Zong, Liang; Li, Xuqi; Sheng, Liang; Ma, Jiguang; Han, Liang; Li, Wei; Zhang, Lun; Guo, Kun; Ma, Zhenhua; Wu, Zheng; Wu, Erxi; Ma, Qingyong

    2015-03-10

    Perineural invasion (PNI) is considered as an alternative route for the metastatic spread of pancreatic cancer cells; however, the molecular changes leading to PNI are still poorly understood. In this study, we show that the CXCL12/CXCR4 axis plays a pivotal role in the neurotropism of pancreatic cancer cells to local peripheral nerves. Immunohistochemical staining results revealed that CXCR4 elevation correlated with PNI in 78 pancreatic cancer samples. Both in vitro and in vivo PNI models were applied to investigate the function of the CXCL12/CXCR4 signaling in PNI progression and pathogenesis. The results showed that the activation of the CXCL12/CXCR4 axis significantly increased pancreatic cancer cells invasion and promoted the outgrowth of the dorsal root ganglia. CXCL12 derived from the peripheral nerves stimulated the invasion and chemotactic migration of CXCR4-positive cancer cells in a paracrine manner, eventually leading to PNI. In vivo analyses revealed that the abrogation of the activated signaling inhibited tumor growth and invasion of the sciatic nerve toward the spinal cord. These data indicate that the CXCL12/CXCR4 axis may be a novel therapeutic target to prevent the perineural dissemination of pancreatic cancer.

  3. In vitro production of tumor necrosis factor-alpha by human monocytes stimulated with lipopolysaccharide is positively correlated with increased blood monocytes after exposure to a swine barn.

    Science.gov (United States)

    Willson, P J; Khozani, T Talaei; Juurlink, B H J; Senthilselvan, A; Rennie, D C; Gerdts, V; Gawaziuk, J; Schneberger, D; Burch, Lauranell H; Dosman, J A

    2008-01-01

    Recently there has been interest in the air quality in and around intensive livestock production facilities, such as modern swine production barns, where agricultural workers and surrounding residents may be exposed to elevated levels of organic dusts. The health effects of these exposures are not completely understood. The study that is reported here is a component of a larger investigation of the relationships among the acute effects of high-concentration endotoxin exposure (swine barn dust), polymorphisms in the TLR4 gene, and respiratory outcomes following exposure to swine confinement buildings. The relationships among a mediator of acute lung inflammation, tumor necrosis factor alpha (TNF-alpha), and clinical responses to acute swine barn exposure were characterized. Analysis of the results showed that in vitro stimulation of human monocytes with as little as 1 ng/ml of lipopolysaccharide (LPS) produced a significant increase in the monocytes that produced TNF-alpha. Although the proportion of TNF-alpha-positive monocytes after in vitro stimulation with 1 ng/ml of LPS was not associated with gender or TLR4 genotype, it was positively associated with the concentration of monocytes in blood after barn exposure. Thus, these two responses to different forms of LPS exposure are significantly correlated, and more responsive monocytes in vitro indicate a forthcoming relative monocytosis, post barn exposure, which may initiate a cascade of chronic inflammation.

  4. Chemotactic Maneuverability of Sperm

    CERN Document Server

    Guasto, Jeffrey S; Zimmer, Richard K; Stocker, Roman

    2011-01-01

    In this fluid mechanics video, we explore the kinematics of chemotaxing sperm cells (sea urchin, \\textit{Arbacia punctulata}) swimming in a chemoattractant gradient. We demonstrate that the complex swimming trajectories resulting in chemotactic behavior (`turn-and-run' motility) are comprised of several distinct flagellar maneuvers. These motility patterns likely play an important role optimizing chemotaxic motility and navigation, when the sperm cells are subjected external fluid flows.

  5. Blood platelet and monocyte activations and relation to stages of liver cirrhosis

    Institute of Scientific and Technical Information of China (English)

    Anatol Panasiuk; Janusz Zak; Edwina Kasprzycka; Katarzyna Janicka; Danuta Prokopowicz

    2005-01-01

    AIM: Blood platelets (plt) and monocytes are the cells that play a crucial role in the pathogenesis of liver damage and liver cirrhosis (LC). In this paper, the analysis of mutual relationship between platelets and monocytes activation in LC was conducted.METHODS: Immunofluorescent flow cytometry was usedto measure the percentage of activated platelet populations(CD62P, CD63), the percentage of plt-monocyte aggregates (pma) (CD41/CD45), and activated monocytes (CD11b, CD14, CD16) in the blood of 20 volunteers and 40 patientswith LC. Platelet activation markers: sP-selectin, platelet factor 4 (PF4), beta-thromboglobulin (βTG) and monocyte chemotactic peptide-1 (MCP-1) were measured and compared in different stages of LC.RESULTS: Platelet activation with the increase in bothβTG serum concentration and elevation of plt population(CD62P and CD63 as well as MIF CD62P and CD63) is elevated as LC develops and thrombocytopenia rises. There is a positive correlation between medial intensityof fluorescence (MIF) CD62P and MIF CD63 in LC. We did not show any relationship between monocyte activation and pma level. SP-selectin concentration correlates positively with plt count and pma, and negatively with stage of plt activation and MIF CD62P and MIF CD63. There was no correlation between MCP-1 concentration andpit, monocyte activation as well as pma level in LC. CD16 monocytes and MIF CD16 populations are significantlyhigher in the end stage of LC. A positive correlation occurs between the value of CD11b monocyte population andMIF CD14 and MIF CD16 on monocytes in LC.CONCLUSION: Platelet and monocyte activation plays an important role in LC. Platelet activation stage does not influence monocyte activation and production of plt aggregates with monocytes in LC. With LC development, thrombocytopenia may be the result of plt consumption in platelet-monocyte aggregates.

  6. Unfractionated heparin suppresses lipopolysaccharide-induced monocyte chemoattractant protein-1 expression in human microvascular endothelial cells by blocking Krüppel-like factor 5 and nuclear factor-κB pathway.

    Science.gov (United States)

    Li, Xu; Li, Xin; Zheng, Zhen; Liu, Yina; Ma, Xiaochun

    2014-10-01

    Unfractionated heparin (UFH) and low-molecular-weight heparins (LMWH), apart from anticoagulant activities, contain a variety of biological properties such as anti-inflammatory actions possibly affecting sepsis. Chemokines are vital for promoting the movement of circulating leukocytes to the site of infection and are involved in the pathogenesis of sepsis. The purpose of this study was to investigate the effects and potential mechanisms of UFH on lipopolysaccharide (LPS)-induced chemokine production in human pulmonary microvascular endothelial cells (HPMECs). HPMECs were pretreated with UFH (0.1 U/ml and 1 U/ml), 15 min prior to stimulation with LPS (10 μg/ml). Cells were cultured under various experimental conditions for 2 h and 6 h for analysis. UFH markedly decreased LPS-induced interleukin (IL)-8 and monocyte chemoattractant protein-1 (MCP-1) mRNA and protein expression in HPMECs. UFH also attenuated the secretion of these chemokines in culture supernatants. In addition, UFH blocked the chemotactic activities of LPS-stimulated HPMECs supernatants on monocytes migration as expected. UFH inhibited LPS-induced Krüppel-like factor 5 (KLF-5) mRNA and protein levels. Concurrently, UFH reduced nuclear factor (NF)-κB nuclear translocation. Importantly, transfection with siRNA targeting KLF-5 reduced NF-κB activation and chemokines expression. These results demonstrate that interfering with KLF-5 mediated NF-κB activation might contribute to the inhibitory effects of chemokines and monocytes migration by UFH in LPS-stimulated HPMECs.

  7. Platelet-derived stromal cell-derived factor-1 is required for the transformation of circulating monocytes into multipotential cells.

    Directory of Open Access Journals (Sweden)

    Noriyuki Seta

    Full Text Available BACKGROUND: We previously described a primitive cell population derived from human circulating CD14(+ monocytes, named monocyte-derived multipotential cells (MOMCs, which are capable of differentiating into mesenchymal and endothelial lineages. To generate MOMCs in vitro, monocytes are required to bind to fibronectin and be exposed to soluble factor(s derived from circulating CD14(- cells. The present study was conducted to identify factors that induce MOMC differentiation. METHODS: We cultured CD14(+ monocytes on fibronectin in the presence or absence of platelets, CD14(- peripheral blood mononuclear cells, platelet-conditioned medium, or candidate MOMC differentiation factors. The transformation of monocytes into MOMCs was assessed by the presence of spindle-shaped adherent cells, CD34 expression, and the potential to differentiate in vitro into mesenchymal and endothelial lineages. RESULTS: The presence of platelets or platelet-conditioned medium was required to generate MOMCs from monocytes. A screening of candidate platelet-derived soluble factors identified stromal cell-derived factor (SDF-1 as a requirement for generating MOMCs. Blocking an interaction between SDF-1 and its receptor CXCR4 inhibited MOMC generation, further confirming SDF-1's critical role in this process. Finally, circulating MOMC precursors were found to reside in the CD14(+CXCR4(high cell population. CONCLUSION: The interaction of SDF-1 with CXCR4 is essential for the transformation of circulating monocytes into MOMCs.

  8. Tissue factor expression on the surface of monocytes from a patient with hereditary angioedema.

    Science.gov (United States)

    Iwamoto, Kazumasa; Morioke, Satoshi; Yanase, Yuhki; Uchida, Kazue; Hide, Michihiro

    2014-10-01

    Hereditary angioedema (HAE) presents as severe angioedema, which is mostly due to the C1 inhibitor (C1-INH) gene mutations. Environmental factors, minor trauma and oral contraceptives have been reported to induce angioedema attack, but the trigger may often be uncertain. Activated factor XII controlled by C1-INH facilitates bradykinin generation and also regulates coagulation cascade, but the relationship between edema formation and coagulation is still unclear. We have described a 35-year-old female patient with HAE, presenting with frequent angioedema attacks in the absence of an apparent triggering factor. She showed higher levels of FDP and D-dimer during angioedema than those in remission. In addition, tissue factor (TF), an initiator of the extrinsic coagulation cascade, was expressed on the surface of monocytes. It was significantly higher than that of monocytes from healthy controls and tends to further increase during attacks. The expression of TF on monocytes may play a role in the induction of angioedema attacks in HAE by activating the coagulation pathway in association with reduced functions of C1-INH.

  9. Interaction between human monocytes and vascular smooth muscle cells induces vascular endothelial growth factor expression.

    Science.gov (United States)

    Hojo, Y; Ikeda, U; Maeda, Y; Takahashi, M; Takizawa, T; Okada, M; Funayama, H; Shimada, K

    2000-05-01

    The objective of this study was to investigate whether synthesis of vascular endothelial growth factor (VEGF), a major mitogen for vascular endothelial cells, was induced by a cell-to-cell interaction between monocytes and vascular smooth muscle cells (VSMCs). Human VSMCs and THP-1 cells (human monocytoid cell) were cocultured. VEGF levels in the coculture medium were determined by enzyme-linked immunosorbent assay. Northern blot analysis of VEGF mRNA was performed using a specific cDNA probe. Immunohistochemistry was performed to determine which types of cell produce VEGF. Adding THP-1 cells to VSMCs for 24 h increased VEGF levels of the culture media, 8- and 10-fold relative to those of THP-1 cells and VSMCs alone, respectively. Northern blot analysis showed that VEGF mRNA expression was induced in the cocultured cells and peaked after 12 h. Immunohistochemistry disclosed that both types of cell in the coculture produced VEGF. Separate coculture experiments revealed that both direct contact and a soluble factor(s) contributed to VEGF production. Neutralizing anti-interleukin (IL)-6 antibody inhibited VEGF production by the coculture of THP-1 cells and VSMCs. A cell-to-cell interaction between monocytes and VSMCs induced VEGF synthesis in both types of cell. An IL-6 mediated mechanism is at least partially involved in VEGF production by the cocultures. Local VEGF production induced by a monocyte-VSMC interaction may play an important role in atherosclerosis and vascular remodeling.

  10. Tumour necrosis factor and eicosanoid production from monocytes exposed to HIV in vitro

    DEFF Research Database (Denmark)

    Skøt, J; Kabrit, P; Hansen, J E

    1994-01-01

    We investigated the hypothesis that exposure of monocytes to human immunodeficiency virus (HIV) augments production of proinflammatory mediators. The production of tumour necrosis factor alpha (TNF-alpha) and the eicosanoids PGE2 and LTB4 from human monocytes was evaluated after exposure to two...... strains of HIV (SSI-002 or HIV-1IIIB). After 16 h incubation with low doses of SSI-002, lipopolysaccharide-stimulated TNF-alpha production was enhanced 70-85% while PGE2 production was decreased. Heat-inactivated virus failed to alter the production of these mediators. Higher viral doses tended...... to decrease TNF-alpha and PGE2 production concomitantly, but this might be due to toxicity. HIV-1IIIB had no effect on either TNF-alpha or PGE2 production. Calcium ionophore-stimulated LTB4 production was doubled by HIV-1IIIB, but significantly decreased by SSI-002. Three or seven days after exposure to both...

  11. Effects of transforming growth factor-beta on long-term human cord blood monocyte cultures

    Energy Technology Data Exchange (ETDEWEB)

    Orcel, P.; Bielakoff, J.; De Vernejoul, M.C. (INSERM U18, Hopital Lariboisiere, Paris (France))

    1990-02-01

    Transforming growth factor-beta (TGF-beta) modulates growth and differentiation in many cell types and is abundant in bone matrix. We recently showed that human cord blood monocytes cultured in the presence of 1,25(OH)2D3 acquire some features of osteoclast precursors. Since TGF-beta has been shown to influence bone resorption in organ culture, we have studied the effect of TGF-beta (1-1,000 pg/ml) on cord blood monocyte cultures. These cells were cultured on plastic substrate during 3 weeks in the presence of 20% horse serum and 10(-9) M 1,25(OH)2D3. TGF-beta, from a concentration of 10 pg/ml in the culture medium, decreased in a dose dependent manner the formation of multinucleated cells. At a concentration of TGF-beta of 1 ng/ml, the multinucleated cells were reduced to 2.1% +/- 0.3%, compared to 19.3% +/- 1.5% in control cultures. TGF-beta inhibited in a dose-dependent manner the proliferation of cord blood monocytes as assessed by 3H-thymidine incorporation at 7 and 14 days of culture. The fusion index was also decreased by 3 weeks of treatment with TGF-beta. Indomethacin did not reverse the inhibitory effects of TGF-beta. The expression of the osteoclastic phenotype was assessed using two different antibodies: 23C6, a monoclonal antibody directed against the vitronectin receptor, which is highly expressed by osteoclasts but not by adult monocytes, and an antibody to HLA-DR, which is not present on osteoclast. TGF-beta decreased the expression of HLA-DR and increased in a dose-dependent manner the proportion of 23C6-labeled cells; these results suggest that TGF-beta could modulate a differentiation effect to the osteoclastic phenotype. However, when cord blood monocytes were cultured on devitalized rat calvariae prelabeled with 45Ca, TGF-beta did not induce any 45Ca release from bone cultured with monocytes.

  12. Differential procoagulant activity of microparticles derived from monocytes, granulocytes, platelets and endothelial cells: impact of active tissue factor.

    Science.gov (United States)

    Shustova, Olga N; Antonova, Olga A; Golubeva, Nina V; Khaspekova, Svetlana G; Yakushkin, Vladimir V; Aksuk, Svetlana A; Alchinova, Irina B; Karganov, Mikhail Y; Mazurov, Alexey V

    2016-12-06

    Microparticles released by activated/apoptotic cells exhibit coagulation activity as they express phosphatidylserine and some of them - tissue factor. We compared procoagulant properties of microparticles from monocytes, granulocytes, platelets and endothelial cells and assessed the impact of tissue factor in observed differences. Microparticles were sedimented (20 000g, 30 min) from the supernatants of activated monocytes, monocytic THP-1 cells, granulocytes, platelets and endothelial cells. Coagulation activity of microparticles was examined using plasma recalcification assay. The size of microparticles was evaluated by dynamic light scattering. Tissue factor activity was measured by its ability to activate factor X. All microparticles significantly accelerated plasma coagulation with the shortest lag times for microparticles derived from monocytes, intermediate - for microparticles from THP-1 cells and endothelial cells, and the longest - for microparticles from granulocytes and platelets. Average diameters of microparticles ranged within 400-600 nm. The largest microparticles were produced by endothelial cells and granulocytes, smaller - by monocytes, and the smallest - by THP-1 cells and platelets. The highest tissue factor activity was detected in microparticles from monocytes, lower activity - in microparticles from endothelial cells and THP-1 cells, and no activity - in microparticles from platelets and granulocytes. Anti-tissue factor antibodies extended coagulation lag times for microparticles from monocytes, endothelial cells and THP-1 cells and equalized them with those for microparticles from platelets and granulocytes. Higher coagulation activity of microparticles from monocytes, THP-1 cells and endothelial cells in comparison with microparticles from platelets and granulocytes is determined mainly by the presence of active tissue factor.

  13. Maturation of human dendritic cells by monocyte-conditioned medium is dependent upon trace amounts of lipopolysaccharide inducing tumour necrosis factor alpha

    DEFF Research Database (Denmark)

    Nersting, Jacob; Svenson, Morten; Andersen, Vagn

    2003-01-01

    We investigated the ability of monocyte-conditioned medium (MCM), generated by monocytes cultured on plastic-immobilised immunoglobulin, to stimulate maturation of human monocyte-derived dendritic cells (DC). Earlier reports suggest that MCM is a strong inducer of irreversible DC maturation......-stimulatory potency of LPS. Maturation by this procedure is mediated mainly by tumour necrosis factor alpha secreted from monocytes during the medium-conditioning period....

  14. EFFECTS OF SECRETABLE PLACENTAL FACTORS UPON SECRETION OF CYTOKINES BY THP-1 MONOCYTE-LIKE CELLS

    Directory of Open Access Journals (Sweden)

    Ya. S. Onokhina

    2013-01-01

    Full Text Available Abstract. Мonocytes in feto-placental circulation are exposed to factors secreted by placental tissue. These factors influence monocyte functions in pregnancy. In present study, an in vitro model (monocyte-like THP-1 cells was used for assessing effects of soluble placental factors obtained from women with physiological pregnancies, or preeclampsia cases. The following effects of placental factors were revealed: increased secretion of VEGF by THP-1 cells along with decreased secretion of IL-6, IL-8 and MCP-1 under the influence of placental factors from the I. trimester of pregnancy in comparison with III. trimester. Secretion of IL-6 and MCP-1 by THP-1 cells was increased, and secretion of soluble TNFRII was decreased upon co-cultivation with soluble placental factors from the women with preeclampsia, as compared with placental products from physiological pregnancies.The work is supported by grants ГК № 02.740.11.0711 from Ministry of Education and Science, and НШ-3594.2010.7 grant from the President of Russian Federation.

  15. Dilazep and dipyridamole inhibit tissue factor expression on monocytes induced by IgG from patients with antiphospholipid syndrome

    Institute of Scientific and Technical Information of China (English)

    Hong ZHON

    2004-01-01

    AIM: To investigate whether antiplatelet agents, dilazep and dipyridamole, inhibit tissue factor (TF) expression on monocytes induced by IgG from patients with antiphospholipid syndrome (APS). METHODS: Freshly isolated peripheral blood monocytes were allowed to adhere on plastic and then cultured in media containing patient or control antibodies and/or other agonists with or without dilazep or dipyridamole. The TF activity on monocytes was investigated by measuring factor VIIa-dependent generation of factor Xa, using a chromogenic substrate and the TF mRNA expression was examined by real-time PCR (TaqMan PCR). RESULTS: The TF activity on monocytes induced by APS IgG (250 mg/L) was inhibited by dilazep (0.15-150 μmol/L) and dipyridamole (0.2-200 μrmol/L) in a dose-dependent fashion. But, the TF mRNA expression induced by APS IgG was not inhibited. Theophylline (500 μmol/L), an adenosine receptor antagonist, could counteract the inhibitory effect of dilazep and dipyridamole on TF activity. CONCLUSION: Antiplatelet agents, dilazep and dipyridamole, block APS IgG-induced monocytes TF expression at a post-transcriptional level, partly by adenosine receptor pathway. Pharmacological agents that block monocytes TF activity, such as dilazep and dipyridamole, are a novel therapeutic approach in APS.

  16. Factor H Binds to Extracellular DNA Traps Released from Human Blood Monocytes in Response to Candida albicans

    Science.gov (United States)

    Halder, Luke D.; Abdelfatah, Mahmoud A.; Jo, Emeraldo A. H.; Jacobsen, Ilse D.; Westermann, Martin; Beyersdorf, Niklas; Lorkowski, Stefan; Zipfel, Peter F.; Skerka, Christine

    2017-01-01

    Upon systemic infection with human pathogenic yeast Candida albicans (C. albicans), human monocytes and polymorph nuclear neutrophilic granulocytes are the first immune cells to respond and come into contact with C. albicans. Monocytes exert immediate candidacidal activity and inhibit germination, mediate phagocytosis, and kill fungal cells. Here, we show that human monocytes spontaneously respond to C. albicans cells via phagocytosis, decondensation of nuclear DNA, and release of this decondensed DNA in the form of extracellular traps (called monocytic extracellular traps: MoETs). Both subtypes of monocytes (CD14++CD16−/CD14+CD16+) formed MoETs within the first hours upon contact with C. albicans. MoETs were characterized by the presence of citrullinated histone, myeloperoxidase, lactoferrin, and elastase. MoETs were also formed in response to Staphylococcus aureus and Escherichia coli, indicating a general reaction of monocytes to infectious microbes. MoET induction differs from extracellular trap formation in macrophages as MoETs are not triggered by simvastatin, an inhibitor of cholesterol synthesis and inducer of extracellular traps in macrophages. Extracellular traps from both monocytes and neutrophils activate complement and C3b is deposited. However, factor H (FH) binds via C3b to the extracellular DNA, mediates cofactor activity, and inhibits the induction of the inflammatory cytokine interleukin-1 beta in monocytes. Altogether, the results show that human monocytes release extracellular DNA traps in response to C. albicans and that these traps finally bind FH via C3b to presumably support clearance without further inflammation. PMID:28133459

  17. Inhibitory effect of esculentoside A on tumour necrosis factor α production by human monocytes

    Directory of Open Access Journals (Sweden)

    H-B. Wang

    1996-01-01

    Full Text Available Esculentoside A (EsA is a saponin isolated from the roots of Phytolacca esculenta. Previous experiments have shown that it has strong anti-inflammatory effects. Tumour necrosis factor (TNF is a very important inflammatory mediator. It is known that there are two types of TNF—TNFα is from macrophages/monocytes and TNFβ is from activated lymphocytes. In order to study the mechanism of the anti-inflammatory effect of EsA, it was determined whether TNFα production from human peripheral monocytes was altered by EsA under lipopolysaccharide (LPS-stimulated conditions. EsA was found to decrease TNFα production in a dose-dependent manner at concentrations higher than 1 μmol/l EsA. Recent studies have shown that EsA has a curative effect on chocolate cyst and other inflammatory diseases. Our previous studies have shown that EsA could reduce the release of platelet activating factor (PAF from rat macrophages, and inhibit interleukin-1 and interleukin-6 production from routine macrophages. The reducing effects of EsA on the release of TNFα, IL-1, IL-6 and PAF may explain its anti-inflammatory effect.

  18. Induction of Monocyte Chemoattractant Proteins in Macrophages via the Production of Granulocyte-macrophage Colony Stimulating Factor by Breast Cancer Cells

    Directory of Open Access Journals (Sweden)

    Teizo eYoshimura

    2016-01-01

    Full Text Available Monocyte chemoattractant protein-1 (MCP-1/CCL2 plays an important role in the initiation and progression of cancer. We previously reported that in 4T1 murine breast cancer, non-tumor stromal cells, including macrophages, were the major source of MCP-1. In the present study, we analyzed the potential mechanisms by which MCP-1 is upregulated in macrophages infiltrating 4T1 tumors. We found that cell-free culture supernatants of 4T1 cells (4T1-sup markedly upregulated MCP-1 production by peritoneal inflammatory macrophages. 4T1-sup also upregulated other MCPs, such as MCP-3/CCL7 and MCP-5/CCL12, but modestly neutrophil chemotactic chemokines, such as KC/CXCL1 or MIP-2/CXCL2. Physicochemical analysis indicated that an approximately 2 to 3 kDa 4T1 cell product was responsible for the capacity of 4T1-sup to upregulate MCP-1 expression by macrophages. A neutralizing antibody against granulocyte-macrophage-colony stimulating factor (GM-CSF, but not macrophage-colony stimulating factor, almost completely abrogated MCP-1-inducing activity of 4T1-sup, and recombinant GM-CSF potently up-regulated MCP-1 production by macrophages. The expression levels of GM-CSF in 4T1 tumors in vivo were higher than other tumors, such as Lewis lung carcinoma. Treatment of mice with anti-GM-CSF antibody significantly reduced the growth of 4T1 tumors at the injection sites but did not reduce MCP-1 production or lung metastasis in tumor-bearing mice. These results indicate that 4T1 cells have the capacity to directly up-regulate MCP-1 production by macrophages by releasing GM-CSF; however, other mechanisms are also involved in increased MCP-1 levels in the 4T1 tumor microenvironment.

  19. Interaction of vascular smooth muscle cells and monocytes by soluble factors synergistically enhances IL-6 and MCP-1 production.

    Science.gov (United States)

    Chen, Li; Frister, Adrian; Wang, Song; Ludwig, Andreas; Behr, Hagen; Pippig, Susanna; Li, Beibei; Simm, Andreas; Hofmann, Britt; Pilowski, Claudia; Koch, Susanne; Buerke, Michael; Rose-John, Stefan; Werdan, Karl; Loppnow, Harald

    2009-04-01

    Inflammatory mechanisms contribute to atherogenesis. Monocyte chemoattractant protein (MCP)-1 and IL-6 are potent mediators of inflammation. Both contribute to early atherogenesis by luring monocytes and regulating cell functions in the vessel wall. MCP-1 and IL-6 production resulting from the interaction of invading monocytes with local vessel wall cells may accelerate atherosclerosis. We investigated the influence of the interaction of human vascular smooth muscle cells (SMCs) with human mononuclear cells (MNCs) or monocytes on IL-6 and MCP-1 production in a coculture model. Interaction synergistically enhanced IL-6 and MCP-1 production (up to 30- and 10-fold, respectively) compared with separately cultured cells. This enhancement was mediated by CD14-positive monocytes. It was dependent on the SMC-to-MNC/monocyte ratio, and as few as 0.2 monocytes/SMC induced the synergism. Synergistic IL-6 production was observed at the protein, mRNA, and functional level. It was mediated by soluble factors, and simultaneous inhibition of IL-1, TNF-alpha, and IL-6 completely blocked the synergism. IL-1, TNF-alpha, and IL-6 were present in the cultures. Blockade of the synergism by soluble glycoprotein 130Fc/soluble IL-6 receptor, as well as the induction of synergistic IL-6 production by costimulation of SMCs with IL-1, TNF-alpha, and hyper-IL-6, suggested the involvement of IL-6 trans-signaling. The contribution of IL-6 was consistent with enhanced STAT3 phosphorylation. The present data suggest that SMC/monocyte interactions may augment the proinflammatory status in the tissue, contributing to the acceleration of early atherogenesis.

  20. Aberrant Low Expression of A20 in Tumor Necrosis Factor-α-stimulated SLE Monocytes Mediates Sustained NF-κB Inflammatory Response.

    Science.gov (United States)

    Shi, Xiaowei; Qian, Tian; Li, Min; Chen, Fangru; Chen, Yan; Hao, Fei

    2015-01-01

    The aberrantly activated monocytes and nuclear factor-kappaB (NF-κB) pathway contribute to the pathogenesis of systemic lupus erythematosus (SLE), and the aberrantly activated NF-κB is associated with defects in the anti-inflammatory A20 in SLE. However, whether SLE monocytes express A20 and whether the A20 expression under sustained proinflammatory stimulation is altered to contribute to the uncontrolled NF-κB inflammatory response are unclear. In this study, we found that the freshly isolated monocytes from SLE patients and healthy controls did not differ in expression levels of IL-1β, IκBα and A20. After TNF-α stimulation for 48 h, the monocytes from both groups expressed higher levels of IL-1β and IκBα than the monocytes without TNF-α treatment. Although the increased levels of NF-κB were observed in the nucleus of both the SLE and control monocytes after 24 h of TNF-α stimulation, the enhancement in SLE monocytes was significantly more robust than in the control monocytes. In addition, while the p-IκBα level in healthy monocytes was increased, the p-IκBα level in SLE monocytes was slightly decreased after TNF-α stimulation. Interestingly, after TNF-α treatment, the A20 expression in SLE monocytes was not markedly altered compared with the untreated SLE monocytes; moreover, the SLE monocytes expressed significantly lower A20 than healthy monocytes with TNF-α treatment at each time point. Results in this study demonstrate that TNF-α activates a significant NF-κB inflammatory response in SLE monocytes, which is at least partially mediated by the aberrantly low expression of A20 upon TNF-α stimulation, contributing to the prolonged inflammatory response in SLE.

  1. MCP-1 (Monocyte Chemotactic Protein-1)-induced Protein, a Recently Identified Zinc Finger Protein, Induces Adipogenesis in 3T3-L1 Pre-adipocytes without Peroxisome Proliferator-activated Receptor γ*

    OpenAIRE

    Younce, Craig W; Azfer, Asim; Kolattukudy, Pappachan E.

    2009-01-01

    Adipogenesis is a key differentiation process relevant to obesity and associated diseases such as type 2 diabetes. This process involves temporally regulated genes controlled by a set of transcription factors, CCAAT/enhancer-binding proteins (C/EBP) β, C/EBPδ, and C/EBPα and peroxisome proliferator-activated receptor γ (PPARγ). Currently, PPARγ is universally accepted as the master regulator that is necessary and sufficient to induce adipogenesis as no known factor can induce adipogenesis wit...

  2. Psoriasin: a novel chemotactic protein

    DEFF Research Database (Denmark)

    Jinquan, T; Vorum, H; Larsen, C G;

    1996-01-01

    calcium-binding protein (psoriasin, molecular mass 11,457 Da, pI 6.77) belonging to the S1OO family that is highly upregulated in psoriatic keratinocytes and whose expression patterns implied a role in the inflammatory response. Here we report that human psoriasin is a potent and selective chemotactic...... inflammatory protein for CD4+ T lymphocytes and neutrophils at concentrations of about 10(-11) M. Psoriasin is not structurally related to the alpha or the beta chemokine subfamilies or to lymphotactin, a member of a newly described class of chemokines. Thus, we have observed a chemotactic protein outside...

  3. Modulation of neutrophil and monocyte function by recombinant human granulocyte macrophage colony-stimulating factor in patients with lymphoma

    DEFF Research Database (Denmark)

    Kharazmi, A; Nielsen, H; Hovgaard, D;

    1991-01-01

    Granulocyte macrophage colony-stimulating factor (GM-CSF) has been shown to inhibit the chemotaxis and enhance the oxidative burst response of human neutrophils in vitro. The present study describes the effect of recombinant GM-CSF on the neutrophil and monocyte function in patients with lymphoma...

  4. The monocyte locomotion inhibitory factor an anti-inflammatory peptide; therapeutics originating from amebic abscess of the liver.

    Science.gov (United States)

    Velazquez, Juan R

    2011-01-01

    Entamoeba histolytica in culture produces a pentapeptide (MQCNS). This oligopeptide inhibits the in vitro and in vivo locomotion of human monocytes, hence its denomination Monocyte Locomotion Inhibitory Factor (MLIF). The original isolated peptide and its synthetic construct display similar effects, among others, being inhibition of the respiratory burst in monocytes and neutrophils, decrease of Dinitrochlorobenzene (DNCB) skin hypersensitivity in guinea pigs and gerbils, and delay of mononuclear leukocytes in human Rebuck skin windows with inhibition of vascular cell Very late antigen (VLA)-4 and Vascular adhesion molecules (VCAM) in endothelia and monocytes. The MLIF molecular mechanism of action is unknown, but data reveal its implication in Nuclear factor-kappa B (NF-κB) and Mitogenactivated protein kinase (MAPK) pathways. This could explain MLIF multiplicity of biological effects. On the other hand, the amebic peptide has been useful in treating experimental amebiasis of the liver. The amebic peptide is effective in reducing inflammation induced by carragenin and arthritis in a Collagen-induced arthritis (CIA) model. Microarray data from experimental arthritis revealed an MLIF gene expression profile that includes genes that are involved in apoptosis, cell adhesion, extracellular matrix, and inflammation / chemotaxis. MLIF could be involved in unsuspected biological factions because there is increasing data on the peptide effect on several cell activities. This review also presents uses of MLIF as described in patents.

  5. Monocyte chemotactic protein-4 (MCP-4/CCL-13) and CC ...

    African Journals Online (AJOL)

    EL-HAKIM

    function. It is thus likely that understanding the mechanisms of eosinophil recruitment to the airway will offer new .... healthy children without personal or family history of asthma or other ... quiescence was classified into intermittent asthma.

  6. Mactinin, a fragment of cytoskeletal α-actinin, is a novel inducer of heat shock protein (Hsp-90 mediated monocyte activation

    Directory of Open Access Journals (Sweden)

    Perri Robert T

    2009-08-01

    Full Text Available Abstract Background Monocytes, their progeny such as dendritic cells and osteoclasts and products including tumor necrosis factor (TNF-α, interleukin (IL-1α and IL-1β play important roles in cancer, inflammation, immune response and atherosclerosis. We previously showed that mactinin, a degradative fragment of the cytoskeletal protein α-actinin, is present at sites of monocytic activation in vivo, has chemotactic activity for monocytes and promotes monocyte/macrophage maturation. We therefore sought to determine the mechanism by which mactinin stimulates monocytes. Results Radiolabeled mactinin bound to a heterocomplex on monocytes comprised of at least 3 proteins of molecular weight 88 kD, 79 kD and 68 kD. Affinity purification, mass spectroscopy and Western immunoblotting identified heat shock protein (Hsp-90 as the 88 kD component of this complex. Hsp90 was responsible for mediating the functional effects of mactinin on monocytes, since Hsp90 inhibitors (geldanamycin and its analogues 17-allylamino-17-demethoxygeldanamycin [17-AAG] and 17-(dimethylaminoethylamino-17-demethoxygeldanamycin [17-DMAG] almost completely abrogated the stimulatory activity of mactinin on monocytes (production of the pro-inflammatory cytokines IL-1α, IL-1β and TNF-α, as well as monocyte chemotaxis. Conclusion Mactinin is a novel inducer of Hsp90 activity on monocytes and may serve to perpetuate and augment monocytic activation, thereby functioning as a "matrikine." Blockage of this function of mactinin may be useful in diseases where monocyte/macrophage activation and/or Hsp90 activity are detrimental.

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

    Directory of Open Access Journals (Sweden)

    Hsin-I Tong

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

  8. Monocyte-expressed urokinase regulates human vascular smooth muscle cell migration in a coculture model.

    Science.gov (United States)

    Kusch, Angelika; Tkachuk, Sergey; Lutter, Steffen; Haller, Hermann; Dietz, Rainer; Lipp, Martin; Dumler, Inna

    2002-01-01

    Interactions of vascular smooth muscle cells (VSMC) with monocytes recruited to the arterial wall at a site of injury, with resultant modulation of VSMC growth and migration, are central to the development of vascular intimal thickening. Urokinase-type plasminogen activator (uPA) expressed by monocytes is a potent chemotactic factor for VSMC and might serve for the acceleration of vascular remodeling. In this report, we demonstrate that coculture of human VSMC with freshly isolated peripheral blood-derived human monocytes results in significant VSMC migration that increases during the coculture period. Accordingly, VSMC adhesion was inhibited with similar kinetics. VSMC proliferation, however, was not affected and remained at the same basal level during the whole period of coculture. The increase of VSMC migration in coculture was equivalent to the uPA-induced migration of monocultured VSMC and was blocked by addition into coculture of soluble uPAR (suPAR). Analysis of uPA and uPAR expression in cocultured cells demonstrated that monocytes are a major source of uPA, whose expression increases in coculture five-fold, whereas VSMC display an increased expression of cell surface-associated uPAR. These findings indicate that upregulated uPA production by monocytes following vascular injury acts most likely as an endogenous activator of VSMC migration contributing to the remodeling of vessel walls.

  9. Glucocorticoids enhance the in vivo migratory response of human monocytes.

    Science.gov (United States)

    Yeager, Mark P; Pioli, Patricia A; Collins, Jane; Barr, Fiona; Metzler, Sara; Sites, Brian D; Guyre, Paul M

    2016-05-01

    Glucocorticoids (GCs) are best known for their potent anti-inflammatory effects. However, an emerging model for glucocorticoid (GC) regulation of in vivo inflammation also includes a delayed, preparatory effect that manifests as enhanced inflammation following exposure to an inflammatory stimulus. When GCs are transiently elevated in vivo following exposure to a stressful event, this model proposes that a subsequent period of increased inflammatory responsiveness is adaptive because it enhances resistance to a subsequent stressor. In the present study, we examined the migratory response of human monocytes/macrophages following transient in vivo exposure to stress-associated concentrations of cortisol. Participants were administered cortisol for 6h to elevate in vivo cortisol levels to approximate those observed during major systemic stress. Monocytes in peripheral blood and macrophages in sterile inflammatory tissue (skin blisters) were studied before and after exposure to cortisol or placebo. We found that exposure to cortisol induced transient upregulation of monocyte mRNA for CCR2, the receptor for monocyte chemotactic protein-1 (MCP-1/CCL2) as well as for the chemokine receptor CX3CR1. At the same time, mRNA for the transcription factor IκBα was decreased. Monocyte surface expression of CCR2 but not CX3CR1 increased in the first 24h after cortisol exposure. Transient exposure to cortisol also led to an increased number of macrophages and neutrophils in fluid derived from a sterile inflammatory site in vivo. These findings suggest that the delayed, pro-inflammatory effects of cortisol on the human inflammatory responses may include enhanced localization of effector cells at sites of in vivo inflammation.

  10. Commitment to the monocytic lineage occurs in the absence of the transcription factor PU.1.

    NARCIS (Netherlands)

    G.W. Henkel; S.R. McKercher; P.J. Leenen (Pieter); R.A. Maki

    1999-01-01

    textabstractMice homozygous for the disruption of the PU.1 (Spi-1) gene do not produce mature macrophages. In determining the role of PU.1 in macrophage differentiation, the present study investigated whether or not there was commitment to the monocytic lineage in the a

  11. Blood monocyte oxidative burst activity in acute P. falciparum malaria

    DEFF Research Database (Denmark)

    Nielsen, H; Theander, T G

    1989-01-01

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

  12. Identifying Cell Type-Specific Transcription Factors by Integrating ChIP-seq and eQTL Data-Application to Monocyte Gene Regulation.

    Science.gov (United States)

    Choudhury, Mudra; Ramsey, Stephen A

    2016-01-01

    We describe a novel computational approach to identify transcription factors (TFs) that are candidate regulators in a human cell type of interest. Our approach involves integrating cell type-specific expression quantitative trait locus (eQTL) data and TF data from chromatin immunoprecipitation-to-tag-sequencing (ChIP-seq) experiments in cell lines. To test the method, we used eQTL data from human monocytes in order to screen for TFs. Using a list of known monocyte-regulating TFs, we tested the hypothesis that the binding sites of cell type-specific TF regulators would be concentrated in the vicinity of monocyte eQTLs. For each of 397 ChIP-seq data sets, we obtained an enrichment ratio for the number of ChIP-seq peaks that are located within monocyte eQTLs. We ranked ChIP-seq data sets according to their statistical significances for eQTL overlap, and from this ranking, we observed that monocyte-regulating TFs are more highly ranked than would be expected by chance. We identified 27 TFs that had significant monocyte enrichment scores and mapped them into a protein interaction network. Our analysis uncovered two novel candidate monocyte-regulating TFs, BCLAF1 and SIN3A. Our approach is an efficient method to identify candidate TFs that can be used for any cell/tissue type for which eQTL data are available.

  13. Tick saliva increases production of three chemokines including monocyte chemoattractant protein-1, a histamine-releasing cytokine.

    Science.gov (United States)

    Langhansová, H; Bopp, T; Schmitt, E; Kopecký, J

    2015-02-01

    The effect of Ixodes ricinus tick saliva on the production of various cytokines and chemokines by mouse splenocytes was tested by a cytokine array. We demonstrated a strong upregulation of three chemokines, monocyte chemoattractant protein-1 (MCP-1), thymus-derived chemotactic agent 3 (TCA-3) and macrophage inflammatory protein 2 (MIP-2). MCP-1 could be induced by tick saliva itself. While TCA-3 and MIP-2 are engaged in Th2 polarization of the host immune response associated with tick feeding, MCP-1 may act as a histamine release factor, increasing blood flow into the feeding lesion thus facilitating tick engorgement in the late, rapid feeding phase.

  14. Microparticles engineered to highly express peroxisome proliferator-activated receptor-γ decreased inflammatory mediator production and increased adhesion of recipient monocytes.

    Directory of Open Access Journals (Sweden)

    Julie Sahler

    Full Text Available Circulating blood microparticles are submicron vesicles released primarily by megakaryocytes and platelets that act as transcellular communicators. Inflammatory conditions exhibit elevated blood microparticle numbers compared to healthy conditions. Direct functional consequences of microparticle composition, especially internal composition, on recipient cells are poorly understood. Our objective was to evaluate if microparticle composition could impact the function of recipient cells, particularly during inflammatory provocation. We therefore engineered the composition of megakaryocyte culture-derived microparticles to generate distinct microparticle populations that were given to human monocytes to assay for influences recipient cell function. Herein, we tested the responses of monocytes exposed to either control microparticles or microparticles that contain the anti-inflammatory transcription factor, peroxisome proliferator-activated receptor-γ (PPARγ. In order to normalize relative microparticle abundance from two microparticle populations, we implemented a novel approach that utilizes a Nanodrop Spectrophotometer to assay for microparticle density rather than concentration. We found that when given to peripheral blood mononuclear cells, microparticles were preferentially internalized by CD11b+ cells, and furthermore, microparticle composition had a profound functional impact on recipient monocytes. Specifically, microparticles containing PPARγ reduced activated monocyte production of the proinflammatory cytokines interleukin-8 and monocyte chemotactic protein-1 compared to activated monocytes exposed to control microparticles. Additionally, treatment with PPARγ microparticles greatly increased monocyte cell adherence. This change in morphology occurred simultaneously with increased production of the key extracellular matrix protein, fibronectin and increased expression of the fibronectin-binding integrin, ITGA5. PPARγ microparticles

  15. Sphingosylphosphorylcholine stimulates human monocyte-derived dendritic cell chemotaxis

    Institute of Scientific and Technical Information of China (English)

    Ha-young LEE; Eun-ha SHIN; Yoe-sik BAE

    2006-01-01

    Aim: To investigate the effects of Sphingosylphosphorylcholine (SPC) on human monocyte-derived dendritic cell (DC) chemotaxis. Methods: Human DC were generated from peripheral blood monocytes by culturing them with granulocyte macrophage-colony stimulating factor and interleukin-4. The effect of SPC on the DC chemotactic migration was measured by chemotaxis assay. Intracellular signaling event involved in the SPC-induced DC chemotaxis was investigated with several inhibitors for specific kinase. The expression of the SPC receptors was examined by reverse transcription polymerase chain reaction. Results: We found that SPC induced chemotactic migration in immature DC (iDC) and mature DC (mDC). In terms of SPC-induced signaling events, mitogen activated protein kinase activation and Akt activation in iDC and mDC were stimulated. SPC-induced chemotaxis was mediated by extracellular signal-regulated protein kinase and phosphoino-sitide-3-kinase, but not by calcium in both iDC and mDC. Although mDC express ovarian cancer G protein-coupled receptor 1, but not G protein-coupled receptor 4, iDC do not express any of these receptors. To examine the involvement of sphin-gosine-1-phosphate (SIP) receptors, we checked the effect of an SIP receptor antagonist (VPC23019) on SPC-induced DC chemotaxis. VPC23019 did not affect SPC-induced DC chemotaxis. Conclusion: The results suggest that SPC may play a role in regulating DC trafficking during phagocytosis and the T cell-stimulating phase, and the unique SPC receptor, which is different from SIP receptors, is involved in SPC-induced chemotaxis.

  16. Human monocytes/macrophages are a target of Neisseria meningitidis Adhesin A (NadA).

    Science.gov (United States)

    Franzoso, Susanna; Mazzon, Cristina; Sztukowska, Maryta; Cecchini, Paola; Kasic, Tihana; Capecchi, Barbara; Tavano, Regina; Papini, Emanuele

    2008-05-01

    Specific surface proteins of Neisseria meningitidis have been proposed to stimulate leukocytes during tissue invasion and septic shock. In this study, we demonstrate that the adhesin N. meningitidis Adhesin A (NadA) involved in the colonization of the respiratory epithelium by hypervirulent N. meningitidis B strains also binds to and activates human monocytes/macrophages. Expression of NadA on the surface on Escherichia coli does not increase bacterial-monocyte association, but a NadA-positive strain induced a significantly higher amount of TNF-alpha and IL-8 compared with the parental NadA-negative strain, suggesting that NadA has an intrinsic stimulatory action on these cells. Consistently, highly pure, soluble NadA(Delta351-405), a proposed component of an antimeningococcal vaccine, efficiently stimulates monocytes/macrophages to secrete a selected pattern of cytokines and chemotactic factors characterized by high levels of IL-8, IL-6, MCP-1, and MIP-1alpha and low levels of the main vasoactive mediators TNF-alpha and IL-1. NadA(Delta351-405) also inhibited monocyte apoptosis and determined its differentiation into a macrophage-like phenotype.

  17. Bole of macrophage colony-stimulating factor in the differentiation and expansion of monocytes and dendritic cells from CD34(+) progenitor cells

    NARCIS (Netherlands)

    Kamps, AWA; Smit, JW; Vellenga, E

    1999-01-01

    The present study focused on whether it is possible to expand monocytic cells from CD34(+) progenitor cells by using macrophage colony-stimulating factor (M-CSF) in the absence and presence of mast cell growth factor (MGF) and IL-6. It was demonstrated that CD34(+) cells differentiate without expans

  18. Stimulation of monocytes by placental microparticles involves toll-like receptors and nuclear factor kappa-light-chain-enhancer of activated B cells.

    Science.gov (United States)

    Joerger-Messerli, Marianne Simone; Hoesli, Irene Mathilde; Rusterholz, Corinne; Lapaire, Olav

    2014-01-01

    Human pregnancy is accompanied by a mild systemic inflammatory response, which includes the activation of monocytes circulating in maternal blood. This response is exaggerated in preeclampsia, a placental-dependent disorder specific to human pregnancies. We and others showed that placental syncytiotrophoblast membrane microparticles (STBM) generated in vitro from normal placentas stimulated peripheral blood monocytes, which suggest a contribution of STBM to the systemic maternal inflammation. Here, we analyzed the inflammatory potential of STBM prepared from preeclamptic placentas on primary monocytes and investigated the mode of action in vitro. STBM generated in vitro by placental villous explants of normal or preeclamptic placentas were co-incubated with human peripheral blood monocytes. In some cases, inhibitors of specific cellular functions or signaling pathways were used. The analysis of the monocytic response was performed by flow cytometry, enzyme-linked immunoassays, real-time PCR, and fluorescence microscopy. STBM derived from preeclamptic placentas up-regulated the cell surface expression of CD54, and stimulated the secretion of the pro-inflammatory interleukin (IL)-6 and IL-8 in a similar, dose-dependent manner as did STBM prepared from normal placentas. STBM bound to the cell surface of monocytes, but phagocytosis was not necessary for activation. STBM-induced cytokine secretion was impaired in the presence of inhibitors of toll-like receptor (TLR) signaling or when nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) activation was blocked. Our results suggest that the inflammatory reaction in monocytes may be initiated by the interaction of STBM with TLRs, which in turn signal through NF-κB to mediate the transcription of genes coding for pro-inflammatory factors.

  19. Stimulation of monocytes by placental microparticles involves Toll-like receptors and nuclear factor kappa-light-chain-enhancer of activated B cells

    Directory of Open Access Journals (Sweden)

    Marianne Simone Joerger-Messerli

    2014-04-01

    Full Text Available Human pregnancy is accompanied by a mild systemic inflammatory response, which includes the activation of monocytes circulating in maternal blood. This response is exaggerated in preeclampsia, a placental-dependent disorder specific to human pregnancies. We and others showed that placental syncytiotrophoblast membrane microparticles (STBM generated in vitro from normal placentas stimulated peripheral blood monocytes, which suggests a contribution of STBM to the systemic maternal inflammation. Here, we analyzed the inflammatory potential of STBM prepared from preeclamptic placentas on primary monocytes and investigated the mode of action in vitro.STBM generated in vitro by placental villous explants of normal or preeclamptic placentas were co-incubated with human peripheral blood monocytes. In some cases, inhibitors of specific cellular functions or signaling pathways were used. The analysis of the monocytic response was performed by flow cytometry, enzyme-linked immunoassays, real-time PCR and fluorescence microscopy.STBM derived from preeclamptic placentas up-regulated the cell surface expression of CD54, and stimulated the secretion of the pro-inflammatory interleukin (IL-6 and IL-8 in a similar, dose-dependent manner as did STBM prepared from normal placentas. STBM bound to the cell surface of monocytes, but phagocytosis was not necessary for activation. STBM-induced cytokine secretion was impaired in the presence of inhibitors of toll-like receptor (TLR signaling or when nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB activation was blocked.Our results suggest that the inflammatory reaction in monocytes may be initiated by the interaction of STBM with TLRs, which in turn signal through NF-κB to mediate the transcription of genes coding for pro-inflammatory factors.

  20. Correlation of pathogenesis of Toll-like receptor and chemotactic factor with lyme arthritis%Toll样受体和趋化因子与莱姆关节炎发病的相关性

    Institute of Scientific and Technical Information of China (English)

    汪玉娇; 宝福凯; 柳爱华

    2012-01-01

    莱姆病是一种由伯氏疏螺旋体引起,经蜱传播的自然疫源性疾病,也是一种人兽共患病,莱姆关节炎是莱姆病的晚期临床表现,严重者可终生致残,严重影响了人们的健康和生活质量,目前,对莱姆关节炎的致病机制尚不清楚,国内外已经取得了一系列进展,但有待进一步研究.现就Toll样受体和趋化因子与莱姆关节炎发病关系的研究做一综述.%Lyme disease, which is caused by Borrelia burgdorferi and spread by ticks, is a kind of natural foci disease and parasitic zoonoses. Lyme Arthritis is the late clinical manifestation of Lyme disease, it can make patients in lifelong disability in some severe cases and seriously affect healthy and life quality of patients. Until now, We still don't understand the pathogenic mechanism of Lyme Arthritis clearly, although there is a serious progress about it at home and aboard, further study on it is necessary. This article is intent to summarize the researches on relationship between Toll-like receptor, chemotactic factor and Lyme Arthritis.

  1. SP600125对1型糖尿病小鼠颈动脉内皮功能及单核细胞趋化蛋白1表达的影响%The Effect of SP600125 on Endothelial Function and Monocyte Chemotactic Protein-1 Expression in Carotid Artery in Type 1 Diabetic Mice

    Institute of Scientific and Technical Information of China (English)

    王启章; 陈茂刚; 李达文; 刘朝来; 徐格林; 刘新峰

    2011-01-01

    Aim The incidence of stroke in diabetes is increasing seriously, which is associated with endothelial dysfunction and increased inflammation in carotid artery.Our study is to investigate the effect of c-Jun arnino-terminal ki-nase (JNK) specific inhibitor SP600125 on carotid endothelial function and monocyte chemotactic protein-1 (MCP-1) expression in type 1 diabetes. Methods Animals were divided into five groups in this study. The 1st group was C57BL/6 wild type male mice; the 2nd group was INS2AKUTI male mice, intraperitoneal injection with 0. 9% normal saline (NS) each day for 8 weeks; the 3rd, 4th, 5th group were INS2AKITA male mice, intraperitoneal injection with SP600125 10 mg/kg, 20 mg/kg, 30 mg/kg respectively each day for consecutive 8 weeks. Then the mice were killed and sreum my-eloperoxidase (MPO) , malondialdehyde (MDA) , nitric oxide (NO) , total nitric oxide synthase (TNOS) were measured. HE staining was performed in carotid artery and immunohistochemistry was performed to investigate MCP-1 protein expression in endothelial cells of carotid artery. P-JNK, JNK, MCP-1 protein expression in carotid artery was measured by Western blot, signal transducer and activator of transcription-1 (STAT-1) DNA binding activity was assayed by electro-phoretic mobility shift assay (EMSA). Results Compared with wild type mice, serum MPO and MDA expression increased prominently (P <0. 05) , whereas TNOS, NO decreased and p-JNK/JNK, MCP-1 expression increased significantly in INS2AKITA mice (P<0.05); STAT-1 DNA binding activity increased prominently in type 1 diabetic group compared with that in control group (P <0. 05). Compared with type 1 diabetic mice, after treatment with SP600125, MPO decreased and NO, TNOS increased and p-JNK/JNK, endothelial MCP-1 expression decreased (P<0. 05). The effects of SP600125 on MPO, NO, TNOS, MCP-1 were increased accordingly as the dose of SP600125 increased. As the dose of SP600125 increased, MCP-1 protein expression decreased 21. 82

  2. Cholesterol enrichment of human monocyte/macrophages induces surface exposure of phosphatidylserine and the release of biologically-active tissue factor-positive microvesicles.

    Science.gov (United States)

    Liu, Ming-Lin; Reilly, Michael P; Casasanto, Peter; McKenzie, Steven E; Williams, Kevin Jon

    2007-02-01

    Biologically significant amounts of two procoagulant molecules, phosphatidylserine (PS) and tissue factor (TF), are transported by monocyte/macrophage-derived microvesicles (MVs). Because cellular cholesterol accumulation is an important feature of atherosclerotic vascular disease, we now examined effects of cholesterol enrichment on MV release from human monocytes and macrophages. Cholesterol enrichment of human THP-1 monocytes, alone or in combination with lipopolysaccharide (LPS), tripled their total MV generation, as quantified by flow cytometry based on particle size and PS exposure. The subset of these MVs that were also TF-positive was likewise increased by cellular cholesterol enrichment, and these TF-positive MVs exhibited a striking 10-fold increase in procoagulant activity. Moreover, cholesterol enrichment of primary human monocyte-derived macrophages also increased their total as well as TF-positive MV release, and these TF-positive MVs exhibited a similar 10-fold increase in procoagulant activity. To explore the mechanisms of enhanced MV release, we found that cholesterol enrichment of monocytes caused PS exposure on the cell surface by as early as 2 hours and genomic DNA fragmentation in a minority of cells by 20 hours. Addition of a caspase inhibitor at the beginning of these incubations blunted both cholesterol-induced apoptosis and MV release. Cholesterol enrichment of human monocyte/macrophages induces the generation of highly biologically active, PS-positive MVs, at least in part through induction of apoptosis. Cholesterol-induced monocyte/macrophage MVs, both TF-positive and TF-negative, may be novel contributors to atherothrombosis.

  3. Pathogenic bacteria and TNF do not induce production of macrophage migration inhibitory factor (MIF) by human monocytes.

    Science.gov (United States)

    Temple, Suzanna E L; Cheong, Karey Y; Price, Patricia; Waterer, Grant W

    2009-06-01

    Elevated serum macrophage migration inhibitory factor (MIF) is associated with severe sepsis, but it is not clear whether bacteria stimulate synthesis of MIF by blood leukocytes directly or via induction of TNF. Here we assess production of MIF mRNA and protein by blood leukocytes from healthy human subjects (n=28) following exposure to bacteria commonly associated with sepsis (Escherichia coli and Streptococcus pneumoniae). Bacteria did not increase levels of MIF mRNA or secreted protein. CD14(+) monocytes were the main cell type producing MIF before and after stimulation. Exposure of leukocytes to TNF did not induce MIF. Hence elevated levels of serum MIF observed in sepsis may not reflect MIF produced by blood leukocytes stimulated directly by bacteria or TNF.

  4. Current Status of Monocyte Differentiation-Inducing (MDI Factors Derived from Human Fetal Membrane Chorion Cells Undergoing Apoptosis after Infl uenza Virus Infection

    Directory of Open Access Journals (Sweden)

    Noboru Uchide

    2007-01-01

    Full Text Available Influenza virus infection induces apoptosis and the expression of a set of pro-inflammatory cytokine genes, such as interleukin (IL-6, tumor necrosis factor (TNF-α, interferon (IFN-β and IFN-γ, in cultured human fetal membrane chorion cells. Monocyte differentiation-inducing (MDI activity in culture supernatants is simultaneously increased by the virus infection. The MDI activity is predominantly influenced by IL-6 molecule in culture supernatants, and partly by TNF-α and IFN-β, but not IFN-γ, molecules. The MDI factors are able to induce the mRNA expression of macrophage class A scavenger receptor (SR-A, which is one of adhesion and apoptotic cell-recognizing molecules, and gp91phox, which is a catalytic subunit of reduced nicotinamide adenine dinucleotide phosphate (NADPH oxidase enzyme complex, on monocytic cells. As a result, monocytes are initiated to differentiate into well-matured macrophages capable of adhering and producing superoxide through NADPH oxidase. The matured macrophages, obtained from human monocytic leukemia THP-1 cells by the treatment with MDI factors, phagocytose apoptotic chorion cell debris resulting from the virus infection. Subsequent to phagocytosis, an abrupt increase of superoxide production by macrophages may occur. In this article, we summarize recent knowledge about the MDI factors derived from human fetal membrane chorion cells undergoing apoptosis after influenza virus infection, and discuss their possible pathological roles during pregnancy.

  5. Improved antitumor response to isolated limb perfusion with tumor necrosis factor after upregulation of endothelial monocyte-activating polypeptide II in soft tissue sarcoma

    NARCIS (Netherlands)

    T.E. Lans; T.L.M. ten Hagen (Timo); R. van Horssen (Remco); P.C. Wu; S.T. van Tiel (Sandra); S.K. Libutti; H.R. Alexander; A.M.M. Eggermont (Alexander)

    2002-01-01

    textabstractBACKGROUND: Experiments with tumor necrosis factor alpha (TNF) in rodents have shown that a high dose can lead to hemorrhagic necrosis in tumors. Endothelial monocyte-activating polypeptide II (EMAP-II) is a novel tumor-derived cytokine, and its expression increases the

  6. Human monocyte-derived insulin-like growth factor-2 enhances the infection of human arterial endothelial cells by Chlamydia pneumoniae.

    Science.gov (United States)

    Lin, T M; Campbell, L A; Rosenfeld, M E; Kuo, C C

    2001-05-01

    It has been shown that infection of human endothelial cells by Chlamydia pneumoniae is enhanced by co-culturing endothelial cells with human monocytes and is mediated by monocyte-derived soluble factors. This study was conducted to identify the infectivity-enhancing factor. Serum-free conditioned medium of human monocytic cells was fractionated by ultrafiltration. The enhancing activity was found in the fraction in the molecular mass range between 5000 and 10,000 kDa. Recombinant human insulin-like growth factor (IGF)-1 or -2, with a molecular mass of 7500 kDa, was added to the culture medium of human endothelial cells for growing C. pneumoniae. Only IGF-2 enhanced C. pneumoniae growth. Pretreatment of the conditioned medium with a monoclonal antibody against IGF-2 blocked the enhancing activity. This suggests that the infectivity-enhancing factor is IGF-2 and that paracrine interactions between monocytes and endothelial cells in vivo can induce secretory products and sustain infection with C. pneumoniae within atherosclerotic lesions.

  7. Polarised clathrin-mediated endocytosis of EGFR during chemotactic invasion.

    Science.gov (United States)

    Mutch, Laura Jane; Howden, Jake Davey; Jenner, Emma Poppy Louise; Poulter, Natalie Sarah; Rappoport, Joshua Zachary

    2014-06-01

    Directed cell migration is critical for numerous physiological processes including development and wound healing. However chemotaxis is also exploited during cancer progression. Recent reports have suggested links between vesicle trafficking pathways and directed cell migration. Very little is known about the potential roles of endocytosis pathways during metastasis. Therefore we performed a series of studies employing a previously characterised model for chemotactic invasion of cancer cells to assess specific hypotheses potentially linking endocytosis to directed cell migration. Our results demonstrate that clathrin-mediated endocytosis is indispensable for epidermal growth factor (EGF) directed chemotactic invasion of MDA-MB-231 cells. Conversely, caveolar endocytosis is not required in this mode of migration. We further found that chemoattractant receptor (EGFR) trafficking occurs by clathrin-mediated endocytosis and is polarised towards the front of migrating cells. However, we found no role for clathrin-mediated endocytosis in focal adhesion disassembly in this migration model. Thus, this study has characterised the role of endocytosis during chemotactic invasion and has identified functions mechanistically linking clathrin-mediated endocytosis to directed cell motility.

  8. Lower concentrations of chemotactic cytokines and soluble innate factors in the lower female genital tract associated with the use of injectable hormonal contraceptive.

    Science.gov (United States)

    Ngcapu, Sinaye; Masson, Lindi; Sibeko, Sengeziwe; Werner, Lise; McKinnon, Lyle R; Mlisana, Koleka; Shey, Muki; Samsunder, Natasha; Karim, Salim Abdool; Karim, Quarraisha Abdool; Passmore, Jo-Ann S

    2015-08-01

    Progesterone-based injectable hormonal contraceptives (HCs) potentially modulate genital barrier integrity and regulate the innate immune environment in the female genital tract, thereby enhancing the risk of STIs or HIV infection. We investigated the effects of injectable HC use on concentrations of inflammatory cytokines and other soluble factors associated with genital epithelial repair and integrity. The concentrations of 42 inflammatory, regulatory, adaptive growth factors and hematopoietic cytokines, five matrix metalloproteinases (MMPs), and four tissue inhibitors of metalloproteinases (TIMPs) were measured in cervicovaginal lavages (CVLs) from 64 HIV-negative women using injectable HCs and 64 control women not using any HCs, in a matched case-control study. There were no differences between groups in the prevalence of bacterial vaginosis (BV; Nugent score ≥7), or common sexually transmitted infections (STIs). In multivariate analyses adjusting for condom use, sex work status, marital status, BV and STIs, median concentrations of chemokines (eotaxin, MCP-1, MDC), adaptive cytokines (IL-15), growth factors (PDGF-AA) and a metalloproteinase (TIMP-2) were significantly lower in CVLs from women using injectable HCs than controls. In addition, the pro-inflammatory cytokine IL-12p40 and the chemokine fractalkine were less likely to have detectable levels in women using injectable HCs compared with those not using HCs. We conclude that injectable HC use was broadly associated with an immunosuppressive female genital tract innate immune profile. While the relationship between injectable HC use and STI or HIV risk is yet to be resolved, our data suggest that the effects of injectable HCs were similar in STI-positive and STI-negative participants.

  9. Predictive factors of clinical response in steroid-refractory ulcerative colitis treated with granulocyte-monocyte apheresis

    Institute of Scientific and Technical Information of China (English)

    Valeria D'Ovidio; Donatella Meo; Angelo Viscido; Giampaolo Bresci; Piero Vernia; Renzo Caprilli

    2011-01-01

    AIM: To identify factors predicting the clinical response of ulcerative colitis patients to granulocyte-monocyte apheresis (GMA).METHODS: Sixty-nine ulcerative colitis patients (39 F, 30 M) dependent upon/refractory to steroids were treated with GMA.Steroid dependency, clinical activity index (CAI), C reactive protein (CRP) level, erythrocyte sedimentation rate (ESR), values at baseline, use of immunosuppressant, duration of disease, and age and extent of disease were considered for statistical analysis as predictive factors of clinical response.Univariate and multivariate logistic regression models were used.RESULTS: In the univariate analysis, CAI (P = 0.039) and ESR (P = 0.017) levels at baseline were singled out as predictive of clinical remission.In the multivariate analysis steroid dependency [Odds ratio (OR) = 0.390, 95% Confidence interval (CI): 0.176-0.865, Wald 5.361, P = 0.0160] and low CAI levels at baseline (4 < CAI < 7) (OR = 0.770, 95% CI: 0.425-1.394, Wald 3.747, P = 0.028) proved to be effective as factors predicting clinical response.CONCLUSION: GMA may be a valid therapeutic option for steroid-dependent ulcerative colitis patients with mild-moderate disease and its clinical efficacy seems to persist for 12 mo.

  10. Predictive factors of clinical response in steroid-refractory ulcerative colitis treated with granulocyte-monocyte apheresis.

    Science.gov (United States)

    D'Ovidio, Valeria; Meo, Donatella; Viscido, Angelo; Bresci, Giampaolo; Vernia, Piero; Caprilli, Renzo

    2011-04-14

    To identify factors predicting the clinical response of ulcerative colitis patients to granulocyte-monocyte apheresis (GMA). Sixty-nine ulcerative colitis patients (39 F, 30 M) dependent upon/refractory to steroids were treated with GMA. Steroid dependency, clinical activity index (CAI), C reactive protein (CRP) level, erythrocyte sedimentation rate (ESR), values at baseline, use of immunosuppressant, duration of disease, and age and extent of disease were considered for statistical analysis as predictive factors of clinical response. Univariate and multivariate logistic regression models were used. In the univariate analysis, CAI (P = 0.039) and ESR (P = 0.017) levels at baseline were singled out as predictive of clinical remission. In the multivariate analysis steroid dependency [Odds ratio (OR) = 0.390, 95% Confidence interval (CI): 0.176-0.865, Wald 5.361, P = 0.0160] and low CAI levels at baseline (4 < CAI < 7) (OR = 0.770, 95% CI: 0.425-1.394, Wald 3.747, P = 0.028) proved to be effective as factors predicting clinical response. GMA may be a valid therapeutic option for steroid-dependent ulcerative colitis patients with mild-moderate disease and its clinical efficacy seems to persist for 12 mo.

  11. Urine Monocyte Chemoattractant Protein-1 Is an Independent Predictive Factor of Hospital Readmission and Survival in Cirrhosis.

    Directory of Open Access Journals (Sweden)

    Isabel Graupera

    Full Text Available MCP-1 (monocyte chemoattractant protein-1 is a proinflammatory cytokine involved in chemotaxis of monocytes. In several diseases, such as acute coronary syndromes and heart failure, elevated MCP-1 levels have been associated with poor outcomes. Little is known about MCP-1 in cirrhosis.To investigate the relationship between MCP-1 and outcome in decompensated cirrhosis.Prospective study of 218 patients discharged from hospital after an admission for complications of cirrhosis. Urine and plasma levels of MCP-1 and other urine proinflammatroy biomarkers: osteopontin(OPN, trefoil-factor3 and liver-fatty-acid-binding protein were measured at admission. Urine non-inflammatory mediators cystatin-C, β2microglobulin and albumin were measured as control biomarkers. The relationship between these biomarkers and the 3-month hospital readmission, complications of cirrhosis, and mortality were assessed.69 patients(32% had at least one readmission during the 3-month period of follow-up and 30 patients died(14%. Urine MCP-1 and OPN levels, were associated with 3-month probability of readmission (0.85 (0.27-2.1 and 2003 (705-4586 ug/g creat vs 0.47 (0.2-1.1 and 1188 (512-2958 ug/g creat, in patients with and without readmission, respectively; p<0.05; median (IQR. Furthermore, urine levels of MCP-1 were significantly associated with mortality (1.01 (1-3.6 vs 0.5 (0.2-1.1 μg/g creat, in dead and alive patients at 3 months; p<0.05. Patients with higher levels of urine MCP-1 (above percentile 75th had higher probability of development of hepatic encephalopathy, bacterial infections or AKI. Urine MCP-1 was an independent predictive factor of hospital readmission and combined end-point of readmission or dead at 3 months. Plasma levels of MCP-1 did not correlated with outcomes.Urine, but not plasma, MCP-1 levels are associated with hospital readmission, development of complications of cirrhosis, and mortality. These results suggest that in cirrhosis there is an

  12. Potential Role of Vascular Endothelial Growth Factor, Interleukin-8 and Monocyte Chemoattractant Protein-1 in Periodontal Diseases

    Directory of Open Access Journals (Sweden)

    En Lee

    2003-08-01

    Full Text Available Host-mediated immunoinflammatory pathways activated by bacteria lead to destruction of the periodontal connective tissues and alveolar bone. The objective of this study was to elucidate the activation of the inflammatory processes in periodontal disease by quantitative assessment of cytokines and periodontopathogens. Gingival crevicular fluids (GCF and subgingival plaque samples were collected from patients with chronic periodontitis and gingivitis and from periodontally healthy sites. Vascular endothelial growth factor (VEGF, monocyte chemoattractant protein-1 (MCP-1, and interleukin 8 (IL-8 in GCF were analyzed by enzyme-linked immunosorbent assay. Periodontopathogens, including Bacteroides forsythus, Campylobacter rectus, Porphyromonas gingivalis and Prevotella intermedia, were analyzed by immunofluorescence and dark-field microscopy. There was significantly more VEGF and IL-8 in chronic periodontitis and gingivitis sites than in periodontally healthy sites. There were significant positive correlations between the concentrations and total amounts of VEGF and IL-8 in chronic periodontitis and gingivitis sites, and between the levels of periodontopathogens and the total amounts of VEGF, MCP-1 and IL-8. These data indicate that inflammatory processes induced by periodontopathogens and the activation of certain cytokines (VEGF, MCP-1, IL-8 in periodontal diseases may be relevant to host-mediated destruction in chronic periodontitis.

  13. Cytokine expression in CD4(+) cells exposed to the monocyte locomotion inhibitory factor produced by Entamoeba histolytica.

    Science.gov (United States)

    Rojas-Dotor, Sara; Rico, Guadalupe; Pérez, Julia; Velázquez, Juan; Silva, Raúl; Morales, Esther; Kretschmer, Roberto

    2006-04-01

    Entamoeba histolytica produces monocyte locomotion inhibitory factor (MLIF), a pentapeptide with in vitro and in vivo anti-inflammatory properties. MLIF may interfere with leukocyte migration, disturbing the balance of pro- and anti-inflammatory cytokines secreted by CD4(+) T lymphocytes. We evaluated the effect of MLIF on expression of pro- and anti-inflammatory cytokines in human CD4(+) T lymphocytes. Regulatory cytokines [interleukin-1 beta (IL-1beta), IL-2, interferon gamma (IFN-gamma), IL-5, IL-6, and IL-10] were studied by enzyme-linked immunosorbent assay method in CD4(+)-cell supernatant fluids. Proinflammatory cytokines were produced per se by MLIF (IL-1beta, IL-2, and IFN-gamma) and also anti-inflammatory cytokines (IL-5, IL-6, and IL-10) with 1-phorbol-12 myristate-13 acetate + MLIF; the IL-1beta, IFN-gamma, IL-5 and IL-6 production was inhibited but not that of IL-10 which disclosed increase in its expression. MLIF disturbs the pro- and anti-inflammatory balance, and it induces inhibition of IL-1beta (principal proinflammatory cytokine) and increases IL-10 (prototype of an anti-inflammatory cytokine).

  14. Matrix metalloproteinase-9 and stromal cell-derived factor-1 act synergistically to support migration of blood-borne monocytes into the injured spinal cord.

    Science.gov (United States)

    Zhang, Haoqian; Trivedi, Alpa; Lee, Jung-Uek; Lohela, Marja; Lee, Sang Mi; Fandel, Thomas M; Werb, Zena; Noble-Haeusslein, Linda J

    2011-11-01

    The infiltration of monocytes into the lesioned site is a key event in the inflammatory response after spinal cord injury (SCI). We hypothesized that the molecular events governing the infiltration of monocytes into the injured cord involve cooperativity between the upregulation of the chemoattractant stromal cell-derived factor-1 (SDF-1)/CXCL12 in the injured cord and matrix metalloproteinase-9 (MMP-9/gelatinase B), expressed by infiltrating monocytes. SDF-1 and its receptor CXCR4 mRNAs were upregulated in the injured cord, while macrophages immunoexpressed CXCR4. When mice, transplanted with bone marrow cells from green fluorescent protein (GFP) transgenic mice, were subjected to SCI, GFP+ monocytes infiltrated the cord and displayed gelatinolytic activity. In vitro studies confirmed that SDF-1α, acting through CXCR4, expressed on bone marrow-derived macrophages, upregulated MMP-9 and stimulated MMP-9-dependent transmigration across endothelial cell monolayers by 2.6-fold. There was a reduction in F4/80+ macrophages in spinal cord-injured MMP-9 knock-out mice (by 36%) or wild-type mice, treated with the broad-spectrum MMP inhibitor GM6001 (by 30%). Mice were adoptively transferred with myeloid cells and treated with the MMP-9/-2 inhibitor SB-3CT, the CXCR4 antagonist AMD3100, or a combination of both drugs. While either drug resulted in a 28-30% reduction of infiltrated myeloid cells, the combined treatment resulted in a 45% reduction, suggesting that SDF-1 and MMP-9 function independently to promote the trafficking of myeloid cells into the injured cord. Collectively, these observations suggest a synergistic partnership between MMP-9 and SDF-1 in facilitating transmigration of monocytes into the injured spinal cord.

  15. IVIG inhibits TNF-α-induced MMP9 expression and activity in monocytes by suppressing NF-κB and P38 MAPK activation.

    Science.gov (United States)

    Zhou, Cuizhen; Huang, Min; Xie, Lijian; Shen, Jie; Xiao, Tingting; Wang, Renjian

    2015-01-01

    Matrix metalloproteinase-9 (MMP9) has been involved in inflammatory and pathologic processes of coronary artery lesions (CAL) in Kawasaki disease (KD). Intravenous immunoglobulin (IVIG), a traditional treatment for Kawasaki disease, could decrease the expressions of MMP9. The purpose of this study was to investigate the protective effect of IVIG in chemotactic migration of monocyte and the regulation of MMP9 induced by tumor necrosis factor-α (TNF-α) in U937s. Studies were carried out with real time polymerase chain reaction (RT-PCR), zymographic, Western blotting and immunofluorescence. U937s' migration was enhanced by TNF-α stimulation, while was inhibited by IVIG pretreatment. MMP9 expression and activity in U937s were also significantly enhanced by TNF-α and inhibited by IVIVG pretreatment. During inflammatory stimulus, nuclear factor kappa B (NF-κB) and P38 Mitogenactivated protein kinase (P38 MAPK) pathways play a significant role in regulating MMP9 gene expression. TNF-α induced nuclear translocation of NF-κB and P38 MAPK activation in U937s were inhibited significantly by IVIG. Furthermore, we clarified that nuclear NF-κB and P38 MAPK pathways play pivotal roles in regulating U937s' migration and MMP9 expressions using PDTC and SB203580, which were specific inhibitors of NF-κB and p38 MAPK pathways. IVIG displays striking biological effects, notably promoting monocyte migration. These effects involve the NF-κB and p38 pathways, and increased MMP9 activity. It might be a crucial mechanism of IVIG reducing the occurrence of CAL that IVIG inhibited monocytes expressing MMP9 and decreased chemotactic migration of monocyte.

  16. Effects of Tumor Necrosis Factor-α on Podocyte Expression of Monocyte Chemoattractant Protein-1 and in Diabetic Nephropathy

    Directory of Open Access Journals (Sweden)

    Choon Hee Chung

    2015-02-01

    Full Text Available Background/Aims: Tumor necrosis factor (TNF-α is believed to play a role in diabetic kidney disease. This study explores the specific effects of TNF-α with regard to nephropathy-relevant parameters in the podocyte. Methods: Cultured mouse podocytes were treated with recombinant TNF-α and assayed for production of monocyte chemoattractant protein-1 (MCP-1 by enzyme-linked immunosorbent assay (ELISA. TNF-α signaling of MCP-1 was elucidated by antibodies against TNF receptor (TNFR 1 or TNFR2 or inhibitors of nuclear factor-kappaB (NF-κB, phosphatidylinositol 3-kinase (PI3K or Akt. In vivo studies were done on male db/m and type 2 diabetic db/db mice. Levels of TNF-α and MCP-1 were measured by RT-qPCR and ELISA in the urine, kidney and plasma of the two cohorts and correlated with albuminuria. Results: Podocytes treated with TNF-α showed a robust increase (∼900% in the secretion of MCP-1, induced in a dose- and time-dependent manner. Signaling of MCP-1 expression occurred through TNFR2, which was inducible by TNF-α ligand, but did not depend on TNFR1. TNF-α then proceeded via the NF-κB and the PI3K/Akt systems, based on the effectiveness of the inhibitors of those pathways. For in vivo relevance to diabetic kidney disease, TNF-α and MCP-1 levels were found to be elevated in the urine of db/db mice but not in the plasma. Conclusion: TNF-α potently stimulates podocytes to produce MCP-1, utilizing the TNFR2 receptor and the NF-κB and PI3K/Akt pathways. Both TNF-α and MCP-1 levels were increased in the urine of diabetic db/db mice, correlating with the severity of diabetic albuminuria.

  17. Beneifcial effect of reifned red palm oil on lipid peroxidation and monocyte tissue factor in HCV-related liver disease:a randomized controlled study

    Institute of Scientific and Technical Information of China (English)

    Roberto Catanzaro; Nicola Zerbinati; Umberto Solimene; Massimiliano Marcellino; Dheeraj Mohania; Angelo Italia; Antonio Ayala; Francesco Marotta

    2016-01-01

    BACKGROUND: A large amount of endotoxin can be detected in the peripheral venous blood of patients with liver cirrhosis, contributing to the pathogenesis of hepatotoxicity because of its role in oxidative stress. The present study aimed to test the effect of the supplementation with red palm oil (RPO), which is a natural oil obtained from oil palm fruit (Elaeis guineensis) rich in natural fat-soluble tocopherols, tocotrienols and carot-enoids, on lipid peroxidation and endotoxemia with plasma endotoxin-inactivating capacity, proinlfammatory cytokines proifle, and monocyte tissue factor in patients with chronic liver disease. METHODS: The study group consisted of sixty patients (34 males and 26 females; mean age 62 years, range 54-75) with Child A/B, genotype 1 HCV-related cirrhosis without a history of ethanol consumption, randomly enrolled into an 8-week oral daily treatment with either vitamin E or RPO. All patients had undergone an upper gastrointestinal endoscopy 8 months before, and 13 out of them showed esophageal varices. RESULTS: Both treatments signiifcantly decreased erythro-cyte malondialdehyde and urinary isoprostane output, only RPO signiifcantly affected macrophage-colony stimulating fac-tor and monocyte tissue factor. Liver ultrasound imaging did not show any change. CONCLUSIONS: RPO beneifcially modulates oxidative stress and, not least, downregulates macrophage/monocyte inlfam-matory parameters. RPO can be safely advised as a valuable nutritional implementation tool in the management of chron-ic liver diseases.

  18. Profiling of differentially expressed chemotactic-related genes in MCP-1 treated macrophage cell line using human cDNA arrays

    Institute of Scientific and Technical Information of China (English)

    Guang-Xing Bian; Hong Miao; Lei Qiu; Dong-Mei Cao; Bao-Yu Guo

    2005-01-01

    AIM: To study the global gene expression of chemotactic genes in macrophage line U937 treated with human monocyte chemoattractant protein-1 (MCP-1) through the use of ExpreeChipTMHO2 cDNA array.METHODS: Total RNA was extracted from MCP-1 treated macrophage line U937 and normal U937 cells, reversely transcribed to cDNA, and then screened in parallel with HO2 human cDNA array chip. The scanned result was additionally validated using RT-PCR.RESULTS: The result of cDNA array showed that one chemotactic-related gene was up-regulated more than two-fold (RANTES) and seven chemotactic-related genes were down-regulated more than two-fold (CCR1, CCR5,ccl16, GROβ, GROγ, IL-8 and granulocyte chemotactic protein 2) in MCP-1 treated U937 cells at mRNA level.RT-PCR analysis of four of these differentially expressed genes gave results consistent with cDNA array findings.CONCLUSION: MCP-1 could influence some chemokine and receptor expressions in macrophages in vitro. MCP-1mainly down-regulates the expression of chemotactic genes influencing neutrophilic granulocyte expression (GROβ, GROγ, IL-8 and granulocyte chemotactic protein 2), and the mRNA level of CCR5, which plays a critical role in many disorders and illnesses.

  19. Kinetic and hydrodynamic models of chemotactic aggregation

    CERN Document Server

    Chavanis, Pierre-Henri

    2007-01-01

    We derive general kinetic and hydrodynamic models of chemotactic aggregation that describe certain features of the morphogenesis of biological colonies (like bacteria, amoebae, endothelial cells or social insects). Starting from a stochastic model defined in terms of N coupled Langevin equations, we derive a nonlinear mean field Fokker-Planck equation governing the evolution of the distribution function of the system in phase space. By taking the successive moments of this kinetic equation and using a local thermodynamic equilibrium condition, we derive a set of hydrodynamic equations involving a damping term. In the limit of small frictions, we obtain a hyperbolic model describing the formation of network patterns (filaments) and in the limit of strong frictions we obtain a parabolic model which is a generalization of the standard Keller-Segel model describing the formation of clusters (clumps). Our approach connects and generalizes several models introduced in the chemotactic literature. We discuss the anal...

  20. Spatiotemporal chemotactic model for ant foraging

    Science.gov (United States)

    Ramakrishnan, Subramanian; Laurent, Thomas; Kumar, Manish; Bertozzi, Andrea L.

    2014-12-01

    In this paper, we present a generic theoretical chemotactic model that accounts for certain emergent behaviors observed in ant foraging. The model does not have many of the constraints and limitations of existing models for ants colony dynamics and takes into account the distinctly different behaviors exhibited in nature by ant foragers in search of food and food ferrying ants. Numerical simulations based on the model show trail formation in foraging ant colonies to be an emergent phenomenon and, in particular, replicate behavior observed in experiments involving the species P. megacephala. The results have broader implications for the study of randomness in chemotactic models. Potential applications include the developments of novel algorithms for stochastic search in engineered complex systems such as robotic swarms.

  1. Self-propelled chemotactic ionic liquid droplets

    OpenAIRE

    Francis, Wayne; Fay, Cormac; Florea, Larisa; Diamond, Dermot

    2015-01-01

    Herein we report the chemotactic behaviour of self-propelled droplets composed solely of the ionic liquid trihexyl(tetradecyl)phosphonium chloride ([P6,6,6,14][Cl]). These droplets spontaneously move along an aqueous-air boundary in the direction of chloride gradients to specific destinations due to asymmetric release of [P6,6,6,14]+ cationic surfactant from the droplet into the aqueous phase.

  2. Macrophage colony-stimulating factor (CSF1) controls monocyte production and maturation and the steady-state size of the liver in pigs.

    Science.gov (United States)

    Sauter, Kristin A; Waddell, Lindsey A; Lisowski, Zofia M; Young, Rachel; Lefevre, Lucas; Davis, Gemma M; Clohisey, Sara M; McCulloch, Mary; Magowan, Elizabeth; Mabbott, Neil A; Summers, Kim M; Hume, David A

    2016-09-01

    Macrophage colony-stimulating factor (CSF1) is an essential growth and differentiation factor for cells of the macrophage lineage. To explore the role of CSF1 in steady-state control of monocyte production and differentiation and tissue repair, we previously developed a bioactive protein with a longer half-life in circulation by fusing pig CSF1 with the Fc region of pig IgG1a. CSF1-Fc administration to pigs expanded progenitor pools in the marrow and selectively increased monocyte numbers and their expression of the maturation marker CD163. There was a rapid increase in the size of the liver, and extensive proliferation of hepatocytes associated with increased macrophage infiltration. Despite the large influx of macrophages, there was no evidence of liver injury and no increase in circulating liver enzymes. Microarray expression profiling of livers identified increased expression of macrophage markers, i.e., cytokines such as TNF, IL1, and IL6 known to influence hepatocyte proliferation, alongside cell cycle genes. The analysis also revealed selective enrichment of genes associated with portal, as opposed to centrilobular regions, as seen in hepatic regeneration. Combined with earlier data from the mouse, this study supports the existence of a CSF1-dependent feedback loop, linking macrophages of the liver with bone marrow and blood monocytes, to mediate homeostatic control of the size of the liver. The results also provide evidence of safety and efficacy for possible clinical applications of CSF1-Fc.

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

    Science.gov (United States)

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

    2011-06-01

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

  4. Telmisartan ameliorates lipopolysaccharide-induced innate immune response through peroxisome proliferator-activated receptor-γ activation in human monocytes

    Science.gov (United States)

    Pang, Tao; Benicky, Julius; Wang, Juan; Orecna, Martina; Sanchez-Lemus, Enrique; Saavedra, Juan M.

    2011-01-01

    Objective Angiotensin II type 1 receptor (AT1) blockers (ARBs) reduce the bacterial endotoxin lipopolysaccharide (LPS)-induced innate immune response in human circulating monocytes expressing few AT1. To clarify the mechanisms of anti-inflammatory effects of ARBs with different peroxisome proliferator-activated receptor-γ (PPARγ)-activating potencies, we focused our study on telmisartan, an ARB with the highest PPARγ-stimulating activity. Methods Human circulating monocytes and monocytic THP-1 (human acute monocytic leukemia cell line) cells were exposed to 50 ng/ml LPS with or without pre-incubation with telmisartan. AT1 mRNA and protein expressions were determined by real-time PCR and membrane receptor binding assay, respectively. The expression of pro-inflammatory factors was determined by real-time PCR, western blot analysis and ELISA. PPARγ activation was measured by electrophoretic mobility shift assay and its role was determined by pharmacological inhibition and PPARγ gene silencing. Results In human monocytes, telmisartan significantly attenuated the LPS-induced expression of pro-inflammatory factors, the release of pro-inflammatory cytokines and prostaglandin E2, nuclear factor-κB activation and reactive oxygen species formation. In THP-1 cells, telmisartan significantly reduced LPS-induced tumor necrosis factor-α, inhibitor of κB-α, monocyte chemotactic protein-1 (MCP-1) and lectin-like oxidized low-density lipoprotein receptor-1 gene expression and MCP-1-directed migration. Telmisartan also stimulated the expression of the PPARγ target genes cluster of differentiation 36 and ATP-binding cassette subfamily G member 1 in monocytes. The anti-inflammatory effects of telmisartan were prevented by both PPARγ antagonism and PPARγ gene silencing. Anti-inflammatory effects of ARBs correlated with their PPARγ agonist potency. Conclusion Our observations demonstrate that in human monocytes, ARBs inhibit the LPS-induced pro-inflammatory response to a

  5. 基质细胞衍生因子-1对神经干细胞的趋化作用%The chemotactic effects of stromal cell derived factor-1 on neural stem cells

    Institute of Scientific and Technical Information of China (English)

    陈二涛; 冯东福; 潘栋超; 毕永延; 汪洋; 朱志安

    2010-01-01

    目的 观察基质细胞衍生因子-1(SDF-1)对神经干细胞(NSCs)迁移的影响.方法 由GFP转基因SD大鼠胚胎脑组织获取NSCs并进行传代培养,免疫细胞化学染色法检测SDF-1特异性受体CXCR4的表达,利用Blind-Well小室体外迁移体系观察不同浓度的SDF-1(0、1、10、50、100、500、1000μg/L)对NSCs定向迁移数量的影响,随后分别使用CXCR4激动剂和阻断剂处理NSCs,再次利用上述方法观察最适浓度SDF-1时NSCs的迁移.结果 成功分离培养得到能够稳定表达GFP的NSCs,且CXCR4在该种NSCs上有表达.体外趋化实验结果表明,SDF-1对NSCs有较强的趋化作用,随着SDF-1浓度的升高,发生迁移的细胞数量也随之增加,并于SDF-1浓度为500μg/L时达到最高峰;CXCR4特异性激动剂和阻断剂分别能够增强和减弱SDF-1对NSCs定向迁移的趋化作用.结论 SDF-1与其特异性受体CXCR4相互作用,能够对NSCs的定向迁移产生靶向性作用.%Objective To investigate the effect of stromal cell derived factor-1 ( SDF-1) on the regulation of neural stem cells (NSCs) migration. Methods NSCs were obtained from the cerebral cortex of embryonic GFP transgenic rats. After cell cultured in vitro, CXCR4, specific receptor of SDF-1, was detected by fluorescence immunocytochemistry. Using Blind-Well chambers, the chemotactic effects of SDF-1 was investigated by counting the cells which had crossed 8μm pore membrane and adhered to the superficies inferia of the membrane when confronted with varying concentrations of SDF-1α (0, 1, 10, 50, 100, 500 and 1000 μg/L) and the agonist or antagonist of CXCR4. Results Neurospheres were formed, which expressed GFP and were capable of differentiating into neurons (β-tubulin + ) and astrocytes (GFAP + ) in media without mitogens. Fluorescence immunocytochemistry showed that CXCR4 and Nestin were co-expressed in NSCs. SDF-1 showed great chemotaxis to NSCs, and the amount of cells migrating through the membrane in 500

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

    Energy Technology Data Exchange (ETDEWEB)

    Wei, Guoqian; Zhang, Xueyan; Su, Zhendong; Li, Xueqi, E-mail: xueqili075@yeah.net

    2015-01-30

    Highlights: • GA inhibited TNF-α-induced binding of monocytes to endothelial cells. • GA inhibited the induction of adhesion molecules MCP-1, VCAM-1 and E-selectin. • GA inhibits NF-κB p65 nuclear translocation and transcriptional activity. • GA inhibits TNF-α-induced IκBα degradation. - Abstract: Pro-inflammatory cytokines such as tumor necrosis factor-alpha (TNF-α) is considered to be the major one contributing to the process of development of endothelial dysfunction. Exposure to TNF-α induces the expression of a number of proinflammatory chemokines, such as monocyte chemotactic protein-1 (MCP-1), and adhesion molecules, including vascular adhesion molecule-1 (VCAM-1) and E-selectin, which mediate the interaction of invading monocytes with vascular endothelial cells. Glatiramer acetate (GA) is a licensed clinical drug for treating patients suffering from multiple sclerosis (MS). The effects of GA in vascular disease have not shown before. In this study, we found that GA significantly inhibited TNF-α-induced binding of monocytes to endothelial cells. Mechanistically, we found that GA ameliorated the upregulation of MCP-1, VCAM-1, and E-selectin induced by TNF-α. Notably, this process is mediated by inhibiting the nuclear translocation and activation of NF-κB. Our results also indicate that GA pretreatment attenuates the up-regulation of COX-2 and iNOS. These data suggest that GA might have a potential benefit in therapeutic endothelial dysfunction related diseases.

  7. Identification of a chemotactic sensitivity in a coupled system

    CERN Document Server

    Fister, K Renee

    2007-01-01

    Chemotaxis is the process by which cells behave in a way that follows the chemical gradient. Applications to bacteria growth, tissue inflammation, and vascular tumors provide a focus on optimization strategies. Experiments can characterize the form of possible chemotactic sensitivities. This paper addresses the recovery of the chemotactic sensitivity from these experiments while allowing for nonlinear dependence of the parameter on the state variables. The existence of solutions to the forward problem is analyzed. The identification of a chemotactic parameter is determined by inverse problem techniques. Tikhonov regularization is investigated and appropriate convergence results are obtained. Numerical results of concentration dependent chemotactic terms are explored.

  8. A novel approach for the generation of human dendritic cells from blood monocytes in the absence of exogenous factors.

    Science.gov (United States)

    Schanen, Brian C; Drake, Donald R

    2008-06-01

    Human dendritic cells (DCs) for research and clinical applications are typically derived from purified blood monocytes that are cultured in a cocktail of cytokines for a week or more. Because it has been suggested that these cytokine-derived DCs may be deficient in some important immunological functions and might not accurately represent antigen presenting cell (APC) populations found under normal conditions in vivo, there is an interest in developing methods that permit the derivation of DCs in a more physiologically relevant manner in vitro. Here, we describe a simple and reliable technique for generating large numbers of highly purified DCs that is based on a one-way migration of blood monocytes through a layer of human umbilical vein endothelial cells (HUVECs) that are cultured to confluency in the upper chamber of a Transwell device. The resultant APCs, harvested from the lower Transwell chamber, resemble other cultured DC populations in their expression of major histocompatibility (MHC) and costimulatory molecules, ability to phagocytose protein antigens and capacity to trigger primary antigen-specific T cell responses. This technique offers several advantages over the standard method of in vitro cytokine-driven DC development, including: (1) the rapidity of this approach, as DC differentiation occurs in only 2 days, (2) the differentiation process itself, which is more akin to the development of DCs under physiologic conditions and (3) the cost-effectiveness of the system, since no monocyte pre-selection is required and DC development occurs in the absence of expensive recombinant cytokines.

  9. Monocytes conditioned media stimulate fibronectin expression and spreading of inflammatory breast cancer cells in three-dimensional culture: A mechanism mediated by IL-8 signaling pathway

    Directory of Open Access Journals (Sweden)

    Mohamed Mona M

    2012-02-01

    Full Text Available Abstract Background Inflammatory breast cancer (IBC is the most aggressive form of breast cancer characterized by invasion of carcinoma cells into dermal lymphatic vessels where they form tumor emboli over expressing adhesion molecule E-cadherin. Although invasion and metastasis are dynamic processes controlled by complex interaction between tumor cells and microenvironment the mechanisms by which soluble mediators may regulate motility and invasion of IBC cells are poorly understood. The present study investigated the effect of media conditioned by human monocytes U937 secreted cytokines, chemokines and growth factors on the expression of adhesion molecules E-cadherin and fibronectin of human IBC cell line SUM149. Furthermore, cytokines signaling pathway involved were also identified. Results U937 secreted cytokines, chemokines and growth factors were characterized by cytokine antibody array. The major U937 secreted cytokines/chemokines were interleukin-8 (IL-8 and monocyte chemotactic protein-1 (MCP-1/CCL2. When SUM149 cells were seeded in three dimensional (3D models with media conditioned by U937 secreted cytokines, chemokines and growth factors; results showed: 1 changes in the morphology of IBC cells from epithelial to migratory spindle shape branched like structures; 2 Over-expression of adhesion molecule fibronectin and not E-cadherin. Further analysis revealed that over-expression of fibronectin may be mediated by IL-8 via PI3K/Akt signaling pathway. Conclusion The present results suggested that cytokines secreted by human monocytes may promote chemotactic migration and spreading of IBC cell lines. Results also indicated that IL-8 the major secreted cytokine by U937 cells may play essential role in fibronectin expression by SUM149 cells via interaction with IL-8 specific receptors and stimulation of PI3K/Akt signaling pathway.

  10. Monocytes-derived macrophages mediated stable expression of human brain-derived neurotrophic factor, a novel therapeutic strategy for neuroAIDS.

    Directory of Open Access Journals (Sweden)

    Jing Tong

    Full Text Available HIV-1 associated dementia remains a significant public health burden. Clinical and experimental research has shown that reduced levels of brain-derived neurotrophic factor (BDNF may be a risk factor for neurological complications associated with HIV-1 infection. We are actively testing genetically modified macrophages for their possible use as the cell-based gene delivery vehicle for the central nervous system (CNS. It can be an advantage to use the natural homing/migratory properties of monocyte-derived macrophages to deliver potentially neuroprotective BDNF into the CNS, as a non-invasive manner. Lentiviral-mediated gene transfer of human (hBDNF plasmid was constructed and characterized. Defective lentiviral stocks were generated by transient transfection of 293T cells with lentiviral transfer plasmid together with packaging and envelope plasmids. High titer lentiviral vector stocks were harvested and used to transduce human neuronal cell lines, primary cultures of human peripheral mononocyte-derived macrophages (hMDM and murine myeloid monocyte-derived macrophages (mMDM. These transduced cells were tested for hBDNF expression, stability, and neuroprotective activity. The GenomeLab GeXP Genetic Analysis System was used to evaluate transduced cells for any adverse effects by assessing gene profiles of 24 reference genes. High titer vectors were prepared for efficient transduction of neuronal cell lines, hMDM, and mMDM. Stable secretion of high levels of hBDNF was detected in supernatants of transduced cells using western blot and ELISA. The conditioned media containing hBDNF were shown to be protective to neuronal and monocytic cell lines from TNF-α and HIV-1 Tat mediated cytotoxicity. Lentiviral vector-mediated gene transduction of hMDM and mMDM resulted in high-level, stable expression of the neuroprotective factorBDNF in vitro. These findings form the basis for future research on the potential use of BDNF as a novel therapy for neuroAIDS.

  11. Monocytes-derived macrophages mediated stable expression of human brain-derived neurotrophic factor, a novel therapeutic strategy for neuroAIDS.

    Science.gov (United States)

    Tong, Jing; Buch, Shilpa; Yao, Honghong; Wu, Chengxiang; Tong, Hsin-I; Wang, Youwei; Lu, Yuanan

    2014-01-01

    HIV-1 associated dementia remains a significant public health burden. Clinical and experimental research has shown that reduced levels of brain-derived neurotrophic factor (BDNF) may be a risk factor for neurological complications associated with HIV-1 infection. We are actively testing genetically modified macrophages for their possible use as the cell-based gene delivery vehicle for the central nervous system (CNS). It can be an advantage to use the natural homing/migratory properties of monocyte-derived macrophages to deliver potentially neuroprotective BDNF into the CNS, as a non-invasive manner. Lentiviral-mediated gene transfer of human (h)BDNF plasmid was constructed and characterized. Defective lentiviral stocks were generated by transient transfection of 293T cells with lentiviral transfer plasmid together with packaging and envelope plasmids. High titer lentiviral vector stocks were harvested and used to transduce human neuronal cell lines, primary cultures of human peripheral mononocyte-derived macrophages (hMDM) and murine myeloid monocyte-derived macrophages (mMDM). These transduced cells were tested for hBDNF expression, stability, and neuroprotective activity. The GenomeLab GeXP Genetic Analysis System was used to evaluate transduced cells for any adverse effects by assessing gene profiles of 24 reference genes. High titer vectors were prepared for efficient transduction of neuronal cell lines, hMDM, and mMDM. Stable secretion of high levels of hBDNF was detected in supernatants of transduced cells using western blot and ELISA. The conditioned media containing hBDNF were shown to be protective to neuronal and monocytic cell lines from TNF-α and HIV-1 Tat mediated cytotoxicity. Lentiviral vector-mediated gene transduction of hMDM and mMDM resulted in high-level, stable expression of the neuroprotective factorBDNF in vitro. These findings form the basis for future research on the potential use of BDNF as a novel therapy for neuroAIDS.

  12. The major surface glycoprotein of Pneumocystis carinii induces release and gene expression of interleukin-8 and tumor necrosis factor alpha in monocytes

    DEFF Research Database (Denmark)

    Benfield, T L; Lundgren, Bettina; Levine, S J

    1997-01-01

    Recent studies suggest that interleukin-8 (IL-8) and tumor necrosis factor alpha (TNF-alpha) may play a central role in host defense and pathogenesis during Pneumocystis carinii pneumonia. In order to investigate whether the major surface antigen (MSG) of human P. carinii is capable of eliciting...... with 0.2 to 5 microg of MSG/ml (P protection assay, increases in steady-state mRNA levels for IL-8 and TNF......-alpha were detectable at 4 h. These data show that recognition of MSG by monocytes involves a mannose-mediated mechanism and results in the release of the proinflammatory cytokines IL-8 and TNF-alpha....

  13. Platelet-derived growth factor (PDGF-BB-mediated induction of monocyte chemoattractant protein 1 in human astrocytes: implications for HIV-associated neuroinflammation

    Directory of Open Access Journals (Sweden)

    Bethel-Brown Crystal

    2012-12-01

    Full Text Available Abstract Chemokine (C-C motif ligand 2, also known as monocyte chemoattractant protein 1 (MCP-1 is an important factor for the pathogenesis of HIV-associated neurocognitive disorders (HAND. The mechanisms of MCP-1-mediated neuropathogenesis, in part, revolve around its neuroinflammatory role and the recruitment of monocytes into the central nervous system (CNS via the disrupted blood-brain barrier (BBB. We have previously demonstrated that HIV-1/HIV-1 Tat upregulate platelet-derived growth factor (PDGF-BB, a known cerebrovascular permeant; subsequently, the present study was aimed at exploring the regulation of MCP-1 by PDGF-BB in astrocytes with implications in HAND. Specifically, the data herein demonstrate that exposure of human astrocytes to HIV-1 LAI elevated PDGF-B and MCP-1 levels. Furthermore, treating astrocytes with the human recombinant PDGF-BB protein significantly increased the production and release of MCP-1 at both the RNA and protein levels. MCP-1 induction was regulated by activation of extracellular-signal-regulated kinase (ERK1/2, c-Jun N-terminal kinase (JNK and p38 mitogen-activated protein (MAP kinases and phosphatidylinositol 3-kinase (PI3K/Akt pathways and the downstream transcription factor, nuclear factor κB (NFκB. Chromatin immunoprecipitation (ChIP assays demonstrated increased binding of NFκB to the human MCP-1 promoter following PDGF-BB exposure. Conditioned media from PDGF-BB-treated astrocytes increased monocyte transmigration through human brain microvascular endothelial cells (HBMECs, an effect that was blocked by STI-571, a tyrosine kinase inhibitor (PDGF receptor (PDGF-R blocker. PDGF-BB-mediated release of MCP-1 was critical for increased permeability in an in vitro BBB model as evidenced by blocking antibody assays. Since MCP-1 is linked to disease severity, understanding its modulation by PDGF-BB could aid in understanding the proinflammatory responses in HAND. These results suggest that astrocyte

  14. Dynamics of Chemotactic Droplets in Salt Concentration Gradients

    DEFF Research Database (Denmark)

    Cejkova, J.; Novak, M.; Stepanek, F.

    2014-01-01

    The chemotactic movement of decanol droplets in aqueous solutions of sodium decanoate in response to concentration gradients of NaCl has been investigated. Key parameters of the chemotactic response, namely the induction time and the migration velocity, have been evaluated as a function of the so...

  15. Vascular endothelial growth factor (VEGF and monocyte chemoattractant protein (MCP-1 levels unaltered in symptomatic atherosclerotic carotid plaque patients from North India

    Directory of Open Access Journals (Sweden)

    Dheeraj eKhurana

    2013-04-01

    Full Text Available We aimed to identify the role of vascular endothelial growth factor(VEGF and monocyte chemoattractant protein(MCP-1 as a serum biomarker of symptomatic carotid atherosclerotic plaque in North Indian population. Individuals with symptomatic carotid atherosclerotic plaque have high risk of ischemic stroke. Previous studies from western countries have shown an association between VEGF and MCP-1 levels and the incidence of ischemic stroke. In this study, venous blood from 110 human subjects was collected, 57 blood samples of which were obtained from patients with carotid plaques, 38 neurological controls without carotid plaques and another 15 healthy controls who had no history of serious illness. Serum VEGF and MCP-1 levels were measured using commercially available enzyme-linked immunosorbent assay(ELISA. We also correlated the data clinically and carried out risk factor analysis based on the detailed questionnaire obtained from each patient. For risk factor analysis, a total of 70 symptomatic carotid plaque cases and equal number of age and sex matched healthy controls were analyzed. We found that serum VEGF levels in carotid plaque patients did not show any significant change when compared to either of the controls. Similarly, there was no significant upregulation of monocyte chemoattractant protein-1 in the serum of these patients. The risk factor analysis revealed that hypertension, diabetes, and physical inactivity were the main correlates of carotid atherosclerosis(p<0.05. Prevalence of patients was higher residing in urban areas as compared to rural region. We also found that patients coming from mountaineer region were relatively less vulnerable to cerebral atherosclerosis as compared to the ones residing at plain region. We conclude that the pathogenesis of carotid plaques may progress independent of these inflammatory molecules. In parallel, risk factor analysis indicates hypertension, diabetes and sedentary lifestyle as the most

  16. Association of calprotectin with leukocyte chemotactic and inflammatory mediators following acute aerobic exercise.

    Science.gov (United States)

    Maharaj, Arun; Slusher, Aaron L; Zourdos, Michael C; Whitehurst, Michael; Fico, Brandon G; Huang, Chun-Jung

    2016-01-01

    The objective of this study was to examine whether acute aerobic exercise-mediated calprotectin in plasma would be associated with monocyte chemotactic protein-1 (MCP-1), myeloperoxidase (MPO), and interleukin-6 (IL-6) in healthy individuals. Eleven healthy participants, aged 18 to 30 years, were recruited to perform a 30-min bout of aerobic exercise at 75% maximal oxygen uptake. Acute aerobic exercise elicited a significant elevation across time in plasma calprotectin, MCP-1, MPO, and IL-6. Body mass index (BMI) was positively correlated with calprotectin area-under-the-curve with "respect to increase" (AUCi) and IL-6 AUCi. Furthermore, calprotectin AUCi was positively correlated with IL-6 AUCi and MPO AUCi, even after controlling for BMI. Although MPO AUCi was positively correlated with IL-6 AUCi, this relationship no longer existed after controlling for BMI. These results suggest that acute aerobic exercise could mediate innate immune response associated with calprotectin and its related leukocyte chemotactic and inflammatory mediators, especially in individuals with elevated BMI.

  17. Monocyte Subpopulations in Angiogenesis

    Science.gov (United States)

    Dalton, Heather J.; Armaiz-Pena, Guillermo; Gonzalez-Villasana, Vianey; Lopez-Berestein, Gabriel; Bar-Eli, Menashe; Sood, Anil K.

    2014-01-01

    Growing understanding of the role of the tumor microenvironment in angiogenesis has brought monocyte-derived cells into focus. Monocyte subpopulations are an increasingly attractive therapeutic target in many pathologic states, including cancer. Before monocyte-directed therapies can be fully harnessed for clinical use, understanding of monocyte-driven angiogenesis in tissue development and homeostasis, as well as malignancy, is required. Here, we provide an overview of the mechanisms by which monocytic subpopulations contribute to angiogenesis in tissue and tumor development, highlight gaps in our existing knowledge, and discuss opportunities to exploit these cells for clinical benefit. PMID:24556724

  18. The major surface glycoprotein of Pneumocystis carinii induces release and gene expression of interleukin-8 and tumor necrosis factor alpha in monocytes

    DEFF Research Database (Denmark)

    Benfield, T L; Lundgren, Bettina; Levine, S J;

    1997-01-01

    with 0.2 to 5 microg of MSG/ml (P TNF-alpha from MSG-stimulated monocytes at 20 h was inhibited by 60 and 86%, respectively, after coincubation with soluble yeast mannan (P = 0.01). With an RNase protection assay, increases in steady-state mRNA levels for IL-8 and TNF......Recent studies suggest that interleukin-8 (IL-8) and tumor necrosis factor alpha (TNF-alpha) may play a central role in host defense and pathogenesis during Pneumocystis carinii pneumonia. In order to investigate whether the major surface antigen (MSG) of human P. carinii is capable of eliciting...... the release of IL-8 and TNF-alpha, human monocytes were cultured in the presence of purified MSG. MSG-stimulated cells released significant amounts of IL-8 within 4 h, and at 20 h, cells stimulated with MSG released 45.5 +/- 9.3 ng of IL-8/ml versus 3.7 +/- 1.1 ng/ml for control cultures (P = 0...

  19. Sargaquinoic Acid Inhibits TNF-α-Induced NF-κB Signaling, Thereby Contributing to Decreased Monocyte Adhesion to Human Umbilical Vein Endothelial Cells (HUVECs).

    Science.gov (United States)

    Gwon, Wi-Gyeong; Lee, Bonggi; Joung, Eun-Ji; Choi, Min-Woo; Yoon, Nayoung; Shin, Taisun; Oh, Chul-Woong; Kim, Hyeung-Rak

    2015-10-21

    Sargaquinoic acid (SQA) has been known for its antioxidant and anti-inflammatory properties. This study investigated the effects of SQA isolated from Sargassum serratifolium on the inhibition of tumor necrosis factor (TNF)-α-induced monocyte adhesion to human umbilical vein endothelial cells (HUVECs). SQA decreased the expression of cell adhesion molecules such as intracellular adhesion molecule-1 and vascular cell adhesion molecule-1 as well as chemotactic cytokines such as interleukin-8 and monocyte chemoattractant protein-1 in TNF-α-treated HUVECs. As a result, SQA prevented monocyte adhesion to TNF-α-induced adhesion. SQA also inhibited TNF-α-induced nuclear factor kappa B (NF-κB) translocation into the nucleus by preventing proteolytic degradation of inhibitor κB-α. Overall, SQA protects against TNF-α-induced vascular inflammation through inhibition of the NF-κB pathway in HUVECs. These data suggest that SQA may be used as a therapeutic agent for vascular inflammatory diseases such as atherosclerosis.

  20. 5-(3′,4′-Dihydroxyphenyl-γ-valerolactone), a Major Microbial Metabolite of Proanthocyanidin, Attenuates THP-1 Monocyte-Endothelial Adhesion

    Science.gov (United States)

    Han, Seung Min; Yoon Park, Jung Han; Lee, Ki Won; Lee, Chang Yong

    2017-01-01

    Several metabolomics of polymeric flavan-3-ols have reported that proanthocyanidins are extensively metabolized by gut microbiota. 5-(3′,4′-dihydroxyphenyl)-γ-valerolactone (DHPV) has been reported to be the major microbial metabolite of proanthocyanidins. We demonstrated that DHPV has stronger prevention effect on tumor necrosis factor (TNF)-α-stimulated adhesion of THP-1 human monocytic cells to human umbilical vein endothelial cells compared to its potential precursors such as procyanidin A1, A2, B1 and B2, (+)catechin, (−)epicatechin and its microbial metabolites such as 3-(3,4-dihydroxyphenyl)propionic acid and 2-(3,4-dihydroxyphenyl)acetic acid. Mechanism study showed that DHPV prevents THP-1 monocyte-endothelial cell adhesion by downregulating TNF-α-stimulated expressions of the two biomarkers of atherosclerosis such as vascular cell adhesion molecule-1 and monocyte chemotactic protein-1, activation of nuclear factor kappa B transcription and phosphorylation of I kappa-B kinase and IκBα. We suggested that DHPV has higher potentiality in prevention of atherosclerosis among the proanthocyanidin metabolites. PMID:28672844

  1. Aortic endothelial cells regulate proliferation of human monocytes in vitro via a mechanism synergistic with macrophage colony-stimulating factor. Convergence at the cyclin E/p27(Kip1) regulatory checkpoint.

    Science.gov (United States)

    Antonov, A S; Munn, D H; Kolodgie, F D; Virmani, R; Gerrity, R G

    1997-06-15

    Monocyte-derived macrophages (Mphis) are pivotal participants in the pathogenesis of atherosclerosis. Evidence from both animal and human plaques indicates that local proliferation may contribute to accumulation of lesion Mphis, and the major Mphi growth factor, macrophage colony stimulating factor (MCSF), is present in atherosclerotic plaques. However, most in vitro studies have failed to demonstrate that human monocytes/Mphis possess significant proliferative capacity. We now report that, although human monocytes cultured in isolation showed only limited MCSF-induced proliferation, monocytes cocultured with aortic endothelial cells at identical MCSF concentrations underwent enhanced (up to 40-fold) and prolonged (21 d) proliferation. In contrast with monocytes in isolation, this was optimal at low seeding densities, required endothelial cell contact, and could not be reproduced by coculture with smooth muscle cells. Intimal Mphi isolated from human aortas likewise showed endothelial cell contact-dependent, MCSF-induced proliferation. Consistent with a two-signal mechanism governing Mphi proliferation, the cell cycle regulatory protein, cyclin E, was rapidly upregulated by endothelial cell contact in an MCSFindependent fashion, but MCSF was required for successful downregulation of the cell cycle inhibitory protein p27(Kip1) before cell cycling. Thus endothelial cells and MCSF differentially and synergistically regulate two Mphi genes critical for progression through the cell cycle.

  2. Strenuous physical exercise adversely affects monocyte chemotaxis

    DEFF Research Database (Denmark)

    Czepluch, Frauke S; Barres, Romain; Caidahl, Kenneth

    2011-01-01

    Physical exercise is important for proper cardiovascular function and disease prevention, but it may influence the immune system. We evaluated the effect of strenuous exercise on monocyte chemotaxis. Monocytes were isolated from blood of 13 young, healthy, sedentary individuals participating...... in a three-week training program which consisted of repeated exercise bouts. Monocyte chemotaxis and serological biomarkers were investigated at baseline, after three weeks training and after four weeks recovery. Chemotaxis towards vascular endothelial growth factor-A (VEGF-A) and transforming growth factor...

  3. The major surface glycoprotein of Pneumocystis carinii induces release and gene expression of interleukin-8 and tumor necrosis factor alpha in monocytes

    DEFF Research Database (Denmark)

    Benfield, T L; Lundgren, Bettina; Levine, S J

    1997-01-01

    Recent studies suggest that interleukin-8 (IL-8) and tumor necrosis factor alpha (TNF-alpha) may play a central role in host defense and pathogenesis during Pneumocystis carinii pneumonia. In order to investigate whether the major surface antigen (MSG) of human P. carinii is capable of eliciting...... the release of IL-8 and TNF-alpha, human monocytes were cultured in the presence of purified MSG. MSG-stimulated cells released significant amounts of IL-8 within 4 h, and at 20 h, cells stimulated with MSG released 45.5 +/- 9.3 ng of IL-8/ml versus 3.7 +/- 1.1 ng/ml for control cultures (P = 0...... with 0.2 to 5 microg of MSG/ml (P

  4. Cis and trans acting factors involved in human cytomegalovirus experimental and natural latent infection of CD14 (+ monocytes and CD34 (+ cells.

    Directory of Open Access Journals (Sweden)

    Cyprian C Rossetto

    Full Text Available The parameters involved in human cytomegalovirus (HCMV latent infection in CD14 (+ and CD34 (+ cells remain poorly identified. Using next generation sequencing we deduced the transcriptome of HCMV latently infected CD14 (+ and CD34 (+ cells in experimental as well as natural latency settings. The gene expression profile from natural infection in HCMV seropositive donors closely matched experimental latency models, and included two long non-coding RNAs (lncRNAs, RNA4.9 and RNA2.7 as well as the mRNAs encoding replication factors UL84 and UL44. Chromatin immunoprecipitation assays on experimentally infected CD14 (+ monocytes followed by next generation sequencing (ChIP-Seq were employed to demonstrate both UL84 and UL44 proteins interacted with the latent viral genome and overlapped at 5 of the 8 loci identified. RNA4.9 interacts with components of the polycomb repression complex (PRC as well as with the MIE promoter region where the enrichment of the repressive H3K27me3 mark suggests that this lncRNA represses transcription. Formaldehyde Assisted Isolation of Regulatory Elements (FAIRE, which identifies nucleosome-depleted viral DNA, was used to confirm that latent mRNAs were associated with actively transcribed, FAIRE analysis also showed that the terminal repeat (TR region of the latent viral genome is depleted of nucleosomes suggesting that this region may contain an element mediating viral genome maintenance. ChIP assays show that the viral TR region interacts with factors associated with the pre replication complex and a plasmid subclone containing the HCMV TR element persisted in latently infected CD14 (+ monocytes, strongly suggesting that the TR region mediates viral chromosome maintenance.

  5. Plasmin is a potent and specific chemoattractant for human peripheral monocytes acting via a cyclic guanosine monophosphate-dependent pathway.

    Science.gov (United States)

    Syrovets, T; Tippler, B; Rieks, M; Simmet, T

    1997-06-15

    We have previously reported that the serine protease plasmin generated during contact activation of human plasma triggers biosynthesis of leukotrienes (LTs) in human peripheral monocytes (PMs), but not in polymorphonuclear neutrophils (PMNs). We now show that purified plasmin acts as a potent chemoattractant on human monocytes, but not on PMNs. Human plasmin or plasminogen activated with urokinase, but not active site-blocked plasmin or plasminogen, elicited monocyte migration across polycarbonate membranes. Similarly, stimulation of monocytes with plasmin, but not with active site-blocked plasmin or plasminogen, induced actin polymerization. As assessed by checkerboard analysis, the plasmin-mediated monocyte locomotion was a true chemotaxis. The plasmin-induced chemotactic response was inhibited by the lysine analog trans-4-(aminomethyl)cyclohexane-1-carboxylic acid (t-AMCA), which prevents binding of plasmin/ogen to the appropriate membrane binding sites. In addition, active site-blocked plasmin inhibited monocyte migration triggered by active plasmin. Further, plasmin-induced monocyte chemotaxis was inhibited by pertussis toxin (PTX) and 1-O-hexadecyl-2-O-methyl-rac-glycerol (HMG) and chelerythrine, two structurally unrelated inhibitors of protein kinase C (PKC). Plasmin, but not active site-blocked plasmin or plasminogen, triggered formation of cyclic guanosine monophosphate (cGMP) in monocytes. LY83583, an inhibitor of soluble guanylyl cyclase, inhibited both plasmin-induced cGMP formation and the chemotactic response. The latter effect could be antagonized by 8-bromo-cGMP. In addition, KT5823 and (Rp)-8-(p-chlorophenylthio)guanosine-3',5'-cyclic monophosphorothioate [(Rp)-8-pCPT-cGMPs], two structurally unrelated inhibitors of cGMP-dependent protein kinase, inhibited plasmin-mediated monocyte chemotaxis. Thus, beyond being a stimulus for lipid mediator release, plasmin is a potent and specific chemoattractant for human monocytes acting via a c

  6. Monocyte chemotactic protein-1 and other inflammatory parameters in Bernese Mountain dogs with disseminated histiocytic sarcoma

    DEFF Research Database (Denmark)

    Nielsen, Lise Nikolic; Kjelgaard-Hansen, Mads; Kristensen, Annemarie Thuri

    2013-01-01

    The interaction between cancer and the immune system, and the production of cytokines by the tumour itself have been associated with altered levels of cytokines in human cancer patients. Bernese Mountain dogs with disseminated histiocytic sarcoma (DHS) show vague and non-specific clinical signs....... Although histiocytes can secrete cytokines in response to inflammatory stimuli, serum cytokine concentrations in dogs with DHS have not previously been investigated. The aim of this study was to evaluate the immunological state of untreated Bernese Mountain dogs with DHS by assessing multiple serum...... cytokines and to correlate these with other inflammatory markers. As a prospective case control study, 17 Bernese Mountain dogs with DHS were included along with 18 healthy controls (12 Bernese Mountain dogs and 6 dogs of various breeds). Blood samples were examined for fibrinogen, C-reactive protein (CRP...

  7. Suppression of blood monocyte and neutrophil chemotaxis in acute human malaria

    DEFF Research Database (Denmark)

    Nielsen, H; Kharazmi, A; Theander, T G

    1986-01-01

    The host response to Plasmodia includes the production of enlarged populations of peripheral blood monocytes and tissue macrophages in the spleen and the liver. Since the hyperplasia of the mononuclear phagocyte system is believed to arise as a consequence of an enhanced blood monocyte influx, we....... In conclusion, not all cell functions were altered in concert, and the previously unreported suppression of chemotactic migration might reflect a change in blood leucocyte subpopulations, deactivation in vivo or a direct suppressive effect of plasmodia induced products....

  8. Graft monocytic myeloid-derived suppressor cell content predicts the risk of acute graft-versus-host disease after allogeneic transplantation of granulocyte colony-stimulating factor-mobilized peripheral blood stem cells.

    Science.gov (United States)

    Vendramin, Antonio; Gimondi, Silvia; Bermema, Anisa; Longoni, Paolo; Rizzitano, Sara; Corradini, Paolo; Carniti, Cristiana

    2014-12-01

    Myeloid-derived suppressor cells (MDSCs) are powerful immunomodulatory cells that in mice play a role in infectious and inflammatory disorders, including acute graft-versus-host disease (GVHD) after allogeneic hematopoietic stem cell transplantation. Their relevance in clinical acute GVHD is poorly known. We analyzed whether granulocyte colony-stimulating factor (G-CSF) administration, used to mobilize hematopoietic stem cells, affected the frequency of MDSCs in the peripheral blood stem cell grafts of 60 unrelated donors. In addition, we evaluated whether the MDSC content in the peripheral blood stem cell grafts affected the occurrence of acute GVHD in patients undergoing unrelated donor allogeneic stem cell transplantation. Systemic treatment with G-CSF induces an expansion of myeloid cells displaying the phenotype of monocytic MDSCs (Lin(low/neg)HLA-DR(-)CD11b(+)CD33(+)CD14(+)) with the ability to suppress alloreactive T cells in vitro, therefore meeting the definition of MDSCs. Monocytic MDSC dose was the only graft parameter to predict acute GVHD. The cumulative incidence of acute GVHD at 180 days after transplantation for recipients receiving monocytic MDSC doses below and above the median was 63% and 22%, respectively (P = .02). The number of monocytic MDSCs infused did not impact the relapse rate or the transplant-related mortality rate (P > .05). Although further prospective studies involving larger sample size are needed to validate the exact monocytic MDSC graft dose that protects from acute GVHD, our results strongly suggest the modulation of G-CSF might be used to affect monocytic MDSCs graft cell doses for prevention of acute GVHD.

  9. Polymorphonuclear neutrophil granulocyte chemotactic hyperresponsiveness in a case of canine acromegaly.

    Science.gov (United States)

    Jensen, A L; Thomsen, M K; Aaes, H; Andreasen, M; Søndergaard, J

    1993-08-01

    Growth hormone (GH) has recently been shown to affect polymorphonuclear neutrophil granulocyte (PMN) function and to be secreted by mononuclear cells, indicating that the hormone may be active in an immunophysiologic network, acting as an endo- or paracrine priming agent. The purpose of the present study was to evaluate the chemotactic responsiveness of canine peripheral PMN in a dog with acromegaly, caused by spontaneous, progesterone-induced hypersecretion of GH and, secondary to this, a seven-fold increase in insulin-like growth factor I (IGF-I). The chemotactic responsiveness towards zymosan-activated serum (ZAS) and leukotriene B4 (LTB4) was evaluated at a time when the dog suffered from acromegaly and again 57 days after corrective surgery (ovariohysterectomy). The experiments showed that PMN from the patient exhibited enhanced chemotactic migration that appeared to be associated with the hypersomatotropic condition as judged from the reversibility of the phenomenon. The glucose intolerance and elevated serum alkaline phosphatase that were observed in the acromegalic dog were also shown to be reversible following surgery.

  10. Automated Chemotactic Sorting and Single-cell Cultivation of Microbes using Droplet Microfluidics

    Science.gov (United States)

    Dong, Libing; Chen, Dong-Wei; Liu, Shuang-Jiang; Du, Wenbin

    2016-04-01

    We report a microfluidic device for automated sorting and cultivation of chemotactic microbes from pure cultures or mixtures. The device consists of two parts: in the first part, a concentration gradient of the chemoeffector was built across the channel for inducing chemotaxis of motile cells; in the second part, chemotactic cells from the sample were separated, and mixed with culture media to form nanoliter droplets for encapsulation, cultivation, enumeration, and recovery of single cells. Chemotactic responses were assessed by imaging and statistical analysis of droplets based on Poisson distribution. An automated procedure was developed for rapid enumeration of droplets with cell growth, following with scale-up cultivation on agar plates. The performance of the device was evaluated by the chemotaxis assays of Escherichia coli (E. coli) RP437 and E. coli RP1616. Moreover, enrichment and isolation of non-labelled Comamonas testosteroni CNB-1 from its 1:10 mixture with E. coli RP437 was demonstrated. The enrichment factor reached 36.7 for CNB-1, based on its distinctive chemotaxis toward 4-hydroxybenzoic acid. We believe that this device can be widely used in chemotaxis studies without necessarily relying on fluorescent labelling, and isolation of functional microbial species from various environments.

  11. Looking for predictive factors of clinical response to adsorptive granulocyte and monocyte apheresis in patients with ulcerative colitis: markers of response to GMA

    Directory of Open Access Journals (Sweden)

    Yokoyama Yoko

    2013-02-01

    Full Text Available Abstract Background Adsorptive granulocyte and monocyte apheresis (GMA with an Adacolumn in patients with ulcerative colitis (UC has been applied as a non-pharmacological treatment strategy, but the efficacy has been encouraging as well as discouraging, depending on patients’ demography at entry. In this study, we looked for predictive factors for clinical response to GMA in patients with UC. Methods In a retrospective setting, 43 outpatients who had been treated with GMA for active UC were evaluated. Patients were divided into remission group and non-remission group based on Lichtiger’s clinical activity index (CAI before and after 10, once a week GMA sessions. The efficacy was analysed in relation to patients’ demographic variables. To determine predictive factors that closely related to the response to GMA, receiver operating characteristic (ROC curve, and multiple logistic regression analyses were applied. Results After 10 GMA sessions, the overall clinical remission rate (CAI  Conclusions In this study, patients with a short duration of UC and low cumulative PSL dose seemed to respond well to GMA. However, we found that the best responders were patients who received GMA immediately after a clinical relapse. Additionally, GMA was effective in patients with low WBC count at the first GMA session. The findings of this study should spare medical cost and reduce morbidity time for many patients, relevant for decision making in clinical settings.

  12. Endothelial progenitor cells (CD34+KDR+) and monocytes may provide the development of good coronary collaterals despite the vascular risk factors and extensive atherosclerosis.

    Science.gov (United States)

    Kocaman, Sinan Altan; Yalçın, Mehmet Rıdvan; Yağcı, Münci; Sahinarslan, Asife; Türkoğlu, Sedat; Arslan, Uğur; Kurşunluoğlu, Nevruz; Ozdemir, Murat; Timurkaynak, Timur; Cemri, Mustafa; Abacı, Adnan; Boyacı, Bülent; Cengel, Atiye

    2011-06-01

    CD34-KDR- cell subpopulation within monocyte gate (514±173 mm(-3)) reached to highest counts in good collateral group among all study population. Endothelial progenitor cells can be mobilized from bone marrow to induce the coronary collateral growth in case of myocardial ischemia even in presence of the vascular risk factors and extensive atherosclerosis. This finding may be supportive to investigate the molecules, which can specifically mobilize EPC without inflammatory cells.

  13. Fli-1 transcription factor affects glomerulonephritis development by regulating expression of monocyte chemoattractant protein-1 in endothelial cells in the kidney.

    Science.gov (United States)

    Suzuki, Eiji; Karam, Eva; Williams, Sarah; Watson, Dennis K; Gilkeson, Gary; Zhang, Xian K

    2012-12-01

    Expression of transcription factor Fli-1 is implicated in the development of glomerulonephritis. Fli-1 heterozygous knockout (Fli1(+/-)) NZM2410 mice, a murine model of lupus, had significantly improved survival and reduced glomerulonephritis. In this study, we found that infiltrated inflammatory cells were significantly decreased in the kidneys from Fli-1(+/-) NZM2410 mice. The expression of monocyte chemoattractant protein-1 (MCP-1) was significantly decreased in kidneys from Fli-1(+/-) NZM2410 mice. The primary endothelial cells isolated from the kidneys of Fli-1(+/-) NZM2410 mice produced significantly less MCP-1. In endothelial cells transfected with specific Fli-1 siRNA the production of MCP-1 was significantly reduced compared to cells transfected with negative control siRNA. By Chromatin Immunoprecipitation (ChIP) assay, we further demonstrated that Fli-1 directly binds to the promoter of the MCP-1 gene. Our data indicate that Fli-1 impacts glomerulonephritis development by regulating expression of inflammatory chemokine MCP-1 and inflammatory cell infiltration in the kidneys in the NZM2410 mice. Published by Elsevier Inc.

  14. Circulating CD14+ monocytes in patients with aortic stenosis

    Institute of Scientific and Technical Information of China (English)

    Sara Shimoni; Valery Meledin; Iris Bar; Jacob Fabricant; Gera Gandelman; Jacob George

    2016-01-01

    BackgroundCalcific aortic stenosis (AS) is an active process sharing similarities with atherosclerosis and chronic inflammation. The pathophysiology of AS is notable for three cardinal components: inflammation, fibrosis and calcification. Monocytes play a role in each of these processes. The role of circulating monocytes in AS is not clear. The aim of the present study was to study an association between cir-culating apoptotic and non apoptotic CD14+ monocytes and AS features.MethodsWe assessed the number of CD14+ monocytes and apoptotic monocytes in 54 patients with significant AS (aortic valve area 0.74 ± 0.27 cm2) and compared them to 33 patients with similar risk factors and no valvular disease. The level of CD14+ monocytes and apoptotic monocytes was assessed by flow cytometry.ResultsThere was no difference in the risk factor profile and known coronary or peripheral vascular diseases between patients with AS and controls.Pa-tients with AS exhibited increased numbers of CD14+ monocytes as compared to controls (9.9% ± 4.9%vs. 7.7% ± 3.9%,P= 0.03). CD14+ monocyte number was related to age and the presence and severity of AS. In patients with AS, both CD14+ monocytes and apoptotic mono-cytes were inversely related to aortic valve area.ConclusionsPatients with significant AS have increased number of circulating CD14+ monocytes and there is an inverse correlation between monocyte count and aortic valve area. These findings may suggest that inflammation is operative not only in early valve injury phase, but also at later developed stages such as calcification when AS is severe.

  15. Differential expression of HIV-1 interfering factors in monocyte-derived macrophages stimulated with polarizing cytokines or interferons

    Science.gov (United States)

    Jiménez, Viviana Cobos; Booiman, Thijs; de Taeye, Steven W.; van Dort, Karel A.; Rits, Maarten A. N.; Hamann, Jörg; Kootstra, Neeltje A.

    2012-10-01

    HIV-1 replication in macrophages can be regulated by cytokines and infection is restricted in macrophages activated by type I interferons and polarizing cytokines. Here, we observed that the expression levels of the cellular factors Trim5α, CypA, APOBEC3G, SAMHD-1, Trim22, tetherin and TREX-1, and the anti-HIV miRNAs miR-28, miR-150, miR-223 and miR-382 was upregulated by IFN-α and IFN-β in macrophages, which may account for the inhibiting effect on viral replication and the antiviral state of these cells. Expression of these factors was also increased by IFN-γ +/- TNF-α, albeit to a lesser extent; yet, HIV-1 replication in these cells was not restricted at the level of proviral synthesis, indicating that these cellular factors only partially contribute to the observed restriction. IL-4, IL-10 or IL-32 polarization did not affect the expression of cellular factors and miRNAs, suggesting only a limited role for these cellular factors in restricting HIV-1 replication in macrophages.

  16. CSF Biomarkers of Monocyte Activation and Chemotaxis correlate with Magnetic Resonance Spectroscopy Metabolites during Chronic HIV Disease

    Science.gov (United States)

    Anderson, Albert M.; Fennema-Notestine, Christine; Umlauf, Anya; Taylor, Michael J.; Clifford, David B.; Marra, Christina M.; Collier, Ann C.; Gelman, Benjamin B.; McArthur, Justin C.; McCutchan, J. Allen; Simpson, David M.; Morgello, Susan; Grant, Igor; Letendre, Scott L.

    2015-01-01

    Background HIV-associated neurocognitive disorders (HAND) persist despite combination antiretroviral therapy (cART), supporting the need to better understand HIV neuropathogenesis. Magnetic resonance spectroscopy (MRS) of the brain has demonstrated abnormalities in HIV-infected individuals despite cART. We examined the associations between MRS metabolites and selected cerebrospinal fluid (CSF) biomarkers reflecting monocyte/macrophage activation and chemotaxis. Methods A multicenter cross-sectional study involving five sites in the United States was conducted. The following CSF biomarkers were measured: soluble CD14 (sCD14), monocyte chemotactic protein 1 (MCP-1), interferon inducible protein 10 (IP-10), and stromal cell derived growth factor 1 alpha (SDF-1α). The following MRS metabolites were measured from basal ganglia (BG), frontal white matter (FWM) and frontal gray matter (FGM): N-acetyl-aspartate (NAA), Myo-inositol (MI), Choline (Cho), and Creatine (Cr). CSF biomarkers were compared to absolute MRS metabolites as well as metabolite/Cr ratios using linear regression. Results 83 HIV-infected individuals were included, 78% on cART and 37% with HAND. The most robust positive correlations were between MCP-1 and Cho in BG (R2 0.179, p<0.001) as well as MCP-1 and MI in FWM (R2 0.137, p=0.002). Higher Cr levels in FWM were associated with MCP-1 (R2 0. 075, p=0.01) and IP-10 (R2 0.106, p=0.003). Comparing biomarkers to MRS metabolite/Cr ratios impacted some relationships, e.g., higher sCD14 levels were associated with lower Cho/Cr ratios in FGM (R2 0.224, p<0.001), although higher MCP-1 levels remained associated with Cho/Cr in BG. Conclusion These findings provide evidence that monocyte activation and chemotaxis continue to contribute to HIV-associated brain abnormalities in cART-treated individuals. PMID:26069183

  17. A unique anti-CD115 monoclonal antibody which inhibits osteolysis and skews human monocyte differentiation from M2-polarized macrophages toward dendritic cells.

    Science.gov (United States)

    Haegel, Hélène; Thioudellet, Christine; Hallet, Rémy; Geist, Michel; Menguy, Thierry; Le Pogam, Fabrice; Marchand, Jean-Baptiste; Toh, Myew-Ling; Duong, Vanessa; Calcei, Alexandre; Settelen, Nathalie; Preville, Xavier; Hennequi, Marie; Grellier, Benoit; Ancian, Philippe; Rissanen, Jukka; Clayette, Pascal; Guillen, Christine; Rooke, Ronald; Bonnefoy, Jean-Yves

    2013-01-01

    Cancer progression has been associated with the presence of tumor-associated M2-macrophages (M2-TAMs) able to inhibit anti-tumor immune responses. It is also often associated with metastasis-induced bone destruction mediated by osteoclasts. Both cell types are controlled by the CD115 (CSF-1R)/colony-stimulating factor-1 (CSF-1, M-CSF) pathway, making CD115 a promising target for cancer therapy. Anti-human CD115 monoclonal antibodies (mAbs) that inhibit the receptor function have been generated in a number of laboratories. These mAbs compete with CSF-1 binding to CD115, dramatically affecting monocyte survival and preventing osteoclast and macrophage differentiation, but they also block CD115/CSF-1 internalization and degradation, which could lead to potent rebound CSF-1 effects in patients after mAb treatment has ended. We thus generated and selected a non-ligand competitive anti-CD115 mAb that exerts only partial inhibitory effects on CD115 signaling without blocking the internalization or the degradation of the CD115/CSF-1 complex. This mAb, H27K15, affects monocyte survival only minimally, but downregulates osteoclast differentiation and activity. Importantly, it inhibits monocyte differentiation to CD163(+)CD64(+) M2-polarized suppressor macrophages, skewing their differentiation toward CD14(-)CD1a(+) dendritic cells (DCs). In line with this observation, H27K15 also drastically inhibits monocyte chemotactic protein-1 secretion and reduces interleukin-6 production; these two molecules are known to be involved in M2-macrophage recruitment. Thus, the non-depleting mAb H27K15 is a promising anti-tumor candidate, able to inhibit osteoclast differentiation, likely decreasing metastasis-induced osteolysis, and able to prevent M2 polarization of TAMs while inducing DCs, hence contributing to the creation of more efficient anti-tumor immune responses.

  18. Alveolar macrophage-epithelial cell interaction following exposure to atmospheric particles induces the release of mediators involved in monocyte mobilization and recruitment

    Directory of Open Access Journals (Sweden)

    Mukae Hiroshi

    2005-08-01

    Full Text Available Abstract Background Studies from our laboratory have shown that human alveolar macrophages (AM and bronchial epithelial cells (HBEC exposed to ambient particles (PM10 in vitro increase their production of inflammatory mediators and that supernatants from PM10-exposed cells shorten the transit time of monocytes through the bone marrow and promote their release into the circulation. Methods The present study concerns co-culture of AM and HBEC exposed to PM10 (EHC-93 and the production of mediators involved in monocyte kinetics measured at both the mRNA and protein levels. The experiments were also designed to determine the role of the adhesive interaction between these cells via the intercellular adhesion molecule (ICAM-1 in the production of these mediators. Results AM/HBEC co-cultures exposed to 100 μg/ml of PM10 for 2 or 24 h increased their levels of granulocyte-macrophage colony-stimulating factor (GM-CSF, M-CSF, macrophage inflammatory protein (MIP-1β, monocyte chemotactic protein (MCP-1, interleukin (IL-6 and ICAM-1 mRNA, compared to exposed AM or HBEC mono-cultures, or control non-exposed co-cultures. The levels of GM-CSF, M-CSF, MIP-1β and IL-6 increased in co-cultured supernatants collected after 24 h exposure compared to control cells (p 10-induced increase in co-culture mRNA expression. Conclusion We conclude that an ICAM-1 independent interaction between AM and HBEC, lung cells that process inhaled particles, increases the production and release of mediators that enhance bone marrow turnover of monocytes and their recruitment into tissues. We speculate that this interaction amplifies PM10-induced lung inflammation and contributes to both the pulmonary and systemic morbidity associated with exposure to air pollution.

  19. A matrix of cholesterol crystals, but not cholesterol alone, primes human monocytes/macrophages for excessive endotoxin-induced production of tumor necrosis factor-alpha. Role in atherosclerotic inflammation?

    DEFF Research Database (Denmark)

    Bendtzen, Klaus; Christensen, Ole; Nielsen, Claus Henrik

    2014-01-01

    When exposed to small amounts of bacterial endotoxin, matrices of cholesterol crystals, but not cholesterol itself, primed human monocytes/macrophages to a highly augmented (>10-fold) production of inflammatory tumor necrosis factor-α. Priming also sensitized the cells, as 10- to 100-fold lower...... suggest that cholesterol matrix formation may play a pathogenic role in atherosclerotic inflammation, and they indicate a mechanism by which bacteria and/or bacterial products may play a role in processes leading to arteriosclerosis....

  20. Hypoxia-inducible factor-1 (HIF-1) is involved in the regulation of hypoxia-stimulated expression of monocyte chemoattractant protein-1 (MCP-1/CCL2) and MCP-5 (Ccl12) in astrocytes

    OpenAIRE

    Mojsilovic-Petrovic Jelena; Callaghan Debbie; Cui Hong; Dean Clare; Stanimirovic Danica B; Zhang Wandong

    2007-01-01

    Abstract Background Neuroinflammation has been implicated in various brain pathologies characterized by hypoxia and ischemia. Astroglia play an important role in the initiation and propagation of hypoxia/ischemia-induced inflammation by secreting inflammatory chemokines that attract neutrophils and monocytes into the brain. However, triggers of chemokine up-regulation by hypoxia/ischemia in these cells are poorly understood. Hypoxia-inducible factor-1 (HIF-1) is a dimeric transcriptional fact...

  1. Pharmacological effects of mitraphylline from Uncaria tomentosa in primary human monocytes: Skew toward M2 macrophages.

    Science.gov (United States)

    Montserrat-de la Paz, S; de la Puerta, R; Fernandez-Arche, A; Quilez, A M; Muriana, F J G; Garcia-Gimenez, M D; Bermudez, B

    2015-07-21

    Uncaria tomentosa (Willdenow ex Roemer & Schultes) DC. (Rubiaceae) is a Peruvian thorny liana, commonly known as "cat׳s claw", and traditionally used in folk medicine to deal with several inflammatory diseases. Mitraphylline (MTP) is the most abundant pentacyclic oxindolic alkaloid (POA) from U. Tomentosa and has been reported to modify the inflammatory response. Herein, we have sought to identify the mechanisms underlying this modulatory effect of MTP on primary human monocytes and its ability to regulate differentiation processes on human primary monocyte and monocyte-derived macrophages. In vitro studies with human primary monocytes and monocyte-derived macrophages were performed. Monocytes and M0 macrophages were exposed to MTP (25μM) and LPS (100ng/mL). M0 macrophages were polarized to M1 and M2 phenotypes in the absence or presence of MTP. The activation state of monocytes/macrophages was assessed by flow cytometry, gene expression and protein analysis of different specific markers. In human primary monocytes, the incubation of MTP for 24h reduced the number of classical (CD14(++)CD16(-)) and intermediate (CD14(++)CD16(+)) subsets when compared to untreated or LPS-treated cells. MTP also reduced the chemotactic capacity of human primary monocytes. In addition, MTP promoted the polarization of M0 macrophages toward an anti-inflammatory M2 phenotype, the abrogation of the release of pro-inflammatory cytokines such as TNFα, IL-6 or IL-1β, as well as the restoration of markers for M2 macrophages in LPS-treated M1 macrophages. Our results suggest that MTP may be a key modulator for regulating the plasticity of monocytes/macrophages and the attenuation of the inflammatory response. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  2. Hyperhomocysteinemia-Induced Monocyte Chemoattractant Protein-1 Promoter DNA Methylation by Nuclear Factor-κB/DNA Methyltransferase 1 in Apolipoprotein E-Deficient Mice.

    Science.gov (United States)

    Wang, Ju; Jiang, Yideng; Yang, Anning; Sun, Weiwei; Ma, Changjian; Ma, Shengchao; Gong, Huihui; Shi, Yingkang; Wei, Jun

    2013-04-01

    Hyperhomocysteinemia is considered to be a significant risk factor in atherosclerosis and plays an important role in it. The purpose of this study was to determine the molecular mechanism of blood monocyte chemoattractant protein-1 (MCP-1) promoter DNA hypomethylation in the formation of atherosclerosis induced by hyperhomocysteinemia, and to explore the effect of nuclear factor-κB (NF-κB)/DNA methyltransferase 1 (DNMT1) in this mechanism. The atherosclerotic effect of MCP-1 in apolipoprotein E-deficient (ApoE(-/-)) and wild-type C57BL/6J mice was evaluated using atherosclerotic lesion area; serum NF-κB, MCP-1, and DNMT1 levels; and MCP-1 promoter DNA methylation expression. In vitro, the mechanism responsible for the effect of NF-κB/DNMT1 on foam cells was investigated by measuring NF-κB and DNMT1 levels to determine whether NF-κB/DNMT1 had an effect on gene expression. Compared with the control group, atherosclerotic lesions in ApoE(-/-) mice fed a high methionine diet significantly increased, as did the expression of MCP-1. In vitro study showed that pyrrolidine dithiocarbamate treatment down-regulated levels of NF-κB and raised DNMT1 concentrations, confirming the effect of NF-κB/DNMT1 in the MCP-1 promoter DNA methylation process. In conclusion, our results suggest that through NF-κB/DNMT1, MCP-1 promoter DNA hypomethylation may play a key role in formation of atherosclerosis under hyperhomocysteinemia.

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

    Directory of Open Access Journals (Sweden)

    Supanat Worawichawong

    2016-12-01

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

  4. Sensory Adaptation of Dictyostelium discoideum Cells to Chemotactic Signals

    NARCIS (Netherlands)

    Haastert, Peter J.M. van

    1983-01-01

    Postvegetative Dictyostelium discoideum cells react chemotactically to gradients of cAMP, folic acid, and pterin. In the presence of a constant concentration of 10-5 M cAMP cells move at random. They still are able to respond to superimposed gradients of cAMP, although the response is less efficient

  5. Plasma L-cystine/L-glutamate imbalance increases tumor necrosis factor-alpha from CD14+ circulating monocytes in patients with advanced cirrhosis.

    Directory of Open Access Journals (Sweden)

    Eiji Kakazu

    Full Text Available BACKGROUND AND AIMS: The innate immune cells can not normally respond to the pathogen in patients with decompensated cirrhosis. Previous studies reported that antigen-presenting cells take up L-Cystine (L-Cys and secrete substantial amounts of L-Glutamate (L-Glu via the transport system Xc- (4F2hc+xCT, and that this exchange influences the immune responses. The aim of this study is to investigate the influence of the plasma L-Cys/L-Glu imbalance observed in patients with advanced cirrhosis on the function of circulating monocytes. METHODS: We used a serum-free culture medium consistent with the average concentrations of plasma amino acids from patients with advanced cirrhosis (ACM, and examined the function of CD14+ monocytes or THP-1 under ACM that contained 0-300 nmol/mL L-Cys with LPS. In patients with advanced cirrhosis, we actually determined the TNF-alpha and xCT mRNA of monocytes, and evaluated the correlation between the plasma L-Cys/L-Glu ratio and TNF-alpha. RESULTS: The addition of L-Cys significantly increased the production of TNF alpha from monocytes under ACM. Monocytes with LPS and THP-1 expressed xCT and a high level of extracellular L-Cys enhanced L-Cys/L-Glu antiport, and the intracellular GSH/GSSG ratio was decreased. The L-Cys transport was inhibited by excess L-Glu. In patients with advanced cirrhosis (n = 19, the TNF-alpha and xCT mRNA of monocytes were increased according to the Child-Pugh grade. The TNF-alpha mRNA of monocytes was significantly higher in the high L-Cys/L-Glu ratio group than in the low ratio group, and the plasma TNF-alpha was significantly correlated with the L-Cys/L-Glu ratio. CONCLUSIONS: A plasma L-Cys/L-Glu imbalance, which appears in patients with advanced cirrhosis, increased the TNF-alpha from circulating monocytes via increasing the intracellular oxidative stress. These results may reflect the immune abnormality that appears in patients with decompensated cirrhosis.

  6. Interleukin-1β,Tumor Necrosis Factor-α and Lipopolysaccharide Induce Expression of Monocyte Chemoattractant Protein-1 in Calf Aortic Smooth Muscle Cells

    Institute of Scientific and Technical Information of China (English)

    MENG Feng; DENG Zhongduan; NI Juan

    2000-01-01

    To investigate whether interleukin-1β(IL-1β), tumor necrosis factor-α (TNF-α) and lipopolysaccharide (LPS) induce expression of monocyte chemoattractant protein-1 (MCP-1)mRNA and protein in calf aortic smooth muscle cells(SMCs), calf aortic SMCs were cultured by a substrate-attached explant method. The cultured SMCs were used between the third to the fifth passage. After the cells became confluent, the SMCs were exposed to 2 ng/ml IL- 1β, 20 ng/mlTNF-lα and 100 ng/ml LPS respectively, and the total RNA of SMCs which were incubated for 4h at 37℃ were extracted from the cells by using guanidinium isothiocyanate method. The expression of MCP-1 mRNA in SMCs was detected by using dot blotting analysis using a probe of γ-32p-end-labelled 35-mer oligonucleotide. After a 24-h incubation, the media conditioned by the cultured SMCs were collected. The MCP-1 protein content in the conditioned media was determined by using sandwich ELISA. The results were as follows: Dot blotting analysis showed that the cultured SMCs could express MCP-1 mRNA. After a 4-h exposure to IL-Iβ, TNF-α and LPS, the MCP-1 mRNA expression in SMCs was increased (3.6-fold, 2.3-fold and 1.6-fold, respectively).ELISA showed that the levels of MCP-1 protein in the conditioned media were also increased (2.9-fold, 1.7-fold and 1.1-fold, respectively ). The results suggest that calf aortic SMCs could express MCP-1 mRNA and protein. IL-1β and TNF-α can induce strong expression of MCP- 1mRNA and protein, and the former is more effective than the latter.

  7. Monocyte chemoattractant protein-1 gene polymorphism and its serum level have an impact on anthropometric and biochemical risk factors of metabolic syndrome in Indian population.

    Science.gov (United States)

    Madeshiya, A K; Singh, S; Dwivedi, S; Saini, K S; Singh, R; Tiwari, S; Konwar, R; Ghatak, A

    2015-04-01

    Monocyte chemoattractant protein-1 (MCP-1), encoded by gene CCL-2 (Chemokine C-C motif 2), is the ligand of chemokine receptor CCR-2. Concurrent clinical alteration in several metabolic aspects, including central obesity, dysglycemia, dyslipidemia and hypertension, is clinically characterized as metabolic syndrome (MetS). Role of MCP-1 in each of these aspects has been established in vitro and in animal studies as well. We here report genetic association of -2518 A>G MCP-1 (rs 1024611) gene polymorphism and level of MCP-1 with MetS in North Indian subjects. We analysed (n=386, controls and n=384, MetS subjects) for MCP-1 gene polymorphism using PCR-RFLP, its serum level using ELISA, anthropometric (body mass index, waist and hip circumferences, waist-hip ratio and blood pressure) and biochemical (serum lipids, plasma glucose and insulin levels) variables in a genetic association study. The body mass index, waist circumference, hip circumference, waist-hip ratio, blood pressure, serum lipids, insulin and fasting plasma glucose level were significantly high in MetS subjects. Regression analysis showed significant correlation of body mass index, waist and hip circumference, systolic/diastolic blood pressure, fasting glucose, total cholesterol, high-density lipoprotein, low-density lipoprotein fasting insulin and HOMA-IR with MetS. MCP-1 allele and genotype were significantly associated with MetS. Serum MCP-1 level was high in overall cases. In conclusions, the MCP-1 2518A>G (rs 1024611) polymorphism has significant impact on risk of MetS, and MCP-1 level correlates with anthropometric and biochemical risk factors of MetS.

  8. Defect of netrophil chemotactic function is one of the etiology of aggressive periodontitis.

    Directory of Open Access Journals (Sweden)

    Yanti Rusyanti

    2016-06-01

    Full Text Available Characteristic of progressive destructive periodontal tissue in Aggressive Periodontitis is a features of disruption of the host-homeostasis as the results of imbalance between host response and specific bacterial pathogenic which presents at gingival sulcus. The objective of this study was to evaluate netrophil function of  Aggressive periodontitis molecularly by means of gen polimorphism of Formyl Peptide Receptor (FPR1 at the surface of netrophil cell, the level of IL-8 and netrophil chemotactic. The results of  the study  can be used as an early detection, prevention or to arrest tissue destruction and to restore a health-associated homeostasis in order to get better prognosis of Aggressive Periodontitis. The study was conducted during 20 months in Periodontic Clinic Dental Hospital, Faculty of Dentistry, Padjadjaran University, Genetica Moleculer Medical Laboratory of Research Institution Padjadjaran University Bandung. Research design used case control methode and sample selection is done in concecutive sampling of 32 aggressive periodontitis patients and 29 non aggressive periodontitis patients who were included in the inclusion criteria. Research materials were venous blood and gingival crevicular fluid. PCR-Sequensing methode was used to asses of gene FPR1 Polimorphism. ELISA methode was used to measure IL-8 level in gingival crevicular fluid, and Human CD66abce Microbead Kit by MACS Separation methode was used to asses netrophil chemotactic. Chi-square test, Fisher’s exact, unpaired t tests were employed to analyse the differences of  characteristic, allele frequencies and genotypic, bivariate analysis to analyse of risk factors and biserial point correlation to analyse correlation between risk factors. The results showed the existence of c576T>C>G gene FPR1 polymorphism 5.040 time-fold (p=0.006; OR=5.040 while the down regulation of IL-8( ≤0.064 pg/µl is 34.5 times-fold of having aggressive periodontitis (OR=34, and c576T

  9. Survival of malnourished head and neck cancer patients can be predicted by human leukocyte antigen-DR expression and interleukin-6/tumor necrosis factor-alpha response of the monocyte.

    Science.gov (United States)

    van Bokhorst-de van der Schuer; von Blomberg-van der Flier, B M; Kuik, D J; Scholten, P E; Siroen, M P; Snow, G B; Quak, J J; van Leeuwen, P A

    2000-01-01

    Patients with advanced stages of head and neck cancer are often characterized by malnutrition and by an impaired immune system. Because some of the suppressed immune parameters were shown to be of prognostic importance in trauma and sepsis, we investigated whether these would also correlate with survival in head and neck cancer. Severely malnourished head and neck cancer patients undergoing ablative and reconstructive surgery were followed prospectively and their perioperative immune parameters were related to long-term survival. Forty-nine patients with a preoperative weight loss of more than 10% were followed up for a period of at least 16 months after surgery. Analyses of variance revealed that preoperative human leukocyte antigen-DR (HLA-DR) expression on monocytes and endotoxin-induced production of tumor necrosis factor-alpha (TNF-alpha) and interleukin-6 (IL-6) were different between patients who survived and patients who died. Proportional hazards identified a weight loss of more than 12%, the presence of coexistent disease, and an HLA-DR expression on monocytes below the cutoff points (mean fluorescence index < 15, peak channel index < 9) to be of significant influence on survival. In addition to known prognostic parameters such as tumor stage, coexistent disease, and weight loss, the immune parameters HLA-DR expression on monocytes and endotoxin-induced cytokine production may carry prognostic value in cancer patients. Immunomodulating therapies leading to improvement of these parameters might in the future lead to increased options for treatment.

  10. Monocyte functions in diabetes mellitus

    DEFF Research Database (Denmark)

    Geisler, C; Almdal, T; Bennedsen, J

    1982-01-01

    The aim of this study was to investigate the functions of monocytes obtained from 14 patients with diabetes mellitus (DM) compared with those of monocytes from healthy individuals. It was found that the total number of circulating monocytes in the 14 diabetic patients was lower than that from...... for the elucidation of concomitant infections in diabetic patients are discussed....

  11. Host hindrance to HIV-1 replication in monocytes and macrophages

    Directory of Open Access Journals (Sweden)

    Pancino Gianfranco

    2010-04-01

    Full Text Available Abstract Monocytes and macrophages are targets of HIV-1 infection and play critical roles in multiple aspects of viral pathogenesis. HIV-1 can replicate in blood monocytes, although only a minor proportion of circulating monocytes harbor viral DNA. Resident macrophages in tissues can be infected and function as viral reservoirs. However, their susceptibility to infection, and their capacity to actively replicate the virus, varies greatly depending on the tissue localization and cytokine environment. The susceptibility of monocytes to HIV-1 infection in vitro depends on their differentiation status. Monocytes are refractory to infection and become permissive upon differentiation into macrophages. In addition, the capacity of monocyte-derived macrophages to sustain viral replication varies between individuals. Host determinants regulate HIV-1 replication in monocytes and macrophages, limiting several steps of the viral life-cycle, from viral entry to virus release. Some host factors responsible for HIV-1 restriction are shared with T lymphocytes, but several anti-viral mechanisms are specific to either monocytes or macrophages. Whilst a number of these mechanisms have been identified in monocytes or in monocyte-derived macrophages in vitro, some of them have also been implicated in the regulation of HIV-1 infection in vivo, in particular in the brain and the lung where macrophages are the main cell type infected by HIV-1. This review focuses on cellular factors that have been reported to interfere with HIV-1 infection in monocytes and macrophages, and examines the evidences supporting their role in vivo, highlighting unique aspects of HIV-1 restriction in these two cell types.

  12. Stability and dynamics of anisotropically-tumbling chemotactic swimmers

    CERN Document Server

    Lushi, Enkeleida

    2016-01-01

    Micro-swimmers such as bacteria E. coli are known to perform random walks known as run-and-tumbles to move up chemo-attractant gradients and as a result aggregate. It is also known that such micro-swimmers can self-organize into macroscopic patterns due to interactions with neighboring cells through the fluidic environment they live in. While the pattern formation resulting from chemotactic and hydrodynamic interactions separately and together have been previously investigated, the effect of the tumbling anisotropy in micro-swimmers has been unexplored. Here we show through linear analysis and full nonlinear simulations that the slight anisotropy in the individual swimmer tumbles can alter the collective pattern formation in non-trivial ways. We show that the tumbling anisotropy diminishes the magnitude of the chemotactic aggregates but may result in more such aggregation peaks.

  13. Analysis of bacterial chemotactic response using dynamic laser speckle

    Science.gov (United States)

    Murialdo, Silvia E.; Sendra, Gonzalo H.; Passoni, Lucía I.; Arizaga, Ricardo; Gonzalez, J. Froilán; Rabal, Héctor; Trivi, Marcelo

    2009-11-01

    Chemotaxis has a meaningful role in several fields, such as microbial physiology, medicine and biotechnology. We present a new application of dynamic laser speckle (or biospeckle) to detect different degrees of bacterial motility during chemotactic response experiments. Encouraging results showed different bacterial dynamic responses due to differences in the hardness of the support in the swarming plates. We compare this method to a conventional technique that uses white light. Both methods showed to be analogous and, in some cases, complementary. The results suggest that biospeckle processed images can be used as an alternative method to evaluate bacterial chemotactic response and can supply additional information about the bacterial motility in different areas of the swarm plate assay that might be useful for biological analysis.

  14. The role of hypoxia inducible factor-1α in the increased MMP-2 and MMP-9 production by human monocytes exposed to nickel nanoparticles

    Science.gov (United States)

    WAN, RONG; MO, YIQUN; CHIEN, SUFAN; LI, YIHUA; LI, YIXIN; TOLLERUD, DAVID J.; ZHANG, QUNWEI

    2016-01-01

    Nickel is an important economic commodity, but it can cause skin sensitization and may cause lung diseases such as lung fibrosis, pneumonitis, bronchial asthma and lung cancer. With development of nanotechnology, nano-sized nickel (Nano-Ni) and nano-sized titanium dioxide (Nano-TiO2) particles have been developed and produced for many years with new formulations and surface properties to meet novel demands. Our previous studies have shown that Nano-Ni instilled into rat lungs caused a greater inflammatory response as compared with standard-sized nickel (5 μm) at equivalent mass concentrations. Nano-Ni caused a persistent high level of inflammation in lungs even at low doses. Recently, several studies have shown that nanoparticles can translocate from the lungs to the circulatory system. To evaluate the potential systemic effects of metal nanoparticles, we compared the effects of Nano-Ni and Nano-TiO2 on matrix metalloproteinases 2 and 9 (MMP-2 and MMP-9) gene expression and activity. Our results showed that exposure of human monocyte U937 to Nano-Ni caused dose- and time- dependent increase in MMP-2 and MMP-9 mRNA expression and pro-MMP-2 and pro-MMP-9 activity, but Nano-TiO2 did not. Nano-Ni also caused dose- and time- related increase in tissue inhibitor of metalloproteinases 1 (TIMP-1), but Nano-TiO2 did not. To determine the potential mechanisms involved, we measured the expression of hypoxia inducible factor 1α (HIF-1α) in U937 cells exposed to Nano-Ni and Nano-TiO2. Our results showed that exposure to Nano-Ni caused HIF-1α accumulation in the nucleus. Furthermore, pre-treatment of U937 cells with heat shock protein 90 (Hsp90) inhibitor, 17-(Allylamino)-17-demethoxygeldanamycin (17-AAG), prior to exposure to Nano-Ni significantly abolished Nano-Ni-induced MMP-2 and MMP-9 mRNA upregulation and increased pro-MMP-2 and pro-MMP-9 activity. Our results suggest that HIF-1α accumulation may be involved in the increased MMP-2 and MMP-9 production in U937 cells

  15. Spasmogenic activity of chemotactic N-formylated oligopeptides: identity of structure--function relationships for chemotactic and spasmogenic activities.

    OpenAIRE

    Marasco, W. A.; Fantone, J. C.; Ward, P. A.

    1982-01-01

    The chemotactic N-formylated oligopeptides are potent spasmogenic agents for guinea pig ileum. Structure-activity studies with various N-formylated peptides suggest the presence of a specific receptor that resembles in specificity the formyl peptide receptor on leukocytes. A competitive antagonist of the formyl peptide receptor on leukocytes also inhibits formyl peptide-induced ileum contraction, whereas the antihistamine diphenhydramine is without effect. The contractile response caused by t...

  16. Sulforaphane reduces vascular inflammation in mice and prevents TNF-α-induced monocyte adhesion to primary endothelial cells through interfering with the NF-κB pathway.

    Science.gov (United States)

    Nallasamy, Palanisamy; Si, Hongwei; Babu, Pon Velayutham Anandh; Pan, Dengke; Fu, Yu; Brooke, Elizabeth A S; Shah, Halley; Zhen, Wei; Zhu, Hong; Liu, Dongmin; Li, Yunbo; Jia, Zhenquan

    2014-08-01

    Sulforaphane, a naturally occurring isothiocyanate present in cruciferous vegetables, has received wide attention for its potential to improve vascular function in vitro. However, its effect in vivo and the molecular mechanism of sulforaphane at physiological concentrations remain unclear. Here, we report that a sulforaphane concentration as low as 0.5 μM significantly inhibited tumor necrosis factor-α (TNF-α)-induced adhesion of monocytes to human umbilical vein endothelial cells, a key event in the pathogenesis of atherosclerosis both in static and under flow conditions. Such physiological concentrations of sulforaphane also significantly suppressed TNF-α-induced production of monocyte chemotactic protein-1 and adhesion molecules including soluble vascular adhesion molecule-1 and soluble E-selectin, key mediators in the regulation of enhanced endothelial cell-monocyte interaction. Furthermore, sulforaphane inhibited TNF-α-induced nuclear factor (NF)-κB transcriptional activity, Inhibitor of NF-κB alpha (IκBα) degradation and subsequent NF-κB p65 nuclear translocation in endothelial cells, suggesting that sulforaphane can inhibit inflammation by suppressing NF-κB signaling. In an animal study, sulforaphane (300 ppm) in a mouse diet significantly abolished TNF-α-increased ex vivo monocyte adhesion and circulating adhesion molecules and chemokines in C57BL/6 mice. Histology showed that sulforaphane treatment significantly prevented the eruption of endothelial lining in the intima layer of the aorta and preserved elastin fibers' delicate organization, as shown by Verhoeff-van Gieson staining. Immunohistochemistry studies showed that sulforaphane treatment also reduced vascular adhesion molecule-1 and monocyte-derived F4/80-positive macrophages in the aorta of TNF-α-treated mice. In conclusion, sulforaphane at physiological concentrations protects against TNF-α-induced vascular endothelial inflammation, in both in vitro and in vivo models. This anti

  17. Spatial regulation of the cAMP-dependent protein kinase during chemotactic cell migration.

    Science.gov (United States)

    Howe, Alan K; Baldor, Linda C; Hogan, Brian P

    2005-10-04

    Historically, the cAMP-dependent protein kinase (PKA) has a paradoxical role in cell motility, having been shown to both facilitate and inhibit actin cytoskeletal dynamics and cell migration. In an effort to understand this dichotomy, we show here that PKA is regulated in subcellular space during cell migration. Immunofluorescence microscopy and biochemical enrichment of pseudopodia showed that type II regulatory subunits of PKA and PKA activity are enriched in protrusive cellular structures formed during chemotaxis. This enrichment correlates with increased phosphorylation of key cytoskeletal substrates for PKA, including the vasodilator-stimulated phosphoprotein (VASP) and the protein tyrosine phosphatase containing a PEST motif. Importantly, inhibition of PKA activity or its ability to interact with A kinase anchoring proteins inhibited the activity of the Rac GTPase within pseudopodia. This effect correlated with both decreased guanine nucleotide exchange factor activity and increased GTPase activating protein activity. Finally, inhibition of PKA anchoring, like inhibition of total PKA activity, inhibited pseudopod formation and chemotactic cell migration. These data demonstrate that spatial regulation of PKA via anchoring is an important facet of normal chemotactic cell movement.

  18. A matrix of cholesterol crystals, but not cholesterol alone, primes human monocytes/macrophages for excessive endotoxin-induced production of tumor necrosis factor-alpha. Role in atherosclerotic inflammation?

    DEFF Research Database (Denmark)

    Bendtzen, Klaus; Christensen, Ole; Nielsen, Claus Henrik

    2014-01-01

    When exposed to small amounts of bacterial endotoxin, matrices of cholesterol crystals, but not cholesterol itself, primed human monocytes/macrophages to a highly augmented (>10-fold) production of inflammatory tumor necrosis factor-α. Priming also sensitized the cells, as 10- to 100-fold lower...... levels of endotoxin were needed for TNF-α production equivalent to that of unprimed cells. The pro-inflammatory effect was selective as endotoxin-induced production of other pro-inflammatory cytokines was unaffected while production of anti-inflammatory interleukin-10 was diminished. These findings...

  19. Monocyte chemoattractant protein-1, trans-forming growth factor-β1, nerve growth factor, resistin and hyaluronic acid as serum markers:comparison between recurrent acute and chronic pancreatitis

    Institute of Scientific and Technical Information of China (English)

    M Ganesh Kamath; C Ganesh Pai; Asha Kamath; Annamma Kurien

    2016-01-01

    BACKGROUND: Diagnostic parameters that can predict the presence of chronic pancreatitis (CP) in patients with recur-rent pain due to pancreatitis would help to direct appropri-ate therapy. This study aimed to compare the serum levels of monocyte chemoattractant protein-1 (MCP-1), transforming growth factor-β1 (TGF-β1), nerve growth factor (NGF), resis-tin and hyaluronic acid (HA) in patients with recurrent acute pancreatitis (RAP) and CP to assess their ability to differenti-ate the two conditions. METHODS: Levels of serum markers assessed by enzyme-linked immunosorbent assay (ELISA) were prospectively com-pared in consecutive patients with RAP, CP and in controls, and stepwise discriminant analysis was performed to identify the markers differentiating RAP from CP. RESULTS: One hundred and thirteen consecutive patients (RAP=32, CP=81) and 78 healthy controls were prospectively enrolled. The mean (SD) age of the patients was 32.0 (14.0) years; 89 (78.8%) were male. All markers were signiifcantly higher in CP patients than in the controls (P CONCLUSION: Serum resistin is a promising marker to dif-ferentiate between RAP and CP and needs validation in future studies, especially in those with early CP.

  20. HIV-1 Tat Protein Activates both the MyD88 and TRIF Pathways To Induce Tumor Necrosis Factor Alpha and Interleukin-10 in Human Monocytes.

    Science.gov (United States)

    Planès, Rémi; Ben Haij, Nawal; Leghmari, Kaoutar; Serrero, Manutea; BenMohamed, Lbachir; Bahraoui, Elmostafa

    2016-07-01

    In this study, we show that the HIV-1 Tat protein interacts with rapid kinetics to engage the Toll-like receptor 4 (TLR4) pathway, leading to the production of proinflammatory and anti-inflammatory cytokines. The pretreatment of human monocytes with Tat protein for 10 to 30 min suffices to irreversibly engage the activation of the TLR4 pathway, leading to the production of tumor necrosis factor alpha (TNF-α) and interleukin-10 (IL-10), two cytokines strongly implicated in the chronic activation and dysregulation of the immune system during HIV-1 infection. Therefore, this study analyzed whether the HIV-1 Tat protein is able to activate these two pathways separately or simultaneously. Using three complementary approaches, including mice deficient in the MyD88, TIRAP/MAL, or TRIF adaptor, biochemical analysis, and the use of specific small interfering RNAs (siRNAs), we demonstrated (i) that Tat was able to activate both the MyD88 and TRIF pathways, (ii) the capacity of Tat to induce TIRAP/MAL degradation, (iii) the crucial role of the MyD88 pathway in the production of Tat-induced TNF-α and IL-10, (iv) a reduction but not abrogation of IL-10 and TNF-α by Tat-stimulated macrophages from mice deficient in TIRAP/MAL, and (v) the crucial role of the TRIF pathway in Tat-induced IL-10 production. Further, we showed that downstream of the MyD88 and TRIF pathways, the Tat protein activated the protein kinase C (PKC) βII isoform, the mitogen-activated protein (MAP) kinases p38 and extracellular signal-regulated kinase 1/2 (ERK1/2), and NF-κB in a TLR4-dependent manner. Collectively, our data show that by recruiting the TLR4 pathway with rapid kinetics, the HIV-1 Tat protein leads to the engagement of both the MyD88 and TRIF pathways and to the activation of PKC, MAP kinase, and NF-κB signaling to induce the production of TNF-α and IL-10. In this study, we demonstrate that by recruiting the TLR4 pathway with rapid kinetics, the HIV-1 Tat protein leads to the engagement

  1. Dyslipidemic Diet-Induced Monocyte “Priming” and Dysfunction in Non-Human Primates Is Triggered by Elevated Plasma Cholesterol and Accompanied by Altered Histone Acetylation

    Directory of Open Access Journals (Sweden)

    John D. Short

    2017-08-01

    Full Text Available Monocytes and the recruitment of monocyte-derived macrophages into sites of inflammation play a key role in atherogenesis and other chronic inflammatory diseases linked to cardiometabolic syndrome and obesity. Previous studies from our group have shown that metabolic stress promotes monocyte priming, i.e., enhanced adhesion and accelerated chemotaxis of monocytes in response to chemokines, both in vitro and in dyslipidemic LDLR−/− mice. We also showed that metabolic stress-induced monocyte dysfunction is, at least to a large extent caused by the S-glutathionylation, inactivation, and subsequent degradation of mitogen-activated protein kinase phosphatase 1. Here, we analyzed the effects of a Western-style, dyslipidemic diet (DD, which was composed of high levels of saturated fat, cholesterol, and simple sugars, on monocyte (dysfunction in non-human primates (NHPs. We found that similar to mice, a DD enhances monocyte chemotaxis in NHP within 4 weeks, occurring concordantly with the onset of hypercholesterolemia but prior to changes in triglycerides, blood glucose, monocytosis, or changes in monocyte subset composition. In addition, we identified transitory decreases in the acetylation of histone H3 at the lysine residues 18 and 23 in metabolically primed monocytes, and we found that monocyte priming was correlated with the acetylation of histone H3 at lysine 27 after an 8-week DD regimen. Our data show that metabolic stress promotes monocyte priming and hyper-chemotactic responses in NHP. The histone modifications accompanying monocyte priming in primates suggest a reprogramming of the epigenetic landscape, which may lead to dysregulated responses and functionalities in macrophages derived from primed monocytes that are recruited to sites of inflammation.

  2. Predicted auxiliary navigation mechanism of peritrichously flagellated chemotactic bacteria.

    Directory of Open Access Journals (Sweden)

    Nikita Vladimirov

    2010-03-01

    Full Text Available Chemotactic movement of Escherichia coli is one of the most thoroughly studied paradigms of simple behavior. Due to significant competitive advantage conferred by chemotaxis and to high evolution rates in bacteria, the chemotaxis system is expected to be strongly optimized. Bacteria follow gradients by performing temporal comparisons of chemoeffector concentrations along their runs, a strategy which is most efficient given their size and swimming speed. Concentration differences are detected by a sensory system and transmitted to modulate rotation of flagellar motors, decreasing the probability of a tumble and reorientation if the perceived concentration change during a run is positive. Such regulation of tumble probability is of itself sufficient to explain chemotactic drift of a population up the gradient, and is commonly assumed to be the only navigation mechanism of chemotactic E. coli. Here we use computer simulations to predict existence of an additional mechanism of gradient navigation in E. coli. Based on the experimentally observed dependence of cell tumbling angle on the number of switching motors, we suggest that not only the tumbling probability but also the degree of reorientation during a tumble depend on the swimming direction along the gradient. Although the difference in mean tumbling angles up and down the gradient predicted by our model is small, it results in a dramatic enhancement of the cellular drift velocity along the gradient. We thus demonstrate a new level of optimization in E. coli chemotaxis, which arises from the switching of several flagellar motors and a resulting fine tuning of tumbling angle. Similar strategy is likely to be used by other peritrichously flagellated bacteria, and indicates yet another level of evolutionary development of bacterial chemotaxis.

  3. Jeans type instability for a chemotactic model of cellular aggregation

    CERN Document Server

    Chavanis, Pierre-Henri

    2008-01-01

    We consider an inertial model of chemotactic aggregation generalizing the Keller-Segel model and we study the linear dynamical stability of an infinite and homogeneous distribution of cells (bacteria, amoebae, endothelial cells,...) when inertial effects are accounted for. These inertial terms model cells directional persistance. We determine the condition of instability and the growth rate of the perturbation as a function of the cell density and the wavelength of the perturbation. We discuss the differences between overdamped (Keller-Segel) and inertial models. Finally, we show the analogy between the instability criterion for biological populations and the Jeans instability criterion in astrophysics.

  4. Bifurcation in the chemotactic behavior of Physarum plasmodium

    Science.gov (United States)

    Shirakawa, Tomohiro; Gunji, Yukio-Pegio; Sato, Hiroshi; Tsubakino, Hiroto

    2017-07-01

    The plasmodium of true slime mold Physarum polycephalum is a unicellular and multinuclear giant amoeba. Since the cellular organism has some computational abilities, it is attracting much attention in the field of information science. However, previous studies have mainly focused on the optimization behavior of the plasmodium for a single-modality stimulus, and there are few studies on how the organism adapts to multi-modal stimuli. We stimulated the plasmodium with mixture of attractant and repellent stimuli, and we observed bifurcation in the chemotactic behavior of the plasmodium.

  5. 生物活性肽-单核细胞迁移抑制因子研究进展%Research progress of bioactive peptide monocyte locomotion inhibitory factor

    Institute of Scientific and Technical Information of China (English)

    程浩; 芮耀诚; 章越凡; 李铁军

    2015-01-01

    Monocyte locomotion inhibitory factor(MLIF)was an anti‐inflammatory pentapeptide produced by Entamoeba histolytica .In vivo and in vitro study showed that MLIF displayed anti‐inflammatory and immune protection effects and MLIF had protective effects on rheumatoid arthritis ,nerve injury ,myocardial ischemia ,cerebral ischemia and Alzheimer′s disease . Studies had shown that MLIF regulated inflammatory response and immune protection through NF‐κB and MAPK signal path‐ways .The sources and biological activities of MLIF were reviewed in this paper .%单核细胞迁移抑制因子(monocyte locomotion inhibitory factor ,MLIF)是阿米巴原虫产生的具有抗炎作用的五肽。体内、外研究发现,M LIF可以发挥抗炎和免疫保护作用,对类风湿关节炎、神经损伤、心肌缺血、脑缺血及痴呆具有良好的保护作用。研究证明MLIF通过NF‐κB和MAPK信号通路调节炎症反应和免疫保护。笔者对MLIF的来源和生物活性做一综述。

  6. Increasing body condition score is positively associated interleukin-6 and monocyte chemoattractant protein-1 in Labrador retrievers.

    Science.gov (United States)

    Frank, Lauren; Mann, Sabine; Levine, Corri B; Cummings, Bethany P; Wakshlag, Joseph J

    2015-10-15

    The accumulation of excess body fat is a growing problem in dogs as well as people. Contrary to prior understanding of adipose tissue, fat is now considered to be an active endocrine organ that promotes a chronic low-grade inflammatory state often characterized by an increase in pro-inflammatory cytokines and chemokines. These have been implicated in several obesity-related disorders such as insulin resistance, cardiovascular disease, and neoplasia. The purpose of this study was to characterize fasting plasma cytokine concentrations in ninety-two healthy client-owned Labrador retriever dogs of various ages and body condition scores. The dogs were grouped according to body condition score (BCS) into three categories, lean, overweight and obese. The following cytokines and chemokines were evaluated; tumor necrosis factor-alpha, interleukin-2, interleukin-6, interleukin-8, and monocyte chemotactic protein-1 (TNF-α, IL-2, IL-6, IL-8, MCP-1). Our results indicated that fasting plasma IL-6 and MCP-1 concentrations are associated with increasing BCS. This data suggest that certain markers of inflammation increase with increasing body condition score, and that dogs, similar to humans, may be fostering a chronic inflammatory state due to obesity.

  7. Collective cell motility promotes chemotactic prowess and resistance to chemorepulsion.

    Science.gov (United States)

    Malet-Engra, Gema; Yu, Weimiao; Oldani, Amanda; Rey-Barroso, Javier; Gov, Nir S; Scita, Giorgio; Dupré, Loïc

    2015-01-19

    Collective cell migration is a widespread biological phenomenon, whereby groups of highly coordinated, adherent cells move in a polarized fashion. This migration mode is a hallmark of tissue morphogenesis during development and repair and of solid tumor dissemination. In addition to circulating as solitary cells, lymphoid malignancies can assemble into tissues as multicellular aggregates. Whether malignant lymphocytes are capable of coordinating their motility in the context of chemokine gradients is, however, unknown. Here, we show that, upon exposure to CCL19 or CXCL12 gradients, malignant B and T lymphocytes assemble into clusters that migrate directionally and display a wider chemotactic sensitivity than individual cells. Physical modeling recapitulates cluster motility statistics and shows that intracluster cell cohesion results in noise reduction and enhanced directionality. Quantitative image analysis reveals that cluster migration runs are periodically interrupted by transitory rotation and random phases that favor leader cell turnover. Additionally, internalization of CCR7 in leader cells is accompanied by protrusion retraction, loss of polarity, and the ensuing replacement by new leader cells. These mechanisms ensure sustained forward migration and resistance to chemorepulsion, a behavior of individual cells exposed to steep CCL19 gradients that depends on CCR7 endocytosis. Thus, coordinated cluster dynamics confer distinct chemotactic properties, highlighting unexpected features of lymphoid cell migration.

  8. Global solution for a chemotactic haptotactic model of cancer invasion

    Science.gov (United States)

    Tao, Youshan; Wang, Mingjun

    2008-10-01

    This paper deals with a mathematical model of cancer invasion of tissue recently proposed by Chaplain and Lolas. The model consists of a reaction-diffusion-taxis partial differential equation (PDE) describing the evolution of tumour cell density, a reaction-diffusion PDE governing the evolution of the proteolytic enzyme concentration and an ordinary differential equation modelling the proteolysis of the extracellular matrix (ECM). In addition to random motion, the tumour cells are directed not only by haptotaxis (cellular locomotion directed in response to a concentration gradient of adhesive molecules along the ECM) but also by chemotaxis (cellular locomotion directed in response to a concentration gradient of the diffusible proteolytic enzyme). In one space dimension, the global existence and uniqueness of a classical solution to this combined chemotactic-haptotactic model is proved for any chemotactic coefficient χ > 0. In two and three space dimensions, the global existence is proved for small χ/μ (where μ is the logistic growth rate of the tumour cells). The fundamental point of proof is to raise the regularity of a solution from L1 to Lp (p > 1). Furthermore, the existence of blow-up solutions to a sub-model in two space dimensions for large χ shows, to some extent, that the condition that χ/μ is small is necessary for the global existence of a solution to the full model.

  9. Monocytes regulate systemic coagulation and inflammation in abdominal sepsis.

    Science.gov (United States)

    Wang, Yongzhi; Braun, Oscar Ö; Zhang, Su; Norström, Eva; Thorlacius, Henrik

    2015-03-01

    Abdominal sepsis is associated with significant changes in systemic inflammation and coagulation. The purpose of the present study was to examine the role of peripheral blood monocytes for systemic coagulation, including thrombin generation and consumption of coagulation factors. Abdominal sepsis was induced by cecal ligation and puncture (CLP) in C57BL/6 mice. Plasma and lung levels of IL-6 and C-X-C motif (CXC) chemokines [chemokine CXC ligand (CXCL)1, CXCL2, and CXCL5], pulmonary activity of myeloperoxidase, thrombin generation, and coagulation factors were determined 6 h after CLP induction. Administration of clodronate liposomes decreased circulating levels of monocytes by 96%. Time to peak thrombin formation was increased and peak and total thrombin generation was decreased in plasma from CLP animals. Monocyte depletion decreased time to peak formation of thrombin and increased peak and total generation of thrombin in septic animals. In addition, monocyte depletion decreased the CLP-induced increase in the levels of thrombin-antithrombin complexes in plasma. Depletion of monocytes increased plasma levels of prothrombin, factor V, factor X, and protein C in septic mice. Moreover, depletion of monocytes decreased CLP-induced levels of IL-6 and CXC chemokines in the plasma and lung by >59% and 20%, respectively. CLP-induced myeloperoxidase activity in the lung was attenuated by 44% in animals depleted of monocytes. Taken together, our findings show, for the first time, that peripheral blood monocytes regulate systemic coagulation. The results of our study improve our understanding of the pathophysiology of sepsis and encourage further attempts to target innate immune cell functions in abdominal sepsis.

  10. Transcriptome analysis of monocyte-HIV interactions

    Directory of Open Access Journals (Sweden)

    Tran Huyen

    2010-06-01

    Full Text Available Abstract Background During HIV infection and/or antiretroviral therapy (ART, monocytes and macrophages exhibit a wide range of dysfunctions which contribute significantly to HIV pathogenesis and therapy-associated complications. Nevertheless, the molecular components which contribute to these dysfunctions remain elusive. We therefore applied a parallel approach of genome-wide microarray analysis and focused gene expression profiling on monocytes from patients in different stages of HIV infection and/or ART to further characterise these dysfunctions. Results Processes involved in apoptosis, cell cycle, lipid metabolism, proteasome function, protein trafficking and transcriptional regulation were identified as areas of monocyte dysfunction during HIV infection. Individual genes potentially contributing to these monocyte dysfunctions included several novel factors. One of these is the adipocytokine NAMPT/visfatin, which we show to be capable of inhibiting HIV at an early step in its life cycle. Roughly half of all genes identified were restored to control levels under ART, while the others represented a persistent dysregulation. Additionally, several candidate biomarkers (in particular CCL1 and CYP2C19 for the development of the abacavir hypersensitivity reaction were suggested. Conclusions Previously described areas of monocyte dysfunction during HIV infection were confirmed, and novel themes were identified. Furthermore, individual genes associated with these dysfunctions and with ART-associated disorders were pinpointed. These genes form a useful basis for further functional studies concerning the contribution of monocytes/macrophages to HIV pathogenesis. One such gene, NAMPT/visfatin, represents a possible novel restriction factor for HIV. Background Both macrophages and T lymphocyte subsets express the CD4 receptor and either the CXCR4 and/or the CCR5 coreceptor which confer susceptibility to infection with the Human Immunodeficiency Virus

  11. Vascular Leakage in Dengue Hemorrhagic Fever Is Associated with Dengue Infected Monocytes, Monocyte Activation/Exhaustion, and Cytokines Production

    Directory of Open Access Journals (Sweden)

    Sirichan Chunhakan

    2015-01-01

    Full Text Available The vascular leakage was shown by the increment of hematocrit (Hct, dengue viral infected monocyte, monocyte status, and cytokines production in patients infected with dengue virus. Dengue viral antigens were demonstrated in monocytes (CD14+ from peripheral blood mononuclear cells. The increased levels of Hct, interleukin- (IL- 10, and tumor necrosis factor-alpha (TNF-α were detected in dengue fever (DF, dengue hemorrhagic fever (DHF and dengue shock syndrome (DSS patients as compared with other febrile illnesses (OFIs. The highest levels of Hct and IL-10 were detected in DSS patients as compared with other groups (P<0.05 especially on one day before and after defervescence. The unstimulated and lipopolysaccharide- (LPS- stimulated monocytes from DSS patients showed the significantly decreased of intracellular IL-1β and TNF-α. In addition, the lowest level of mean fluorescence intensity (MFI of CD11b expression on monocytes surface in DSS patients was also demonstrated. Furthermore, the negative correlations between IL-10 levels and intracellular IL-1β and MFI of CD11b expression in unstimulated and LPS-stimulated monocytes were also detected. Nevertheless, not only were the relationships between the prominent IL-10 and the suppression of intracellular monocyte secretion, namely, IL-1β, TNF-α, demonstrated but also the effect of vascular leakage was observed.

  12. The dysregulation of the monocyte/macrophage effector function induced by isopropanol is mediated by the defective activation of distinct members of the AP-1 family of transcription factors.

    Science.gov (United States)

    Carignan, Damien; Désy, Olivier; de Campos-Lima, Pedro O

    2012-01-01

    Isopropanol is the second most common cause of short-chain alcohol acute intoxication. Nonethanolic short-chain alcohols mediate their immunomodulatory effect by interfering with nuclear factor of activated T cells (NFAT) activation with or without additional activator protein-1 (AP-1) involvement. In the present study, we examined the immunomodulation induced by isopropanol in conditions that are not reliant on NFAT: the inflammatory cytokine response of lipopolysaccharide (LPS)-stimulated monocytes. Our hypothesis was that isopropanol acute exposure would have an attenuated effect or no consequence in this setting. To our surprise, the impairment of AP-1 activation was sufficient to mediate a severe and dose-dependent phenotype in human monocytes in vitro at alcohol concentrations as low as 0.16% (or 26 mM). There were three outcomes: interleukin (IL)-1β/IL-8 were unaltered; IL-6 was upregulated; and tumor necrosis factor alpha (TNF-α)/CCL2 were downregulated. The effector function of human monocyte-derived macrophages was also compromised. Our results showed that Toll-like receptor 4 early signaling was preserved, as isopropanol did not change the kinase activity of the IL-1 receptor-associated kinase 1 in LPS-stimulated cells. The nuclear factor-κB signaling cascade and the p38/c-Jun N-terminal kinase modules of the mitogen-activated protein kinase pathway were alcohol insensitive. Conversely, the activation of extracellular signal-regulated protein kinase and, ultimately, of c-Fos and JunB were impaired. The alcohol-induced cytokine dysregulation was confirmed in a mouse model of isopropanol intoxication in which the production of TNF-α in response to LPS challenge was virtually abolished. The magnitude of this alcohol effect was sufficiently high to rescue animals from LPS-induced toxic shock. Our data contribute to the dismal body of information on the immunotoxicology of isopropanol, one of the most ubiquitous chemicals to which the general population

  13. Phenomenological understanding of aggregation and dispersion of chemotactic cells

    CERN Document Server

    Iwasa, Masatomo

    2011-01-01

    We present a simple model that describes the motion of a single chemotactic cell exposed to a traveling wave of the chemoattractant. The model incorporates two types of responses to stimulation by the chemoattractant, i.e., change in polarity and change in motility of the cell. The periodic change in motility is assumed to be induced by the periodic stimulation by the chemoattractant on the basis of previous observations. Consequently, net migration of the cell occurs in a particular direction with respect to wave propagation, which explains the migration of Dictyostelium cells in aggregation processes. The difference between two time delays from the stimulation to the two responses and the wave frequency determined by the frequency of the secretion of the chemoattractant are important parameters that determine the direction of migration and the effective interaction between cells in a population. This result explains the dispersed state of a population of vegetative cells and cells in preaggregation without ...

  14. Controlling neural activity in Caenorhabditis elegans to evoke chemotactic behavior

    Science.gov (United States)

    Kocabas, Askin; Shen, Ching-Han; Guo, Zengcai V.; Ramanathan, Sharad

    2013-03-01

    Animals locate and track chemoattractive gradients in the environment to find food. With its simple nervous system, Caenorhabditis elegans is a good model system in which to understand how the dynamics of neural activity control this search behavior. To understand how the activity in its interneurons coordinate different motor programs to lead the animal to food, here we used optogenetics and new optical tools to manipulate neural activity directly in freely moving animals to evoke chemotactic behavior. By deducing the classes of activity patterns triggered during chemotaxis and exciting individual neurons with these patterns, we identified interneurons that control the essential locomotory programs for this behavior. Notably, we discovered that controlling the dynamics of activity in just one interneuron pair was sufficient to force the animal to locate, turn towards and track virtual light gradients.

  15. Monocyte and Macrophage Plasticity in Tissue Repair and Regeneration

    Science.gov (United States)

    Das, Amitava; Sinha, Mithun; Datta, Soma; Abas, Motaz; Chaffee, Scott; Sen, Chandan K.; Roy, Sashwati

    2016-01-01

    Heterogeneity and high versatility are the characteristic features of the cells of monocyte-macrophage lineage. The mononuclear phagocyte system, derived from the bone marrow progenitor cells, is primarily composed of monocytes, macrophages, and dendritic cells. In regenerative tissues, a central role of monocyte-derived macrophages and paracrine factors secreted by these cells is indisputable. Macrophages are highly plastic cells. On the basis of environmental cues and molecular mediators, these cells differentiate to proinflammatory type I macrophage (M1) or anti-inflammatory or proreparative type II macrophage (M2) phenotypes and transdifferentiate into other cell types. Given a central role in tissue repair and regeneration, the review focuses on the heterogeneity of monocytes and macrophages with current known mechanisms of differentiation and plasticity, including microenvironmental cues and molecular mediators, such as noncoding RNAs. PMID:26118749

  16. Derivation of multipotent progenitors from human circulating CD14+ monocytes.

    Science.gov (United States)

    Seta, Noriyuki; Kuwana, Masataka

    2010-07-01

    Circulating CD14(+) monocytes are originated from hematopoietic stem cells in the bone marrow and believed to be committed precursors for phagocytes, such as macrophages. Recently, we have reported a primitive cell population termed monocyte-derived multipotential cells (MOMCs), which has a fibroblast-like morphology in culture and a unique phenotype positive for CD14, CD45, CD34, and type I collagen. MOMCs are derived from circulating CD14(+) monocytes, but circulating precursors for MOMCs still remain undetermined. Comparative analysis of gene expression profiles of MOMCs and other monocyte-derived cells has revealed that embryonic stem cell markers, Nanog and Oct-4, are specifically expressed by MOMCs. In vitro generation of MOMCs requires binding to fibronectin and exposure to soluble factors derived from activated platelets. MOMCs contain progenitors with capacity to differentiate into a variety of nonphagocytes, including bone, cartilage, fat, skeletal and cardiac muscle, neuron, and endothelium, indicating that circulating monocytes are more multipotent than previously thought. In addition, MOMCs are capable of promoting ex vivo expansion of human hematopoietic progenitor cells through direct cell-to-cell contact and secretion of a variety of hematopoietic growth factors. These findings obtained from the research on MOMCs indicate that CD14(+) monocytes in circulation are involved in a variety of physiologic functions other than innate and acquired immune responses, such as repair and regeneration of the damaged tissue.

  17. Targeting monocyte chemotactic protein-1 synthesis with bindarit induces tumor regression in prostate and breast cancer animal models.

    Science.gov (United States)

    Zollo, Massimo; Di Dato, Valeria; Spano, Daniela; De Martino, Daniela; Liguori, Lucia; Marino, Natascia; Vastolo, Viviana; Navas, Luigi; Garrone, Beatrice; Mangano, Giorgina; Biondi, Giuseppe; Guglielmotti, Angelo

    2012-08-01

    Prostate and breast cancer are major causes of death worldwide, mainly due to patient relapse upon disease recurrence through formation of metastases. Chemokines are small proteins with crucial roles in the immune system, and their regulation is finely tuned in early inflammatory responses. They are key molecules during inflammatory processes, and many studies are focusing on their regulatory functions in tumor growth and angiogenesis during metastatic cell seeding and spreading. Bindarit is an anti-inflammatory indazolic derivative that can inhibit the synthesis of MCP-1/CCL2, with a potential inhibitory function in tumor progression and metastasis formation. We show here that in vitro, bindarit can modulate cancer-cell proliferation and migration, mainly through negative regulation of TGF-β and AKT signaling, and it can impair the NF-κB signaling pathway through enhancing the expression of the NF-κB inhibitor IkB-α. In vivo administration of bindarit results in impaired metastatic disease in prostate cancer xenograft mice (PC-3M-Luc2 cells injected intra-cardially) and impairment of local tumorigenesis in syngeneic Balb/c mice injected under the mammary gland with murine breast cancer cells (4T1-Luc cells). In addition, bindarit treatment significantly decreases the infiltration of tumor-associated macrophages and myeloid-derived suppressor cells in 4T1-Luc primary tumors. Overall, our data indicate that bindarit is a good candidate for new therapies against prostate and breast tumorigenesis, with an action through impairment of inflammatory cell responses during formation of the tumor-stroma niche microenvironment.

  18. Infection-induced bystander-apoptosis of monocytes is TNF-alpha-mediated.

    Directory of Open Access Journals (Sweden)

    Stephan Dreschers

    Full Text Available Phagocytosis induced cell death (PICD is crucial for controlling phagocyte effector cells, such as monocytes, at sites of infection, and essentially contributes to termination of inflammation. Here we tested the hypothesis, that during PICD bystander apoptosis of non-phagocyting monocytes occurs, that apoptosis induction is mediated via tumor necrosis factor-alpha (TNF-α and that TNF-α secretion and -signalling is causal. Monocytes were infected with Escherichia coli (E. coli, expressing green fluorescent protein (GFP, or a pH-sensitive Eos-fluorescent protein (EOS-FP. Monocyte phenotype, phagocytic activity, apoptosis, TNF-receptor (TNFR-1, -2-expression and TNF-α production were analyzed. Apoptosis occured in phagocyting and non-phagocyting, bystander monocytes. Bacterial transport to the phagolysosome was no prerequisite for apoptosis induction, and desensitized monocytes from PICD, as confirmed by EOS-FP expressing E. coli. Co-cultivation with non-infected carboxyfluorescein-succinimidyl-ester- (CFSE- labelled monocytes resulted in significant apoptotic cell death of non-infected bystander monocytes. This process required protein de-novo synthesis and still occurred in a diminished way in the absence of cell-cell contact. E. coli induced a robust TNF-α production, leading to TNF-mediated apoptosis in monocytes. Neutralization with an anti-TNF-α antibody reduced monocyte bystander apoptosis significantly. In contrast to TNFR2, the pro-apoptotic TNFR1 was down-regulated on the monocyte surface, internalized 30 min. p.i. and led to apoptosis predominantly in monocytes without phagocyting bacteria by themselves. Our results suggest, that apoptosis of bystander monocytes occurs after infection with E. coli via internalization of TNFR1, and indicate a relevant role for TNF-α. Modifying monocyte apoptosis in sepsis may be a future therapeutic option.

  19. Endotoxin-induced maturation of monocytes in preterm fetal sheep lung.

    Science.gov (United States)

    Kramer, Boris W; Joshi, Shubhada N; Moss, Timothy J M; Newnham, John P; Sindelar, Richard; Jobe, Alan H; Kallapur, Suhas G

    2007-08-01

    The fetal lung normally contains immature monocytes and very few mature macrophages. The chorioamnionitis frequently associated with preterm birth induces monocyte influx into the fetal lung. Previous studies demonstrated that monocytes in the developing lung can mediate lung injury responses that resemble BPD in humans. We hypothesized that chorioamnionitis would induce maturation of immature monocytes in the fetal lung. Groups of three to seven time-mated ewes received saline or 10 mg of endotoxin (Escherichia coli 055:B5) in saline by intra-amniotic injection for intervals from 1 to 14 days before operative delivery at 124 days of gestational age. Monocytic cells from lung tissue were recovered using Percoll gradients. Monocytic cells consistent with macrophages were identified morphologically and by myosin heavy chain class II expression. An increase in macrophages was preceded by induction of granulocyte-macrophage colony-stimulating factor in the lung and subsequent activation of the transcription factor PU.1. The production of IL-6 by monocytes/macrophages in response to endotoxin challenge in vitro increased 7 and 14 days after exposure to intra-amniotic endotoxin. Recombinant TNF-alpha induced IL-6 production by lung monocytic cells exposed to intra-amniotic endotoxin but not in control cells. Monocytic phagocytosis of apoptotic neutrophils also increased 7 and 14 days after exposure to intra-amniotic endotoxin. Intra-amniotic endotoxin induced lung monocytes to develop into functionally mature cells consistent with macrophages. These findings have implications for lung immune responses after exposure to chorioamnionitis.

  20. Spasmogenic activity of chemotactic N-formylated oligopeptides: identity of structure--function relationships for chemotactic and spasmogenic activities.

    Science.gov (United States)

    Marasco, W A; Fantone, J C; Ward, P A

    1982-12-01

    The chemotactic N-formylated oligopeptides are potent spasmogenic agents for guinea pig ileum. Structure-activity studies with various N-formylated peptides suggest the presence of a specific receptor that resembles in specificity the formyl peptide receptor on leukocytes. A competitive antagonist of the formyl peptide receptor on leukocytes also inhibits formyl peptide-induced ileum contraction, whereas the antihistamine diphenhydramine is without effect. The contractile response caused by the synthetic N-formylated peptides differs from those induced by acetylcholine, histamine, and substance P. In particular, a latent period after treatment with the N-formyl peptides is seen before the onset of the response, and a sustained contractile response is not maintained. In addition, tachyphylaxis does occur, but complete recovery of activity is seen after a 20- to 30-min rest period. These observations suggest broad biological roles of prokaryotic signal peptides from bacteria as acute inflammatory mediators.

  1. An in vitro coculture model of transmigrant monocytes and foam cell formation.

    Science.gov (United States)

    Takaku, M; Wada, Y; Jinnouchi, K; Takeya, M; Takahashi, K; Usuda, H; Naito, M; Kurihara, H; Yazaki, Y; Kumazawa, Y; Okimoto, Y; Umetani, M; Noguchi, N; Niki, E; Hamakubo, T; Kodama, T

    1999-10-01

    To analyze in vitro the migration of monocytes to the subendothelial space, their differentiation into macrophages, and the subsequent formation of foam cells in vitro, we have developed a 2-coculture system with rabbit aortic endothelial cells (AECs), aortic smooth muscle cells (SMCs), and a mixture of matrix proteins on polyethylene filters in chemotaxis chambers. AECs were seeded on a mixture of type I and IV collagen with or without various types of serum lipoproteins (method 1) or on matrix proteins secreted by SMCs (method 2). In these coculture systems, rabbit AECs can maintain a well-preserved monolayer for up to 2 weeks. When human CD14-positive monocytes were added to the upper medium of the system, with monocyte chemotactic protein-1 treatment approximately 60% of the monocytes transmigrated within 24 hours and were retained for up to 7 days, whereas without MCP-1 treatment, monocytes transmigrated. On day 1, transmigrant monocytes were negative for immunostaining of type I and II macrophage scavenger receptors but by day 3, became positive for scavenger receptors as well as other macrophage markers. When oxidized low density lipoprotein was added to the matrix layer of the method I coculture, on day 4 transmigrant cells exhibited lipid deposit droplets, and by day 7, they had the appearance of typical foam cells. Some of the transmigrant cells recovered in the lower medium on day 7 also appeared to be foam cells, indicating foam cell motility and escape from the coculture layer through the filter. In summary, this coculture system is a useful in vitro tool to dissect the cellular and molecular events that make up the process of foam cell formation.

  2. Meisoindigo, but not its core chemical structure indirubin, inhibits zebrafish interstitial leukocyte chemotactic migration.

    Science.gov (United States)

    Ye, Baixin; Xiong, Xiaoxing; Deng, Xu; Gu, Lijuan; Wang, Qiongyu; Zeng, Zhi; Gao, Xiang; Gao, Qingping; Wang, Yueying

    2017-12-01

    Inflammatory disease is a big threat to human health. Leukocyte chemotactic migration is required for efficient inflammatory response. Inhibition of leukocyte chemotactic migration to the inflammatory site has been shown to provide therapeutic targets for treating inflammatory diseases. Our study was designed to discover effective and safe compounds that can inhibit leukocyte chemotactic migration, thus providing possible novel therapeutic strategy for treating inflammatory diseases. In this study, we used transgenic zebrafish model (Tg:zlyz-EGFP line) to visualize the process of leukocyte chemotactic migration. Then, we used this model to screen the hit compound and evaluate its biological activity on leukocyte chemotactic migration. Furthermore, western blot analysis was performed to evaluate the effect of the hit compound on the AKT or ERK-mediated pathway, which plays an important role in leukocyte chemotactic migration. In this study, using zebrafish-based chemical screening, we identified that the hit compound meisoindigo (25 μM, 50 μM, 75 μM) can significantly inhibit zebrafish leukocyte chemotactic migration in a dose-dependent manner (p = 0.01, p = 0.0006, p migration (p = 0.43). Furthermore, our results unexpectedly showed that indirubin, the core structure of meisoindigo, had no significant effect on zebrafish leukocyte chemotactic migration (p = 0.6001). Additionally, our results revealed that meisoindigo exerts no effect on the Akt or Erk-mediated signalling pathway. Our results suggest that meisoindigo, but not indirubin, is effective for inhibiting leukocyte chemotactic migration, thus providing a potential therapeutic agent for treating inflammatory diseases.

  3. Matrine Inhibits Infiltration of the Inflammatory Gr1hi Monocyte Subset in Injured Mouse Liver through Inhibition of Monocyte Chemoattractant Protein-1

    Directory of Open Access Journals (Sweden)

    Duo Shi

    2013-01-01

    Full Text Available Matrine (Mat is a major alkaloid extracted from Sophora flavescens Ait, an herb which is used in the traditional Chinese medicine for treatment of inflammation, cancer, and other diseases. The present study examined the impact of Mat on the CCl4-induced hepatic infiltration of Gr1hi monocytes to explore the possible mechanisms underlying its anti-inflammatory and antifibrotic effects. The results indicated that Mat protected mice from acute liver injury induced by single intraperitoneal injection of CCl4 and attenuated liver fibrosis induced by repeated CCl4 injection. Meanwhile, the infiltrations of Gr1hi monocytes in both acute and chronic injured livers were all inhibited, and the enhanced hepatic expression of MCP-1 was suppressed. Cellular experiments demonstrated that Mat directly inhibited MCP-1 production in both nonparenchymal cells and hepatic stellate cells derived from CCl4-injured livers. Transwell chemotaxis assays showed that Mat significantly inhibited the chemotactic activity of MCP-1. These results suggest that the anti-inflammatory and antifibrotic effects of Mat could be contributed, at least in part, to its prevention of Gr1hi monocyte infiltration into the injured livers and inhibition of MCP-1 production and activity. These findings extend our understanding of the mechanisms underlying the anti-inflammatory and antifibrotic effects of Mat.

  4. Effects of Fluoroquinolones on the Migration of Human Phagocytes through Chlamydia pneumoniae-Infected and Tumor Necrosis Factor Alpha-Stimulated Endothelial Cells

    Science.gov (United States)

    Uriarte, Silvia M.; Molestina, Robert E.; Miller, Richard D.; Bernabo, Jorge; Farinati, Alicia; Eiguchi, Kumiko; Ramirez, Julio A.; Summersgill, James T.

    2004-01-01

    The anti-inflammatory activities of three quinolones, levofloxacin, moxifloxacin, and gatifloxacin, were investigated with an in vitro model of transendothelial migration (TEM). Human umbilical vein endothelial cells (HUVEC) were seeded in Transwell inserts, treated with serial dilutions of antibiotics, infected with Chlamydia pneumoniae, or stimulated with tumor necrosis factor alpha (TNF-α). Neutrophils or monocytes were also preincubated with serial dilutions of each antibiotic. TEM was assessed by light microscopic examination of the underside of the polycarbonate membrane, and levels of interleukin-8 (IL-8) and monocyte chemotactic protein 1 (MCP-1) were measured by enzyme-linked immunosorbent assay. In HUVEC infected with C. pneumoniae or stimulated with TNF-α, all fluoroquinolones significantly decreased neutrophil and monocyte TEM, compared to antibiotic-free controls. Moxifloxacin and gatifloxacin produced a significant decrease in IL-8 in C. pneumoniae-infected and TNF-α-stimulated HUVEC; however, moxifloxacin was the only fluoroquinolone that produced a significant decrease in MCP-1 levels under both conditions. Results from this study indicate similarities in the anti-inflammatory activities of these fluoroquinolones, although no statistically significant decrease in chemokine secretion was observed when levofloxacin was used. Mechanisms of neutrophil and monocyte TEM inhibition by fluoroquinolone antibiotics are unknown but may be partially due to inhibition of IL-8 and MCP-1 production, respectively. PMID:15215106

  5. Differential effects of Th1, monocyte/macrophage and Th2 cytokine mixtures on early gene expression for glial and neural-related molecules in central nervous system mixed glial cell cultures: neurotrophins, growth factors and structural proteins

    Directory of Open Access Journals (Sweden)

    Nedelkoska Liljana

    2007-12-01

    Full Text Available Abstract Background In multiple sclerosis, inflammatory cells are found in both active and chronic lesions, and it is increasingly clear that cytokines are involved directly and indirectly in both formation and inhibition of lesions. We propose that cytokine mixtures typical of Th1 or Th2 lymphocytes, or monocyte/macrophages each induce unique molecular changes in glial cells. Methods To examine changes in gene expression that might occur in glial cells exposed to the secreted products of immune cells, we have used gene array analysis to assess the early effects of different cytokine mixtures on mixed CNS glia in culture. We compared the effects of cytokines typical of Th1 and Th2 lymphocytes and monocyte/macrophages (M/M on CNS glia after 6 hours of treatment. Results In this paper we focus on changes with potential relevance for neuroprotection and axon/glial interactions. Each mixture of cytokines induced a unique pattern of changes in genes for neurotrophins, growth and maturation factors and related receptors; most notably an alternatively spliced form of trkC was markedly downregulated by Th1 and M/M cytokines, while Th2 cytokines upregulated BDNF. Genes for molecules of potential importance in axon/glial interactions, including cell adhesion molecules, connexins, and some molecules traditionally associated with neurons showed significant changes, while no genes for myelin-associated genes were regulated at this early time point. Unexpectedly, changes occurred in several genes for proteins initially associated with retina, cancer or bone development, and not previously reported in glial cells. Conclusion Each of the three cytokine mixtures induced specific changes in gene expression that could be altered by pharmacologic strategies to promote protection of the central nervous system.

  6. Correlation of urinary monocyte chemo-attractant protein-1 with other parameters of renal injury in type-II diabetes mellitus

    Directory of Open Access Journals (Sweden)

    Ibrahim Salwa

    2008-01-01

    Full Text Available Diabetic nephropathy (DN is the leading cause of end-stage renal disease in the western world. Increased number of interstitial macrophages has been observed in biopsies from patients with DN. Monocyte chemo-attractant protein-1 (MCP-1 is the strongest known chemo-tactic factor for monocytes and is upregulated in DN. We examined urinary levels of MCP-1 in patients with type-2 diabetes mellitus (DM to assess its possible correlation with other para-meters of renal injury. The urinary MCP-1 level was assessed in 75 patients with type-2 DM (25 patients each with no microalbuminuria, with macroalbuminuria and, with renal impairment and compared them with matched healthy control subjects. The HbA1c and estimated glomerular fil-tration rate (eGFR derived from the abbreviated Modification of Diet in Renal Disease (MDRD equation were examined in the study groups in relation to the urinary MCP-1. The urinary MCP-1 level was significantly higher in patients with micro and macroalbuminuria (167.41 ± 50.23 and 630.87 ± 318.10 ng/gm creatinine respectively as compared with normoalbuminuric patients and healthy controls (63.85 ± 21.15 and 61.50 ± 24.81 ng/gm creatinine, p< 0.001. MCP-1 correlated positively with urine albumin/creatinine ratio (ACR (r= 0.75, p< 0.001, HbA1c (r= 0.55, p< 0.001 and inversely with eGFR (r=-0.60, p< 0.001. Our findings suggest that hyperglycemia is associated with increased urinary levels of MCP-1 that is closely linked to renal damage as reflected by proteinuria and eGFR levels. Collectively, these findings suggest that MCP-1 is in-volved in the pathogenesis of diabetic nephropathy through its various stages.

  7. Effect of Erythropoietin on Proinflammatory Factors of Human Monocytes and Its Mechanisms%红细胞生成素对人单核细胞前炎症因子的影响及机理

    Institute of Scientific and Technical Information of China (English)

    韩潇; 武永吉; 周道斌; 许彩民; 杨洋; 段明辉; 汪玄; 张洁萍; 赵永强; 沈悌

    2011-01-01

    红细胞生成素(erythropoietin,EPO)是治疗慢性病贫血(anemia of chronic disease,ACD)的主要药物,通过刺激造血、抑制hepcidin和前炎症因子而改善贫血.近来发现单核细胞是hepcidin的另一来源,EPO能降低IL-6诱导的hepcidin,推测EPO可能通过降低IL-6进而抑制hepcidin的间接途径.然而,EPO降低单核细胞IL-6相应的分子生物学机制还不清楚.本研究探讨EPO对单核细胞前炎症因子的作用及其分子学机制.采用实时定量PCR 检测IL-6 mRNA和TNF-α mRNA表达,Western blot方法检测PARP-1信号分子的蛋白水平.采用1μg/ml脂多糖(lipopolysaccharide,LPS)刺激THP-1单核细胞,观察EPO不同浓度(0.5,1,2,5,10 U/ml)和作用时间(0,3,6,12,24小时)对THP-1单核细胞IL-6 mRNA、TNF-α mRNA以及PARP-1蛋白的抑制作用.加用1μg/ml或5μg/ml EPO受体(EPOR)抗体和/或3-氨基苯甲酰胺(3AB,PARP-1抑制剂),观察其对EPO的拮抗作用以及对PARP-1信号分子的影响.结果表明,1μg/ml LPS可以明显促进THP-1单核细胞IL-6和TNF-αmRNA表达.EPO可抑制LPS诱导的IL-6和TNF-αmRNA表达,且呈浓度和时间依赖性:对于IL-6 mRNA,2 U/ml EPO作用6小时的抑制作用最明显;对于TNF-αmRNA,10 U/ml EPO作用3小时的抑制作用最明显.研究发现,LPS诱导IL-6 mRNA表达升高的同时PARP-1蛋白水平也明显增加,EPO抑制IL-6 mRNA表达的同时PARP-1蛋白也下降,且2 U/ml EPO 作用6小时对IL-6和PARP-1蛋白均有明显抑制.3AB是PARP-1的直接抑制剂,EPO受体的抗体与3AB相似,可拮抗EPO对IL-6的抑制作用.结论:EPO能够抑制单核细胞IL-6和TNF-α表达,EPO可能通过降低PARP-1水平抑制IL-6的表达.%Erythropoietin (EPO) is the major means of treating anemia of chronic disease (ACD) through stimulating hematopoiesis, inhibiting hepcidin and decreasing proinflammatory factors. Recently, it has been found that monocytes are another source of hepcidn. EPO can reduce the hepcidin stimulated by IL-6 in

  8. Automated Chemotactic Sorting and Single-cell Cultivation of Microbes using Droplet Microfluidics

    National Research Council Canada - National Science Library

    Dong, Libing; Chen, Dong-Wei; Liu, Shuang-Jiang; Du, Wenbin

    2016-01-01

    ...; in the second part, chemotactic cells from the sample were separated, and mixed with culture media to form nanoliter droplets for encapsulation, cultivation, enumeration, and recovery of single cells...

  9. Monocyte-induced downregulation of nitric oxide synthase in cultured aortic endothelial cells.

    Science.gov (United States)

    Marczin, N; Antonov, A; Papapetropoulos, A; Munn, D H; Virmani, R; Kolodgie, F D; Gerrity, R; Catravas, J D

    1996-09-01

    Since endothelium-dependent vasodilation is altered in atherosclerosis and enhanced monocyte/endothelial interactions are implicated in early atherosclerosis, we evaluated the effects of monocytes on the endothelial nitric oxide (NO) pathway by estimating release of biologically active NO from cultured endothelial cells and levels of constitutive NO synthase (ecNOS). NO release was estimated in a short-term bioassay using endothelial cell-induced cGMP accumulation in vascular smooth muscle (SM) cells. Exposure of SM cells to porcine aortic endothelial cells (PAECs) and human aortic endothelial cells (HAECs) produced large increases in SM cGMP content; this increase was prevented by NG-nitro-L-arginine methyl ester, the inhibitor of endothelial NOS. Confluent monolayers of PAECs and HAECs cocultured with monocytes also stimulated SM cGMP formation; however, NO release from these cultures was attenuated in a coculture time (2 to 48 hours)- and monocyte concentration (20 to 200 x 10(3) per well)-dependent manner. This effect of monocyte adhesion appeared to be selective for NO release since other biochemical pathways, such as atriopeptin-and isoproterenol-induced cyclic nucleotide accumulation within the endothelial cells, were not altered by monocytes. The effects of adherent monocytes on NO release were mimicked by monocyte-derived cytokines tumor necrosis factor (TNF)-alpha and interleukin (IL)-1 alpha. Furthermore, the conditioned medium of monocytes contained significant quantities of these cytokines. Conditioned medium, as well as monocytes physically separated from the endothelial cells, attenuated NO release, suggesting that soluble factors may mediate the effects of monocytes. An IL-1 beta neutralizing antibody fully prevented the NO dysfunction in response to directly adherent monocytes. Superoxide dismutase, catalase, 4,5-dihydroxy-1,3-benzene disulfonic acid (Tiron), and exogenous L-arginine failed to improve NO release, suggesting that oxidant stress

  10. Chemotactic Activity on Human Neutrophils to Streptococcus mutans

    Directory of Open Access Journals (Sweden)

    Tetiana Haniastuti

    2013-07-01

    Full Text Available Objective: The aim of this study was to evaluate chemotactic activity o neutrophil to S. mutans. Chemotaxis assay was performed in blind well chambers. Materials and Methods: Hanks balanced salt solution (HBSS containing 106 S. mutans,  108 S. mutans, 10-8 M fMLP, or HBSS alone were placed in the lower wells of the chamber and covered with polycorbonate membrane filter. Neutrophils suspension (2x105 cells was then placed in the upper compartment. After incubation for 60 mins at 37ºC in a humidified atmosphere with 5% CO2, the filters were removed and stained with Giemsa. Result: ANOVA revealed statistically significant differences among groups (p<0.05, indicating that S. mutans induced neutrophils chemotaxis. The number of neutrophils migration in response to 108 S. mutans and 106 S. mutans were signifiantly greater compared to fMLP (p<0.05. Conclusion: S. mutans may activate human neutrophils, resulting in the chemotaxis of the neutrophils.DOI: 10.14693/jdi.v16i2.99

  11. Optimal noise filtering in the chemotactic response of Escherichia coli.

    Directory of Open Access Journals (Sweden)

    Burton W Andrews

    2006-11-01

    Full Text Available Information-carrying signals in the real world are often obscured by noise. A challenge for any system is to filter the signal from the corrupting noise. This task is particularly acute for the signal transduction network that mediates bacterial chemotaxis, because the signals are subtle, the noise arising from stochastic fluctuations is substantial, and the system is effectively acting as a differentiator which amplifies noise. Here, we investigated the filtering properties of this biological system. Through simulation, we first show that the cutoff frequency has a dramatic effect on the chemotactic efficiency of the cell. Then, using a mathematical model to describe the signal, noise, and system, we formulated and solved an optimal filtering problem to determine the cutoff frequency that bests separates the low-frequency signal from the high-frequency noise. There was good agreement between the theory, simulations, and published experimental data. Finally, we propose that an elegant implementation of the optimal filter in combination with a differentiator can be achieved via an integral control system. This paper furnishes a simple quantitative framework for interpreting many of the key notions about bacterial chemotaxis, and, more generally, it highlights the constraints on biological systems imposed by noise.

  12. Differential expression of monocyte surface markers among TB patients with diabetes co-morbidity.

    Science.gov (United States)

    Stew, Samuel S; Martinez, Perla J; Schlesinger, Larry S; Restrepo, Blanca I

    2013-12-01

    The expression of monocyte surface markers was compared between tuberculosis patients with and without type 2 diabetes (DM2). DM2 was associated with increased CCR2 expression, which may restrain monocyte traffic to the lung. Other host factors associated with baseline monocyte changes were older age (associated with lower CD11b) and obesity (associated with higher RAGE). Given that DM2 patients are more likely to be older and obese, their monocytes are predicted to be altered in function in ways that affect their interaction with Mycobacterium tuberculosis.

  13. Urease-independent chemotactic responses of Helicobacter pylori to urea, urease inhibitors, and sodium bicarbonate.

    OpenAIRE

    Mizote, T; Yoshiyama, H; T. Nakazawa

    1997-01-01

    Helicobacter pylori CPY3401 and an isogenic urease-negative mutant, HPT73, showed chemotactic responses to urea, flurofamide (a potent urease inhibitor), and sodium bicarbonate. Since urea and sodium bicarbonate are secreted through the gastric epithelial surface and hydrolysis of urea by urease on the bacterial surface is essential for colonization, the chemotactic response of H. pylori may be crucial for its colonization and persistence in the stomach.

  14. Primary 1,25-dihydroxyvitamin D3 response of the interleukin 8 gene cluster in human monocyte- and macrophage-like cells.

    Directory of Open Access Journals (Sweden)

    Jussi Ryynänen

    Full Text Available Genome-wide analysis of vitamin D receptor (VDR binding sites in THP-1 human monocyte-like cells highlighted the interleukin 8 gene, also known as chemokine CXC motif ligand 8 (CXCL8. CXCL8 is a chemotactic cytokine with important functions during acute inflammation as well as in the context of various cancers. The nine genes of the CXCL cluster and the strong VDR binding site close to the CXCL8 gene are insulated from neighboring genes by CCCTC-binding factor (CTCF binding sites. Only CXCL8, CXCL6 and CXCL1 are expressed in THP-1 cells, but all three are up-regulated primary 1,25-dihydroxyvitamin D3 (1,25(OH2D3 target genes. Formaldehyde-assisted isolation of regulatory elements sequencing analysis of the whole CXCL cluster demonstrated 1,25(OH2D3-dependent chromatin opening exclusively for the VDR binding site. In differentiated THP-1 cells the CXCL8 gene showed a 33-fold higher basal expression, but is together with CXCL6 and CXCL1 still a primary 1,25(OH2D3 target under the control of the same genomic VDR binding site. In summary, both in undifferentiated and differentiated THP-1 cells the genes CXCL8, CXCL6 and CXCL1 are under the primary control of 1,25(OH2D3 and its receptor VDR. Our observation provides further evidence for the immune-related functions of vitamin D.

  15. Ly6C- Monocytes Regulate Parasite-Induced Liver Inflammation by Inducing the Differentiation of Pathogenic Ly6C+ Monocytes into Macrophages.

    Directory of Open Access Journals (Sweden)

    Yannick Morias

    2015-05-01

    Full Text Available Monocytes consist of two well-defined subsets, the Ly6C+ and Ly6C- monocytes. Both CD11b+ myeloid cells populations have been proposed to infiltrate tissues during inflammation. While infiltration of Ly6C+ monocytes is an established pathogenic factor during hepatic inflammation, the role of Ly6C- monocytes remains elusive. Mice suffering experimental African trypanosome infection die from systemic inflammatory response syndrome (SIRS that is initiated by phagocytosis of parasites by liver myeloid cells and culminates in apoptosis/necrosis of liver myeloid and parenchymal cells that reduces host survival. C57BL/6 mice are considered as trypanotolerant to Trypanosoma congolense infection. We have reported that in these animals, IL-10, produced among others by myeloid cells, limits the liver damage caused by pathogenic TNF-producing Ly6C+ monocytes, ensuring prolonged survival. Here, the heterogeneity and dynamics of liver myeloid cells in T. congolense-infected C57/BL6 mice was further dissected. Moreover, the contribution of Ly6C- monocytes to trypanotolerance was investigated. By using FACS analysis and adoptive transfer experiments, we found that the accumulation of Ly6C- monocytes and macrophages in the liver of infected mice coincided with a drop in the pool of Ly6C+ monocytes. Pathogenic TNF mainly originated from Ly6C+ monocytes while Ly6C- monocytes and macrophages were major and equipotent sources of IL-10 within myeloid cells. Moreover, Nr4a1 (Nur77 transcription factor-dependent Ly6C- monocytes exhibited IL-10-dependent and cell contact-dependent regulatory properties contributing to trypanotolerance by suppressing the production of TNF by Ly6C+ monocytes and by promoting the differentiation of the latter cells into macrophages. Thus, Ly6C- monocytes can dampen liver damage caused by an extensive Ly6C+ monocyte-associated inflammatory immune response in T. congolense trypanotolerant animals. In a more general context, Ly6C- or Ly6C

  16. STAT3 activation in monocytes accelerates liver cancer progression

    Directory of Open Access Journals (Sweden)

    Wu Wen-Yong

    2011-12-01

    Full Text Available Abstract Background Signal transducer and activator of transcription 3 (STAT3 is an important transcription factor ubiquitously expressed in different cell types. STAT3 plays an essential role in cell survival, proliferation, and differentiation. Aberrantly hyper-activated STAT3 signaling in cancer cells and in the tumor microenvironment has been detected in a wide variety of human cancers and is considered an important factor for cancer initiation, development, and progression. However, the role of STAT3 activation in monocytes in the development of HCC has not been well understood. Methods Immunohistochemical analysis of phosphorylated STAT3 was performed on tissue microarray from HCC patients. Using a co-culture system in vivo, HCC cell growth was determined by the MTT assay. In vivo experiments were conducted with mice given diethylinitrosamine (DEN, which induces HCC was used to investigate the role of STAT3 expression in monocytes on tumor growth. Real-time PCR was used to determine the expression of cell proliferation and cell arrest associated genes in the tumor and nontumor tissue from liver. Results Phosphorylated STAT3 was found in human hepatocellular carcinoma tissue samples and was expressed in tumor cells and also in monocytes. Phosphorylated STAT3 expression in monocyte was significantly correlated to advanced clinical stage of HCC and a poor prognosis. Using a co-culture system in vivo, monocytes promoted HCC cell growth via the IL-6/STAT3 signaling pathway. The STAT3 inhibitor, NSC 74859, significantly suppressed tumor growth in vivo in mice with diethylinitrosamine (DEN-induced HCC. In this animal model, blockade of STAT3 with NSC 74859 induced tumor cell apoptosis, while inhibiting both tumor cells and monocytes proliferation. Furthermore, NSC 74859 treatment suppressed cancer associated inflammation in DEN-induce HCC. Conclusion Our data suggest constitutively activated STAT3 monocytes promote liver tumorigenesis in clinical

  17. Human sperm pattern of movement during chemotactic re-orientation towards a progesterone source

    Institute of Scientific and Technical Information of China (English)

    Cecilia Soledad Blengini; Maria Eugenia Teves; Diego Rafael Unates; Hector Alejandro Guidobaldi; Laura Virginia Gatica; Laura Cecilia Giojalas

    2011-01-01

    @@ Human spermatozoa may chemotactically find out the egg by following an increasing gradient of attractant molecules.Although human spermatozoa have been observed to show several of the physiological characteristics of chemotaxis,the chemotactic pattern of movement has not been easy to describe.However,it is apparent that chemotactic cells may be identified while returning to the attractant source.This study characterizes the pattern of movement of human spermatozoa during chemotactic re-orientation towards a progesterone source,which is a physiological attractant candidate.By means of videomicroscopy and image analysis,a chemotactic pattern of movement was identified as the spermatozoon returned towards the source of a chemotactic concentration of progesterone (10 pmol l-1).First,as a continuation of its original path,the spermatozoon swims away from the progesterone source with linear movement and then turns back with a transitional movement that can be characterized by an increased velocity and decreased linearity.This sperm behaviour may help the spermatozoon to re-orient itself towards a progesterone source and may be used to identify the few cells that are undergoing chemotaxis at a given time.

  18. Monocyte chemoattractant protein-1 induces endothelial cell apoptosis in vitro through a p53-dependent mitochondrial pathway

    Institute of Scientific and Technical Information of China (English)

    Xuan Zhang; Xiping Liu; Huifeng Shang; Yan Xu; Minzhang Qian

    2011-01-01

    The cystine-cystine (CC) chemokine monocyte chemoattractant protein-1 (MCP-1) has been established playing a pathogenic role in the development of atherosclerosis due to its chemotactic ability of leading monocytes to locate to subendothelia.Recent studies have revealed more MCP-1 functions other than chemotaxis.Here we reported that various concentrations (0.1-100 ng/ml) of MCP-1 induced human umbilical vein endothelial cell (HUVEC) strain CRL-1730 apoptosis,caspase-9 activation,and a couple of mitochondrial alterations.Moreover,MCP-1 upregulated p53 expression of HUVECs and the p53-specific inhibitor pifithrin-α(PFTα) rescued the MCP-1-induced apoptosis of HUVECs.Furthermore,PKC (protein kinase C) activation or inhibition might also affect HUVECs apoptosis induced by MCP-1.These findings together demonstrate that MCP-1 exerts direct proapoptotic effects on HUVECs in vitro via a p53-dependent mitochondrial pathway.

  19. RP463: a stabilized technetium-99m complex of a hydrazino nicotinamide derivatized chemotactic peptide for infection imaging.

    Science.gov (United States)

    Edwards, D S; Liu, S; Ziegler, M C; Harris, A R; Crocker, A C; Heminway, S J; Barrett, J A; Bridger, G J; Abrams, M J; Higgins, J D

    1999-01-01

    A HYNIC-conjugated chemotactic peptide (fMLFK-HYNIC) was labeled with (99m)Tc using tricine and TPPTS as coligands. The combination of fMLFK-HYNIC, tricine, and TPPTS with (99m)Tc produced a ternary ligand complex [(99m)Tc(fMLFK-HYNIC)(tricine)(TPPTS)] (RP463). RP463 was synthesized either in two steps, in which the binary ligand complex [(99m)Tc(fMLFK-HYNIC)(tricine)(2)] (RP469) was formed first and then reacted with TPPTS, or in one step by direct reduction of [(99m)Tc]pertechnetate with stannous chloride in the presence of fMLFK-HYNIC, tricine, and TPPTS. The radiolabeling yield for RP463 was usually >/=90% using 10 microg of fMLFK-HYNIC and 100 mCi of [(99m)Tc]pertechnetate. Unlike RP469, which decomposed rapidly in the absence of excess tricine coligand, RP463 was stable in solution for at least 6 h. [(99)Tc]RP463 was prepared and characterized by HPLC and electrospray mass spectrometry. In an in vitro assay, [(99)Tc]RP463 showed an IC(50) of 2 nM against binding of [(3)H]fMLF to receptors on PMNs. [(99)Tc]RP463 also induces effectively the superoxide release of polymorphonuclear leukocytes (PMNs) with an EC(50) value of 0.2 +/- 0.2 nM. The localization of RP463 in the infection foci was assessed in a rabbit infection model. RP463 was cleared from the blood faster than RP469 and was excreted mainly through the renal system. As a result of rapid blood clearance and increased uptake, the target-to-background ratios continuously increased from 1.5 +/- 0.2 at 15 min postinjection to 7.5 +/- 0.4 at 4 h postinjection. Visualization of the infected area could be as early as 2 h. A transient decrease in white blood cell count of 35% was observed during the first 30 min after injection of the HPLC-purified RP463 in the infected rabbit. This suggests that future research in this area should focus on developing highly potent antagonists for chemotactic peptide receptor or other receptors on PMNs and monocytes.

  20. Lipoteichoic acid from Lactobacillus plantarum inhibits the expression of platelet-activating factor receptor induced by Staphylococcus aureus lipoteichoic acid or Escherichia coli lipopolysaccharide in human monocyte-like cells.

    Science.gov (United States)

    Kim, Hangeun; Jung, Bong Jun; Jeong, Jihye; Chun, Honam; Chung, Dae Kyun

    2014-08-01

    Platelet-activating factor receptor (PAFR) plays an important role in bacterial infection and inflammation. We examined the effect of the bacterial cell wall components lipopolysaccharide (LPS) and lipoteichoic acid (LTA) from Lactobacillus plantarum (pLTA) and Staphylococcus aureus (aLTA) on PAFR expression in THP-1, a monocyte-like cell line. LPS and aLTA, but not pLTA, significantly increased PAFR expression, whereas priming with pLTA inhibited LPSmediated or aLTA-mediated PAFR expression. Expression of Toll-like receptor (TLR) 2 and 4, and CD14 increased with LPS and aLTA treatments, but was inhibited by pLTA pretreatment. Neutralizing antibodies against TLR2, TLR4, and CD14 showed that these receptors were important in LPS-mediated or aLTA-mediated PAFR expression. PAFR expression is mainly regulated by the nuclear factor kappa B signaling pathway. Blocking PAF binding to PAFR using a PAFR inhibitor indicated that LPS-mediated or aLTA-mediated PAF expression affected TNF-α production. In the mouse small intestine, pLTA inhibited PAFR, TLR2, and TLR4 expression that was induced by heat-labile toxin. Our data suggested that pLTA has an anti-inflammatory effect by inhibiting the expression of PAFR that was induced by pathogenic ligands.

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

    Science.gov (United States)

    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.

  2. Neutrophil activation by Candida glabrata but not Candida albicans promotes fungal uptake by monocytes.

    Science.gov (United States)

    Duggan, Seána; Essig, Fabian; Hünniger, Kerstin; Mokhtari, Zeinab; Bauer, Laura; Lehnert, Teresa; Brandes, Susanne; Häder, Antje; Jacobsen, Ilse D; Martin, Ronny; Figge, Marc Thilo; Kurzai, Oliver

    2015-09-01

    Candida albicans and Candida glabrata account for the majority of candidiasis cases worldwide. Although both species are in the same genus, they differ in key virulence attributes. Within this work, live cell imaging was used to examine the dynamics of neutrophil activation after confrontation with either C. albicans or C. glabrata. Analyses revealed higher phagocytosis rates of C. albicans than C. glabrata that resulted in stronger PMN (polymorphonuclear cells) activation by C. albicans. Furthermore, we observed differences in the secretion of chemokines, indicating chemotactic differences in PMN signalling towards recruitment of further immune cells upon confrontation with Candida spp. Supernatants from co-incubations of neutrophils with C. glabrata primarily attracted monocytes and increased the phagocytosis of C. glabrata by monocytes. In contrast, PMN activation by C. albicans resulted in recruitment of more neutrophils. Two complex infection models confirmed distinct targeting of immune cell populations by the two Candida spp.: In a human whole blood infection model, C. glabrata was more effectively taken up by monocytes than C. albicans and histopathological analyses of murine model infections confirmed primarily monocytic infiltrates in C. glabrata kidney infection in contrast to PMN-dominated infiltrates in C. albicans infection. Taken together, our data demonstrate that the human opportunistic fungi C. albicans and C. glabrata are differentially recognized by neutrophils and one outcome of this differential recognition is the preferential uptake of C. glabrata by monocytes.

  3. Polarization of migrating monocytic cells is independent of PI 3-kinase activity.

    Directory of Open Access Journals (Sweden)

    Silvia Volpe

    Full Text Available BACKGROUND: Migration of mammalian cells is a complex cell type and environment specific process. Migrating hematopoietic cells assume a rapid amoeboid like movement when exposed to gradients of chemoattractants. The underlying signaling mechanisms remain controversial with respect to localization and distribution of chemotactic receptors within the plasma membrane and the role of PI 3-kinase activity in cell polarization. METHODOLOGY/PRINCIPAL FINDINGS: We present a novel model for the investigation of human leukocyte migration. Monocytic THP-1 cells transfected with the alpha(2A-adrenoceptor (alpha(2AAR display comparable signal transduction responses, such as calcium mobilization, MAP-kinase activation and chemotaxis, to the noradrenaline homologue UK 14'304 as when stimulated with CCL2, which binds to the endogenous chemokine receptor CCR2. Time-lapse video microscopy reveals that chemotactic receptors remain evenly distributed over the plasma membrane and that their internalization is not required for migration. Measurements of intramolecular fluorescence resonance energy transfer (FRET of alpha(2AAR-YFP/CFP suggest a uniform activation of the receptors over the entire plasma membrane. Nevertheless, PI 3-kinase activation is confined to the leading edge. When reverting the gradient of chemoattractant by moving the dispensing micropipette, polarized monocytes--in contrast to neutrophils--rapidly flip their polarization axis by developing a new leading edge at the previous posterior side. Flipping of the polarization axis is accompanied by re-localization of PI-3-kinase activity to the new leading edge. However, reversal of the polarization axis occurs in the absence of PI 3-kinase activation. CONCLUSIONS/SIGNIFICANCE: Accumulation and internalization of chemotactic receptors at the leading edge is dispensable for cell migration. Furthermore, uniformly distributed receptors allow the cells to rapidly reorient and adapt to changes in the

  4. Prognostic value of preoperative peripheral monocyte count in patients with hepatocellular carcinoma after liver transplantation.

    Science.gov (United States)

    Ren, Qing-Qi; Fu, Shun-Jun; Zhao, Qiang; Guo, Zhi-Yong; Ji, Fei; Chen, Mao-Gen; Wu, Lin-Wei; He, Xiao-Shun

    2016-07-01

    Prognostic value of peripheral monocyte, as a member of inflammatory cells, was widely being investigated. The aim of this study was to evaluate the prognostic value of preoperative peripheral blood monocyte count for hepatocellular carcinoma (HCC) patients who underwent liver transplantation (LT) and the relationship between monocyte count and tumor-related characteristics. We retrospectively analyzed the clinical data of 101 HCC patients after LT. Preoperative monocyte count and demographic, clinical, and pathologic data were analyzed. The optimal cutoff value of monocyte count was 456/mm(3), with the sensitivity and specificity of 69.4 and 61.5 %, respectively. Elevated preoperative peripheral blood monocyte count was significantly associated with large tumor size. The 1-, 3-, and 5-year disease-free survival (DFS) (80.9, 70.1, and 53.3 % vs 55.1, 38.7, and 38.7 %, P = 0.007) and overall survival (OS) rates (95.7, 76.6, and 64.8 % vs 72.2, 44.1, and 36.1 %, P = 0.002) of HCC patients in the peripheral blood monocyte count ≤456/mm(3) group were higher than those in the peripheral blood monocyte count >456/mm(3) group. In conclusion, elevated preoperative peripheral blood monocyte count was significantly associated with advanced tumor stage and it can be considered as a prognostic factor for HCC patients after LT.

  5. Nicotinamide downregulates gene expression of interleukin-6, interleukin-10, monocyte chemoattractant protein-1, and tumour necrosis factor-α gene expression in HaCaT keratinocytes after ultraviolet B irradiation.

    Science.gov (United States)

    Monfrecola, G; Gaudiello, F; Cirillo, T; Fabbrocini, G; Balato, A; Lembo, S

    2013-03-01

    Ultraviolet (UV) radiation has profound effects on human skin, causing sunburn, inflammation, cellular-tissue injury, cell death, and skin cancer. Most of these effects are mediated by a number of cytokines produced by keratinocytes. In this study we investigated whether nicotinamide (NCT), the amide form of vitamin B3, might have a protective function in reducing the expression of interleukin (IL)-1β, IL-6, IL-8, IL-10, monocyte chemoattractant protein (MCP)-1 and tumour necrosis factor (TNF)-α in UV-irradiated keratinocytes. HaCaT cells were treated with UVB in the presence or absence of NCT, and cytokine mRNA levels were examined by quantitative real-time PCR. NCT significantly downregulated IL-6, IL-10, MCP-1 and TNF-α mRNA expression, whereas it did not exert any significant effect on IL-1β or IL-8 expression. Because of its ability to decrease these cytokine mediators after UV exposure, NCT is a possible therapy to improve or prevent conditions induced or aggravated by UV light.

  6. Effect of selective phosphodiesterase inhibitors on the rat eosinophil chemotactic response in vitro

    Directory of Open Access Journals (Sweden)

    Alessandra C Alves

    1997-12-01

    Full Text Available In the present study, we have performed a comparative analysis of the effect of selective inhibitors of phosphodiesterase (PDE type III, IV and V on eosinophil chemotaxis triggered by platelet activating factor (PAF and leukotriene B4 (LTB4 in vitro. The effect of the analogues N6-2'-O-dibutyryladenosine 3':5' cyclic monophosphate (Bt2 cyclic AMP and N2-2'-O- dibutyrylguanosine 3':5' cyclic monophosphate (Bt2 cyclic GMP has also been determined. The eosinophils were obtained from the peritoneal cavity of naive Wistar rats and purified in discontinuous Percoll gradients to 85-95% purity. We observed that pre-incubation of eosinophils with the PDE type IV inhibitor rolipram suppressed the chemotactic response triggered by PAF and LTB4, in association with an increase in the intracellular levels of cyclic AMP. In contrast, neither zaprinast (type V inhibitor nor type III inhibitors milrinone and SK&F 94836 affected the eosinophil migration. Only at the highest concentration tested did the analogue Bt2 cyclic AMP suppress the eosinophil chemotaxis, under conditions where Bt2 cyclic GMP was ineffective. We have concluded that inhibition of PDE IV, but not PDE III or V, was able to block the eosinophil chemotaxis in vitro, suggesting that the suppressive activity of selective PDE IV inhibitors on tissue eosinophil accumulation may, at least, be partially dependent on their ability to directly inhibit the eosinophil migration.

  7. Circulating monocytes from healthy individuals and COPD patients

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    Piitulainen Eeva

    2003-09-01

    Full Text Available Abstract Background Chronic obstructive pulmonary disease (COPD is characterized by incompletely reversible airflow obstruction associated with inflammation in which monocytes/macrophages are the predominant inflammatory cells. The only known genetic factor related to COPD is inherited PiZZ deficiency of α1-antitrypsin (AAT, an inhibitor of serine proteases. Methods We investigated the basal and LPS-stimulated release of pro-inflammatory molecules from blood monocytes isolated from age and gender matched healthy (n = 30 and COPD (n = 20 individuals with and without AAT deficiency. Results After 18 h of cell culture the basal release of MMP-9 was 2.5-fold, p Conclusions The basal and LPS-stimulated secretion of specific pro-inflammatory molecules from circulating monocytes differs between healthy and COPD subjects. These findings may be valuable for further studies on the mechanisms involved in recruitment and activation of inflammatory cells in COPD.

  8. Enhanced Retention of Chemotactic Bacteria in a Pore Network with Residual NAPL Contamination.

    Science.gov (United States)

    Wang, Xiaopu; Lanning, Larry M; Ford, Roseanne M

    2016-01-01

    Nonaqueous-phase liquid (NAPL) contaminants are difficult to eliminate from natural aquifers due, in part, to the heterogeneous structure of the soil. Chemotaxis enhances the mixing of bacteria with contaminant sources in low-permeability regions, which may not be readily accessible by advection and dispersion alone. A microfluidic device was designed to mimic heterogeneous features of a contaminated groundwater aquifer. NAPL droplets (toluene) were trapped within a fine pore network, and bacteria were injected through a highly conductive adjacent macrochannel. Chemotactic bacteria (Pseudomonas putida F1) exhibited greater accumulation near the pore network at 0.5 m/day than both the nonchemotactic control and the chemotactic bacteria at a higher groundwater velocity of 5 m/day. Chemotactic bacteria accumulated in the vicinity of NAPL droplets, and the accumulation was 15% greater than a nonchemotactic mutant. Indirect evidence showed that chemotactic bacteria were retained within the contaminated low-permeability region longer than nonchemotactic bacteria at 0.25 m/day. This retention was diminished at 5 m/day. Numerical solutions of the bacterial-transport equations were consistent with the experimental results. Because toluene is degraded by P. putida F1, the accumulation of chemotactic bacteria around NAPL sources is expected to increase contaminant consumption and improve the efficiency of bioremediation.

  9. Enhanced lentiviral transduction of monocyte-derived dendritic cells in the presence of conditioned medium from dying monocytes.

    Science.gov (United States)

    Masurier, C; Boutin, S; Veron, P; Bernard, J; Danos, O; Davoust, J

    2007-02-01

    Lentiviral vectors (LVs) are attractive vehicles for the transduction of human dendritic cells (DCs) in order to mobilize their endogenous antigen presentation pathways. We analyzed here how to improve the efficiency of LV transduction, which we performed at the initial stages of the differentiation of purified monocytes into dendritic cells (Mo-DCs). Using LVs pseudotyped with the vesicular stomatitis virus envelope G glycoprotein (VSV-G), we found that a conditioned medium derived from dying monocytes (MCM) improved by 2- to 10- fold the proportion of transduced Mo-DCs. This enhanced transduction efficiency requires the presence of MCM during the initial stage of LV transduction and does not affect the phenotype and antigen presentation function of terminally differentiated Mo-DCs. Importantly, we found that MCM derived from a human acute monocytic leukemia cell line, THP-1, was equally effective. The MCM activity was heat stable (56 degrees C) and was present in the soluble fraction after high-speed centrifugation. Altogether our results show that a soluble factor present in dying monocyte cultures can replace advantageously facilitating agents such as Polybrene, to achieve high LV transductions levels. This protocol can be performed with autologous monocytes and is therefore applicable in clinical settings.

  10. TRAIL+ monocytes and monocyte-related cells cause lung damage and thereby increase susceptibility to influenza-Streptococcus pneumoniae coinfection.

    Science.gov (United States)

    Ellis, Gregory T; Davidson, Sophia; Crotta, Stefania; Branzk, Nora; Papayannopoulos, Venizelos; Wack, Andreas

    2015-09-01

    Streptococcus pneumoniae coinfection is a major cause of influenza-associated mortality; however, the mechanisms underlying pathogenesis or protection remain unclear. Using a clinically relevant mouse model, we identify immune-mediated damage early during coinfection as a new mechanism causing susceptibility. Coinfected CCR2(-/-) mice lacking monocytes and monocyte-derived cells control bacterial invasion better, show reduced epithelial damage and are overall more resistant than wild-type controls. In influenza-infected wild-type lungs, monocytes and monocyte-derived cells are the major cell populations expressing the apoptosis-inducing ligand TRAIL. Accordingly, anti-TRAIL treatment reduces bacterial load and protects against coinfection if administered during viral infection, but not following bacterial exposure. Post-influenza bacterial outgrowth induces a strong proinflammatory cytokine response and massive inflammatory cell infiltrate. Depletion of neutrophils or blockade of TNF-α facilitate bacterial outgrowth, leading to increased mortality, demonstrating that these factors aid bacterial control. We conclude that inflammatory monocytes recruited early, during the viral phase of coinfection, induce TRAIL-mediated lung damage, which facilitates bacterial invasion, while TNF-α and neutrophil responses help control subsequent bacterial outgrowth. We thus identify novel determinants of protection versus pathology in influenza-Streptococcus pneumoniae coinfection.

  11. Arctigenin suppresses transforming growth factor-β1-induced expression of monocyte chemoattractant protein-1 and the subsequent epithelial-mesenchymal transition through reactive oxygen species-dependent ERK/NF-κB signaling pathway in renal tubular epithelial cells.

    Science.gov (United States)

    Li, A; Wang, J; Zhu, D; Zhang, X; Pan, R; Wang, R

    2015-01-01

    Transforming growth factor-β1 (TGF-β1) induces expression of the proinflammatory and profibrotic cytokine monocyte chemoattractant protein-1 (MCP-1) in tubular epithelial cells (TECs) and thereby contributes to the tubular epithelial-mesenchymal transition (EMT), which in turn leads to the progression of tubulointerstitial inflammation into tubulointerstitial fibrosis. Exactly how TGF-β1 causes MCP-1 overexpression and subsequent EMT is not well understood. Using human tubular epithelial cultures, we found that TGF-β1 upregulated the expression of reduced nicotinamide adenine dinucleotide phosphate oxidases 2 and 4 and their regulatory subunits, inducing the production of reactive oxygen species. These reactive species activated a signaling pathway mediated by extracellular signal-regulated kinase (ERK1/2) and nuclear factor-κB (NF-κB), which upregulated expression of MCP-1. Incubating cultures with TGF-β1 was sufficient to induce hallmarks of EMT, such as downregulation of epithelial marker proteins (E-cadherin and zonula occludens-1), induction of mesenchymal marker proteins (α-smooth muscle actin, fibronectin, and vimentin), and elevated cell migration and invasion in an EMT-like manner. Overexpressing MCP-1 in cells exposed to TGF-β1 exacerbated these EMT-like changes. Pretreating cells with the antioxidant and anti-inflammatory compound arctigenin (ATG) protected them against these TGF-β1-induced EMT-like changes; the compound worked by inhibiting the ROS/ERK1/2/NF-κB pathway to decrease MCP-1 upregulation. These findings suggest ATG as a new therapeutic candidate to inhibit or even reverse tubular EMT-like changes during progression to tubulointerstitial fibrosis, and they provide the first clues to how ATG may work.

  12. Sialoadhesin expressed on IFN-induced monocytes binds HIV-1 and enhances infectivity.

    Directory of Open Access Journals (Sweden)

    Hans Rempel

    Full Text Available BACKGROUND: HIV-1 infection dysregulates the immune system and alters gene expression in circulating monocytes. Differential gene expression analysis of CD14(+ monocytes from subjects infected with HIV-1 revealed increased expression of sialoadhesin (Sn, CD169, Siglec 1, a cell adhesion molecule first described in a subset of macrophages activated in chronic inflammatory diseases. METHODOLOGY/PRINCIPAL FINDINGS: We analyzed sialoadhesin expression on CD14(+ monocytes by flow cytometry and found significantly higher expression in subjects with elevated viral loads compared to subjects with undetectable viral loads. In cultured CD14(+ monocytes isolated from healthy individuals, sialoadhesin expression was induced by interferon-alpha and interferon-gamma but not tumor necrosis factor-alpha. Using a stringent binding assay, sialoadhesin-expressing monocytes adsorbed HIV-1 through interaction with the sialic acid residues on the viral envelope glycoprotein gp120. Furthermore, monocytes expressing sialoadhesin facilitated HIV-1 trans infection of permissive cells, which occurred in the absence of monocyte self-infection. CONCLUSIONS/SIGNIFICANCE: Increased sialoadhesin expression on CD14(+ monocytes occurred in response to HIV-1 infection with maximum expression associated with high viral load. We show that interferons induce sialoadhesin in primary CD14(+ monocytes, which is consistent with an antiviral response during viremia. Our findings suggest that circulating sialoadhesin-expressing monocytes are capable of binding HIV-1 and effectively delivering virus to target cells thereby enhancing the distribution of HIV-1. Sialoadhesin could disseminate HIV-1 to viral reservoirs during monocyte immunosurveillance or migration to sites of inflammation and then facilitate HIV-1 infection of permissive cells.

  13. Monocyte Activation by Necrotic Cells Is Promoted by Mitochondrial Proteins and Formyl Peptide Receptors

    Science.gov (United States)

    Crouser, Elliott D.; Shao, Guohong; Julian, Mark W.; Macre, Jennifer E.; Shadel, Gerald S.; Tridandapani, Susheela; Huang, Qin; Wewers, Mark D.

    2009-01-01

    Objective Necrotic cells evoke potent innate immune responses through unclear mechanisms. The mitochondrial fraction of the cell retains constituents of its bacterial ancestors, including N-formyl peptides, which are potentially immunogenic. Thus, we hypothesized that the mitochondrial fraction of the cell, particularly N-formyl peptides, contributes significantly to the activation of monocytes by necrotic cells. Design Human peripheral blood monocytes were incubated with necrotic cell fractions and mitochondrial proteins in order to investigate their potential for immune cell activation. Setting University medical center research laboratory. Subjects Healthy human adults served as blood donors. Measurements and Main Results Human blood monocyte activation was measured after treatment with cytosolic, nuclear and mitochondrial fractions of necrotic HepG2 cells or necrotic HepG2 cells depleted of N-formyl peptides [Rho(0) cells]. The specific role of the high affinity formyl peptide receptor (FPR) was then tested using specific pharmacological inhibitors and RNA-silencing. The capacity of mitochondrial N-formyl peptides to activate monocytes was confirmed using a synthetic peptide conforming to the N-terminus of mitochondrial NADH subunit 6. The results demonstrated that mitochondrial cell fractions most potently activated monocytes, and IL-8 was selectively released at low protein concentrations. Mitochondria from Rho(0) cells induced minimal monocyte IL-8 release, and specific pharmacological inhibitors and RNA-silencing confirmed that FPR contributes significantly to monocyte IL-8 responses to both necrotic cells and mitochondrial proteins. N-formyl peptides alone did not induce monocyte IL-8 release; whereas, the combination of mitochondrial N-formyl peptides and mitochondrial transcription factor A (TFAM) dramatically increased IL-8 release from monocytes. Likewise, HMGB1, the nuclear homologue of TFAM, did not induce monocyte IL-8 release unless combined with

  14. Collective Chemotactic Dynamics in the Presence of Self-Generated Fluid Flows

    CERN Document Server

    Lushi, Enkeleida; Shelley, Michael J

    2012-01-01

    In micro-swimmer suspensions locomotion necessarily generates fluid motion, and it is known that such flows can lead to collective behavior from unbiased swimming. We examine the complementary problem of how chemotaxis is affected by self-generated flows. A kinetic theory coupling run-and-tumble chemotaxis to the flows of collective swimming shows separate branches of chemotactic and hydrodynamic instabilities for isotropic suspensions, the first driving aggregation, the second producing increased orientational order in suspensions of "pushers" and maximal disorder in suspensions of "pullers". Nonlinear simulations show that hydrodynamic interactions can limit and modify chemotactically-driven aggregation dynamics. In puller suspensions the dynamics form aggregates that are mutually-repelling due to the non-trivial flows. In pusher suspensions chemotactic aggregation can lead to destabilizing flows that fragment the regions of aggregation.

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

    Energy Technology Data Exchange (ETDEWEB)

    Suzuki, Yuka; Tada-Oikawa, Saeko [Graduate School of Regional Innovation Studies, Mie University, Tsu (Japan); Ichihara, Gaku [Department of Occupational and Environmental Health, Nagoya University Graduate School of Medicine, Nagoya (Japan); Yabata, Masayuki; Izuoka, Kiyora [Graduate School of Regional Innovation Studies, Mie University, Tsu (Japan); Suzuki, Masako; Sakai, Kiyoshi [Nagoya City Public Health Research Institute, Nagoya (Japan); Ichihara, Sahoko, E-mail: saho@gene.mie-u.ac.jp [Graduate School of Regional Innovation Studies, Mie University, Tsu (Japan)

    2014-07-01

    Metal oxide nanoparticles are widely used in industry, cosmetics, and biomedicine. However, the effects of exposure to these nanoparticles on the cardiovascular system remain unknown. The present study investigated the effects of nanosized TiO{sub 2} and ZnO particles on the migration and adhesion of monocytes, which are essential processes in atherosclerogenesis, using an in vitro set-up of human umbilical vein endothelial cells (HUVECs) and human monocytic leukemia cells (THP-1). We also examined the effects of exposure to nanosized metal oxide particles on macrophage cholesterol uptake and foam cell formation. The 16-hour exposure to ZnO particles increased the level of monocyte chemotactic protein-1 (MCP-1) and induced the migration of THP-1 monocyte mediated by increased MCP-1. Exposure to ZnO particles also induced adhesion of THP-1 cells to HUVECs. Moreover, exposure to ZnO particles, but not TiO{sub 2} particles, upregulated the expression of membrane scavenger receptors of modified LDL and increased cholesterol uptake in THP-1 monocytes/macrophages. In the present study, we found that exposure to ZnO particles increased macrophage cholesterol uptake, which was mediated by an upregulation of membrane scavenger receptors of modified LDL. These results suggest that nanosized ZnO particles could potentially enhance atherosclerogenesis and accelerate foam cell formation. - Highlights: • Effects of metal oxide nanoparticles on foam cell formation were investigated. • Exposure to ZnO nanoparticles induced migration and adhesion of monocytes. • Exposure to ZnO nanoparticles increased macrophage cholesterol uptake. • Expression of membrane scavenger receptors of modified LDL was also increased. • These effects were not observed after exposure to TiO{sub 2} nanoparticles.

  16. Colloidal silver nanoparticles/rhamnolipid (SNPRL) composite as novel chemotactic antibacterial agent.

    Science.gov (United States)

    Bharali, P; Saikia, J P; Paul, S; Konwar, B K

    2013-10-01

    The antibacterial activity of silver nanoparticles and rhamnolipid are well known individually. In the present research, antibacterial and chemotactic activity due to colloidal silver nanoparticles (SNP), rhamnolipid (RL) and silver nanoparticles/rhamnolipid composite (SNPRL) were evaluated using Staphylococcus aureus (MTCC3160), Escherichia coli (MTCC40), Pseudomonas aeruginosa (MTCC8163) and Bacillus subtilis (MTCC441) as test strains. Further, the SNPRL nanoparticles were characterized using scanning electron microscopy (SEM), transmission electron microscopy (TEM) and Fourier transform infrared spectroscopy (FTIR). The observation clearly indicates that SNPRL shows prominent antibacterial and chemotactic activity in comparison to all of its individual precursor components.

  17. A synthetic peptide derived from human immunodeficiency virus type 1 gp120 downregulates the expression and function of chemokine receptors CCR5 and CXCR4 in monocytes by activating the 7-transmembrane G-protein-coupled receptor FPRL1/LXA4R.

    Science.gov (United States)

    Deng, X; Ueda, H; Su, S B; Gong, W; Dunlop, N M; Gao, J L; Murphy, P M; Wang, J M

    1999-08-15

    Because envelope gp120 of various strains of human immunodeficiency virus type 1 (HIV-1) downregulates the expression and function of a variety of chemoattractant receptors through a process of heterologous desensitization, we investigated whether epitopes derived from gp120 could mimic the effect. A synthetic peptide domain, designated F peptide, corresponding to amino acid residues 414-434 in the V4-C4 region of gp120 of the HIV-1 Bru strain, potently reduced monocyte binding and chemotaxis response to macrophage inflammatory protein 1beta (MIP-1beta) and stromal cell-derived factor 1alpha (SDF-1alpha), chemokines that use the receptors CCR5 and CXCR4, respectively. Further study showed that F peptide by itself is an inducer of chemotaxis and calcium mobilization in human monocytes and neutrophils. In cross-desensitization experiments, among the numerous chemoattractants tested, only the bacterial chemotactic peptide fMLF, when used at high concentrations, partially attenuated calcium mobilization induced by F peptide in phagocytes, suggesting that this peptide domain might share a 7-transmembrane, G-protein-coupled receptor with fMLF. By using cells transfected with cDNAs encoding receptors that interact with fMLF, we found that F peptide uses an fMLF receptor variant, FPRL1, as a functional receptor. The activation of monocytes by F peptide resulted in downregulation of the cell surface expression of CCR5 and CXCR4 in a protein kinase C-dependent manner. These results demonstrate that activation of FPRL1 on human moncytes by a peptide domain derived from HIV-1 gp120 could lead to desensitization of cell response to other chemoattractants. This may explain, at least in part, the initial activation of innate immune responses in HIV-1-infected patients followed by immune suppression.

  18. Crosstalk between medulloblastoma cells and endothelium triggers a strong chemotactic signal recruiting T lymphocytes to the tumor microenvironment.

    Directory of Open Access Journals (Sweden)

    Vita S Salsman

    Full Text Available Cancer cells can live and grow if they succeed in creating a favorable niche that often includes elements from the immune system. While T lymphocytes play an important role in the host response to tumor growth, the mechanism of their trafficking to the tumor remains poorly understood. We show here that T lymphocytes consistently infiltrate the primary brain cancer, medulloblastoma. We demonstrate, both in vitro and in vivo, that these T lymphocytes are attracted to tumor deposits only after the tumor cells have interacted with tumor vascular endothelium. Macrophage Migration Inhibitory Factor (MIF" is the key chemokine molecule secreted by tumor cells which induces the tumor vascular endothelial cells to secrete the potent T lymphocyte attractant "Regulated upon Activation, Normal T-cell Expressed, and Secreted (RANTES." This in turn creates a chemotactic gradient for RANTES-receptor bearing T lymphocytes. Manipulation of this pathway could have important therapeutic implications.

  19. Increasing the repeating units of ethylene glycol-based dimethacrylates directed toward reduced oxidative stress and co-stimulatory factors expression in human monocytic cells.

    Science.gov (United States)

    Tamura, Atsushi; Fukumoto, Izumi; Yui, Nobuhiko; Matsumura, Mitsuaki; Miura, Hiroyuki

    2015-03-01

    The ethylene glycol-based dimethacrylates are commonly used in biomaterials and dental restorative materials as a cross-linking agent. In this study, toxic effect of triethylene glycol dimethacrylate (TEGDMA) and poly(ethylene glycol) dimethacrylates (PEG-DMAs) with various ethylene glycol repeating units was investigated in terms of cytotoxicity, oxidative stress, and the expression of co-stimulatory factors in human leukemia cell line (THP-1 cells) to verify the effect of ethylene glycol repeating units. Note that the 1-octanol/water partition coefficient of PEG-based dimethacrylates decreased with increasing the ethylene glycol repeating units, indicating that the hydrophilicity of PEG-DMAs increased with ethylene glycol repeating units. The toxic effect of PEG-DMAs such as cytotoxicity, oxidative stress, and the expression of CD86 in treated THP-1 cells are reduced with increasing the ethylene glycol repeating units in PEG-DMAs. However, the expression of CD54 in treated THP-1 cells was not influenced with the ethylene glycol repeating units and the maximal expression level of CD54 was observed at the concentration range of 2-4 mM for all samples. Accordingly, hydrophilic character of PEG-DMAs with long ethylene glycol chains definitely alleviates the some toxic aspect of PEG-based DMAs. This finding would provide important insight into the design of new biomaterials and dental materials with superior biocompatibility. © 2014 Wiley Periodicals, Inc.

  20. Chemotactic signal transduction and phosphate metabolism as adaptive strategies during citrus canker induction by Xanthomonas citri.

    Science.gov (United States)

    Moreira, Leandro Marcio; Facincani, Agda Paula; Ferreira, Cristiano Barbalho; Ferreira, Rafael Marine; Ferro, Maria Inês Tiraboshi; Gozzo, Fabio Cesar; de Oliveira, Julio Cezar Franco; Ferro, Jesus Aparecido; Soares, Márcia Regina

    2015-03-01

    The genome of Xanthomonas citri subsp. Citri strain 306 pathotype A (Xac) was completely sequenced more than 10 years; to date, few studies involving functional genomics Xac and its host compatible have been developed, specially related to adaptive events that allow the survival of Xac within the plant. Proteomic analysis of Xac showed that the processes of chemotactic signal transduction and phosphate metabolism are key adaptive strategies during the interaction of a pathogenic bacterium with its plant host. The results also indicate the importance of a group of proteins that may not be directly related to the classical virulence factors, but that are likely fundamental to the success of the initial stages of the infection, such as methyl-accepting chemotaxis protein (Mcp) and phosphate specific transport (Pst). Furthermore, the analysis of the mutant of the gene pstB which codifies to an ABC phosphate transporter subunit revealed a complete absence of citrus canker symptoms when inoculated in compatible hosts. We also conducted an in silico analysis which established the possible network of genes regulated by two-component systems PhoPQ and PhoBR (related to phosphate metabolism), and possible transcriptional factor binding site (TFBS) motifs of regulatory proteins PhoB and PhoP, detaching high degree of conservation of PhoB TFBS in 84 genes of Xac genome. This is the first time that chemotaxis signal transduction and phosphate metabolism were therefore indicated to be fundamental to the process of colonization of plant tissue during the induction of disease associated with Xanthomonas genus bacteria.

  1. Inhibition of the differentiation of monocyte-derived dendritic cells by human gingival fibroblasts.

    Directory of Open Access Journals (Sweden)

    Sylvie Séguier

    Full Text Available We investigated whether gingival fibroblasts (GFs can modulate the differentiation and/or maturation of monocyte-derived dendritic cells (DCs and analyzed soluble factors that may be involved in this immune modulation. Experiments were performed using human monocytes in co-culture with human GFs in Transwell® chambers or using monocyte cultures treated with conditioned media (CM from GFs of four donors. The four CM and supernatants from cell culture were assayed by ELISA for cytokines involved in the differentiation of dendritic cells, such as IL-6, VEGF, TGFβ1, IL-13 and IL-10. The maturation of monocyte-derived DCs induced by LPS in presence of CM was also studied. Cell surface phenotype markers were analyzed by flow cytometry. In co-cultures, GFs inhibited the differentiation of monocyte-derived DCs and the strength of this blockade correlated with the GF/monocyte ratio. Conditioned media from GFs showed similar effects, suggesting the involvement of soluble factors produced by GFs. This inhibition was associated with a lower stimulatory activity in MLR of DCs generated with GFs or its CM. Neutralizing antibodies against IL-6 and VEGF significantly (P<0.05 inhibited the inhibitory effect of CM on the differentiation of monocytes-derived DCs and in a dose dependent manner. Our data suggest that IL-6 is the main factor responsible for the inhibition of DCs differentiation mediated by GFs but that VEGF is also involved and constitutes an additional mechanism.

  2. Chemotactic and mitogenic stimuli of neuronal apoptosis in patients with medically intractable temporal lobe epilepsy

    Science.gov (United States)

    Fiala, Milan; Avagyan, Hripsime; Merino, Jose Joaquin; Bernas, Michael; Valdivia, Juan; Espinosa-Jeffrey, Araceli; Witte, Marlys; Weinand, Martin

    2012-01-01

    To identify the upstream signals of neuronal apoptosis in patients with medically intractable temporal lobe epilepsy (TLE), we evaluated by immunohistochemistry and confocal microscopy brain tissues of 13 TLE patients and 5 control patients regarding expression of chemokines and cell-cycle proteins. The chemokine RANTES (CCR5) and other CC-chemokines and apoptotic markers (caspase-3, -8, -9) were expressed in lateral temporal cortical and hippocampal neurons of TLE patients, but not in neurons of control cases. The chemokine RANTES is usually found in cytoplasmic and extracellular locations. However, in TLE neurons, RANTES was displayed in an unusual location, the neuronal nuclei. In addition, the cell-cycle regulatory transcription factor E2F1 was found in an abnormal location in neuronal cytoplasm. The pro-inflammatory enzyme cyclooxygenase-2 and cytokine interleukin-1β were expressed both in neurons of patients suffering from temporal lobe epilepsy and from cerebral trauma. The vessels showed fibrin leakage, perivascular macrophages and expression of IL-6 on endothelial cells. In conclusion, the cytoplasmic effects of E2F1 and nuclear effects of RANTES might have novel roles in neuronal apoptosis of TLE neurons and indicate a need to develop new medical and/or surgical neuroprotective strategies against apoptotic signaling by these molecules. Both RANTES and E2F1 signaling are upstream from caspase activation, thus the antagonists of RANTES and/or E2F1 blockade might be neuroprotective for patients with medically intractable temporal lobe epilepsy. The results have implications for the development of new medical and surgical therapies based on inhibition of chemotactic and mitogenic stimuli of neuronal apoptosis in patients with medically intractable temporal lobe epilepsy. PMID:22444245

  3. Melanoma cells break down LPA to establish local gradients that drive chemotactic dispersal.

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    Andrew J Muinonen-Martin

    2014-10-01

    Full Text Available The high mortality of melanoma is caused by rapid spread of cancer cells, which occurs unusually early in tumour evolution. Unlike most solid tumours, thickness rather than cytological markers or differentiation is the best guide to metastatic potential. Multiple stimuli that drive melanoma cell migration have been described, but it is not clear which are responsible for invasion, nor if chemotactic gradients exist in real tumours. In a chamber-based assay for melanoma dispersal, we find that cells migrate efficiently away from one another, even in initially homogeneous medium. This dispersal is driven by positive chemotaxis rather than chemorepulsion or contact inhibition. The principal chemoattractant, unexpectedly active across all tumour stages, is the lipid agonist lysophosphatidic acid (LPA acting through the LPA receptor LPAR1. LPA induces chemotaxis of remarkable accuracy, and is both necessary and sufficient for chemotaxis and invasion in 2-D and 3-D assays. Growth factors, often described as tumour attractants, cause negligible chemotaxis themselves, but potentiate chemotaxis to LPA. Cells rapidly break down LPA present at substantial levels in culture medium and normal skin to generate outward-facing gradients. We measure LPA gradients across the margins of melanomas in vivo, confirming the physiological importance of our results. We conclude that LPA chemotaxis provides a strong drive for melanoma cells to invade outwards. Cells create their own gradients by acting as a sink, breaking down locally present LPA, and thus forming a gradient that is low in the tumour and high in the surrounding areas. The key step is not acquisition of sensitivity to the chemoattractant, but rather the tumour growing to break down enough LPA to form a gradient. Thus the stimulus that drives cell dispersal is not the presence of LPA itself, but the self-generated, outward-directed gradient.

  4. Enhanced Retention of Chemotactic Bacteria in a Pore Network with Residual NAPL Contamination

    Science.gov (United States)

    Ford, R.; Wang, X.

    2013-12-01

    Nonaqueous phase liquid (NAPL) contaminants are difficult to eliminate from natural aquifers due, in part, to the heterogeneous structure of the soil matrix. Residual NAPL ganglia remain trapped in regions where the hydraulic conductivity is relatively low. Bioremediation processes depend on adequate mixing of microbial populations and the groundwater contaminants that they degrade. The ability of bacteria to sense a chemical gradient and swim preferentially toward locations of higher concentration, known as chemotaxis, can enhance the mixing of bacteria with contaminant sources that may not be readily accessible by advection and dispersion alone. The impact of chemotaxis on bacterial abundance within a low conductivity NAPL-contaminated region of a well-characterized porous matrix was investigated. A microfluidic device was designed to mimic heterogeneous features of a contaminated groundwater system. NAPL ganglia (toluene) were trapped within a fine pore network, and bacteria were injected into the system through a highly conductive adjacent channel. Chemotactic bacteria (P. putida F1) migrated preferentially towards and accumulated in the vicinity of NAPL contaminant sources. The accumulation of chemotactic bacteria was 15% greater in comparison to a nonchemotactic mutant (P. putida F1 CheA). Bacteria in the microfluidic device were subjected to different flow velocities from 0.25 to 5 m/d encompassing the range of typical groundwater flow rates. Chemotactic bacteria exhibited greater accumulation near the intersection between the macrochannel and the porous network at a flow velocity of 0.5 m/d than both the nonchemotactic mutant control and the chemotactic bacteria at a higher flow velocity of 5 m/d. Breakthrough curves observed at the outlet provided indirect evidence that chemotactic bacteria were retained within the contaminated low permeable region for a longer time than the nonchemotactic bacteria at a flow velocity of 0.25 m/d. This retention was

  5. Monocyte-Derived Suppressor Cells in Transplantation.

    Science.gov (United States)

    Ochando, Jordi; Conde, Patricia; Bronte, Vincenzo

    Myeloid-derived suppressor cells (MDSC) are cells of myeloid origin with enhanced suppressive function. They are negative regulators of the immune responses and comprise a heterogeneous mixture of immunosuppressive cells of monocytic (M-MDSC) and granulocytic (G-MDSC) origin. A more recent nomenclature proposes the term "suppressive monocyte derived cells" (suppressive MCs) to define CSF1/CSF2-dependent mouse suppressor cells that develop from common monocyte progenitors (cMoPs) after birth. Here, we review the literature about monocytic-derived cells with demonstrated suppressor function in vitro and in vivo within the context of solid organ transplantation.

  6. The absolute lymphocyte/monocyte ratio recovery during ABVD treatment cycles is not significantly impacted by the use of myeloid growth factors and predicts clinical outcomes in classical Hodgkin lymphoma regardless of their use

    Directory of Open Access Journals (Sweden)

    Kaufman GP

    2014-07-01

    Full Text Available Gregory P Kaufman,1 Kay M Ristow,1,2 Svetomir N Markovic,1,2 Luis F Porrata1,2 1Department of Internal Medicine, 2Division of Hematology, Mayo Clinic, Rochester, MN, USA Abstract: Risk stratification of patients with classical Hodgkin lymphoma (cHL remains suboptimal. The ratio of the absolute lymphocyte count (ALC to absolute monocyte count (AMC both at diagnosis and during subsequent recovery from serial cycles of chemotherapy predicts survival in cHL, and possesses advantages over other commonly used prognostic markers. Myeloid growth factors (MGFs, while not strongly recommended for use in adriamycin, bleomycin, vinblastine, and dacarbazine (ABVD treatment cycles, are not uncommonly used to prevent the negative consequences of neutropenia. The effect that MGFs have on the ALC/AMC ratio during ABVD treatment cycles, if any, remains unclear. We retrospectively evaluated 208 patients with cHL, who were diagnosed, treated, and followed at Mayo Clinic Rochester between 1990 and 2014, and who had quantifiable records for the use of MGFs during ABVD treatment cycles. Having an ALC/AMC ratio <1.1 during all treatment cycles was confirmed as being a negative predictor of overall and progression free survival (hazard ratio [HR] 0.06, 95% confidence interval [CI] 0.03–0.14 and HR 0.08, 95% CI 0.04–0.17, respectively. Data on both the ALC/AMC ratio and use of MGFs were available for 1,979 half treatment cycles. When stratified to whether or not MGFs were given, the change in the ALC/AMC ratio as compared to the prior half cycle was found to be statistically insignificant (P=0.3445. No survival advantage was found with the administration of MGFs in any cycle of therapy (log rank P=0.5713. Our data validate the prognostic significance of having an ALC/AMC ratio of ≥1.1 regardless of the use of MGFs. Keywords: myeloid growth factors, classical Hodgkin lymphoma, survival ALC/AMC ratio, ABVD chemotherapy

  7. Chemotactic effect of urokinase-type plasminogen activator on mouse spermatozoa in vitro

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    The aim of this study is to investigate the chemotactic effect of urokinase-type plasminogen activator (uPA)on mouse spermatozoa.Capillary assays were applied to study the chemotactic activity of ascending and descending gradients of uPA.Firstly,the chemotactic effect of an ascending gradient of uPA on mouse spermatozoa was observed by counting the number of spermatozoa that migrated into the capillary after incubation with uPA for 5,10,20,and 30 min,respectively,compared with that after incubation with F10.Twenty minutes was a suitable incubation time to obtain a plateau of sperm accumulation.Meanwhile,to confirm the specific effect of uPA on mouse sperm chemotaxis,uPA inhibitor (PAI-1)and anti-uPAR rabbit IgG were added to the test solution containing 20 U/mL uPA,respectively.To exclude the possibility that PAI-1 and anti-uPAR rabbit IgG may affect sperm accumulation nonspecifically,PAIl and anti-uPAR rabbit IgG were added to F10,respectively.It was found that the chemotactic effect of uPA was neutralized completely by PAI-1 and anti-uPAR rabbit IgG.PAI-1 and anti-uPAR rabbit IgG had no neutralizing effect on the sperm chemotactic effect.Lastly,the sperm chemotaxis response to a descending gradient of uPA was also observed.Taken together,the results suggest that uPA can induce sperm chemotaxis in vitro by binding to its receptor on the sperm membrane and may act as a chemoattractant in precontacting sperm-egg communication thereby increasing the chance encounter of spermatozoa and eggs.

  8. Extracellular HIV Tat and Tat cysteine rich peptide increase CCR5 expression in monocytes

    Institute of Scientific and Technical Information of China (English)

    ZHENG Lin; YANG Yi-da; LU Guo-cai; SALVATO Maria S

    2005-01-01

    In our previous work we reported that HIV Tat and 6 cysteine rich peptides of Tat induce tumor necrosis factor-related apoptosis-induced ligand (TRAIL) in human monocytes (Yang et al., 2003). Here our results showed that HIV Tat and Tat cysteine rich peptide increase CCR5 expression in human monocytes, and this activity is inhibited by rabbit anti-Tat. Boiled Tat does not increase CCR5 expression in monocytes. These results provide insight into a new mechanism by which HIV Tat plays a key role in the pathogenesis of HIV-1 infection.

  9. Epstein-Barr virus induces MCP-1 secretion by human monocytes via TLR2.

    Science.gov (United States)

    Gaudreault, Eric; Fiola, Stéphanie; Olivier, Martin; Gosselin, Jean

    2007-08-01

    Epstein-Barr virus (EBV) is a gammaherpesvirus infecting the majority of the human adult population in the world. TLR2, a member of the Toll-like receptor (TLR) family, has been implicated in the immune responses to different viruses including members of the herpesvirus family, such as human cytomegalovirus, herpes simplex virus type 1, and varicella-zoster virus. In this report, we demonstrate that infectious and UV-inactivated EBV virions lead to the activation of NF-kappaB through TLR2 using HEK293 cells cotransfected with TLR2-expressing vector along with NF-kappaB-Luc reporter plasmid. NF-kappaB activation in HEK293-TLR2 cells (HEK293 cells transfected with TLR2) by EBV was not enhanced by the presence of CD14. The effect of EBV was abrogated by pretreating HEK293-TLR2 cells with blocking anti-TLR2 antibodies or by preincubating viral particles with neutralizing anti-EBV antibodies 72A1. In addition, EBV infection of primary human monocytes induced the release of MCP-1 (monocyte chemotactic protein 1), and the use of small interfering RNA targeting TLR2 significantly reduced such a chemokine response to EBV. Taken together, these results indicate that TLR2 may be an important pattern recognition receptor in the immune response directed against EBV infection.

  10. Short-term stimulation with interleukin (IL-4 enhances purified protein derivative-induced production of an eosinophil chemotactic lymphokine, but suppresses IL-5 production

    Directory of Open Access Journals (Sweden)

    Takehiko Nishiyama

    1998-01-01

    Full Text Available The effect of interleukin (IL-4 on eosinophil chemotactic lymphokine (ECL production from peripheral blood mononuclear cells (PBMC stimulated with purified protein derivative (PPD was examined. The PBMC stimulated with PPD in the absence of IL-4 failed to produce evident ECL. However, PPD-induced eosinophil chemotactic activity (ECA production was markedly enhanced in a dose-dependent manner by pretreatment of PBMC with IL-4. The most potent enhancement was induced by IL-4 at a concentration of 30 U in tuberculin-sensitive PBMC. Short-term pretreatment (30 min to 3 h was sufficient for the enhancement, whereas longer-term treatment was less effective. Eosinophil chemotactic lymphokine was found to be a CD4+ T cell-derived factor with an isoelectric point of approximately pH 7.0 and without heparin affinity, unlike chemokines such as RANTES and eotaxin. The effect of IL-4 on the production of other cytokines, such as interferon (IFN-γ, IL-5, RANTES (regulated on activation, normal T expressed and secreted, and granulocyte-macrophage colony stimulating factor (GM-CSF was also examined. Peripheral blood mononuclear cells produced all these cytokines when they were treated with PPD, even in the absence of IL-4. When PBMC were pretreated with IL-4, interestingly not only IFNy but also IL-5 production was suppressed by pretreatment with IL-4, although ECL production was enhanced by the pretreatment. In the case of RANTES and GM-CSF, significant amounts of these cytokines were produced, even without antigenic stimulation, and IL-4 pretreatment did not result in an enhancement of their production. It is thus suggested that IL-4, existing in allergic lesions, plays a crucial role in eosinophil accumulation mediated by the T cell-derived ECL.

  11. Monocytes from HIV+ individuals show impaired cholesterol efflux and increased foam cell formation after transendothelial migration

    Science.gov (United States)

    MAISA, Anna; HEARPS, Anna C.; ANGELOVICH, Thomas A.; PEREIRA, Candida F.; ZHOU, Jingling; SHI, Margaret D.Y.; PALMER, Clovis S.; MULLER, William A.; CROWE, Suzanne M.; JAWOROWSKI, Anthony

    2016-01-01

    Design HIV+ individuals have an increased risk of atherosclerosis and cardiovascular disease which is independent of antiretroviral therapy and traditional risk factors. Monocytes play a central role in the development of atherosclerosis, and HIV-related chronic inflammation and monocyte activation may contribute to increased atherosclerosis, but the mechanisms are unknown. Methods Using an in vitro model of atherosclerotic plaque formation, we measured the transendothelial migration of purified monocytes from age-matched HIV+ and uninfected donors and examined their differentiation into foam cells. Cholesterol efflux and the expression of cholesterol metabolism genes were also assessed. Results Monocytes from HIV+ individuals showed increased foam cell formation compared to controls (18.9% vs 0% respectively, p=0.004) and serum from virologically suppressed HIV+ individuals potentiated foam cell formation by monocytes from both uninfected and HIV+ donors. Plasma TNF levels were increased in HIV+ vs control donors (5.9 vs 3.5 pg/ml, p=0.02) and foam cell formation was inhibited by blocking antibodies to TNF receptors, suggesting a direct effect on monocyte differentiation to foam cells. Monocytes from virologically suppressed HIV+ donors showed impaired cholesterol efflux and decreased expression of key genes regulating cholesterol metabolism, including the cholesterol transporter ABCA1 (p=0.02). Conclusions Monocytes from HIV+ individuals show impaired cholesterol efflux and are primed for foam cell formation following trans-endothelial migration. Factors present in HIV+ serum, including elevated TNF levels, further enhance foam cell formation. The pro-atherogenic phenotype of monocytes persists in virologically suppressed HIV+ individuals and may contribute mechanistically to increased atherosclerosis in this population. PMID:26244384

  12. Distinct Renal Pathology and a Chemotactic Phenotype after Enterohemorrhagic Escherichia coli Shiga Toxins in Non-Human Primate Models of Hemolytic Uremic Syndrome

    Science.gov (United States)

    Stearns-Kurosawa, Deborah J.; Oh, Sun-Young; Cherla, Rama P.; Lee, Moo-Seung; Tesh, Vernon L.; Papin, James; Henderson, Joel; Kurosawa, Shinichiro

    2014-01-01

    Enterohemorrhagic Escherichia coli cause approximately 1.5 million infections globally with 176,000 cases occurring in the United States annually from ingesting contaminated food, most frequently E. coli O157:H7 in ground beef or fresh produce. In severe cases, the painful prodromal hemorrhagic colitis is complicated by potentially lethal hemolytic uremic syndrome (HUS), particularly in children. Bacterial Shiga-like toxins (Stx1, Stx2) are primarily responsible for HUS and the kidney and neurologic damage that ensue. Small animal models are hampered by the inability to reproduce HUS with thrombotic microangiopathy, hemolytic anemia, and acute kidney injury. Earlier, we showed that nonhuman primates (Papio) recapitulated clinical HUS after Stx challenge and that novel therapeutic intervention rescued the animals. Here, we present detailed light and electron microscopic pathology examination of the kidneys from these Stx studies. Stx1 challenge resulted in more severe glomerular endothelial injury, whereas the glomerular injury after Stx2 also included prominent mesangiolysis and an eosinophilic inflammatory infiltration. Both toxins induced glomerular platelet-rich thrombi, interstitial hemorrhage, and tubular injury. Analysis of kidney and other organs for inflammation biomarkers showed a striking chemotactic profile, with extremely high mRNA levels for IL-8, monocyte chemoattractant protein 1, and macrophage inflammatory protein 1α and elevated urine chemokines at 48 hours after challenge. These observations give unique insight into the pathologic consequences of each toxin in a near human setting and present potential pathways for therapeutic intervention. PMID:23402998

  13. Pharm GKB: Leukemia, Monocytic, Acute [PharmGKB

    Lifescience Database Archive (English)

    Full Text Available Overview Alternate Names: Synonym Acute Monoblastic Leukemia; Acute Monoblastic Leukemias; Acute... Monocytic Leukemia; Acute Monocytic Leukemias; Acute monoblastic leukaemia; Acute monoblastic leukemia; Acute... monocytic leukaemia; Acute monocytic leukemia, morphology; Acute monocytoid leukemia; Leukemia, Acute... Monoblastic; Leukemia, Acute Monocytic; Leukemia, Monoblastic, Acute; Leukemia, Myeloid, Acute... Schilling-Type Myeloid; Leukemias, Acute Monoblastic; Leukemias, Acute Monocytic; M5a - Acute monoblastic leukaemia; M5a - Acute

  14. Age Increases Monocyte Adhesion on Collagen

    Science.gov (United States)

    Khalaji, Samira; Zondler, Lisa; Kleinjan, Fenneke; Nolte, Ulla; Mulaw, Medhanie A.; Danzer, Karin M.; Weishaupt, Jochen H.; Gottschalk, Kay-E.

    2017-05-01

    Adhesion of monocytes to micro-injuries on arterial walls is an important early step in the occurrence and development of degenerative atherosclerotic lesions. At these injuries, collagen is exposed to the blood stream. We are interested whether age influences monocyte adhesion to collagen under flow, and hence influences the susceptibility to arteriosclerotic lesions. Therefore, we studied adhesion and rolling of human peripheral blood monocytes from old and young individuals on collagen type I coated surface under shear flow. We find that firm adhesion of monocytes to collagen type I is elevated in old individuals. Pre-stimulation by lipopolysaccharide increases the firm adhesion of monocytes homogeneously in older individuals, but heterogeneously in young individuals. Blocking integrin αx showed that adhesion of monocytes to collagen type I is specific to the main collagen binding integrin αxβ2. Surprisingly, we find no significant age-dependent difference in gene expression of integrin αx or integrin β2. However, if all integrins are activated from the outside, no differences exist between the age groups. Altered integrin activation therefore causes the increased adhesion. Our results show that the basal increase in integrin activation in monocytes from old individuals increases monocyte adhesion to collagen and therefore the risk for arteriosclerotic plaques.

  15. Age-dependent alterations of monocyte subsets and monocyte-related chemokine pathways in healthy adults

    Directory of Open Access Journals (Sweden)

    Trautwein Christian

    2010-06-01

    Full Text Available Abstract Background Recent experimental approaches have unraveled essential migratory and functional differences of monocyte subpopulations in mice. In order to possibly translate these findings into human physiology and pathophysiology, human monocyte subsets need to be carefully revisited in health and disease. In analogy to murine studies, we hypothesized that human monocyte subsets dynamically change during ageing, potentially influencing their functionality and contributing to immunosenescence. Results Circulating monocyte subsets, surface marker and chemokine receptor expression were analyzed in 181 healthy volunteers (median age 42, range 18-88. Unlike the unaffected total leukocyte or total monocyte counts, non-classical CD14+CD16+ monocytes significantly increased with age, but displayed reduced HLA-DR and CX3CR1 surface expression in the elderly. Classical CD14++CD16- monocyte counts did not vary dependent on age. Serum MCP-1 (CCL2, but not MIP1α (CCL3, MIP1β (CCL4 or fractalkine (CX3CL1 concentrations increased with age. Monocyte-derived macrophages from old or young individuals did not differ with respect to cytokine release in vitro at steady state or upon LPS stimulation. Conclusions Our study demonstrates dynamic changes of circulating monocytes during ageing in humans. The expansion of the non-classical CD14+CD16+ subtype, alterations of surface protein and chemokine receptor expression as well as circulating monocyte-related chemokines possibly contribute to the preserved functionality of the monocyte pool throughout adulthood.

  16. Intra-amniotic LPS modulation of TLR signaling in lung and blood monocytes of fetal sheep.

    Science.gov (United States)

    Kramer, Boris W; Kallapur, Suhas G; Moss, Timothy J; Nitsos, Ilias; Newnham, John P; Jobe, Alan H

    2009-04-01

    Epidemiological studies suggest that intra-uterine exposure to inflammation may prime postnatal immune responses. In fetal sheep, intra-amniotic injection of lipopolysaccharide (LPS) induced chorioamnionitis, lung inflammation and maturation, matured lung monocytes to macrophages and initiated systemic tolerance of fetal monocytes to subsequent challenge with LPS. We hypothesized that LPS-mediated chorioamnionitis altered the response of lung and blood monocytes to Toll-like receptor (TLR) ligands such as PamCysK4 (TLR2), flagellin (TLR5), and human CpG-DNA (TLR9). Time-mated ewes were given intra-amniotic injections of LPS or saline. Blood and lung monocytes were assessed after 2 days, 7 days and 2 days and 7 days repetitive LPS injections before delivery at 124 days gestational age (term 150 days). Responsiveness of blood and lung monocytes to TLR-ligands in vitro was assessed by interleukin (IL)-6, tumor necrosis factor-alpha (TNF-alpha) and hydrogen peroxide. Monocytes from preterm controls had minimal responses. Lipopolysaccharide-mediated chorioamnionitis increased IL-6, TNF- alpha and hydrogen peroxide to all TLR agonists in blood and lung monocytes. Repetitive exposure to antenatal LPS reduced IL-6, TNF- alpha and hydrogen peroxide to TLR-ligands suggesting tolerance. Tolerance to TLR-ligands reduced IL-1 receptor associated kinase-4 expression. Thus, repeated fetal exposure to LPS induced tolerance to other TLR-ligands. These modulations of fetal innate immunity have implications for host defense and injury responses in preterm infants.

  17. Evidence for unfolded protein response activation in monocytes from individuals with alpha-1 antitrypsin deficiency.

    LENUS (Irish Health Repository)

    Carroll, Tomás P

    2010-04-15

    The hereditary disorder alpha-1 antitrypsin (AAT) deficiency results from mutations in the SERPINA1 gene and presents with emphysema in young adults and liver disease in childhood. The most common form of AAT deficiency occurs because of the Z mutation, causing the protein to fold aberrantly and accumulate in the endoplasmic reticulum (ER). This leads to ER stress and contributes significantly to the liver disease associated with the condition. In addition to hepatocytes, AAT is also synthesized by monocytes, neutrophils, and epithelial cells. In this study we show for the first time that the unfolded protein response (UPR) is activated in quiescent monocytes from ZZ individuals. Activating transcription factor 4, X-box binding protein 1, and a subset of genes involved in the UPR are increased in monocytes from ZZ compared with MM individuals. This contributes to an inflammatory phenotype with ZZ monocytes exhibiting enhanced cytokine production and activation of the NF-kappaB pathway when compared with MM monocytes. In addition, we demonstrate intracellular accumulation of AAT within the ER of ZZ monocytes. These are the first data showing that Z AAT protein accumulation induces UPR activation in peripheral blood monocytes. These findings change the current paradigm regarding lung inflammation in AAT deficiency, which up until now was derived from the protease-anti-protease hypothesis, but which now must include the exaggerated inflammatory response generated by accumulated aberrantly folded AAT in circulating blood cells.

  18. Effect of zinc and nitric oxide on monocyte adhesion to endothelial cells under shear stress.

    Science.gov (United States)

    Lee, Sungmun; Eskin, Suzanne G; Shah, Ankit K; Schildmeyer, Lisa A; McIntire, Larry V

    2012-03-01

    This study describes the effect of zinc on monocyte adhesion to endothelial cells under different shear stress regimens, which may trigger atherogenesis. Human umbilical vein endothelial cells were exposed to steady shear stress (15 dynes/cm(2) or 1 dyne/cm(2)) or reversing shear stress (time average 1 dyne/cm(2)) for 24 h. In all shear stress regimes, zinc deficiency enhanced THP-1 cell adhesion, while heparinase III reduced monocyte adhesion following reversing shear stress exposure. Unlike other shear stress regimes, reversing shear stress alone enhanced monocyte adhesion, which may be associated with increased H(2)O(2) and superoxide together with relatively low levels of nitric oxide (NO) production. L-N(G)-Nitroarginine methyl ester (L-NAME) treatment increased monocyte adhesion under 15 dynes/cm(2) and under reversing shear stress. After reversing shear stress, monocyte adhesion dramatically increased with heparinase III treatment followed by a zinc scavenger. Static culture experiments supported the reduction of monocyte adhesion by zinc following endothelial cell cytokine activation. These results suggest that endothelial cell zinc levels are important for the inhibition of monocyte adhesion to endothelial cells, and may be one of the key factors in the early stages of atherogenesis.

  19. Monocytes loaded with indocyanine green as active homing contrast agents permit optical differentiation of infectious and non-infectious inflammation.

    Directory of Open Access Journals (Sweden)

    Joani M Christensen

    Full Text Available Distinguishing cutaneous infection from sterile inflammation is a diagnostic challenge and currently relies upon subjective interpretation of clinical parameters, microbiological data, and nonspecific imaging. Assessing characteristic variations in leukocytic infiltration may provide more specific information. In this study, we demonstrate that homing of systemically administered monocytes tagged using indocyanine green (ICG, an FDA-approved near infrared dye, may be assessed non-invasively using clinically-applicable laser angiography systems to investigate cutaneous inflammatory processes. RAW 264.7 mouse monocytes co-incubated with ICG fluoresce brightly in the near infrared range. In vitro, the loaded cells retained the ability to chemotax toward monocyte chemotactic protein-1. Following intravascular injection of loaded cells into BALB/c mice with induced sterile inflammation (Complete Freund's Adjuvant inoculation or infection (Group A Streptococcus inoculation of the hind limb, non-invasive whole animal imaging revealed local fluorescence at the inoculation site. There was significantly higher fluorescence of the inoculation site in the infection model than in the inflammation model as early as 2 hours after injection (p<0.05. Microscopic examination of bacterial inoculation site tissue revealed points of near infrared fluorescence, suggesting the presence of ICG-loaded cells. Development of a non-invasive technique to rapidly image inflammatory states without radiation may lead to new tools to distinguish infectious conditions from sterile inflammatory conditions at the bedside.

  20. Diminished monocytic HLA-DR expression and ex vivo cytokine secretion capacity in patients with glioblastoma: effect of tumor extirpation.

    Science.gov (United States)

    Woiciechowsky, C; Asadullah, K; Nestler, D; Schöning, B; Glöckner, F; Döcke, W D; Volk, H D

    1998-04-15

    Severe immunodysregulation on lymphocyte level has been described in patients with glioblastoma and is likely involved into its unfavorable prognosis. Although the major importance of monocytic cells for immunoregulation is well established, only very limited data exist regarding the monocyte status in glioblastoma patients. Here we demonstrate a markedly diminished monocytic HLA-DR expression and ex vivo cytokine secretion capacity (TNF-alpha, IL-1beta, IL-10) as signs for monocyte deactivation in glioblastoma patients but not in patients with astrocytoma. As known in immunocompromised patients from other reasons, monocyte deactivation indicate global immunodepression associated with an enhanced risk of infectious complications. Interestingly, tumor resection resulted in partial recovery from the monocytic deactivation. This suggests that the glioblastoma itself contributed to this phenomenon. However, IL-10 and the active forms of transforming growth factor-beta2 and -beta1, which are produced by glioblastoma cells and known to inhibit monocyte function, were not detectable in plasma in our patients. Moreover, low levels of the adrenocorticotropic hormone and cortisol excluded hypothalamo-pituitary-adrenal axis involvement. So, further investigations are necessary to clarify the mechanism. The demonstrated severe glioblastoma-associated monocytic deactivation may contribute to its unfavorable prognosis. Therefore, monocytes may represent target cells for new adjuvant immunotherapies in glioblastoma.

  1. Interleukin-6 production by human monocytes stimulated with Cryptococcus neoformans components.

    Science.gov (United States)

    Delfino, D; Cianci, L; Lupis, E; Celeste, A; Petrelli, M L; Curró, F; Cusumano, V; Teti, G

    1997-06-01

    In order to ascertain if Cryptococcus neoformans components can induce interleukin-6 (IL-6) production, we stimulated human whole blood with purified capsular products. Their potencies in stimulating IL-6 release were mannoproteins > galactoxylomannan = glucuronoxylomannan > alpha(1-3)glucan. IL-6 production was tumor necrosis factor alpha independent and required the presence of monocytes and plasma. Since IL-6 can stimulate replication of the human immunodeficiency virus in monocytic cells, these findings may be clinically relevant.

  2. Elevation of Platelet and Monocyte Activity Markers of Atherosclerosis in Haemodialysis Patients Compared to Peritoneal Dialysis Patients

    Directory of Open Access Journals (Sweden)

    Ksenija Stach

    2017-01-01

    Full Text Available Purpose. The predominant cause of mortality in dialysis patients are cardiovascular events. Platelet and monocyte activity markers play an important role in cardiovascular mortality and were assessed and related to dialysis quality criteria in haemodialysis (HD and peritoneal dialysis (PD patients. Methods. For this prospective comparative study, HD patients (n=41 and PD patients (n=10 were included. In whole blood samples, surface expression of CD62P and CD40L on platelets, tissue factor binding on monocytes, and platelet-monocyte aggregates were measured by flow cytometry. Plasma levels of MCP-1, IL-6, TNFα, and soluble CD40L were analysed by enzyme-linked immunosorbent assay. Results. Haemodialysis patients showed a significantly higher CD62P expression on platelets (p=0.017, significantly higher amount of platelet-monocyte aggregates (p<0.0001, and significantly more tissue factor binding on monocytes (p<0.0001 compared to PD patients. In PD patients, a significant correlation between Kt/V and platelet CD40L expression (r=0.867; 0.001 and between Kt/V and platelet CD62P expression (r=0.686; p=0.028 was observed, while there was no significant correlation between Kt/V and tissue factor binding on monocytes and platelet-monocyte aggregates, respectively. Conclusion. Platelet and monocyte activity markers are higher in HD patients in comparison with those in PD patients, possibly suggesting a higher risk of cardiovascular morbidity and mortality.

  3. Elevation of Platelet and Monocyte Activity Markers of Atherosclerosis in Haemodialysis Patients Compared to Peritoneal Dialysis Patients.

    Science.gov (United States)

    Stach, Ksenija; Karb, Susanne; Akin, Ibrahim; Borggrefe, Martin; Krämer, Bernhard; Kälsch, Thorsten; Kälsch, Anna-Isabelle

    2017-01-01

    The predominant cause of mortality in dialysis patients are cardiovascular events. Platelet and monocyte activity markers play an important role in cardiovascular mortality and were assessed and related to dialysis quality criteria in haemodialysis (HD) and peritoneal dialysis (PD) patients. For this prospective comparative study, HD patients (n = 41) and PD patients (n = 10) were included. In whole blood samples, surface expression of CD62P and CD40L on platelets, tissue factor binding on monocytes, and platelet-monocyte aggregates were measured by flow cytometry. Plasma levels of MCP-1, IL-6, TNFα, and soluble CD40L were analysed by enzyme-linked immunosorbent assay. Haemodialysis patients showed a significantly higher CD62P expression on platelets (p = 0.017), significantly higher amount of platelet-monocyte aggregates (p < 0.0001), and significantly more tissue factor binding on monocytes (p < 0.0001) compared to PD patients. In PD patients, a significant correlation between Kt/V and platelet CD40L expression (r = 0.867; 0.001) and between Kt/V and platelet CD62P expression (r = 0.686; p = 0.028) was observed, while there was no significant correlation between Kt/V and tissue factor binding on monocytes and platelet-monocyte aggregates, respectively. Platelet and monocyte activity markers are higher in HD patients in comparison with those in PD patients, possibly suggesting a higher risk of cardiovascular morbidity and mortality.

  4. Sesamin inhibits bacterial formylpeptide-induced inflammatory responses in a murine air-pouch model and in THP-1 human monocytes.

    Science.gov (United States)

    Cui, Youhong; Hou, Xinwei; Chen, Juan; Xie, Lianying; Yang, Lang; Le, Yingying

    2010-02-01

    The reaction of human leukocytes to chemoattractants is an important component of the host immune response and also plays a crucial role in the development of inflammation. Sesamin has been shown to inhibit lipid peroxidation and regulate cytokine production. In this study, we examined the effect of sesamin on inflammatory responses elicited by the bacterial chemotactic peptide N-formyl-methionyl-leucyl-phenylalanine (fMLF) in vitro and in vivo and explored the mechanisms involved. fMLF is recognized by a human G protein-coupled receptor formyl peptide receptor (FPR) on phagocytic leukocytes. Sesamin at concentrations between 12.5 and 50 micromol/L inhibited fMLF-induced chemotaxis of human monocyte cell line THP-1 differentiated with dibutyryl cyclic AMP (P sesamin inhibited FPR-transfected rat basophilic leukemia cell [epitope-tagged human FPR (ETFR) cell] migration toward fMLF (P sesamin (12 mgkg(-1)d(-1) for 2 d) suppressed leukocyte infiltration into the air pouch induced by fMLF [(62.89 +/- 7.93) x 10(4) vs. (19.67 +/- 4.43) x 10(4) cells/air pouch; n = 9; P sesamin inhibited fMLF-induced ERK1/2 phosphorylation in a dose-dependent manner but did not affect fMLF-induced Ca(2+) flux. Electrophoretic mobility shift assay showed that pretreatment of THP-1 cells with sesamin dose dependently inhibited fMLF-induced nuclear factor-kappaB (NF-kappaB) activation. These results suggest that sesamin inhibits leukocyte activation by fMLF through ERK1/2- and NF-kappaB-related signaling pathways and thus is a potential compound for the management of inflammatory diseases.

  5. Neutrophil chemotactic activity in bronchoalveolar lavage fluid of patients with AIDS-associated Pneumocystis carinii pneumonia

    DEFF Research Database (Denmark)

    Benfield, T L; Kharazmi, A; Larsen, C G

    1997-01-01

    Pneumocystis carinii pneumonia (PCP) is accompanied by an acute inflammatory infiltration of the lung parenchyma. The cellular infiltrate is characterized by inflammatory cells including neutrophils, lymphocytes and macrophages. Furthermore, neutrophilia in bronchoalveolar lavage (BAL) fluid has...... been shown to confer a poor prognosis in PCP. We therefore investigated the potential of BAL fluid from 17 patients with PCP to induce neutrophil chemotaxis. BAL fluid from patients induced considerable neutrophil chemotactic activity compared to normal controls. Elevated levels of IL-8 were detected...... in patient samples as compared to controls. A specific anti-IL-8 antibody significantly reduced chemotactic activity of patient samples by more than 50%. In conclusion, IL-8 appears to be a significant participant of neutrophil chemotaxis in AIDS-associated PCP, and may participate in the recruitment...

  6. Aberrant cGMP-binding activity in non-chemotactic Dictyostelium discoideum mutants

    NARCIS (Netherlands)

    Kuwayama, Hidekazu; Viel, Gerhard T.; Ishida, Shuji; Haastert, Peter J.M. van

    1995-01-01

    The kinetics of cGMP-binding to the major cGMP-binding activity in Dictyostelium, were investigated in 10 non-chemotactic mutants (KI mutants; KI-1 similar to 10). A wild-type cell contains about 3000 binding sites with a K-d of 1.5 nM. cGMP may dissociate from these binding sites with fast (F-type)

  7. Rapid chemotactic response enables marine bacteria to exploit ephemeral microscale nutrient patches

    OpenAIRE

    Stocker, Roman; Seymour, Justin R.; Samadani, Azadeh; Dana E Hunt; Polz, Martin F.

    2008-01-01

    Because ocean water is typically resource-poor, bacteria may gain significant growth advantages if they can exploit the ephemeral nutrient patches originating from numerous, small sources. Although this interaction has been proposed to enhance biogeochemical transformation rates in the ocean, it remains questionable whether bacteria are able to efficiently use patches before physical mechanisms dissipate them. Here we show that the rapid chemotactic response of the marine bacterium Pseudoalte...

  8. Chemotactic model for interaction of antagonistic microflora colonies and numerical simulations

    CERN Document Server

    Malaga, Carlos; Plaza, Ramon G; Simeoni, Chiara

    2011-01-01

    This paper studies a two-dimensional chemotactic model for two species in which one of them produces a chemo-repellent for the other. Under these circumstances, the chemical inhibits the invasion of a moving front for the second species. It is shown asymptotically and numerically how stable steady states, which depend on the chemical concentration, can be reached. The results qualitatively explain experimental observations by Swain and Ray, where colonies of bacteria produce metabolite agents which prevent the invasion of fungi.

  9. Monocyte subsets in myocardial infarction: A review.

    Science.gov (United States)

    Arfvidsson, John; Ahlin, Fredrik; Vargas, Kris G; Thaler, Barbara; Wojta, Johann; Huber, Kurt

    2017-03-15

    Monocytes form an important part of the human innate immune system by taking part in inflammatory reactions. With time, monocytes have gained interest in the role they may play during the event of myocardial infarction (MI). The current paradigm suggests that monocytes consist of three subdivisions which differ in phenotypic and dynamic patterns after an MI. In the inflammation that ensues, the different subsets have been shown to have an impact on reparative processes and patient recovery. We searched Medline and Embase until April 5, 2016, for observational studies or clinical trials regarding monocyte functions and dynamics in MI. Apart from studies in humans, extensive work has been done in mice in an effort to understand the complex nature of monocyte dynamics. Animal models might add useful information on mapping these processes. The question still remains whether animal data can, to a certain degree, be extrapolated to monocyte functions during human MI. This review aims to summarize current available evidence on both mice and men with particular focus on the understanding of monocyte subsets dynamics and effects in human MI. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  10. LEGO bricks used as chemotactic chambers: evaluation by a computer-assisted image analysis technique.

    Science.gov (United States)

    Azzarà, A; Chimenti, M

    2004-01-01

    One of the main techniques used to explore neutrophil motility, employs micropore filters in chemotactic chambers. Many new models have been proposed, in order to perform multiple microassays in a rapid, inexpensive and reproducible way. In this work, LEGO bricks have been used as chemotactic chambers in the evaluation of neutrophil random motility and chemotaxis and compared with conventional Boyden chambers in a "time-response" experiment. Neutrophil motility throughout the filters was evaluated by means of an image-processing workstation, in which a dedicated algorithm recognizes and counts the cells in several fields and focal planes throughout the whole filter; correlates counts and depth values; performs a statistical analysis of data; calculates the true value of neutrophil migration; determines the distribution of cells; and displays the migration pattern. By this method, we found that the distances travelled by the cells in conventional chambers and in LEGO bricks were perfectly identical, both in random migration and under chemotactic conditions. Moreover, no interference with the physiological behaviour of neutrophils was detectable. In fact, the kinetics of migration was identical both in random migration (characterized by a gaussian pattern) and in chemotaxis (characterized by a typical stimulation peak, previously identified by our workstation). In conclusion, LEGO bricks are extremely precise devices. They are simple to use and allow the use of small amounts of chemoattractant solution and cell suspension, supplying by itself a triplicate test. LEGO bricks are inexpensive, fast and suitable for current diagnostic activity or for research investigations in every laboratory.

  11. Cell-to-cell contact of human monocytes with infected arterial smooth-muscle cells enhances growth of Chlamydia pneumoniae.

    Science.gov (United States)

    Puolakkainen, Mirja; Campbell, Lee Ann; Lin, Tsun-Mei; Richards, Theresa; Patton, Dorothy L; Kuo, Cho-Chou

    2003-02-01

    Chlamydia pneumoniae can infect arterial cells. It has been shown that coculture of human monocytes (U937) and endothelial cells promotes infection of C. pneumoniae in endothelial cells and that the enhancement was mediated by a soluble factor (insulin-like growth factor 2) secreted by monocytes. In this study, it is shown that coculture of monocytes with C. pneumoniae enhances infection of C. pneumoniae in arterial smooth-muscle cells 5.3-fold at a monocyte-to-smooth-muscle cell ratio of 5. However, unlike endothelial cells, no enhancement was observed if monocytes were placed in cell culture inserts or if conditioned medium from monocyte cultures was used, which suggests that cell-to-cell contact is critical. The addition of mannose 6-phosphate or octyl glucoside, a nonionic detergent containing a sugar group, to cocultures inhibited the enhancement. These findings suggest that the monocyte-smooth-muscle cell interaction may be mediated by mannose 6-phosphate receptors present on monocytes.

  12. Molecular Mechanisms That Underlie the Dynamic Adaptation of Innate Monocyte Memory to Varying Stimulant Strength of TLR Ligands.

    Science.gov (United States)

    Yuan, Ruoxi; Geng, Shuo; Li, Liwu

    2016-01-01

    In adaptation to rising stimulant strength, innate monocytes can be dynamically programed to preferentially express either pro- or anti-inflammatory mediators. Such dynamic innate adaptation or programing may bear profound relevance in host health and disease. However, molecular mechanisms that govern innate adaptation to varying strength of stimulants are not well understood. Using lipopolysaccharide (LPS), the model stimulant of toll-like-receptor 4 (TLR4), we reported that the expressions of pro-inflammatory mediators are preferentially sustained in monocytes adapted by lower doses of LPS, and suppressed/tolerized in monocytes adapted by higher doses of LPS. Mechanistically, monocytes adapted by super-low dose LPS exhibited higher levels of transcription factor, interferon regulatory factor 5 (IRF5), and reduced levels of transcriptional modulator B lymphocyte-induced maturation protein-1 (Blimp-1). Intriguingly, the inflammatory monocyte adaptation by super-low dose LPS is dependent upon TRAM/TRIF but not MyD88. Similar to LPS, we also observed biphasic inflammatory adaptation and tolerance in monocytes challenged with varying dosages of TLR7 agonist. In sharp contrast, rising doses of TLR3 agonist preferentially caused inflammatory adaptation without inducing tolerance. At the molecular level, the differential regulation of IRF5 and Blimp-1 coincides with unique monocyte adaptation dynamics by TLR4/7 and TLR3 agonists. Our study provides novel clue toward the understanding of monocyte adaptation and memory toward distinct TLR ligands.

  13. Platelet activation attracts a subpopulation of effector monocytes to sites of Leishmania major infection.

    Science.gov (United States)

    Goncalves, Ricardo; Zhang, Xia; Cohen, Heather; Debrabant, Alain; Mosser, David M

    2011-06-01

    Leishmania species trigger a brisk inflammatory response and efficiently induce cell-mediated immunity. We examined the mechanisms whereby leukocytes were recruited into lesions after Leishmania major infection of mice. We found that a subpopulation of effector monocytes expressing the granulocyte marker GR1 (Ly6C) is rapidly recruited into lesions, and these monocytes efficiently kill L. major parasites. The recruitment of this subpopulation of monocytes depends on the chemokine receptor CCR2 and the activation of platelets. Activated platelets secrete platelet-derived growth factor, which induces the rapid release of CCL2 from leukocytes and mesenchymal cells. This work points to a new role for platelets in host defense involving the selective recruitment of a subpopulation of effector monocytes from the blood to efficiently kill this intracellular parasite.

  14. Tumour-derived microvesicles (TMV) mimic the effect of tumour cells on monocyte subpopulations.

    Science.gov (United States)

    Baj-Krzyworzeka, Monika; Baran, Jaroslaw; Weglarczyk, Kazimierz; Szatanek, Rafal; Szaflarska, Anna; Siedlar, Maciej; Zembala, Marek

    2010-09-01

    Monocytes/macrophages may be affected by tumour cells via cell-to-cell contact, soluble factors and by tumour-derived microvesicles (TMV). Previous observations indicate that TMV interact with monocytes and alter their immunophenotype and activity. This study was designed to determine interactions of TMV with subpopulations (CD14(++)CD16(-) and CD14(+)CD16(++)) of human monocytes. Engulfment of TMV by subsets of monocytes was analysed by flow cytometry. Moreover cytokine release and production of reactive oxygen intermediates (ROI) and reactive nitrogen intermediates (RNI) by CD14(++)CD16(-) and CD14(+)CD16(++) cells after TMV stimulation was determined. It was found that TMV are engulfed more efficiently by CD14(++)CD16(-) than CD14(+)CD16(++) cells. TMV-activated CD14(++)CD16(-) cells produce more ROI and interleukin -10 (IL-10) than CD14(++)CD16(+). CD14(+)CD16(++) cells following TMV stimulation showed an increased release of tumour necrosis factor alpha, IL-12p40 and RNI. TMV significantly modulate biological activity of monocyte subsets with a pattern similar to tumour cells. Therefore, TMV mimic the activating effect of tumour cells on monocytes as assessed by release of cytokines, ROI and RNI.

  15. Role of CC chemokines (macrophage inflammatory protein-1 beta, monocyte chemoattractant protein-1, RANTES) in acute lung injury in rats

    DEFF Research Database (Denmark)

    Bless, N M; Huber-Lang, M; Guo, R F

    2000-01-01

    were cloned, the proteins were expressed, and neutralizing Abs were developed. mRNA and protein expression for MIP-1 beta and MCP-1 were up-regulated during the inflammatory response, while mRNA and protein expression for RANTES were constitutive and unchanged during the inflammatory response...... that in chemokine-dependent inflammatory responses in lung CC chemokines do not necessarily demonstrate redundant function.......The role of the CC chemokines, macrophage inflammatory protein-1 beta (MIP-1 beta), monocyte chemotactic peptide-1 (MCP-1), and RANTES, in acute lung inflammatory injury induced by intrapulmonary deposition of IgG immune complexes injury in rats was determined. Rat MIP-1 beta, MCP-1, and RANTES...

  16. Generation of novel bone forming cells (monoosteophils from the cathelicidin-derived peptide LL-37 treated monocytes.

    Directory of Open Access Journals (Sweden)

    Zhifang Zhang

    Full Text Available BACKGROUND: Bone generation and maintenance involve osteoblasts, osteoclasts, and osteocytes which originate from unique precursors and rely on key growth factors for differentiation. However, an incomplete understanding of bone forming cells during wound healing has led to an unfilled clinical need such as nonunion of bone fractures. Since circulating monocytes are often recruited to sites of injury and may differentiate into various cell types including osteoclasts, we investigated the possibility that circulating monocytes in the context of tissue injury may also contribute to bone repair. In particular, we hypothesized that LL-37 (produced from hCAP-18, cathelicidin, which recruits circulating monocytes during injury, may play a role in bone repair. METHODS AND FINDINGS: Treatment of monocytes from blood with LL-37 for 6 days resulted in their differentiation to large adherent cells. Growth of LL-37-differentiated monocytes on osteologic discs reveals bone-like nodule formation by scanning electron microscopy (SEM. In vivo transplantation studies in NOD/SCID mice show that LL-37-differentiated monocytes form bone-like structures similar to endochondral bone formation. Importantly, LL-37-differentiated monocytes are distinct from conventional monocyte-derived osteoclasts, macrophages, and dendritic cells and do not express markers of the mesenchymal stem cells (MSC lineage, distinguishing them from the conventional precursors of osteoblasts. Furthermore, LL-37 differentiated monocytes express intracellular proteins of both the osteoblast and osteoclast lineage including osteocalcin (OC, osteonectin (ON, bone sialoprotein II (BSP II, osteopontin (OP, RANK, RANKL, MMP-9, tartrate resistant acid phosphatase (TRAP, and cathepsin K (CK. CONCLUSION: Blood derived monocytes treated with LL-37 can be differentiated into a novel bone forming cell that functions both in vitro and in vivo. We propose the name monoosteophil to indicate their monocyte

  17. Differential Constitutive and Cytokine-Modulated Expression of Human Toll-like Receptors in Primary Neutrophils, Monocytes, and Macrophages

    Directory of Open Access Journals (Sweden)

    D. Shane O'Mahony, Uyenvy Pham, Ramesh Iyer, Thomas R. Hawn, W. Conrad Liles

    2008-01-01

    Full Text Available Human Toll-like receptors (TLRs comprise a family of proteins that recognizes pathogen-associated molecular patterns (PAMPs and initiates host innate immune responses. Neutrophils, monocytes, and macrophages are critical cellular components of the human innate immune system. Proinflammatory cytokines, such as granulocyte colony-stimulating factor (G-CSF, granulocyte-macrophage colony-stimulating factor (GM-CSF, macrophage colony-stimulating factor (M-CSF, and interferon-γ (IFN-γ, have been shown to up-regulate microbicidal activity in these effector cells of innate immunity. Currently, the cellular and molecular mechanisms responsible for these effects are not completely understood. We hypothesized that these cytokines may up-regulate TLR expression as a mechanism to facilitate microbial recognition and augment the innate immune response. Using quantitative realtime rt-PCR technology, we examined constitutive expression of TLR2, TLR4, TLR5, and TLR9 mRNA and the effects of G-CSF, GM-CSF, M-CSF, and IFN-γ on TLR mRNA expression in purified populations of normal human neutrophils, monocytes, and monocyte-derived macrophages. Relative constitutive expression of TLR2, TLR4, and TLR9 was similar in neutrophils and monocytes. Constitutive expression of TLR5 was less in neutrophils compared to monocytes. Constitutive expression of TLR4 was greater and that of TLR9 lower in monocyte-derived macrophages compared to monocytes. Of the cytokines examined, IFN-γ and GM-CSF caused the greatest effects on TLR expression. IFN- γ up-regulated TLR2 and TLR4 in neutrophils and monocytes. GM-CSF up-regulated expression of TLR2 and TLR4 in neutrophils and TLR2 in monocytes. TLR5 was down-regulated by inflammatory cytokines in monocytes. These results suggest a potential role for IFN- γ and/or GM-CSF as therapeutic immunomodulators of the host defense to infection.

  18. Monocyte-Platelet Interaction Induces a Pro-Inflammatory Phenotype in Circulating Monocytes

    OpenAIRE

    2011-01-01

    BACKGROUND: Activated platelets exert a pro-inflammatory action that can be largely ascribed to their ability to interact with leukocytes and modulate their activity. We hypothesized that platelet activation and consequent formation of monocyte-platelet aggregates (MPA) induces a pro-inflammatory phenotype in circulating monocytes. METHODOLOGY/PRINCIPAL FINDINGS: CD62P(+) platelets and MPA were measured, and monocytes characterized, by whole blood flow cytometry in healthy subjects, before an...

  19. Monocyte scintigraphy in rheumatoid arthritis: the dynamics of monocyte migration in immune-mediated inflammatory disease.

    Directory of Open Access Journals (Sweden)

    Rogier M Thurlings

    Full Text Available BACKGROUND: Macrophages are principal drivers of synovial inflammation in rheumatoid arthritis (RA, a prototype immune-mediated inflammatory disease. Conceivably, synovial macrophages are continuously replaced by circulating monocytes in RA. Animal studies from the 1960s suggested that macrophage replacement by monocytes is a slow process in chronic inflammatory lesions. Translation of these data into the human condition has been hampered by the lack of available techniques to analyze monocyte migration in man. METHODS/PRINCIPAL FINDINGS: We developed a technique that enabled us to analyze the migration of labelled autologous monocytes in RA patients using single photon emission computer tomography (SPECT. We isolated CD14+ monocytes by CliniMACS in 8 patients and labeled these with technetium-99m (99mTc-HMPAO. Monocytes were re-infused into the same patient. Using SPECT we calculated that a very small but specific fraction of 3.4 x 10(-3 (0.95-5.1 x 10(-3 % of re-infused monocytes migrated to the inflamed joints, being detectable within one hour after re-infusion. CONCLUSIONS/SIGNIFICANCE: The results indicate monocytes migrate continuously into the inflamed synovial tissue of RA patients, but at a slow macrophage-replacement rate. This suggests that the rapid decrease in synovial macrophages that occurs after antirheumatic treatment might rather be explained by an alteration in macrophage retention than in monocyte influx and that RA might be particularly sensitive to treatments targeting inflammatory cell retention.

  20. Transforming growth factor-beta: possible roles in carcinogenesis.

    OpenAIRE

    Roberts, A B; Thompson, N L; Heine, U.; Flanders, C.; Sporn, M B

    1988-01-01

    TGF-beta is the prototype of a large family of multifunctional regulatory proteins. The principal sources of the peptide, platelets and bone, suggest that it plays a role in healing and remodeling processes. In vitro, TGF-beta is chemotactic for monocytes and fibroblasts and can greatly enhance accumulation of extracellular matrix components by fibroblasts. Its ability to stimulate the formation of granulation tissue locally and the demonstration of specific time- and tissue-dependent express...

  1. Interleukin-4 and 13 induce the expression and release of monocyte chemoattractant protein 1, interleukin-6 and stem cell factor from human detrusor smooth muscle cells: synergy with interleukin-1beta and tumor necrosis factor-alpha

    DEFF Research Database (Denmark)

    Bouchelouche, Kirsten; Andresen, Lars; Alvarez, Susana

    2006-01-01

    Interstitial cystitis is characterized by an increased number of activated MCs in the detrusor muscle. However, to our knowledge the factors that influence the anatomical relationship between MCs and HDSMCs are unknown. MCP-1, IL-6 and SCF have a critical role in the regulation of MC development,...

  2. Effect of bone marrow-derived monocytes transfected with RNA of mouse colon carcinoma on specific antitumor immunity

    Institute of Scientific and Technical Information of China (English)

    Xiao-Yuan Chu; Long-Bang Chen; Jing Zang; Jing-Hua Wang; Qun Zhang; Huai-Cheng Geng

    2005-01-01

    AIM: To investigate the effect of bone marrow-derived monocytes transfected with RNA of CT-26 (a cell line of mouse colon carcinoma) on antitumor immunity.METHODS: Mouse bone marrow-derived monocytes were incubated with mouse granulocyte macrophage colony stimulating factor (mGM-CSF) in vitro, and the purity of monocytes was detected by flow cytometry. Total RNA of CT-26 was obtained by TRIzol's process, and monocytes were transfected by TransMessenger in vitro. The activity of cytotoxic T lymphocytes (CTL)in vivo was estimated by the modified lactate dehydrogenase (LDH) release assay.Changes of tumor size in mice and animal's survival time were observed in different groups.RESULTS: Monocytes from mouse bone marrow were successfully incubated, and the positive rate of CD11b was over 95%. Vaccination of the monocytes transfected with total RNA induced a high level of specific CTL activity in vivo,and made mice resistant to the subsequent challenge of parental tumor cells. In vivo effects induced by monocytes transfected with total RNA were stronger than those incuced by monocytes pulsed with tumor cell lysates.CONCLUSION: Antigen presenting cells transfected with total RNA of CT-26 can present endogenous? tumor antigens, activate CTL, and effectively induce specific antitumor immunity.

  3. Monocytic HLA DR antigens in schizophrenic patients.

    Science.gov (United States)

    Krause, Daniela; Wagner, Jenny; Matz, Judith; Weidinger, Elif; Obermeier, Michael; Riedel, Michael; Gruber, Rudolf; Schwarz, Markus; Mueller, Norbert

    2012-01-01

    A genetic association of specific human leukocyte antigens (HLA) DR genes and schizophrenia has recently been shown. These HLA play a fundamental role in the control of immune responses. Furthermore infectious agents have been proposed to be involved in the pathogenesis of schizophrenia. In this study we investigated the rate of HLA DR positive monocytes in schizophrenic patients compared to controls with a special focus on the adaption to in vitro stimulation with toll-like receptor ligands. Patients with schizophrenia and matched controls were included. For each individual, we evaluated the rate of HLA DR positive monocytes (either incubated at 37 °C or after stimulation with lipopolysaccharide or Poly I:C). We found a significantly higher percentage of schizophrenic patients with elevated HLA DR positive cells (p=0.045) as compared to controls. The adjustment rate from baseline levels of monocytic HLA DR positive cells to stimulation with Poly I:C was significantly lower in schizophrenic patients (p=0.038). The increased monocytic HLA DR in schizophrenic patients and the maladjustment of their monocytic HLA DR levels to an infectious stimulus might be a sign for a disturbed monocytic immune balance in schizophrenic individuals.

  4. HIV-1 Latency in Monocytes/Macrophages

    Directory of Open Access Journals (Sweden)

    Amit Kumar

    2014-04-01

    Full Text Available Human immunodeficiency virus type 1 (HIV-1 targets CD4+ T cells and cells of the monocyte/macrophage lineage. HIV pathogenesis is characterized by the depletion of T lymphocytes and by the presence of a population of cells in which latency has been established called the HIV-1 reservoir. Highly active antiretroviral therapy (HAART has significantly improved the life of HIV-1 infected patients. However, complete eradication of HIV-1 from infected individuals is not possible without targeting latent sources of infection. HIV-1 establishes latent infection in resting CD4+ T cells and findings indicate that latency can also be established in the cells of monocyte/macrophage lineage. Monocyte/macrophage lineage includes among others, monocytes, macrophages and brain resident macrophages. These cells are relatively more resistant to apoptosis induced by HIV-1, thus are important stable hideouts of the virus. Much effort has been made in the direction of eliminating HIV-1 resting CD4+ T-cell reservoirs. However, it is impossible to achieve a cure for HIV-1 without considering these neglected latent reservoirs, the cells of monocyte/macrophage lineage. In this review we will describe our current understanding of the mechanism of latency in monocyte/macrophage lineage and how such cells can be specifically eliminated from the infected host.

  5. Nucleosome loss facilitates the chemotactic response of macrophages.

    Science.gov (United States)

    De Toma, I; Rossetti, G; Zambrano, S; Bianchi, M E; Agresti, A

    2014-11-01

    High mobility group box 1 (HMGB1) is a small nuclear protein with two functions. In the nucleus, it helps to wrap DNA around nucleosomes. When secreted, it recruits inflammatory cells and induces cytokine production. Before HMGB1 is secreted from inflammatory cells, it relocates to the cytoplasm, which partially or totally depletes cell nuclei of HMGB1. We previously showed that cells lacking HMGB1 contain 20% fewer nucleosomes and 30% more RNA transcripts levels genome-wide. We hypothesized that the depletion of nuclear HMGB1 plays a role in inflammation that can enhance or complement the role of extracellular HMGB1. We analysed the transcriptional profile of wild-type and Hmgb1-/- mouse embryonic fibroblasts (MEFs) as a proxy for cells that have lost HMGB1 from their nuclei. We explored the transcriptome of wild-type and Hmgb1-/- macrophages differentiated in the presence of granulocyte-macrophage colony-stimulating factor, before and after exposure to LPS/IFN-γ. In the same cells, histones and nuclear HMGB1 were quantified. We found that Hmgb1-/- MEFs show a transcriptional profile associated with stress and inflammation responses. Moreover, wild-type macrophages that have secreted HMGB1 because of LPS/IFN-γ exposure rapidly reduce their histone content as much as cells that genetically lack HMGB1. Importantly, unstimulated Hmgb1-/- macrophages activate transcriptional pathways associated with cell migration and chemotaxis. We suggest that nucleosome loss is an early event that facilitates transcriptional responses of macrophages to inflammation, particularly chemotaxis. HMGB1's dual roles in the nucleus and in the extracellular space appear to be complementary. © 2014 The Association for the Publication of the Journal of Internal Medicine.

  6. Heparin-like polymers modulate proinflammatory cytokine production by lipopolysaccharide-stimulated human monocytes.

    Science.gov (United States)

    Anastase-Ravion, Sylvie; Carreno, Marie-Paule; Blondin, Catherine; Ravion, Olivier; Champion, Jacqueline; Chaubet, Frédéric; Haeffner-Cavaillon, Nicole; Letourneur, Didier

    2002-06-05

    The search for heparin-like materials remains an intensive field of research. In this context, we studied the immunomodulatory properties of semisynthetic dextran derivatives and naturally occurring sulfated polysaccharides present in brown seaweed (fucans). In this study, we investigated the functional potencies of fucan and dextran derivatives by analyzing their effects on the release of proinflammatory cytokines by resting or lipopolysaccharide (LPS)-stimulated human monocytes and their interactions on monocyte surfaces. The results showed that fucan, dextran derivatives, and heparin differentially (1) triggered interleukin-1alpha, tumor necrosis factor alpha, interleukin-6, and interleukin-8 production by monocytes in a dose-dependent manner, (2) modulated cytokine production by LPS-stimulated monocytes, and (3) specifically inhibited the binding of biotinylated LPS to monocyte membranes. Taken together, these data indicated that fucan and dextran derivatives displayed interesting immunomodulatory effects on human blood cells that could be relevant as new drugs or biomaterial coatings. Indeed, such polysaccharides, by regulating monocyte activation, could contribute to the improved biocompatibility of implants.

  7. Monocyte matrix metalloproteinase production in Type 2 diabetes and controls – a cross sectional study

    Directory of Open Access Journals (Sweden)

    Davies Isabel R

    2003-03-01

    Full Text Available Abstract Background Coronary plaque rupture may result from localised over expression of matrix metalloproteinases (MMPs within the plaque by infiltrating monocyte – macrophages. As MMP expression can be promoted by the modified lipoproteins, oxidative stress and hyperglycaemia that characterises Type 2 diabetes, we hypothesised that peripheral monocytes in these patients, exposed to these factors in vivo, would demonstrate increased MMP production compared to controls. Methods We examined peripheral venous monocyte expression of MMP and tissue inhibitor of metalloproteinase-1 (TIMP-1 in 18 controls and 22 subjects with Type 2 diabetes and no previous cardiovascular complications. Results No significant difference in MMP-1, 3 or 9 or TIMP-1 production was observed between control and diabetes groups. Conclusions Monocyte MMP-1, 3, and 9, and TIMP-1, production are not abnormal in Type 2 diabetes. This data cannot be extrapolated to monocyte – macrophage behaviour in the vessel wall, but it does suggest MMP and TIMP-1 expression prior to monocyte infiltration and transformation are not abnormal in Type 2 diabetes.

  8. β2-Agonist clenbuterol hinders human monocyte differentiation into dendritic cells.

    Science.gov (United States)

    Giordani, Luciana; Cuzziol, Noemi; Del Pinto, Tamara; Sanchez, Massimo; Maccari, Sonia; Massimi, Alessia; Pietraforte, Donatella; Viora, Marina

    2015-12-10

    Clenbuterol (CLB) is a beta2-adrenergic agonist commonly used in asthma therapy, but is also a non-steroidal anabolic drug often abused in sport doping practices. Here we evaluated the in vitro impact of CLB on the physiology and function of human monocytes and dendritic cells (DCs), instrumental in the development of immune responses. We demonstrate that CLB inhibits the differentiation of monocytes into DCs and this effect is specific and dependent on β2-adrenergic receptor (AR) activation. We found that CLB treatment reduced the percentage of CD1a(+) immature DCs, while increasing the frequency of monocytes retaining CD14 surface expression. Moreover, CLB inhibited tumor necrosis factor-alpha (TNF-alpha) enhanced IL-(interleukin)-10 and IL-6 production. In contrast, CLB did not modulate the phenotypic and functional properties of monocytes and DCs, such as the surface expression of HLA-DR, CD83, CD80 and CD86 molecules, cytokine production, immunostimulatory activity and phagocytic activity. Moreover, we found that CLB did not modulate the activation of NF-kB in DCs. Moreover, we found that the differentiation of monocytes into DCs was associated with a significant decrease of β2-ARs mRNA expression. These results provide new insights on the effect of CLB on monocyte differentiation into DCs. Considering the frequent illegal use of CLB in doping, our work suggests that this drug is potentially harmful to immune responses decreasing the supply of DCs, thus subverting immune surveillance.

  9. CCN1/CYR61-mediated meticulous patrolling by Ly6Clow monocytes fuels vascular inflammation.

    Science.gov (United States)

    Imhof, Beat A; Jemelin, Stephane; Ballet, Romain; Vesin, Christian; Schapira, Marco; Karaca, Melis; Emre, Yalin

    2016-08-16

    Inflammation is characterized by the recruitment of leukocytes from the bloodstream. The rapid arrival of neutrophils is followed by a wave of inflammatory lymphocyte antigen 6 complex (Ly6C)-positive monocytes. In contrast Ly6C(low) monocytes survey the endothelium in the steady state, but their role in inflammation is still unclear. Here, using confocal intravital microscopy, we show that upon Toll-like receptor 7/8 (TLR7/8)-mediated inflammation of mesenteric veins, platelet activation drives the rapid mobilization of Ly6C(low) monocytes to the luminal side of the endothelium. After repeatedly interacting with platelets, Ly6C(low) monocytes commit to a meticulous patrolling of the endothelial wall and orchestrate the subsequent arrival and extravasation of neutrophils through the production of proinflammatory cytokines and chemokines. At a molecular level, we show that cysteine-rich protein 61 (CYR61)/CYR61 connective tissue growth factor nephroblastoma overexpressed 1 (CCN1) protein is released by activated platelets and enables the recruitment of Ly6C(low) monocytes upon vascular inflammation. In addition endothelium-bound CCN1 sustains the adequate patrolling of Ly6C(low) monocytes both in the steady state and under inflammatory conditions. Blocking CCN1 or platelets with specific antibodies impaired the early arrival of Ly6C(low) monocytes and abolished the recruitment of neutrophils. These results refine the leukocyte recruitment cascade model by introducing endothelium-bound CCN1 as an inflammation mediator and by demonstrating a role for platelets and patrolling Ly6C(low) monocytes in acute vascular inflammation.

  10. Monocyte differentiation in localized juvenile periodontitis is skewed toward the dendritic cell phenotype.

    Science.gov (United States)

    Barbour, Suzanne E; Ishihara, Yuichi; Fakher, Mohammed; Al-Darmaki, Salma; Caven, Timothy H; Shelburne, C P; Best, Al M; Schenkein, Harvey A; Tew, John G

    2002-06-01

    Several lines of evidence indicate that the monocytes of subjects with localized juvenile periodontitis (LJP) are functionally distinct from cells of age- and race-matched nonperiodontitis (NP) subjects. Among the abnormalities are the propensity to secrete large amounts of prostaglandin E(2) and the induction of immunoglobulin G2 (IgG2) antibodies. The experiments described here were performed to further characterize the LJP monocytes and to determine if these cells mature differently than NP monocytes. When adherent monocytes from LJP subjects were cultured in the presence of human serum, both macrophages and cells with the morphology of immature monocyte-derived dendritic cells (MDDC) were observed. Within 4 days the prevalence of the immature MDDC was approximately twofold higher in LJP cultures than in NP cultures. In addition to their dendritic morphology, these cells were CD11c(+) and CD14(-) or CD14(low) and stimulated potent autologous mixed leukocyte reactions, consistent with differentiation to the MDDC phenotype. Like LJP monocytes, cultures of MDDC generated with interleukin-4 and granulocyte-macrophage colony-stimulating factor selectively induced IgG2 in cultures of pokeweed mitogen-stimulated NP leukocytes. Together, these data suggest that the monocytes of LJP subjects have a propensity to differentiate into MDDC and that this differentiation may be related to the high levels of IgG2 that are observed in the sera of LJP subjects. As high levels of circulating IgG2 are correlated with less severe disease, the propensity of LJP monocytes to differentiate into MDDC may have important implications for both the host response against oral pathogens and the progression of LJP.

  11. Phospholipase D from Loxosceles laeta Spider Venom Induces IL-6, IL-8, CXCL1/GRO-α, and CCL2/MCP-1 Production in Human Skin Fibroblasts and Stimulates Monocytes Migration

    Directory of Open Access Journals (Sweden)

    José M. Rojas

    2017-04-01

    Full Text Available Cutaneous loxoscelism envenomation by Loxosceles spiders is characterized by the development of a dermonecrotic lesion, strong inflammatory response, the production of pro-inflammatory mediators, and leukocyte migration to the bite site. The role of phospholipase D (PLD from Loxosceles in the recruitment and migration of monocytes to the envenomation site has not yet been described. This study reports on the expression and production profiles of cytokines and chemokines in human skin fibroblasts treated with catalytically active and inactive recombinant PLDs from Loxosceles laeta (rLlPLD and lipid inflammatory mediators ceramide 1-phosphate (C1P and lysophosphatidic acid (LPA, and the evaluation of their roles in monocyte migration. Recombinant rLlPLD1 (active and rLlPLD2 (inactive isoforms induce interleukin (IL-6, IL-8, CXCL1/GRO-α, and CCL2/monocyte chemoattractant protein-1 (MCP-1 expression and secretion in fibroblasts. Meanwhile, C1P and LPA only exhibited a minor effect on the expression and secretion of these cytokines and chemokines. Moreover, neutralization of both enzymes with anti-rLlPLD1 antibodies completely inhibited the secretion of these cytokines and chemokines. Importantly, conditioned media from fibroblasts, treated with rLlPLDs, stimulated the transmigration of THP-1 monocytes. Our data demonstrate the direct role of PLDs in chemotactic mediator synthesis for monocytes in human skin fibroblasts and indicate that inflammatory processes play an important role during loxoscelism.

  12. Transcellular lipoxygenase metabolism between monocytes and platelets

    Energy Technology Data Exchange (ETDEWEB)

    Bigby, T.D.; Meslier, N. (Univ. of California, San Francisco (USA))

    1989-09-15

    We have examined the effects of co-culture and in vitro co-stimulation on lipoxygenase metabolism in monocytes and platelets. Monocytes were obtained from the peripheral blood of normal volunteers by discontinuous gradient centrifugation and adherence to tissue culture plastic. Platelets were obtained from the platelet-rich plasma of the same donor. When 10(9) platelets and 2.5 x 10(6) monocytes were co-stimulated with 1 microM A23187, these preparations released greater quantities of 12(S)-hydroxy-10-trans-5,8,14-cis-eicosatetraenoic acid, 5(S),12-(S)dihydroxy-6,10-trans-8,14-cis-eicosatetraenoic acid, and leukotriene C4, 5(S)-hydroxy-6(R)-S-glutathionyl-7,9-trans-11,14-cis-eicosatetraenoic (LTC4) when compared with monocytes alone. Release of arachidonic acid, 5-HETE, delta 6-trans-LTB4, and delta 6-trans-12-epi-LTB4 from monocytes was decreased in the presence of platelets. A dose-response curve was constructed and revealed that the above changes became evident when the platelet number exceeded 10(7). Dual radiolabeling experiments with 3H- and 14C-arachidonic acid revealed that monocytes provided arachidonic acid, 5-HETE, and LTA4 for further metabolism by the platelet. Monocytes did not metabolize platelet intermediates detectably. In addition, as much as 1.2 microM 12(S)-hydroxy-10-trans-5,8,14-cis-eicosatetraenoic acid and 12(S)-hydroperoxy-10-trans-5,8,14-cis-eicosatetraenoic acid had no effect on monocyte lipoxygenase metabolism. Platelets were capable of converting LTA4 to LTC4, but conversion of LTA4 to LTB4 was not detected. We conclude that the monocyte and platelet lipoxygenase pathways undergo a transcellular lipoxygenase interaction that differs from the interaction of the neutrophil and platelet lipoxygenase pathways. In this interaction monocytes provide intermediate substrates for further metabolic conversion by platelets in an unidirectional manner.

  13. Transduced monocyte/macrophages targeted to murine skin by UV light.

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    Zhang, Alexandra Y; Wu, Caiyun; Zhou, Lixin; Ismail, Sahar A; Tao, Jianming; McCormick, Laura L; Cooper, Kevin D; Gilliam, Anita C

    2006-01-01

    We have selectively targeted monocyte/macrophages overexpressing an immunomodulatory molecule, latency-associated peptide (LAP), a naturally occurring antagonist for transforming growth factor-beta1, to murine skin utilizing UV light to produce a cutaneous influx of transduced monocyte/macrophages. Bone marrow (BM) cells from BALB/c mice were transduced in vitro with a retroviral construct containing green fluorescent protein (GFP) for detection and human LAP (hLAP) as a test molecule. The transduced BM cells were then cultured in vitro with granulocyte-macrophage colony-stimulating factor (GM-CSF) to produce differentiation to monocyte/macrophages. More than 80% of transduced BM cells were CD11b-positive and MOMA-positive by fluorescence-activated cell-sorter analysis and secreted LAP by ELISA after 10 days of culture in granulocyte-macrophage colony-stimulating factor (GM-CSF). Transduced monocyte/macrophages containing either GFP or hLAP-GFP were then injected intravenously into BALB/c mice. One-half of recipients in each group were exposed to UVB (72 mJ) to induce monocyte/macrophage infiltration into skin. Recipients were sacrificed 60 h after UV irradiation. We found transduced cutaneous macrophages expressing GFP by examining with fluorescence microscopy frozen skin sections of recipient mice immunostained with antibodies to GFP and to macrophage marker F4/80. We identified hLAP sequences by polymerase chain reaction (PCR) of total DNA in recipient blood and UV-irradiated skin but not in unirradiated skin. LAP sequences were also detected at much lower levels in other organs (lung, spleen, and liver) by PCR. Therefore, we have shown that genetically altered monocytic cells can be injected intravenously and targeted to mouse skin by UV exposure. This macrophage-based gene-transfer method may be a potentially useful immunotherapeutic approach for delivering monocyte/macrophage-derived products to skin.

  14. Cadmium Exposure Is Associated with Monocyte Count and Monocyte to HDL Ratio, a Marker of Inflammation and Future Cardiovascular Disease in the Male Population.

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    Baek, Kiook; Chung, Insung

    2017-09-01

    Cadmium is a heavy metal that humans can be exposed to the in environment and occupation, and its relationship with cardiovascular diseases has been reported. in various reports. Epidemiological studies have also been associated with various inflammatory markers of cardiovascular diseases. In this study, we examined the relationship between monocyte count and monocyte to high density lipoprotein (HDL) ratio (MHR) and blood cadmium, which are one of the inflammatory markers of cardiovascular diseases. Data from a total of 733 male fire officers who received a health checkup at a hospital for one year in 2016 were analyzed. Populations were classified into 4 groups according to the quartile of blood cadmium and general characteristics were described. The relationship between monocyte count, MHR and cadmium in blood was statistically analyzed by linear regression analysis. In the univariate analysis and multivariate analysis, monocyte count was significantly higher in the second, third and fourth quartile groups than in the first quartile of cadmium, and the linear trend was significant. In univariate and multivariate analysis, MHR was significantly higher in the third and fourth quartile groups than in the first quartile group, and the linear trend was also significant. This study showed the significant relationship between blood cadmium and monocyte count and MHR among male fire officers. This was also statistically significant in the model adjusted for possible confounders and other cardiovascular risk factors and showed a linear trend. © 2017 The Korean Academy of Medical Sciences.

  15. Chemotactic Motility of Pseudomonas fluorescens F113 under Aerobic and Denitrification Conditions.

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    Candela Muriel

    Full Text Available The sequence of the genome of Pseudomonas fluorescens F113 has shown the presence of multiple traits relevant for rhizosphere colonization and plant growth promotion. Among these traits are denitrification and chemotactic motility. Besides aerobic growth, F113 is able to grow anaerobically using nitrate and nitrite as final electron acceptors. F113 is able to perform swimming motility under aerobic conditions and under anaerobic conditions when nitrate is used as the electron acceptor. However, nitrite can not support swimming motility. Regulation of swimming motility is similar under aerobic and anaerobic conditions, since mutants that are hypermotile under aerobic conditions, such as gacS, sadB, kinB, algU and wspR, are also hypermotile under anaerobic conditions. However, chemotactic behavior is different under aerobic and denitrification conditions. Unlike most pseudomonads, the F113 genome encode three complete chemotaxis systems, Che1, Che2 and Che3. Mutations in each of the cheA genes of the three Che systems has shown that the three systems are functional and independent. Mutation of the cheA1 gene completely abolished swimming motility both under aerobic and denitrification conditions. Mutation of the cheA2 gene, showed only a decrease in swimming motility under both conditions, indicating that this system is not essential for chemotactic motility but is necessary for optimal motility. Mutation of the cheA3 gene abolished motility under denitrification conditions but only produced a decrease in motility under aerobic conditions. The three Che systems proved to be implicated in competitive rhizosphere colonization, being the cheA1 mutant the most affected.

  16. Identification of a chemoreceptor for tricarboxylic acid cycle intermediates: differential chemotactic response towards receptor ligands.

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    Lacal, Jesús; Alfonso, Carlos; Liu, Xianxian; Parales, Rebecca E; Morel, Bertrand; Conejero-Lara, Francisco; Rivas, Germán; Duque, Estrella; Ramos, Juan L; Krell, Tino

    2010-07-23

    We report the identification of McpS as the specific chemoreceptor for 6 tricarboxylic acid (TCA) cycle intermediates and butyrate in Pseudomonas putida. The analysis of the bacterial mutant deficient in mcpS and complementation assays demonstrate that McpS is the only chemoreceptor of TCA cycle intermediates in the strain under study. TCA cycle intermediates are abundantly present in root exudates, and taxis toward these compounds is proposed to facilitate the access to carbon sources. McpS has an unusually large ligand-binding domain (LBD) that is un-annotated in InterPro and is predicted to contain 6 helices. The ligand profile of McpS was determined by isothermal titration calorimetry of purified recombinant LBD (McpS-LBD). McpS recognizes TCA cycle intermediates but does not bind very close structural homologues and derivatives like maleate, aspartate, or tricarballylate. This implies that functional similarity of ligands, such as being part of the same pathway, and not structural similarity is the primary element, which has driven the evolution of receptor specificity. The magnitude of chemotactic responses toward these 7 chemoattractants, as determined by qualitative and quantitative chemotaxis assays, differed largely. Ligands that cause a strong chemotactic response (malate, succinate, and fumarate) were found by differential scanning calorimetry to increase significantly the midpoint of protein unfolding (T(m)) and unfolding enthalpy (DeltaH) of McpS-LBD. Equilibrium sedimentation studies show that malate, the chemoattractant that causes the strongest chemotactic response, stabilizes the dimeric state of McpS-LBD. In this respect clear parallels exist to the Tar receptor and other eukaryotic receptors, which are discussed.

  17. Human type II pneumocyte chemotactic responses to CXCR3 activation are mediated by splice variant A.

    Science.gov (United States)

    Ji, Rong; Lee, Clement M; Gonzales, Linda W; Yang, Yi; Aksoy, Mark O; Wang, Ping; Brailoiu, Eugen; Dun, Nae; Hurford, Matthew T; Kelsen, Steven G

    2008-06-01

    Chemokine receptors control several fundamental cellular processes in both hematopoietic and structural cells, including directed cell movement, i.e., chemotaxis, cell differentiation, and proliferation. We have previously demonstrated that CXCR3, the chemokine receptor expressed by Th1/Tc1 inflammatory cells present in the lung, is also expressed by human airway epithelial cells. In airway epithelial cells, activation of CXCR3 induces airway epithelial cell movement and proliferation, processes that underlie lung repair. The present study examined the expression and function of CXCR3 in human alveolar type II pneumocytes, whose destruction causes emphysema. CXCR3 was present in human fetal and adult type II pneumocytes as assessed by immunocytochemistry, immunohistochemistry, and Western blotting. CXCR3-A and -B splice variant mRNA was present constitutively in cultured type II cells, but levels of CXCR3-B greatly exceeded CXCR3-A mRNA. In cultured type II cells, I-TAC, IP-10, and Mig induced chemotaxis. Overexpression of CXCR3-A in the A549 pneumocyte cell line produced robust chemotactic responses to I-TAC and IP-10. In contrast, I-TAC did not induce chemotactic responses in CXCR3-B and mock-transfected cells. Finally, I-TAC increased cytosolic Ca(2+) and activated the extracellular signal-regulated kinase, p38, and phosphatidylinositol 3-kinase (PI 3-kinase)/protein kinase B kinases only in CXCR3-A-transfected cells. These data indicate that the CXCR3 receptor is expressed by human type II pneumocytes, and the CXCR3-A splice variant mediates chemotactic responses possibly through Ca(2+) activation of both mitogen-activated protein kinase and PI 3-kinase signaling pathways. Expression of CXCR3 in alveolar epithelial cells may be important in pneumocyte repair from injury.

  18. Monocyte human leukocyte antigen-DR transcriptional downregulation by cortisol during septic shock.

    Science.gov (United States)

    Le Tulzo, Yves; Pangault, Celine; Amiot, Laurence; Guilloux, Valérie; Tribut, Olivier; Arvieux, Cédric; Camus, Christophe; Fauchet, Renée; Thomas, Rémi; Drénou, Bernard

    2004-05-15

    Monocyte deactivation has been identified as a major factor of immunosuppression in sepsis and is associated with a loss of surface human leukocyte antigen-DR (HLA-DR) expression on circulating monocytes. Using flow cytometry, quantitative reverse transcription-polymerase chain reaction, we investigated this phenomenon in septic patients. We confirmed the early loss of monocyte HLA-DR expression in all infected patients and demonstrated that this persistent lowered expression at Day 6 correlated with severity scores, secondary infection, and death. This phenomenon occurred at a transcriptional level via a decrease in the class II transactivator A (CIITA) transcription. Furthermore, these abnormalities correlated with the high cortisol levels observed in sepsis and not with those of other putative factors such as catecholamines or interleukin-10. Finally, in vitro studies evidenced that glucocorticoids decrease HLA-DR expression at a transcriptional level via a decrease in CIITA mRNA levels, mainly by down modulating its isoforms I and III. We conclude that in human sepsis, the loss of HLA-DR expression on circulating monocytes is associated with a poor outcome. We suggest that the high endogenous cortisol level observed in septic shock may be a possible new factor involved in the loss of HLA-DR expression on monocytes via its effect on HLA-DR and CIITA transcription.

  19. Mechanism of interferon-gamma production by monocytes stimulated with myeloperoxidase and neutrophil extracellular traps.

    Science.gov (United States)

    Yamaguchi, Rui; Kawata, Jin; Yamamoto, Toshitaka; Ishimaru, Yasuji; Sakamoto, Arisa; Ono, Tomomichi; Narahara, Shinji; Sugiuchi, Hiroyuki; Hirose, Eiji; Yamaguchi, Yasuo

    2015-08-01

    Neutrophil extracellular traps (NETs) have an important role in antimicrobial innate immunity and release substances that may modulate the immune response. We investigated the effects of soluble factors from NETs and neutrophil granule proteins on human monocyte function by using the Transwell system to prevent cell-cell contact. NET formation was induced by exposing human neutrophils to phorbol myristate acetate (PMA). When monocytes were incubated with PMA alone, expression of interleukin (IL)-4, IL-6, IL-8, and tumor necrosis factor (TNF)-alpha mRNA was upregulated, but IL-10, IL-12, and interferon (IFN)-gamma mRNA were not detected. Incubation of monocytes with NETs enhanced the expression of IL-10 and IFN-gamma mRNA, but not IL-12 mRNA. Myeloperoxidase stimulated IFN-gamma production by monocytes in a dose-dependent manner. Both a nuclear factor-kappaB inhibitor (PDTC) and an intracellular calcium antagonist (TMB-8) prevented upregulation of IFN-gamma production. Neither a combined p38alpha and p38beta inhibitor (SB203580) nor an extracellular signal-regulated kinase inhibitor (PD98059) suppressed IFN-gamma production. Interestingly, a combined p38gamma and p38delta inhibitor (BIRB796) significantly decreased IFN-gamma production. These findings suggest that myeloperoxidase induces IFN-gamma production by monocytes via p38gamma/delta mitogen-activated protein kinase.

  20. HIV-1-triggered release of type I IFN by plasmacytoid dendritic cells induces BAFF production in monocytes.

    Science.gov (United States)

    Gomez, Alejandro M; Ouellet, Michel; Tremblay, Michel J

    2015-03-01

    HIV-1 infection leads to numerous B cell abnormalities, including hypergammaglobulinemia, nonspecific B cell activation, nonspecific class switching, increased cell turnover, breakage of tolerance, increased immature/transitional B cells, B cell malignancies, as well as a loss of capacity to generate and maintain memory, all of which contribute to a global impairment of the immune humoral compartment. Several cytokines and soluble factors, which are increased in sera of HIV-1-infected individuals, have been suggested to directly or indirectly contribute to these B cell dysfunctions, and one of these is the B cell-activating factor (BAFF). We report in this study that HIV-1 (X4- and R5-tropic) upregulates BAFF expression and secretion by human monocytes. Moreover, we show that the virus-mediated production of BAFF by monocytes relies on a type I IFN response by a small percentage of plasmacytoid dendritic cells (pDCs) present in the monocyte cultures. HIV-1-induced type I IFN by pDCs triggers BAFF production in both classical and intermediate monocytes, but not in nonclassical monocytes, which nonetheless display a very strong basal BAFF production. We report also that basal BAFF secretion was higher in monocytes obtained from females compared with those from male donors. This study provides a novel mechanistic explanation for the increased BAFF levels observed during HIV-1 infection and highlights the importance of pDC/monocyte crosstalk to drive BAFF secretion. Copyright © 2015 by The American Association of Immunologists, Inc.

  1. Ex vivo foam cell formation is enhanced in monocytes from older individuals by both extrinsic and intrinsic mechanisms.

    Science.gov (United States)

    Angelovich, Thomas A; Shi, Margaret D Y; Zhou, Jingling; Maisa, Anna; Hearps, Anna C; Jaworowski, Anthony

    2016-07-01

    Aging is the strongest predictor of cardiovascular diseases such as atherosclerosis, which are the leading causes of morbidity and mortality in elderly men. Monocytes play an important role in atherosclerosis by differentiating into foam cells (lipid-laden macrophages) and producing atherogenic proinflammatory cytokines. Monocytes from the elderly have an inflammatory phenotype that may promote atherosclerotic plaque development; here we examined whether they are more atherogenic than those from younger individuals. Using an in vitro model of monocyte transmigration and foam cell formation, monocytes from older men (median age [range]: 75 [58-85] years, n=20) formed foam cells more readily than those of younger men (32 [23-46] years, n=20) (PFoam cell formation was enhanced by soluble factors in serum from older men, but did not correlate with plasma lipid levels. Of the three subsets, intermediate monocytes formed the most foam cells. Therefore, both cellular changes to monocytes and soluble plasma factors in older men primes monocytes for foam cell formation following transendothelial migration, which may contribute to enhanced atherosclerosis in this population.

  2. Galectin-3 Binding Protein Secreted by Breast Cancer Cells Inhibits Monocyte-Derived Fibrocyte Differentiation.

    Science.gov (United States)

    White, Michael J V; Roife, David; Gomer, Richard H

    2015-08-15

    To metastasize, tumor cells often need to migrate through a layer of collagen-containing scar tissue which encapsulates the tumor. A key component of scar tissue and fibrosing diseases is the monocyte-derived fibrocyte, a collagen-secreting profibrotic cell. To test the hypothesis that invasive tumor cells may block the formation of the fibrous sheath, we determined whether tumor cells secrete factors that inhibit monocyte-derived fibrocyte differentiation. We found that the human metastatic breast cancer cell line MDA-MB-231 secretes activity that inhibits human monocyte-derived fibrocyte differentiation, whereas less aggressive breast cancer cell lines secrete less of this activity. Purification indicated that Galectin-3 binding protein (LGALS3BP) is the active factor. Recombinant LGALS3BP inhibits monocyte-derived fibrocyte differentiation, and immunodepletion of LGALS3BP from MDA-MB 231 conditioned media removes the monocyte-derived fibrocyte differentiation-inhibiting activity. LGALS3BP inhibits the differentiation of monocyte-derived fibrocytes from wild-type mouse spleen cells, but not from SIGN-R1(-/-) mouse spleen cells, suggesting that CD209/SIGN-R1 is required for the LGALS3BP effect. Galectin-3 and galectin-1, binding partners of LGALS3BP, potentiate monocyte-derived fibrocyte differentiation. In breast cancer biopsies, increased levels of tumor cell-associated LGALS3BP were observed in regions of the tumor that were invading the surrounding stroma. These findings suggest LGALS3BP and galectin-3 as new targets to treat metastatic cancer and fibrosing diseases.

  3. Galectin-2 induces a proinflammatory, anti-arteriogenic phenotype in monocytes and macrophages.

    Directory of Open Access Journals (Sweden)

    Cansu Yıldırım

    Full Text Available Galectin-2 is a monocyte-expressed carbohydrate-binding lectin, for which increased expression is genetically determined and associated with decreased collateral arteriogenesis in obstructive coronary artery disease patients. The inhibiting effect of galectin-2 on arteriogenesis was confirmed in vivo, but the mechanism is largely unknown. In this study we aimed to explore the effects of galectin-2 on monocyte/macrophage phenotype in vitro and vivo, and to identify the receptor by which galectin-2 exerts these effects. We now show that the binding of galectin-2 to different circulating human monocyte subsets is dependent on monocyte surface expression levels of CD14. The high affinity binding is blocked by an anti-CD14 antibody but not by carbohydrates, indicating a specific protein-protein interaction. Galectin-2 binding to human monocytes modulated their transcriptome by inducing proinflammatory cytokines and inhibiting pro-arteriogenic factors, while attenuating monocyte migration. Using specific knock-out mice, we show that galectin-2 acts through the CD14/toll-like receptor (TLR-4 pathway. Furthermore, galectin-2 skews human macrophages to a M1-like proinflammatory phenotype, characterized by a reduced motility and expression of an anti-arteriogenic cytokine/growth factor repertoire. This is accompanied by a switch in surface protein expression to CD40-high and CD206-low (M1. In a murine model we show that galectin-2 administration, known to attenuate arteriogenesis, leads to increased numbers of CD40-positive (M1 and reduced numbers of CD206-positive (M2 macrophages surrounding actively remodeling collateral arteries. In conclusion galectin-2 is the first endogenous CD14/TLR4 ligand that induces a proinflammatory, non-arteriogenic phenotype in monocytes/macrophages. Interference with CD14-Galectin-2 interaction may provide a new intervention strategy to stimulate growth of collateral arteries in genetically compromised cardiovascular

  4. Acute monocytic leukemia in an irradiated beagle

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    Tolle, D.V.; Seed, T.M.; Fritz, T.E.; Lombard, L.S.; Poole, C.M.; Norris, W.P.

    1979-01-01

    A purebred female Beagle dog that had received 2,000 R of protracted whole-body ..gamma..-irradiation from /sup 60/Co when 14 months old had hematologic changes consistent with a myeloproliferative disorder 3 years after the termination of radiation exposure. Peripheral blood and bone marrow findings during the 7-month period before death showed progressive anemia with increased numbers of platelets; immature granulocytes, monocytes and promonocytes. A period of partial remission occurred during which time the peripheral blood was aleukemic, although there was marked thrombocytosis and abnormal erythropoiesis which was evidenced by bizarre circulating nucleated red cells, anisocytosis, poikilocytosis and Howell-Jolly bodies. The dog had a terminal crisis with marked leukocytosis, most cells in the peripheral blood being bizarre monocytes and promonocytes. Tissues obtained at necroscopy showed diffuse as well as focal infiltration of the spleen, liver, lymph nodes, heart, kidney and gastrointestinal wall with immature neoplastic cells resembling monocytes and monocytic precursors. The monocytic differentiation of the invasive cell population was confirmed by morphological, cytochemical, histological, ultrastructural and in vitro cell culture studies.

  5. NF-κB Mediated Transcription in Human Monocytic Cells and Endothelial Cells.

    Science.gov (United States)

    Parry, G C; Mackman, N

    1998-04-01

    Monocytes and endothelial cells become activated at sites of inflammation and contribute to the pathology of many diseases, including septic shock and atherosclerosis. In these cells, induction of genes expressing various inflammatory mediators, such as adhesion molecules, cytokines, and growth factors, is regulated by NF-κB/Rel transcription factors. Recent studies have identified components of the signal transduction pathways leading to the activation of NF-κB/Rel proteins. Inhibition of these signaling pathways provides a novel therapeutic approach to prevent inducible gene expression in both monocytes and endothelial cells. (Trends Cardiovasc Med 1998;8:138-142). © 1998, Elsevier Science Inc.

  6. A theoretical timeline for myocardial infarction: immunohistochemical evaluation and western blot quantification for Interleukin-15 and Monocyte chemotactic protein-1 as very early markers.

    Science.gov (United States)

    Turillazzi, Emanuela; Di Paolo, Marco; Neri, Margherita; Riezzo, Irene; Fineschi, Vittorio

    2014-07-02

    Experimental and human studies have demonstrated that innate immune mechanisms and consequent inflammatory reaction play a critical role in cardiac response to ischemic injury. Thus, the detection of immuno-inflammatory and cellular phenomena accompanying cardiac alterations during the early inflammatory phase of myocardial infarction (MI) may be an excellent diagnostic tool. Current knowledge of the chronology of the responses of myocardial tissue following the occurrence of ischemic insult, as well as the existence of numerous studies aiming to identify reliable markers in dating MI, induced us to investigate the myocardial specimens of MI fatal cases in order to better define the age of MI. We performed an immunohistochemical study and a Western blot analysis to evaluate detectable morphological changes in myocardial specimens of fatal MI cases and to quantify the effects of cardiac expression of inflammatory mediators (CD15, IL-1β, IL-6, TNF-α, IL-15, IL-8, MCP-1, ICAM-1, CD18, tryptase) and structural and functional cardiac proteins. We observed a biphasic course of MCP-1: it was strongly expressed in the very early phase (0-4 hrs), to diminish in the early period (after 6-8 hrs). Again, our choice of IL-15 is explained by the synergism with neutrophilic granulocytes (CD15) and our study shows the potential for striking cytokine synergy in promoting fast, local neutrophil response in damaged tissues. A progressively stronger immunoreaction for the CD15 antibody was visible in the areas where the margination of circulating inflammatory cells was detectable, up to very strong expression in the oldest ones (>12 hours). Further, the induction of CD15, IL-15, MCP-1 expression levels was quantified by Western blot analysis. The results were as follows: IL-15/β-actin 0.80, CD15/β-actin 0.30, and MCP-1/β-actin 0.60, matching perfectly with the results of immunohistochemistry. Control hearts from traumatic death cases did not show any immunoreactivity to the pro-inflammatory markers, neither were there any reactions in Western blot analysis. Essential markers (i.e. IL-15, MCP-1) are suitable indicators of myocardial response to ischemic insult involving very early phase reaction (inflammatory response and cytokine release). In the very near future, proteomics may help clinicians and pathologists to better understand mechanisms relating to cardiac repair and remodeling and provide targets for future therapies.

  7. Intracerebral GM-CSF contributes to transendothelial monocyte migration in APP/PS1 Alzheimer's disease mice.

    Science.gov (United States)

    Shang, De S; Yang, Yi M; Zhang, Hu; Tian, Li; Jiang, Jiu S; Dong, Yan B; Zhang, Ke; Li, Bo; Zhao, Wei D; Fang, Wen G; Chen, Yu H

    2016-11-01

    Although tight junctions between human brain microvascular endothelial cells in the blood-brain barrier prevent molecules or cells in the bloodstream from entering the brain, in Alzheimer's disease, peripheral blood monocytes can "open" these tight junctions and trigger subsequent transendothelial migration. However, the mechanism underlying this migration is unclear. Here, we found that the CSF2RB, but not CSF2RA, subunit of the granulocyte-macrophage colony-stimulating factor receptor was overexpressed on monocytes from Alzheimer's disease patients. CSF2RB contributes to granulocyte-macrophage colony-stimulating factor-induced transendothelial monocyte migration. Granulocyte-macrophage colony-stimulating factor triggers human brain microvascular endothelial cells monolayer tight junction disassembly by downregulating ZO-1 expression via transcription modulation and claudin-5 expression via the ubiquitination pathway. Interestingly, intracerebral granulocyte-macrophage colony-stimulating factor blockade abolished the increased monocyte infiltration in the brains of APP/PS1 Alzheimer's disease model mice. Our results suggest that in Alzheimer's disease patients, high granulocyte-macrophage colony-stimulating factor levels in the brain parenchyma and cerebrospinal fluid induced blood-brain barrier opening, facilitating the infiltration of CSF2RB-expressing peripheral monocytes across blood-brain barrier and into the brain. CSF2RB might be useful as an Alzheimer's disease biomarker. Thus, our findings will help to understand the mechanism of monocyte infiltration in Alzheimer's disease pathogenesis.

  8. Effects of Garlic Oil on the Migration of Neutrophil-Like Cell Studied by Using a Chemotactic Gradient Labchip

    Directory of Open Access Journals (Sweden)

    Po-Chen Shih

    2010-01-01

    Full Text Available We have designed and fabricated a novel chemotactic gradient Labchip for studying cell migration quantitatively. Owing to the great potential of garlic and its preparations in developing antiinflammatory drugs, the aim of the present study is to investigate the effect of garlic oil on the locomotion of a neutrophil-like cell by measuring the dynamic features of cell migration including migration direction, average migration speed, chemotactic index (CI, and motility index (MI with the newly designed Labchip. We found that garlic oil treatment lowered the values of CI and MI and reduced the average speed of cell migration from 13 to 8 μm/min. The results indicate that garlic oil is a potential inhibitor for neutrophil-like cell migration and chemotactic responsiveness. By comparing with the effects of nocodazole and cytochalasin B, we also suggest that the antiinflammatory activity exhibited by garlic oil was mainly through inhibiting the assembly-disassembly processes of the cytoskeleton.

  9. Expression of the cytochrome P450 epoxygenase CYP2J2 in human monocytic leukocytes.

    Science.gov (United States)

    Nakayama, Kaeko; Nitto, Takeaki; Inoue, Teruo; Node, Koichi

    2008-08-29

    CYP2J2 is one of the cytochrome P450 epoxygenases involved in the metabolism of arachidonic acid. CYP2J2 has been identified in several tissues, especially cardiovascular tissues. CYP2J2 has cardiovascular effects, as epoxyeicosatrienoic acid, one of its metabolites, has anti-inflammatory and vasodilative activities. We investigated the expression of CYP2J2 in human leukocytes using reverse transcription-polymerase chain reaction, immunoblotting and immunostaining. Human monocytic cells, but not human neutrophils, exhibited constitutive expression of CYP2J2. Furthermore, the expression of CYP2J2 mRNA increased when the human monocytic cell line THP-1 cells and human monocytes were stimulated with phorbol 12-myristate 13-acetate and macrophage-colony stimulating factor in combination with granulocyte/macrophage-colony stimulating factor, respectively. These results suggest that expression of CYP2J2 was up-regulated when human monocytes differentiated into macrophages and that human monocytic cells and macrophages have a pathway to metabolize arachidonic acid using CYP epoxygenases.

  10. Ability of Ni-containing biomedical alloys to activate monocytes and endothelial cells in vitro.

    Science.gov (United States)

    Wataha, J C; Lockwood, P E; Marek, M; Ghazi, M

    1999-06-05

    Nickel-containing alloys commonly are used in medical and dental applications that place them into long-term contact with soft tissues. The release of Ni ions from these alloys is disturbing because of the toxic, immunologic, and carcinogenic effects that have been documented for some Ni compounds. In particular, Ni ions in solution recently have been shown to cause expression of inflammatory mediators, such as interleukin-1beta (IL-1beta), tumor necrosis factor-alpha (TNF-alpha), and intercellular adhesion molecules (ICAMs) from keratinocytes, monocytes, and endothelial cells. However, the ability of the solid alloys themselves to induce these inflammatory effects has not been demonstrated. An in vitro system was used to determine if Ni-containing biomedical alloys could cause secretion of either IL-1beta or TNF-alpha from monocytes or expression of ICAMs on endothelial cells. Pure nickel, titanium, and three biomedical alloys-18-8 stainless steel, NiTi, and Rexillium III-were evaluated. First, it was determined whether or not the alloys or pure metals could cause cytotoxicity to THP-1 human monocytes or human microvascular endothelial cells (HMVECs) by measuring the succinic dehydrogenase (SDH) activity of the cells. Then, using identical conditions of exposure, the secretion of IL-1beta or TNF-alpha from monocytes or ICAM-1 expression on the HMVECs was determined. Only pure nickel suppressed (by 48% compared to Teflon controls) the SDH activity of the HMVECs or THP-1 monocytes. No alloy or metal caused the HMVECs to express ICAM-1, but the NiTi alloy caused a significant (ANOVA/Tukey) secretion of IL-1beta from the THP-1 monocytes. Secretion of TNF-alpha induced by NiTi was detectable but not statistically significant. The levels of IL-1beta secretion from monocytes were sufficient to induce ICAM-1 expression on HMVECs. The release of Ni from the NiTi was a logical suspect in causing the IL-1beta secretion by monocytes, but its role was not confirmed since other

  11. Distinct CCR7 glycosylation pattern shapes receptor signaling and endocytosis to modulate chemotactic responses.

    Science.gov (United States)

    Hauser, Mark A; Kindinger, Ilona; Laufer, Julia M; Späte, Anne-Katrin; Bucher, Delia; Vanes, Sarah L; Krueger, Wolfgang A; Wittmann, Valentin; Legler, Daniel F

    2016-06-01

    The homeostatic chemokines CCL19 and CCL21 and their common cognate chemokine receptor CCR7 orchestrate immune cell trafficking by eliciting distinct signaling pathways. Here, we demonstrate that human CCR7 is N-glycosylated on 2 specific residues in the N terminus and the third extracellular loop. Conceptually, CCR7 glycosylation adds steric hindrance to the receptor N terminus and extracellular loop 3, acting as a "swinging door" to regulate receptor sensitivity and cell migration. We found that freshly isolated human B cells, as well as expanded T cells, but not naïve T cells, express highly sialylated CCR7. Moreover, we identified that human dendritic cells imprint T cell migration toward CCR7 ligands by secreting enzymes that deglycosylate CCR7, thereby boosting CCR7 signaling on T cells, permitting enhanced T cell locomotion, while simultaneously decreasing receptor endocytosis. In addition, dendritic cells proteolytically convert immobilized CCL21 to a soluble form that is more potent in triggering chemotactic movement and does not desensitize the receptor. Furthermore, we demonstrate that soluble CCL21 functionally resembles neither the CCL19 nor the CCL21 phenotype but acts as a chemokine with unique features. Thus, we advance the concept of dendritic cell-dependent generation of micromilieus and lymph node conditioning by demonstrating a novel layer of CCR7 regulation through CCR7 sialylation. In summary, we demonstrate that leukocyte subsets express distinct patterns of CCR7 sialylation that contribute to receptor signaling and fine-tuning chemotactic responses.

  12. Computational modeling of chemotactic signaling and aggregation of microglia around implantation site during deep brain stimulation

    Science.gov (United States)

    Silchenko, A. N.; Tass, P. A.

    2013-10-01

    It is well established that prolonged electrical stimulation of brain tissue causes massive release of ATP in the extracellular space. The released ATP and the products of its hydrolysis, such as ADP and adenosine, become the main elements mediating chemotactic sensitivity and motility of microglial cells via subsequent activation of P2Y2,12 as well as A3A and A2A adenosine receptors. The size of the sheath around the electrode formed by the microglial cells is an important criterion for the optimization of the parameters of electrical current delivered to brain tissue. Here, we study a purinergic signaling pathway underlying the chemotactic motion of microglia towards the implanted electrode during deep brain stimulation. We present a computational model describing formation of a stable aggregate around the implantation site due to the joint chemo-attractive action of ATP and ADP together with a mixed influence of extracellular adenosine. The model was built in accordance with the classical Keller-Segel approach and includes an equation for the cells' density as well as equations describing the hydrolysis of extracellular ATP via successive reaction steps ATP →ADP →AMP →adenosine. The results of our modeling allowed us to reveal the dependence of the width of the encapsulating layer around the electrode on the amount of ATP released due to permanent electrical stimulation. The dependences of the aggregates' size on the parameter governing the nonlinearity of interaction between extracellular adenosine and adenosine receptors are also analyzed.

  13. An unusual protein kinase phosphorylates the chemotactic receptor of Dictystelium discoideum

    Energy Technology Data Exchange (ETDEWEB)

    Meier, K.; Klein, C. (St. Louis Univ. School of Medicine, MO (USA))

    1988-04-01

    The authors report the cAMP-dependent phosphorylation of the chemotactic receptor of Dictyostelium discoideum in partially purified plasma membranes. The protein kinase responsible for receptor phosphorylation is associated with this fraction and preferentially phosphorylates the ligand-occupied form of the receptor. 8-Azido({sup 32}P)cAMP labeling of the cell surface has shown that the cAMP receptor exists in two forms. A 45-kDa protein is predominant on unstimulated cells. cAMP stimulation results in an increased receptor phosphorylation such that the receptor migrates on NaDodSO{sub 4}/PAGE as a 47-kDa protein. Phosphorylation of the chemotactic receptor is not detected in membrane preparations unless cAMP is added to the incubation mixture. Only under those conditions is the phosphorylated 47-kDa form observed. The requirement for cAMP reflects the fact that the kinase involved preferentially uses the ligand-occupied receptor as a substrate. In vitro phosphorylation of the receptor does not involve tyrosine residues. The enzyme does not appear to be a cAMP- or cGMP-dependent protein kinase nor is it sensitive to guanine nucleotides, Ca{sup 2+}/calmodulin, Ca{sup 2+}/phospholipid, or EGTA. Similarities with the {beta}-adrenergic receptor protein kinase are discussed.

  14. Chemotactic behavior of deep subsurface bacteria toward carbohydrates, amino acids and a chlorinated alkene

    Energy Technology Data Exchange (ETDEWEB)

    Lopez de Victoria, G. (Puerto Rico Univ., Rio Piedras (Puerto Rico). Dept. of Biology)

    1989-02-01

    The chemotactic behavior of deep terrestrial subsurface bacteria toward amino acids, carbohydrates and trichloroethylene was assayed using a modification of the capillary method and bacterial enumeration by acridine orange direct counts. Eleven isolates of bacteria isolated from six different geological formations were investigated. A bimodal response rather than an absolute positive or negative response was observed in most assays. Most of the isolates were positively chemotactic to low concentrations of substrates and were repelled by high concentrations of the same substrate. However, this was not the case for trichloroethylene (TCE) which was mostly an attractant and elicited the highest responses in all the isolates when compared with amino acids and carbohydrates. The movement rates of these isolates in aseptic subsurface sediments in the absence and presence of TCE were also determined using a laboratory model. All of the isolates showed distinct response range, peak, and threshold concentrations when exposed to the same substrates suggesting that they are possibly different species as has been inferred from DNA homology studies. 101 refs., 4 figs., 57 tabs.

  15. Chemotactic sensing towards ambient and secreted attractant drives collective behaviour of E. coli.

    Directory of Open Access Journals (Sweden)

    Tine Curk

    Full Text Available We simulate the dynamics of a suspension of bacterial swimmers, which chemotactically sense gradients in either ambient or self-secreted attractants (e.g. nutrient or aspartate respectively, or in both. Unlike previous mean field models based on a set of continuum partial differential equations, our model resolves single swimmers and therefore incorporates stochasticity and effects due to fluctuations in the bacterial density field. The algorithm we use is simple enough that we can follow the evolution of colonies of up to over a million bacteria for timescales relevant to pattern formation for E. coli growing in semisolid medium such as agar, or in confined geometries. Our results confirm previous mean field results that the patterns observed experimentally can be reproduced with a model incorporating chemoattractant secretion, chemotaxis (towards gradients in the chemoattractant field, and bacterial reproduction. They also suggest that further experiments with bacterial strains chemotactically moving up both nutrient and secreted attractant field may yield yet more dynamical patterns.

  16. INTERLEUKIN-4 PREVENTS THE INDUCTION OF G-CSF MESSENGER-RNA IN HUMAN ADHERENT MONOCYTES IN RESPONSE TO ENDOTOXIN AND IL-1 STIMULATION

    NARCIS (Netherlands)

    VELLENGA, E; DOKTER, W; DEWOLF, JTM; VANDEVINNE, B; ESSELINK, MT; HALIE, MR

    Human recombinant interleukin-4 (IL-4) was studied for its effects on the expression of granulocyte-colony stimulating factor (G-CSF) mRNA in human adherent monocytes in the absence and presence of endotoxin and interleukin 1 (IL-1). IL-4 (15 ng/ml) did not induce G-CSF transcripts in monocytes but

  17. Regulation of nutrition-associated receptors in blood monocytes of normal weight and obese humans.

    Science.gov (United States)

    Pivovarova, Olga; Hornemann, Silke; Weimer, Sandra; Lu, Ye; Murahovschi, Veronica; Zhuk, Sergei; Seltmann, Anne-Cathrin; Malashicheva, Anna; Kostareva, Anna; Kruse, Michael; Busjahn, Andreas; Rudovich, Natalia; Pfeiffer, Andreas F H

    2015-03-01

    Obesity, type 2 diabetes and associated metabolic diseases are characterized by low-grade systemic inflammation which involves interplay of nutrition and monocyte/macrophage functions. We suggested that some factors such as nutrient components, neuropeptides involved in the control of gastrointestinal functions, and gastrointestinal hormones might influence immune cell functions and in this way contribute to the disease pathogenesis. The aim of this study was to investigate the mRNA expression of twelve nutrition-associated receptors in peripheral blood mononuclear cells (PBMC), isolated monocytes and monocyte-derived macrophages and their regulation under the switching from the high-carbohydrate low-fat diet to the low-carbohydrate high-fat (LC/HFD) isocaloric diet in healthy humans. The mRNA expression of receptors for short chain fatty acids (GPR41, GPR43), bile acids (TGR5), incretins (GIPR, GLP1R), cholecystokinin (CCKAR), neuropeptides VIP and PACAP (VIPR1, VIPR2), and neurotensin (NTSR1) was detected in PBMC and monocytes, while GPR41, GPR43, GIPR, TGR5, and VIPR1 were found in macrophages. Correlations of the receptor expression in monocytes with a range of metabolic and inflammatory markers were found. In non-obese subjects, the dietary switch to LC/HFD induced the increase of GPR43 and VIPR1 expression in monocytes. No significant differences of receptor expression between normal weight and moderately obese subjects were found. Our study characterized for the first time the expression pattern of nutrition-associated receptors in human blood monocytes and its dietary-induced changes linking metabolic responses to nutrition with immune functions in health and metabolic diseases. Copyright © 2015 Elsevier Inc. All rights reserved.

  18. A new role for monocytes in modulating myometrial inflammation during human labor.

    Science.gov (United States)

    Srikhajon, Khetsopon; Shynlova, Oksana; Preechapornprasert, Anyarin; Chanrachakul, Boonsri; Lye, Stephen

    2014-07-01

    Here we fully characterize the cytokine profile of laboring human myometrium using Luminex analysis of 48 cytokine proteins, and stereologically quantified infiltration of monocytes and neutrophils into the myometrium. We hypothesized that monocytes can regulate their accumulation in the myometrium by disruption of proinflammatory cytokines to prevent an uncontrolled inflammatory response after labor onset. We isolated primary human myometrial cells (HMCs) from term, nonlaboring myometrial biopsies. Confluent HMCs were cocultured directly with human monocytic (THP-1) or lymphocytic (U937) cells, and with the same cells spatially separated by a membrane insert. After 72 h, HMCs and THP-1 were harvested separately, and RNA was extracted and analyzed by quantitative PCR. Coculture supernatants were collected and analyzed by Luminex assay and ELISA. We found that the laboring human myometrium produces significantly higher amounts of interleukin (IL) 6, IL9, IL18, IL1RA, CCL2, CCL7, CXCL8, CSF3, and tumor necrosis factor alpha, which coincides with the influx of immune cells. The direct contact or presence of THP-1 monocytes (but not U937 cells) significantly decreased CCL2 protein levels and increased IL1RA protein levels secreted by HMCs. This time-dependent decrease of CCL2 was greater with increasing number of monocytes being in direct contact with HMCs. We suggest a novel mechanism by which monocytes are first recruited to the myometrium by multiple cytokines and contribute to the physiologic inflammation of labor. After completing transmigration, activated monocytes disrupt locally established CCL2 gradients (possible by CCR2-mediated consumption) to limit their accumulation in the uterus. This mechanism may serve as a negative feedback loop to control the local inflammation and promote a return to homeostasis. © 2014 by the Society for the Study of Reproduction, Inc.

  19. Interleukin 18 stimulates HIV type 1 in monocytic cells.

    Science.gov (United States)

    Shapiro, L; Puren, A J; Barton, H A; Novick, D; Peskind, R L; Shenkar, R; Gu, Y; Su, M S; Dinarello, C A

    1998-10-13

    The cytokine interleukin (IL) 18 (formerly interferon gamma-inducing factor) induces the T helper type 1 response. In the present studies, IL-18 increased HIV type 1 (HIV-1) production from 5- to 30-fold in the chronically infected U1 monocytic cell line. Inhibition of tumor necrosis factor (TNF) activity by the addition of TNF-binding protein reduced IL-18-stimulated HIV-1 production by 48%. In the same cultures, IL-18-induced IL-8 was inhibited by 96%. Also, a neutralizing anti-IL-6 mAb reduced IL-18-induced HIV-1 by 63%. Stimulation of U1 cells with IL-18 resulted in increased production of IL-6, and exogenous IL-6 added to U1 cells increased HIV-1 production 4-fold over control. A specific inhibitor of the p38 mitogen-activated protein kinase reduced IL-18-induced HIV-1 by 73%, and a 50% inhibition was observed at 0.05 microM. In the same cultures, IL-8 was inhibited by 87%. By gel-shift and supershift analyses, increased binding activity of the transcription factor NF-kappaB was measured in nuclear extracts from U1 cells 1 h after exposure to IL-18. These results demonstrate induction of HIV-1 by IL-18 in a monocyte target associated with an intermediate role for TNF and IL-6, activation of p38 mitogen-activated protein kinase, and nuclear translocation of NF-kappaB.

  20. Ca2+/calmodulin-dependent kinase kinase alpha is expressed by monocytic cells and regulates the activation profile.

    Directory of Open Access Journals (Sweden)

    Christopher B Guest

    Full Text Available Macrophages are capable of assuming numerous phenotypes in order to adapt to endogenous and exogenous challenges but many of the factors that regulate this process are still unknown. We report that Ca(2+/calmodulin-dependent kinase kinase alpha (CaMKKalpha is expressed in human monocytic cells and demonstrate that its inhibition blocks type-II monocytic cell activation and promotes classical activation. Affinity chromatography with paramagnetic beads isolated an approximately 50 kDa protein from nuclear lysates of U937 human monocytic cells activated with phorbol-12-myristate-13-acetate (PMA. This protein was identified as CaMKKalpha by mass spectrometry and Western analysis. The function of CaMKKalpha in monocyte activation was examined using the CaMKKalpha inhibitors (STO-609 and forskolin and siRNA knockdown. Inhibition of CaMKKalpha, enhanced PMA-dependent CD86 expression and reduced CD11b expression. In addition, inhibition was associated with decreased translocation of CaMKKalpha to the nucleus. Finally, to further examine monocyte activation profiles, TNFalpha and IL-10 secretion were studied. CaMKKalpha inhibition attenuated PMA-dependent IL-10 production and enhanced TNFalpha production indicating a shift from type-II to classical monocyte activation. Taken together, these findings indicate an important new role for CaMKKalpha in the differentiation of monocytic cells.

  1. Pregnancy and Preeclampsia Affect Monocyte Subsets in Humans and Rats

    NARCIS (Netherlands)

    Melgert, Barbro N.; Spaans, Floor; Borghuis, Theo; Klok, Pieter A.; Groen, Bart; Bolt, Annemarie; de Vos, P.; van Pampus, Maria; Wong, Tsz Y.; van Goor, Harry; Bakker, Winston W.; Faas, Marijke M.

    2012-01-01

    Introduction: Both nonclassical and intermediate monocytes have been implicated in different inflammatory conditions. We hypothesized that these monocytes would increase during pregnancy, a condition associated with generalized activation of inflammatory responses and that they would increase even

  2. Cathepsin K cleavage of SDF-1α inhibits its chemotactic activity towards glioblastoma stem-like cells.

    Science.gov (United States)

    Hira, Vashendriya V V; Verbovšek, Urška; Breznik, Barbara; Srdič, Matic; Novinec, Marko; Kakar, Hala; Wormer, Jill; der Swaan, Britt Van; Lenarčič, Brigita; Juliano, Luiz; Mehta, Shwetal; Van Noorden, Cornelis J F; Lah, Tamara T

    2017-03-01

    Glioblastoma (GBM) is the most aggressive primary brain tumor with poor patient survival that is at least partly caused by malignant and therapy-resistant glioma stem-like cells (GSLCs) that are protected in GSLC niches. Previously, we have shown that the chemo-attractant stromal-derived factor-1α (SDF-1α), its C-X-C receptor type 4 (CXCR4) and the cysteine protease cathepsin K (CatK) are localized in GSLC niches in glioblastoma. Here, we investigated whether SDF-1α is a niche factor that through its interactions with CXCR4 and/or its second receptor CXCR7 on GSLCs facilitates their homing to niches. Furthermore, we aimed to prove that SDF-1α cleavage by CatK inactivates SDF-1α and inhibits the invasion of GSLCs. We performed mass spectrometric analysis of cleavage products of SDF-1α after proteolysis by CatK. We demonstrated that CatK cleaves SDF-1α at 3 sites in the N-terminus, which is the region of SDF-1α that binds to its receptors. Confocal imaging of human GBM tissue sections confirmed co-localization of SDF-1α and CatK in GSLC niches. In accordance, 2D and 3D invasion experiments using CXCR4/CXCR7-expressing GSLCs and GBM cells showed that SDF-1α had chemotactic activity whereas CatK cleavage products of SDF-1α did not. Besides, CXCR4 inhibitor plerixafor inhibited invasion of CXCR4/CXCR7-expressing GSLCs. In conclusion, CatK can cleave and inactivate SDF-1α. This implies that CatK activity facilitates migration of GSLCs out of niches. We propose that activation of CatK may be a promising strategy to prevent homing of GSLCs in niches and thus render these cells sensitive to chemotherapy and radiation.

  3. Antibody Array-Generated Profiles of Cytokine Release from THP-1 Leukemic Monocytes Exposed to Different Amphotericin B Formulations

    OpenAIRE

    Turtinen, Lloyd W.; Prall, David N.; Bremer, Lindsay A.; Nauss, Rachel E.; Hartsel, Scott C.

    2004-01-01

    Cytokine antibody arrays were used to establish the profiles of cytokine release from THP-1 monocytes exposed to different amphotericin B (AMB) drug delivery systems. Fungizone (FZ) and Amphotec (ABCD) caused the release of significantly more inflammatory molecules and the release of inflammatory molecules at higher levels than either AmBisome (L-AMB) or Abelcet (ABLC) after 6 h of treatment. Specifically, tumor necrosis factor alpha (TNF-α), interleukin-8 (IL-8), GRO-(αβγ), monocyte chemoatt...

  4. Patrolling Monocytes Control Tumor Metastasis to the Lung

    OpenAIRE

    Hanna, Richard N.; Cekic, Caglar; Sag, Duygu; Tacke, Robert; Graham D. Thomas; Nowyhed, Heba; Herrley, Erica; Rasquinha, Nicole; McArdle, Sara; Wu, Runpei; Peluso, Esther; Metzger, Daniel; Ichinose, Hiroshi; Shaked, Iftach; Chodaczek, Grzegorz

    2015-01-01

    The immune system plays an important role in regulating tumor growth and metastasis. For example, classical monocytes promote tumorigenesis and cancer metastasis; however, how nonclassical “patrolling” monocytes interact with tumors is unknown. Here we show that patrolling monocytes are enriched in the microvasculature of the lung and reduce tumor metastasis to lung in multiple mouse metastatic tumor models. Nr4a1-deficient mice, which specifically lack patrolling monocytes, showed increased ...

  5. Altered monocyte and fibrocyte phenotype and function in scleroderma interstitial lung disease: reversal by caveolin-1 scaffolding domain peptide.

    Science.gov (United States)

    Tourkina, Elena; Bonner, Michael; Oates, James; Hofbauer, Ann; Richard, Mathieu; Znoyko, Sergei; Visconti, Richard P; Zhang, Jing; Hatfield, Corey M; Silver, Richard M; Hoffman, Stanley

    2011-07-01

    Interstitial lung disease (ILD) is a major cause of morbidity and mortality in scleroderma (systemic sclerosis, or SSc). Fibrocytes are a monocyte-derived cell population implicated in the pathogenesis of fibrosing disorders. Given the recently recognized importance of caveolin-1 in regulating function and signaling in SSc monocytes, in the present study we examined the role of caveolin-1 in the migration and/or trafficking and phenotype of monocytes and fibrocytes in fibrotic lung disease in human patients and an animal model. These studies fill a gap in our understanding of how monocytes and fibrocytes contribute to SSc-ILD pathology. We found that C-X-C chemokine receptor type 4-positive (CXCR4+)/collagen I-positive (ColI+), CD34+/ColI+ and CD45+/ColI+ cells are present in SSc-ILD lungs, but not in control lungs, with CXCR4+ cells being most prevalent. Expression of CXCR4 and its ligand, stromal cell-derived factor 1 (CXCL12), are also highly upregulated in SSc-ILD lung tissue. SSc monocytes, which lack caveolin-1 and therefore overexpress CXCR4, exhibit almost sevenfold increased migration toward CXCL12 compared to control monocytes. Restoration of caveolin-1 function by administering the caveolin scaffolding domain (CSD) peptide reverses this hypermigration. Similarly, transforming growth factor β-treated normal monocytes lose caveolin-1, overexpress CXCR4 and exhibit 15-fold increased monocyte migration that is CSD peptide-sensitive. SSc monocytes exhibit a different phenotype than normal monocytes, expressing high levels of ColI, CD14 and CD34. Because ColI+/CD14+ cells are prevalent in SSc blood, we looked for such cells in lung tissue and confirmed their presence in SSc-ILD lungs but not in normal lungs. Finally, in the bleomycin model of lung fibrosis, we show that CSD peptide diminishes fibrocyte accumulation in the lungs. Our results suggest that low caveolin-1 in SSc monocytes contributes to ILD via effects on cell migration and phenotype and that the

  6. Altered monocyte and fibrocyte phenotype and function in scleroderma interstitial lung disease: reversal by caveolin-1 scaffolding domain peptide

    Directory of Open Access Journals (Sweden)

    Tourkina Elena

    2011-07-01

    Full Text Available Abstract Interstitial lung disease (ILD is a major cause of morbidity and mortality in scleroderma (systemic sclerosis, or SSc. Fibrocytes are a monocyte-derived cell population implicated in the pathogenesis of fibrosing disorders. Given the recently recognized importance of caveolin-1 in regulating function and signaling in SSc monocytes, in the present study we examined the role of caveolin-1 in the migration and/or trafficking and phenotype of monocytes and fibrocytes in fibrotic lung disease in human patients and an animal model. These studies fill a gap in our understanding of how monocytes and fibrocytes contribute to SSc-ILD pathology. We found that C-X-C chemokine receptor type 4-positive (CXCR4+/collagen I-positive (ColI+, CD34+/ColI+ and CD45+/ColI+ cells are present in SSc-ILD lungs, but not in control lungs, with CXCR4+ cells being most prevalent. Expression of CXCR4 and its ligand, stromal cell-derived factor 1 (CXCL12, are also highly upregulated in SSc-ILD lung tissue. SSc monocytes, which lack caveolin-1 and therefore overexpress CXCR4, exhibit almost sevenfold increased migration toward CXCL12 compared to control monocytes. Restoration of caveolin-1 function by administering the caveolin scaffolding domain (CSD peptide reverses this hypermigration. Similarly, transforming growth factor β-treated normal monocytes lose caveolin-1, overexpress CXCR4 and exhibit 15-fold increased monocyte migration that is CSD peptide-sensitive. SSc monocytes exhibit a different phenotype than normal monocytes, expressing high levels of ColI, CD14 and CD34. Because ColI+/CD14+ cells are prevalent in SSc blood, we looked for such cells in lung tissue and confirmed their presence in SSc-ILD lungs but not in normal lungs. Finally, in the bleomycin model of lung fibrosis, we show that CSD peptide diminishes fibrocyte accumulation in the lungs. Our results suggest that low caveolin-1 in SSc monocytes contributes to ILD via effects on cell migration and

  7. Ranitidine improves postoperative monocyte and neutrophil function

    DEFF Research Database (Denmark)

    Nielsen, Hans Jørgen; Nielsen, H; Jensen, S;

    1994-01-01

    BACKGROUND: The histamine H2-receptor antagonist ranitidine hydrochloride has been shown to improve trauma-, blood transfusion-, and sepsis-induced immunosuppression. OBJECTIVE: To evaluate the effect of ranitidine on postoperative impairment in monocyte and neutrophil function. METHODS: Twenty...... difference (P detected. There were no infectious complications in ranitidine-treated patients. CONCLUSION: These results support previous studies...

  8. Fatal Monocytic Ehrlichiosis in Woman, Mexico, 2013

    Science.gov (United States)

    Sosa-Gutierrez, Carolina G.; Solorzano-Santos, Fortino; Walker, David H.; Torres, Javier; Serrano, Carlos A.

    2016-01-01

    Human monocytic ehrlichiosis is a febrile illness caused by Ehrlichia chaffeensis, an intracellular bacterium transmitted by ticks. In Mexico, a case of E. chaffeensis infection in an immunocompetent 31-year-old woman without recognized tick bite was fatal. This diagnosis should be considered for patients with fever, leukopenia, thrombocytopenia, and elevated liver enzyme levels. PMID:27088220

  9. Ranitidine improves postoperative monocyte and neutrophil function

    DEFF Research Database (Denmark)

    Nielsen, Hans Jørgen; Nielsen, H; Jensen, S

    1994-01-01

    BACKGROUND: The histamine H2-receptor antagonist ranitidine hydrochloride has been shown to improve trauma-, blood transfusion-, and sepsis-induced immunosuppression. OBJECTIVE: To evaluate the effect of ranitidine on postoperative impairment in monocyte and neutrophil function. METHODS: Twenty...... difference (P detected. There were no infectious complications in ranitidine-treated patients. CONCLUSION: These results support previous studies...

  10. Effect of HSV-2 Infected Monocytes on the Production of TNF- α and IL-6

    Institute of Scientific and Technical Information of China (English)

    敖俊红; 周礼义; 陈兴平; 杨蓉娅; 王文玲

    2003-01-01

    Objectiwe: In order to detect the role of monocytes in HSV-2 infection, we studied the effect of herpes sim-plex Virus-2 infection on the production of tumor ne-crosis factor (TNF- α ), interleukin-6 (IL-6) secreted by monocytes. Methods: Monocytes were infected by HSV-2 (333 Strain). Culture supernatants were collected at 1, 3,5, 7 days post-infection. The levels of TNF- α, IL-6 were measured by enzyme-linked immunosorbent as-say (ELISA). Results: The levels of TNF- α secretion by mono-cytes significantly decreased on first day post-infection. The levels of IL-6 significantly decreased on first and third days post-infection, and then gradu-ally increased to the control on seventh day post-infection.Conclusions: TNF- α and IL-6 production by mono-cytes was inhibited during HSV-2 infection. The pro-duction of cytokines may play an important role in herpes simplex viurs-2 pathogenicity and immunity.

  11. Altered monocyte activation markers in Tourette’s syndrome: a case–control study

    Directory of Open Access Journals (Sweden)

    Matz Judith

    2012-05-01

    Full Text Available Abstract Background Infections and immunological processes are likely to be involved in the pathogenesis of Tourette’s syndrome (TS. To determine possible common underlying immunological mechanisms, we focused on innate immunity and studied markers of inflammation, monocytes, and monocyte-derived cytokines. Methods In a cross-sectional study, we used current methods to determine the number of monocytes and levels of C-reactive protein (CRP in 46 children, adolescents, and adult patients suffering from TS and in 43 healthy controls matched for age and sex. Tumor necrosis factor alpha (TNF-alpha, interleukin 6 (IL-6, soluble CD14 (sCD14, IL1-receptor antagonist (IL1-ra, and serum neopterin were detected by immunoassays. Results We found that CRP and neopterin levels and the number of monocytes were significantly higher in TS patients than in healthy controls. Serum concentrations of TNF-alpha, sIL1-ra, and sCD14 were significantly lower in TS patients. All measured values were within normal ranges and often close to detection limits. Conclusions The present results point to a monocyte dysregulation in TS. This possible dysbalance in innate immunity could predispose to infections or autoimmune reactions.

  12. Decreased production of proinflammatory cytokines by monocytes from individuals presenting Candida-associated denture stomatitis.

    Science.gov (United States)

    Pinke, Karen Henriette; Freitas, Patrícia; Viera, Narciso Almeida; Honório, Heitor Marques; Porto, Vinicius Carvalho; Lara, Vanessa Soares

    2016-01-01

    Candida-associated denture stomatitis (DS) is the most frequent lesion among denture wearers, especially the elderly. DS is strongly associated with Candida albicans, as well as local and systemic factors, such as impaired immune response. Monocytes are important in the protective immune response against the fungus by the production of cytokines that recruit and activate leukocytes. There are functional changes in these cells with age, and individual alterations involving monocyte response may predispose the host to developing infections by Candida spp. In this study, our aim was to evaluate the production of TNF-α, IL-6, CXCL8, IL-1β, MCP-1 and IL-10 by monocytes from elderly denture wearers with/without DS and elderly or young non-denture wearers. We detected that monocytes from elderly denture wearers with Candida-related denture stomatitis produced lower levels of CXCL-8, IL-6 and MCP-1. This imbalance in cytokine levels was observed in spontaneous or LPS-stimulated production. Therefore, our data suggested that inherent aspects of the host, such as changes in cytokine production by monocytes, might be associated with the development and the persistence of DS irrespective of aging. Copyright © 2015 Elsevier Ltd. All rights reserved.

  13. A System Dynamics Model to Predict the Human Monocyte Response to Endotoxins

    Directory of Open Access Journals (Sweden)

    Enrique Álvarez

    2017-08-01

    Full Text Available System dynamics is a powerful tool that allows modeling of complex and highly networked systems such as those found in the human immune system. We have developed a model that reproduces how the exposure of human monocytes to lipopolysaccharides (LPSs induces an inflammatory state characterized by high production of tumor necrosis factor alpha (TNFα, which is rapidly modulated to enter into a tolerant state, known as endotoxin tolerance (ET. The model contains two subsystems with a total of six states, seven flows, two auxiliary variables, and 14 parameters that interact through six differential and nine algebraic equations. The parameters were estimated and optimized to obtain a model that fits the experimental data obtained from human monocytes treated with various LPS doses. In contrast to publications on other animal models, stimulation of human monocytes with super-low-dose LPSs did not alter the response to a second LPSs challenge, neither inducing ET, nor enhancing the inflammatory response. Moreover, the model confirms the low production of TNFα and increased levels of C–C motif ligand 2 when monocytes exhibit a tolerant state similar to that of patients with sepsis. At present, the model can help us better understand the ET response and might offer new insights on sepsis diagnostics and prognosis by examining the monocyte response to endotoxins in patients with sepsis.

  14. Endothelial microparticles (EMP) bind and activate monocytes: elevated EMP-monocyte conjugates in multiple sclerosis.

    Science.gov (United States)

    Jy, Wenche; Minagar, Alireza; Jimenez, Joaquin J; Sheremata, William A; Mauro, Lucia M; Horstman, Lawrence L; Bidot, Carlos; Ahn, Yeon S

    2004-09-01

    Elevated plasma endothelial microparticles (EMP) have been documented in MS during exacerbation. However, the role of EMP in pathogenesis of MS remains unclear. We investigated the formation of EMP-monocyte conjugates (EMP-MoC) and their potential role in transendothelial migration of inflammatory cells in MS. EMP-MoC were assayed in 30 MS patients in exacerbation, 20 in remission and in 35 controls. EMP-leukocyte conjugation was investigated flowcytometrically by employing alpha-CD54 or alpha-CD62E for EMP, and alpha-CD45 for leukocytes. EMP-MoC were characterized by identifying adhesion molecules involved and their effect on monocyte function. In vivo (clinical): EMP-MoC were markedly elevated in exacerbation vs. remission and controls, correlating with presence of GD+ MRI lesions. Free CD54+ EMP were not elevated but free CD62E+ EMP were. In vitro: EMP bound preferentially to monocytes, less to neutrophils, but little to lymphocytes. Bound EMP activated monocytes: CD11b expression increased 50% and migration through cerebral endothelial cell layer increased 2.6-fold. Blockade of CD54 reduced binding by 80%. Most CD54+ EMP bound to monocytes, leaving little free EMP, while CD62+ EMP were found both free and bound. These results demonstrated that phenotypic subsets of EMP interacted differently with monocytes. Based on our observations, EMP may enhance inflammation and increase transendothelial migration of monocytes in MS by binding to and activating monocytes through CD54. EMP-MoC were markedly increased in MS patients in exacerbation compared to remission and may serve as a sensitive marker of MS disease activity.

  15. A model for cell type localization in the migrating slug of Dictyostelium discoideum based on differential chemotactic sensitivity to cAMP and differential sensitivity to suppression of chemotaxis by ammonia

    Indian Academy of Sciences (India)

    Ira N Feit; Jeffrey Pawlikowski; Caroline Zawilski

    2007-03-01

    The three basic cell types in the migrating slug of Dictyostelium discoideum show differential chemotactic response to cyclic AMP (cAMP) and differential sensitivity to suppression of the chemotaxis by ammonia. The values of these parameters indicate a progressive maturation of chemotactic properties during the transdifferentiation of slug cell types. We present a model that explains the localization of the three cell types within the slug based on these chemotactic differences and on the maturation of their chemotactic properties.

  16. TLR4-mediated expression of Mac-1 in monocytes plays a pivotal role in monocyte adhesion to vascular endothelium.

    Science.gov (United States)

    Lee, Seung Jin; Choi, Eun Kyoung; Seo, Kyo Won; Bae, Jin Ung; Park, So Youn; Kim, Chi Dae

    2014-01-01

    Toll-like receptor 4 (TLR4) is known to mediate monocyte adhesion to endothelial cells, however, its role on the expression of monocyte adhesion molecules is unclear. In the present study, we investigated the role of TLR4 on the expression of monocyte adhesion molecules, and determined the functional role of TLR4-induced adhesion molecules on monocyte adhesion to endothelial cells. When THP-1 monocytes were stimulated with Kdo2-Lipid A (KLA), a specific TLR4 agonist, Mac-1 expression was markedly increased in association with an increased adhesion of monocytes to endothelial cells. These were attenuated by anti-Mac-1 antibody, suggesting a functional role of TLR4-induced Mac-1 on monocyte adhesion to endothelial cells. In monocytes treated with MK886, a 5-lipoxygenase (LO) inhibitor, both Mac-1 expression and monocyte adhesion to endothelial cells induced by KLA were markedly attenuated. Moreover, KLA increased the expression of mRNA and protein of 5-LO, suggesting a pivotal role of 5-LO on these processes. In in vivo studies, KLA increased monocyte adhesion to aortic endothelium of wild-type (WT) mice, which was attenuated in WT mice treated with anti-Mac-1 antibody as well as in TLR4-deficient mice. Taken together, TLR4-mediated expression of Mac-1 in monocytes plays a pivotal role on monocyte adhesion to vascular endothelium, leading to increased foam cell formation in the development of atherosclerosis.

  17. Boc SPPS of two hydrophobic peptides using a ''solubilising tail'' strategy : Dodecaalanine and chemotactic protein 10(42-55)

    NARCIS (Netherlands)

    Englebretsen, DR; Alewood, PF

    1996-01-01

    The solid phase syntheses of the hydrophobic peptides dodecaalanine and chemotactic protein-10(42-55) were achieved using a ''solubilising tail'' strategy. Peptide constructs of the form H-hydrophobic peptide-glycolamide ester-(Gly-Arg)(4)-Gly-OH were synthesised by Boc SPPS. The peptide-constructs

  18. Promotion of formyl peptide receptor 1-mediated neutrophil chemotactic migration by antimicrobial peptides isolated from the centipede Scolopendra subspinipes mutilans.

    Science.gov (United States)

    Park, Yoo Jung; Lee, Sung Kyun; Jung, Young Su; Lee, Mingyu; Lee, Ha Young; Kim, Sang Doo; Park, Joon Seong; Koo, JaeHyung; Hwang, Jae Sam; Bae, Yoe-Sik

    2016-09-01

    We investigated the effects of two antimicrobial peptides (AMPs) isolated from Scolopendra subspinipes mutilans on neutrophil activity. Stimulation of mouse neutrophils with the two AMPs elicited chemotactic migration of the cells in a pertussis toxin-sensitive manner. The two AMPs also stimulated activation of ERK and Akt, which contribute to chemotactic migration of neutrophils. We found that AMP-stimulated neutrophil chemotaxis was blocked by a formyl peptide receptor (FPR) 1 antagonist (cyclosporin H); moreover the two AMPs stimulated the chemotactic migration of FPR1-expressing RBL-2H3 cells but not of vector-expressing RBL-2H3 cells. We also found that the two AMPs stimulate neutrophil migration in vivo, and that this effect is blocked in FPR1-deficient mice. Taken together, our results suggest that the two AMPs stimulate neutrophils, leading to chemotactic migration through FPR1, and the two AMPs will be useful for the study of FPR1 signaling and neutrophil activation. [BMB Reports 2016; 49(9): 520-525].

  19. Boc SPPS of two hydrophobic peptides using a ''solubilising tail'' strategy : Dodecaalanine and chemotactic protein 10(42-55)

    NARCIS (Netherlands)

    Englebretsen, DR; Alewood, PF

    1996-01-01

    The solid phase syntheses of the hydrophobic peptides dodecaalanine and chemotactic protein-10(42-55) were achieved using a ''solubilising tail'' strategy. Peptide constructs of the form H-hydrophobic peptide-glycolamide ester-(Gly-Arg)(4)-Gly-OH were synthesised by Boc SPPS. The peptide-constructs

  20. Plasma from preeclamptic women activates endothelial cells via monocyte activation in vitro

    NARCIS (Netherlands)

    Faas, Marijke M.; van Pampus, Maria G.; Anninga, Zwanine A.; Salomons, Jet; Westra, Inge M.; Donker, Rogier B.; Aarnoudse, Jan G.; de Vos, Paul

    2010-01-01

    In this study we tested whether plasma from preeclamptic women contains factors that can activate endothelial cells in the presence of monocytes in vitro. Plasma from preeclamptic women (n = 6), healthy pregnant women (n = 6) and nonpregnant women (n = 6) was incubated with mono-cultures and co-cult

  1. Interferon-beta induces distinct gene expression response patterns in human monocytes versus T cells.

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    Noa Henig

    Full Text Available BACKGROUND: Monocytes, which are key players in innate immunity, are outnumbered by neutrophils and lymphocytes among peripheral white blood cells. The cytokine interferon-β (IFN-β is widely used as an immunomodulatory drug for multiple sclerosis and its functional pathways in peripheral blood mononuclear cells (PBMCs have been previously described. The aim of the present study was to identify novel, cell-specific IFN-β functions and pathways in tumor necrosis factor (TNF-α-activated monocytes that may have been missed in studies using PBMCs. METHODOLOGY/PRINCIPAL FINDINGS: Whole genome gene expression profiles of human monocytes and T cells were compared following in vitro priming to TNF-α and overnight exposure to IFN-β. Statistical analyses of the gene expression data revealed a cell-type-specific change of 699 transcripts, 667 monocyte-specific transcripts, 21 T cell-specific transcripts and 11 transcripts with either a difference in the response direction or a difference in the magnitude of response. RT-PCR revealed a set of differentially expressed genes (DEGs, exhibiting responses to IFN-β that are modulated by TNF-α in monocytes, such as RIPK2 and CD83, but not in T cells or PBMCs. Known IFN-β promoter response elements, such as ISRE, were enriched in T cell DEGs but not in monocyte DEGs. The overall directionality of the gene expression regulation by IFN-β was different in T cells and monocytes, with up-regulation more prevalent in T cells, and a similar extent of up and down-regulation recorded in monocytes. CONCLUSIONS: By focusing on the response of distinct cell types and by evaluating the combined effects of two cytokines with pro and anti-inflammatory activities, we were able to present two new findings First, new IFN-β response pathways and genes, some of which were monocytes specific; second, a cell-specific modulation of the IFN-β response transcriptome by TNF-α.

  2. Study of the Chemotactic Response of Multicellular Spheroids in a Microfluidic Device

    Science.gov (United States)

    Ayuso, Jose M.; Basheer, Haneen A.; Monge, Rosa; Sánchez-Álvarez, Pablo; Doblaré, Manuel; Shnyder, Steven D.; Vinader, Victoria; Afarinkia, Kamyar

    2015-01-01

    We report the first application of a microfluidic device to observe chemotactic migration in multicellular spheroids. A microfluidic device was designed comprising a central microchamber and two lateral channels through which reagents can be introduced. Multicellular spheroids were embedded in collagen and introduced to the microchamber. A gradient of fetal bovine serum (FBS) was established across the central chamber by addition of growth media containing serum into one of the lateral channels. We observe that spheroids of oral squamous carcinoma cells OSC–19 invade collectively in the direction of the gradient of FBS. This invasion is more directional and aggressive than that observed for individual cells in the same experimental setup. In contrast to spheroids of OSC–19, U87-MG multicellular spheroids migrate as individual cells. A study of the exposure of spheroids to the chemoattractant shows that the rate of diffusion into the spheroid is slow and thus, the chemoattractant wave engulfs the spheroid before diffusing through it. PMID:26444904

  3. PTEN functions to 'prioritize' chemotactic cues and prevent 'distraction' in migrating neutrophils.

    Science.gov (United States)

    Heit, Bryan; Robbins, Stephen M; Downey, Charlene M; Guan, Zhiwen; Colarusso, Pina; Miller, B Joan; Jirik, Frank R; Kubes, Paul

    2008-07-01

    Neutrophils encounter and 'prioritize' many chemoattractants in their pursuit of bacteria. Here we tested the possibility that the phosphatase PTEN is responsible for the prioritization of chemoattractants. Neutrophils induced chemotaxis by two separate pathways, the phosphatidylinositol-3-OH kinase (PI(3)K) phosphatase and tensin homolog (PTEN) pathway, and the p38 mitogen-activated protein kinase pathway, with the p38 pathway dominating over the PI(3)K pathway. Pten(-/-) neutrophils could not prioritize chemoattractants and were 'distracted' by chemokines when moving toward bacterial chemoattractants. In opposing gradients, PTEN became distributed throughout the cell circumference, which inhibited all PI(3)K activity, thus permitting 'preferential' migration toward bacterial products via phospholipase A(2) and p38. Such prioritization was defective in Pten(-/-) neutrophils, which resulted in defective bacterial clearance in vivo. Our data identify a PTEN-dependent mechanism in neutrophils to prioritize, 'triage' and integrate responses to multiple chemotactic cues.

  4. How many consumer levels can survive in a chemotactic food chain?

    Institute of Scientific and Technical Information of China (English)

    Jing LIU; Chunhua OU

    2009-01-01

    We investigate the effect and the impact of predator-prey interactions, diffusivity and chemotaxis on the ability of survival of multiple consumer levels in a predator-prey microbial food chain. We aim at answering the question of how many consumer levels can survive from a dynamical system point of view. To solve this standing issue on food-chain length, first we construct a chemotactic food chain model. A priori bounds of the steady state populations are obtained. Then under certain sufficient conditions combining the effect of conversion efficiency, diffusivity and chemotaxis parameters, we derive the co-survival of all consumer levels, thus obtaining the food chain length of our model. Numerical simulations not only confirm our theoretical results, but also demonstrate the impact of conversion efficiency, diffusivity and chemotaxis behavior on the survival and stability of various consumer levels.

  5. Translation of Pur-α is targeted by cellular miRNAs to modulate the differentiation-dependent susceptibility of monocytes to HIV-1 infection.

    Science.gov (United States)

    Shen, Chan-Juan; Jia, Yan-Hui; Tian, Ren-Rong; Ding, Ming; Zhang, Chiyu; Wang, Jian-Hua

    2012-11-01

    The postentry restriction of HIV-1 replication in monocytes can be relieved when they differentiate to dendritic cells (DCs) or macrophages. Multiple mechanisms have been proposed to interpret the differentiation-dependent susceptibility of monocytes to HIV-1 infection, and the absence of host-cell-encoded essential factors for HIV-1 completing the life cycle may provide an explanation. We have analyzed the gene expression profile in monocytes by mRNA microarray and compared it with that of differentiated DCs. We demonstrated that purine-rich element binding protein α (Pur-α), a host-cell-encoded ubiquitous, sequence-specific DNA- and RNA-binding protein, showed inadequate expression in monocytes, and the translation of Pur-α mRNA was repressed by cell-expressed microRNA (miRNA). These Pur-α-targeted miRNAs modulated the differentiation-dependent susceptibility of monocytes/DCs to HIV-1 infection, because rescue of Pur-α expression by transfection of miRNA inhibitors relieved the restriction of HIV-1 infection in monocytes, and ectopic input of miRNA mimics significantly reduced HIV-1 infection of monocyte-derived DCs (MDDCs). Collectively, our data emphasized that inadequate host factors contribute to HIV-1 restriction in monocytes, and cellular miRNAs modulate differentiation-dependent susceptibility of host cells to HIV-1 infection. Elaboration of HIV-1 restriction in host cells facilitates our understanding of viral pathogenesis and the search for a new antiviral strategy.

  6. Characterization of canine monocyte-derived dendritic cells with phenotypic and functional differentiation.

    Science.gov (United States)

    Wang, Yu-Shan; Chi, Kwan-Hwa; Liao, Kuang-Wen; Liu, Cheng-Chi; Cheng, Chiao-Lei; Lin, Yi-Chun; Cheng, Chiung-Hsiang; Chu, Rea-Min

    2007-07-01

    For therapeutic purposes, large numbers of dendritic cells (DCs) are essential. In this study, we used 2% autologous canine plasma, granulocyte/macrophage colony-stimulating factor (GM-CSF), fms-like tyrosine kinase 3 ligand (Flt3L), and interleukin 4 (IL-4) in generating monocyte-derived DCs from peripheral blood mononuclear cells of dogs. The plasma enriched the population of CD14-positive monocytes by greatly enhancing the efficiency of monocyte adherence, the proportion of adherent cells increasing from 6.6% with 10% fetal bovine serum to 15.3% with 2% autologous canine plasma. Culturing the adherent monocytes for 6 d with human GM-CSF, canine IL-4, and human Flt3L significantly increased the yield of DCs, more than 90% of which were CD14-negative. Because, in the presence of lipopolysaccharide (LPS), monocytes that were CD14-positive expressed tumor necrosis factor ac much more than DCs with low levels of CD14, it is important to decrease the numbers of CD14-positive cells in generating monocyte-derived DCs. With flow cytometry and real-time reverse-transcriptase-mediated polymerase chain reaction assays, we found that in canine immature DCs (iDCs) the expression of DLA class II molecules, CD1a, CD11c, CD40, and CD86 was high and the expression of CD80, CD83, and CD14 either low or negative. During maturation (stimulated by LPS), the expression of CDla, CD40, CD83, and CD80 was upregulated. However, the expression of DLA class II molecules, CD11c, and CD86 was not increased in mature DCs. Incubating the iDCs with LPS decreased antigen uptake and increased the cells' immunostimulatory capacity (assessed by the allogeneic mixed-lymphocyte reaction), indicating that LPS accelerates the functional maturation of DCs. This protocol may facilitate the use of DCs in cellular immunotherapy.

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

    Directory of Open Access Journals (Sweden)

    Henning W Zimmermann

    2012-10-01

    Full Text Available Different etiologies such as drug toxicity, acute viral hepatitis B or acetaminophen poisoning can cause acute liver injury (ALI or even acute liver failure (ALF. Excessive cell death of hepatocytes in the liver is known to result in a strong hepatic inflammation. Experimental murine models of liver injury highlighted the importance of hepatic macrophages, so-called Kupffer cells, for initiating and driving this inflammatory response by releasing proinflammatory cytokines and chemokines including tumor necrosis factor (TNF, interleukin-6 (IL-6, IL-1-beta or monocyte chemoattractant protein 1 (MCP-1, CCL2 as well as activating other non-parenchymal liver cells, e.g. endothelial or hepatic stellate cells (HSC. Many of these proinflammatory mediators can trigger hepatocytic cell death pathways, e.g. via caspase activation, but also activate protective signaling pathways, e.g. via nuclear factor kappa B (NF-kB. Recent studies in mice demonstrated that these macrophage actions largely depend on the recruitment of monocytes into the liver, namely of the inflammatory Ly6c+ (Gr1+ monocyte subset as precursors of tissue macrophages. The chemokine receptor CCR2 and its ligand MCP-1/CCL2 promote monocyte subset infiltration upon liver injury. In contrast, the chemokine receptor CX3CR1 and its ligand fractalkine (CX3CL1 are important negative regulators of monocyte infiltration by controlling their survival and differentiation into functionally diverse macrophage subsets upon injury. The recently identified cellular and molecular pathways for monocyte subset recruitment, macrophage differentiation and interactions with other hepatic cell types in the injured liver may therefore represent interesting novel targets for future therapeutic approaches in ALF.

  8. TNFα secretion of monocytes exposed to pulsed radiofrequency treatment: a possible working mechanism of PRF chronic pain management.

    Science.gov (United States)

    Maretto, Fabio; Vennik, Marco; Albers, Kim I; van Duijn, Bert

    2014-06-01

    Pulsed radiofrequency treatment (PRF) is a promising new technique increasingly used in treatment of chronic pain. The molecular working mechanism of PRF is not exactly known and is currently being investigated. This study investigates a possible role of PRF-induced modulation of TNFα secretion by differentiated monocytes in chronic pain management. The results show no significant PRF-induced change in TNFα secretion of lipopolysaccharides (LPS)-stimulated monocytes. However, PRF does significantly increase TNFα secretion of differentiated monocytes that have not been stimulated with LPS. This may indicate a possible role of PRF treatment in increasing TNFα production of nonstimulated monocytes. More research is needed to determine whether this is truly a part of the working mechanism of PRF in chronic pain management and which other factors are involved. © 2013 World Institute of Pain.

  9. Hydrogen sulfide suppresses oxidized low-density lipoprotein (ox-LDL)-stimulated monocyte chemoattractant protein 1 generation from macrophages via the nuclear factor κB (NF-κB) pathway.

    Science.gov (United States)

    Du, Junbao; Huang, Yaqian; Yan, Hui; Zhang, Qiaoli; Zhao, Manman; Zhu, Mingzhu; Liu, Jia; Chen, Stella X; Bu, Dingfang; Tang, Chaoshu; Jin, Hongfang

    2014-04-01

    This study was designed to examine the role of hydrogen sulfide (H2S) in the generation of oxidized low-density lipoprotein (ox-LDL)-stimulated monocyte chemoattractant protein 1 (MCP-1) from macrophages and possible mechanisms. THP-1 cells and RAW macrophages were pretreated with sodium hydrosulfide (NaHS) and hexyl acrylate and then treated with ox-LDL. The results showed that ox-LDL treatment down-regulated the H2S/cystathionine-β-synthase pathway, with increased MCP-1 protein and mRNA expression in both THP-1 cells and RAW macrophages. Hexyl acrylate promoted ox-LDL-induced inflammation, whereas the H2S donor NaHS inhibited it. NaHS markedly suppressed NF-κB p65 phosphorylation, nuclear translocation, DNA binding activity, and recruitment to the MCP-1 promoter in ox-LDL-treated macrophages. Furthermore, NaHS decreased the ratio of free thiol groups in p65, whereas the thiol reductant DTT reversed the inhibiting effect of H2S on the p65 DNA binding activity. Most importantly, site-specific mutation of cysteine 38 to serine in p65 abolished the effect of H2S on the sulfhydration of NF-κB and ox-LDL-induced NF-κB activation. These results suggested that endogenous H2S inhibited ox-LDL-induced macrophage inflammation by suppressing NF-κB p65 phosphorylation, nuclear translocation, DNA binding activity, and recruitment to the MCP-1 promoter. The sulfhydration of free thiol group on cysteine 38 in p65 served as a molecular mechanism by which H2S inhibited NF-κB pathway activation in ox-LDL-induced macrophage inflammation.

  10. Stochastic coordination of multiple actuators reduces latency and improves chemotactic response in bacteria.

    Science.gov (United States)

    Sneddon, Michael W; Pontius, William; Emonet, Thierry

    2012-01-17

    Individual neuronal, signal transduction, and regulatory pathways often control multiple stochastic downstream actuators, which raises the question of how coordinated response to a single input can be achieved when individual actuators fluctuate independently. In Escherichia coli, the bacterial chemotaxis pathway controls the activity of multiple flagellar motors to generate the run-and-tumble motion of the cell. High-resolution microscopy experiments have identified the key conformational changes adopted by individual flagella during this process. By incorporating these observations into a stochastic model of the flagellar bundle, we demonstrate that the presence of multiple motors imposes a trade-off on chemotactic performance. Multiple motors reduce the latency of the response below the time scale of the stochastic switching of a single motor, which improves performance on steep gradients of attractants. However, the uncoordinated switching of multiple motors interrupts and shortens cell runs, which thereby reduces signal detection and performance on shallow gradients. Remarkably, when slow fluctuations generated by the adaptation mechanism of the chemotaxis system are incorporated in the model at levels measured in experiments, the chemotactic sensitivity and performance in shallow gradients is partially restored with marginal effects for steep gradients. The noise is beneficial because it simultaneously generates long events in the statistics of individual motors and coordinates the motors to generate a long tail in the run length distribution of the cell. Occasional long runs are known to enhance exploration of random walkers. Here we show that they have the additional benefit of enhancing the sensitivity of the bacterium to very shallow gradients.

  11. Toluene-Degrading Bacteria Are Chemotactic towards the Environmental Pollutants Benzene, Toluene, and Trichloroethylene

    Science.gov (United States)

    Parales, Rebecca E.; Ditty, Jayna L.; Harwood, Caroline S.

    2000-01-01

    The bioremediation of polluted groundwater and toxic waste sites requires that bacteria come into close physical contact with pollutants. This can be accomplished by chemotaxis. Five motile strains of bacteria that use five different pathways to degrade toluene were tested for their ability to detect and swim towards this pollutant. Three of the five strains (Pseudomonas putida F1, Ralstonia pickettii PKO1, and Burkholderia cepacia G4) were attracted to toluene. In each case, the response was dependent on induction by growth with toluene. Pseudomonas mendocina KR1 and P. putida PaW15 did not show a convincing response. The chemotactic responses of P. putida F1 to a variety of toxic aromatic hydrocarbons and chlorinated aliphatic compounds were examined. Compounds that are growth substrates for P. putida F1, including benzene and ethylbenzene, were chemoattractants. P. putida F1 was also attracted to trichloroethylene (TCE), which is not a growth substrate but is dechlorinated and detoxified by P. putida F1. Mutant strains of P. putida F1 that do not oxidize toluene were attracted to toluene, indicating that toluene itself and not a metabolite was the compound detected. The two-component response regulator pair TodS and TodT, which control expression of the toluene degradation genes in P. putida F1, were required for the response. This demonstration that soil bacteria can sense and swim towards the toxic compounds toluene, benzene, TCE, and related chemicals suggests that the introduction of chemotactic bacteria into selected polluted sites may accelerate bioremediation processes. PMID:10966434

  12. The role of eicosanoids in the chemotactic response to Pasteurella haemolytica infection.

    Science.gov (United States)

    Clarke, C R; Lauer, A K; Barron, S J; Wyckoff, J H

    1994-10-01

    The chemotactic role of eicosanoids in the pathogenesis of Pasteurella haemolytica infection was studied, using a tissue chamber infection model and pharmacological inhibitors of eicosanoid synthesis. Tissue chambers were implanted subcutaneously in 12 calves allotted to three treatment groups of equal size. At 45 days after implantation, calves received saline, dexamethasone, or phenylbutazone treatments, and tissue chambers in all animals were then inoculated with P. haemolytica. Chamber fluid samples were collected before inoculation and at 2, 6, 18, 40, and 90 h after inoculation. Bacterial counts, total leukocyte counts, pH and albumin concentrations in chamber fluids were determined using standard bacteriological and clinical pathological methods. Concentrations of eicosanoids and activity of interleukin-1 (IL-1) were measured by radioimmunoassay and a helper T cell bioassay, respectively. Concentrations of leukotriene B4 (LTB4), thromboxane B2 (TXB2), 6-keto-prostaglandin F1 alpha (PGF1 alpha) and prostaglandin E2 (PGE2) increased markedly after inoculation. An inhibitory effect of dexamethasone on both LTB4 production and neutrophil influx, together with the temporal relationship between these two events, suggested that LTB4 served as a chemo-attractant. Activity-time profiles for IL-1 in chamber fluids were similar to those of the eicosanoids. Phenylbutazone and dexamethasone reduced the severity of the inflammatory responses as measured by lower concentrations of albumin and higher pH in treated versus control chamber fluids. The results of this study suggest that eicosanoid inflammatory mediators play an important chemotactic role in the pathogenesis of P. haemolytica infection.

  13. Effect of Serum and Oxygen Concentration on Gene Expression and Secretion of Paracrine Factors by Mesenchymal Stem Cells

    Directory of Open Access Journals (Sweden)

    Patrick Page

    2014-01-01

    Full Text Available Mesenchymal stem cells (MSC secrete paracrine factors that may exert a protective effect on the heart after coronary artery occlusion. This study was done to determine the effect of hypoxia and serum levels on the mRNA expression and secretion of paracrine factors. Mouse bone marrow MSC were cultured with 5% or 20% serum and in either normoxic (21% O2 or hypoxic (1% O2 conditions. Expression of mRNA for vascular endothelial growth factor (VEGF, monocyte chemotactic protein-1 (MCP-1, macrophage inflammatory protein-1α (MIP-1α, MIP-1β, and matrix metalloproteinase-2 (MMP-2 was determined by RT-qPCR. Secretion into the culture media was determined by ELISA. Hypoxia caused a reduction in gene expression for MCP-1 and an increase for VEGF (5% serum, MIP-1α, MIP-1β, and MMP-2. Serum reduction lowered gene expression for VEGF (normoxia, MCP-1 (hypoxia, MIP-1α (hypoxia, MIP-1β (hypoxia, and MMP-2 (hypoxia and increased gene expression for MMP-2 (normoxia. The level of secretion of these factors into the media generally paralleled gene expression with some exceptions. These data demonstrate that serum and oxygen levels have a significant effect on the gene expression and secretion of paracrine factors by MSC which will affect how MSC interact in vivo during myocardial ischemia.

  14. Monocyte-platelet interaction induces a pro-inflammatory phenotype in circulating monocytes.

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    Gabriella Passacquale

    Full Text Available BACKGROUND: Activated platelets exert a pro-inflammatory action that can be largely ascribed to their ability to interact with leukocytes and modulate their activity. We hypothesized that platelet activation and consequent formation of monocyte-platelet aggregates (MPA induces a pro-inflammatory phenotype in circulating monocytes. METHODOLOGY/PRINCIPAL FINDINGS: CD62P(+ platelets and MPA were measured, and monocytes characterized, by whole blood flow cytometry in healthy subjects, before and two days after receiving influenza immunization. Three monocytic subsets were identified: CD14(+CD16(-, CD14(highCD16(+and CD14(lowCD16(+. The increase in high sensitivity C-reactive protein post-immunization was accompanied by increased platelet activation and MPA formation (25.02±12.57 vs 41.48±16.81; p = 0.01, along with enhancement of circulating CD14(highCD16(+ cells (4.7±3.6 vs 10.4±4.8; p = 0.003, their percentage being linearly related to levels of CD62P(+-platelets (r(2 = 0.4347; p = 0.0008. In separate in vitro experiments, co-incubation of CD14(+CD16(- cells, isolated from healthy donor subjects, with autologous platelets gave rise to up-regulation of CD16 on monocytes as compared with those maintained in medium alone (% change in CD14(+CD16(+ cells following 48 h co-incubation of monocytes with platelets was +106±51% vs monocytes in medium alone; p<0.001. This effect correlated directly with degree of MPA formation (r(2 = 0.7731; p<0.0001 and was associated with increased monocyte adhesion to endothelial cells. P-selectin glycoprotein ligand-1 (PSGL-1 blocking antibody, which abrogates MPA formation, abolished these effects, as did the cyclooxygenase (COX-2 selective inhibitor NS-398, aspirin and the EP1/EP2-selective antagonist AH6809. CONCLUSIONS/SIGNIFICANCE: These data suggest that MPA formation, as occurs in the blood under pro-inflammatory conditions, expands the pool of circulating CD14(highCD16(+ monocytes in a

  15. Divergent effect of cobalt and beryllium salts on the fate of peripheral blood monocytes and T lymphocytes.

    Science.gov (United States)

    Paladini, Fabiana; Cocco, Elisa; Potolicchio, Ilaria; Fazekasova, Henrieta; Lombardi, Giovanna; Fiorillo, Maria Teresa; Sorrentino, Rosa

    2011-02-01

    Occupational exposure to metals such as cobalt and beryllium represents a risk factor for respiratory health and can cause immune-mediated diseases. However, the way they act may be different. We show here that the two metals have a divergent effect on peripheral T lymphocytes and monocytes: BeSO(4) induces cell death in monocytes but not in T lymphocytes, which instead respond by producing Interferon gamma (IFN-γ); conversely, CoCl(2) induces apoptosis in T lymphocytes but not in monocytes. Interestingly, both metals induce p53 overexpression but with a dramatic different outcome. This is because the effect of p53 in CoCl(2)-treated monocytes is counteracted by the antiapoptotic activity of cytoplasmic p21(Cip1/WAF1), the activation of nuclear factor κB, and the inflammasome danger signaling pathway leading to the production of proinflammatory cytokines. However, CoCl(2)-treated monocytes do not fully differentiate into macrophage or dendritic cells, as inferred by the lack of expression of CD16 and CD83, respectively. Furthermore, the expression of HLA-class II molecules, as well as the capability of capturing and presenting the antigens, decreased with time. In conclusion, cobalt keeps monocytes in a partially activated, proinflammatory state that can contribute to some of the pathologies associated with the exposure to this metal.

  16. CKbeta-8 [CCL23], a novel CC chemokine, is chemotactic for human osteoclast precursors and is expressed in bone tissues.

    Science.gov (United States)

    Votta, B J; White, J R; Dodds, R A; James, I E; Connor, J R; Lee-Rykaczewski, E; Eichman, C F; Kumar, S; Lark, M W; Gowen, M

    2000-05-01

    We have previously demonstrated that a tartrate-resistant acid phosphatase (TRAP)-positive subpopulation of mononuclear cells isolated from collagenase digests of human osteoclastoma tissue exhibits an osteoclast phenotype and can be induced to resorb bone. Using these osteoclast precursors as a model system, we have assessed the chemotactic potential of 16 chemokines. Three CC chemokines, the recently described CKbeta-8, RANTES, and MIP-1alpha elicited significant chemotactic responses. In contrast, 10 other CC chemokines (MIP-1beta, MCP-1, MCP-2, MCP-3, MCP-4, HCC-1, eotaxin-2, PARC, SLC, ELC) and 3 CXC chemokines (IL-8, GROalpha, SDF-1) were inactive. None of these chemokines showed any chemotactic activity for either primary osteoblasts derived from human bone explants or the osteoblastic MG-63 cell line. The identity of the osteoclast receptor that mediates the chemotactic response remains to be established. However, all three active chemokines have been reported to bind to CCR1 and cross-desensitization studies demonstrate that RANTES and MIP-1alpha can partially inhibit the chemotactic response elicited by CKbeta-8. CKbeta-8, the most potent of the active CC chemokines (EC(max) 0.1-0.3 nM), was further characterized with regard to expression in human bone and cartilage. Although expression is not restricted to these tissues, CKbeta-8 mRNA was shown to be highly expressed in osteoblasts and chondrocytes in human fetal bone by in situ hybridization. In addition, CKbeta-8 protein was shown to be present in human osteophytic tissue by immunolocalization. These observations suggest that CKbeta-8, and perhaps other chemokines, may play a role in the recruitment of osteoclast precursors to sites of bone resorption.

  17. Patrolling Monocytes Control Tumor Metastasis to the Lung

    Science.gov (United States)

    Hanna, Richard N.; Cekic, Caglar; Sag, Duygu; Tacke, Robert; Thomas, Graham D.; Nowyhed, Heba; Herrley, Erica; Rasquinha, Nicole; McArdle, Sara; Wu, Runpei; Peluso, Esther; Metzger, Daniel; Ichinose, Hiroshi; Shaked, Iftach; Chodaczek, Grzegorz; Biswas, Subhra K.; Hedrick, Catherine C.

    2016-01-01

    The immune system plays an important role in regulating tumor growth and metastasis. For example, classical monocytes promote tumorigenesis and cancer metastasis; however, how nonclassical “patrolling” monocytes interact with tumors is unknown. Here we show that patrolling monocytes are enriched in the microvasculature of the lung and reduce tumor metastasis to lung in multiple mouse metastatic tumor models. Nr4a1-deficient mice, which specifically lack patrolling monocytes, showed increased lung metastasis in vivo. Transfer of Nr4a1-proficient patrolling monocytes into Nr4a1-deficient mice prevented tumor invasion in lung. Patrolling monocytes established early interactions with metastasizing tumor cells, scavenged tumor material from the lung vasculature and promoted natural killer cell recruitment and activation. Thus, patrolling monocytes contribute to cancer immunosurveillance and may be targets for cancer immunotherapy. PMID:26494174

  18. Clinical history and hematological findings among canines with monocytic ehrlichiosis.

    Science.gov (United States)

    Moonarmart, Walasinee; Sungpradit, Sivapong; Rawangchue, Thanakorn; Suphaphiphat, Karuna; Suksusieng, Sineenart; Jirapattharasate, Charoonluk

    2014-01-01

    Canine monocytic ehrlichiosis is a tick borne disease caused by Ehrlichia canis, an obligate intracellular rickettsial organism belonging to the family Anaplasmataceae. Canine ehrlichiosis causes hemaotological changes among infected animals which could be used as a potential predictor for diagnosing canine monocytic ehrlichiosis (CME). Ninety-four blood samples were obtained from canines that either presented for a routine health check-up or for clinical illness. A history, physical and laboratory test were conducted on each animal. All samples were examined for E. canis using a 16S rDNA polymerase chain reaction (PCR) amplification to confirm CME infection. Thirty-six of the samples were positive for E. canis using PCR and the rest were negative. The Mann-Whitney and chi-square test were used to compare the differences between the PCR-positive and negative animals. PCR-positive animals had a higher mean body temperature than PCR-negative animals. The following were significantly lower in PCR-positive animals: white blood cell count, eosinophil count, red blood cell count, hemoglobin, hematocrit, platelet count, and the random distribution of width (RDW) of the red blood cells. We evaluated complete blood cell count findings to determine factors associated with CME using multivariable logistic regression analysis and found thrombocytopenia was significantly associated with CME (OR = 0.085; 95% CI: 0.78-0.92, p < 0.001). For every decrease in the platelet count of 10,000 there was a 15% increase in the likelihood of having CME.

  19. [Neutrophils and monocytes in gingival epithelium

    Science.gov (United States)

    Meng, H X; Zheng, L P

    1994-06-01

    Neutrophils and monocytes of gingival epithellium in health gingiva(H),marginal gingivitis(MG),juvenile periodontitis(JP),adult periodontitis(AP) and subgingival bacteria were quantitated and analyzed,The results showed that the numbers of PMN within either pocket epithelium or oral gingival epithelium in JP were significantly lower than in AP and G.The amounts of PMN in AP were much larger than other three groups.Positive correlation between the number of PMN in sulcular pocket epitelium and the motile bacteri of subgingival plaque was demonstrated by correlation analysis.Monocytes mainly presented in deep pocket and junctional epithelum which were stained by NAE method,however very few Langhans cells were seen in these areas.

  20. Induction of ceruloplasmin synthesis by IFN-gamma in human monocytic cells

    Science.gov (United States)

    Mazumder, B.; Mukhopadhyay, C. K.; Prok, A.; Cathcart, M. K.; Fox, P. L.

    1997-01-01

    Ceruloplasmin is a 132-kDa glycoprotein abundant in human plasma. It has multiple in vitro activities, including copper transport, lipid pro- and antioxidant activity, and oxidation of ferrous ion and aromatic amines; however, its physiologic role is uncertain. Although ceruloplasmin is synthesized primarily by the liver in adult humans, production by cells of monocytic origin has been reported. We here show that IFN-gamma is a potent inducer of ceruloplasmin synthesis by monocytic cells. Activation of human monoblastic leukemia U937 cells with IFN-gamma increased the production of ceruloplasmin by at least 20-fold. The identity of the protein was confirmed by plasmin fingerprinting. IFN-gamma also increased ceruloplasmin mRNA. Induction followed a 2- to 4-h lag and was partially blocked by cycloheximide, indicating a requirement for newly synthesized factors. Ceruloplasmin induction in monocytic cells was agonist specific, as IL-1, IL-4, IL-6, IFN-alpha, IFN-beta, TNF-alpha, and LPS were completely ineffective. The induction was also cell type specific, as IFN-gamma did not induce ceruloplasmin synthesis in endothelial or smooth muscle cells. In contrast, IFN-gamma was stimulatory in other monocytic cells, including THP-1 cells and human peripheral blood monocytes, and also in HepG2 cells. Ceruloplasmin secreted by IFN-gamma-stimulated U937 cells had ferroxidase activity and was, in fact, the only secreted protein with this activity. Monocytic cell-derived ceruloplasmin may contribute to defense responses via its ferroxidase activity, which may drive iron homeostasis in a direction unfavorable to invasive organisms.

  1. Monocyte to macrophage differentiation goes along with modulation of the plasmalogen pattern through transcriptional regulation.

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    Stefan Wallner

    Full Text Available BACKGROUND: Dysregulation of monocyte-macrophage differentiation is a hallmark of vascular and metabolic diseases and associated with persistent low grade inflammation. Plasmalogens represent ether lipids that play a role in diabesity and previous data show diminished plasmalogen levels in obese subjects. We therefore analyzed transcriptomic and lipidomic changes during monocyte-macrophage differentiation in vitro using a bioinformatic approach. METHODS: Elutriated monocytes from 13 healthy donors were differentiated in vitro to macrophages using rhM-CSF under serum-free conditions. Samples were taken on days 0, 1, 4 and 5 and analyzed for their lipidomic and transcriptomic profiles. RESULTS: Gene expression analysis showed strong regulation of lipidome-related transcripts. Enzymes involved in fatty acid desaturation and elongation were increasingly expressed, peroxisomal and ER stress related genes were induced. Total plasmalogen levels remained unchanged, while the PE plasmalogen species pattern became more similar to circulating granulocytes, showing decreases in PUFA and increases in MUFA. A partial least squares discriminant analysis (PLS/DA revealed that PE plasmalogens discriminate the stage of monocyte-derived macrophage differentiation. Partial correlation analysis could predict novel potential key nodes including DOCK1, PDK4, GNPTAB and FAM126A that might be involved in regulating lipid and especially plasmalogen homeostasis during differentiation. An in silico transcription analysis of lipid related regulation revealed known motifs such as PPAR-gamma and KLF4 as well as novel candidates such as NFY, RNF96 and Zinc-finger proteins. CONCLUSION: Monocyte to macrophage differentiation goes along with profound changes in the lipid-related transcriptome. This leads to an induction of fatty-acid desaturation and elongation. In their PE-plasmalogen profile macrophages become more similar to granulocytes than monocytes, indicating terminal

  2. Abnormalities in Monocyte Recruitment and Cytokine Expression in Monocyte Chemoattractant Protein 1–deficient Mice

    Science.gov (United States)

    Lu, Bao; Rutledge, Barbara J.; Gu, Long; Fiorillo, Joseph; Lukacs, Nicholas W.; Kunkel, Steven L.; North, Robert; Gerard, Craig; Rollins, Barrett J.

    1998-01-01

    Monocyte chemoattractant protein 1 (MCP-1) is a CC chemokine that attracts monocytes, memory T lymphocytes, and natural killer cells. Because other chemokines have similar target cell specificities and because CCR2, a cloned MCP-1 receptor, binds other ligands, it has been uncertain whether MCP-1 plays a unique role in recruiting mononuclear cells in vivo. To address this question, we disrupted SCYA2 (the gene encoding MCP-1) and tested MCP-1–deficient mice in models of inflammation. Despite normal numbers of circulating leukocytes and resident macrophages, MCP-1−/− mice were specifically unable to recruit monocytes 72 h after intraperitoneal thioglycollate administration. Similarly, accumulation of F4/80+ monocytes in delayed-type hypersensitivity lesions was impaired, although the swelling response was normal. Development of secondary pulmonary granulomata in response to Schistosoma mansoni eggs was blunted in MCP-1−/− mice, as was expression of IL-4, IL-5, and interferon γ in splenocytes. In contrast, MCP-1−/− mice were indistinguishable from wild-type mice in their ability to clear Mycobacterium tuberculosis. Our data indicate that MCP-1 is uniquely essential for monocyte recruitment in several inflammatory models in vivo and influences expression of cytokines related to T helper responses. PMID:9463410

  3. Statins attenuate polymethylmethacrylate-mediated monocyte activation.

    LENUS (Irish Health Repository)

    Laing, Alan J

    2012-02-03

    BACKGROUND: Periprosthetic osteolysis precipitates aseptic loosening of components, increases the risk of periprosthetic fracture and, through massive bone loss, complicates revision surgery and ultimately is the primary cause for failure of joint arthroplasty. The anti-inflammatory properties of HMG-CoA reductase inhibitors belonging to the statin family are well recognized. We investigated a possible role for status in initiating the first stage of the osteolytic cycle, namely monocytic activation. METHODS: We used an in vitro model of the human monocyte\\/macrophage inflammatory response to poly-methylmethacrylate (PMMA) particles after pretreat-ing cells with cerivastatin, a potent member of the statin family. Cell activation based upon production of TNF-alpha and MCP-1 cytokines was analyzed and the intracellular Raf-MEK-ERK signal transduction pathway was evaluated using western blot analysis, to identify its role in cell activation and in any cerivastatin effects observed. RESULTS: We found that pretreatment with cerivastatin significantly abrogates the production of inflammatory cytokines TNF-alpha and MCP-1 by human monocytes in response to polymethylmethacrylate particle activation. This inflammatory activation and attenuation appear to be mediated through the intracellular Raf-MEK-ERK pathway. INTERPRETATION: We propose that by intervening at the upstream activation stage, subsequent osteoclast activation and osteolysis can be suppressed. We believe that the anti-inflammatory properties of statins may potentially play a prophylactic role in the setting of aseptic loosening, and in so doing increase implant longevity.

  4. EXPRESSION OF ADHESION MOLECULES ON PERIPHERAL BLOOD MONOCYTES DURING PREGNANCY

    Directory of Open Access Journals (Sweden)

    V. A. Mikhaylova

    2010-01-01

    Full Text Available Peripheral blood monocytes play a key role in regulation of immune response during pregnancy. Intensive adhesion of monocytes to endothelium proves that monocytes are activated during pregnancy. To determine a potential role of adhesion molecules for ability of monocytes to adhere, we studied expression of CD11a, CD11b, CD11c, CD18, CD49d, CD29 markers of monocytes from non-pregnant and pregnant women. Expression of adhesion molecules on monocytes was analyzed by flow cytometry. The amounts of CD11b-expressing monocytes increased during pregnancy, as compared with non-pregnant women. Intensity of CD11a, CD11b, CD11c, CD29 expression on the monocytes did also increase at normal pregnancy. These results suggest that intense adhesion of monocytes to endothelium during uncomplicated pregnancy may be determined by increased expression of CD11a, CD11b, CD11c, CD29, and higher amounts of CD11b+ monocytes.

  5. Enhancement of proinflammatory and procoagulant responses to silica particles by monocyte-endothelial cell interactions

    Directory of Open Access Journals (Sweden)

    Liu Xin

    2012-09-01

    Full Text Available Abstract Background Inorganic particles, such as drug carriers or contrast agents, are often introduced into the vascular system. Many key components of the in vivo vascular environment include monocyte-endothelial cell interactions, which are important in the initiation of cardiovascular disease. To better understand the effect of particles on vascular function, the present study explored the direct biological effects of particles on human umbilical vein endothelial cells (HUVECs and monocytes (THP-1 cells. In addition, the integrated effects and possible mechanism of particle-mediated monocyte-endothelial cell interactions were investigated using a coculture model of HUVECs and THP-1 cells. Fe3O4 and SiO2 particles were chosen as the test materials in the present study. Results The cell viability data from an MTS assay showed that exposure to Fe3O4 or SiO2 particles at concentrations of 200 μg/mL and above significantly decreased the cell viability of HUVECs, but no significant loss in viability was observed in the THP-1 cells. TEM images indicated that with the accumulation of SiO2 particles in the cells, the size, structure and morphology of the lysosomes significantly changed in HUVECs, whereas the lysosomes of THP-1 cells were not altered. Our results showed that reactive oxygen species (ROS generation; the production of interleukin (IL-6, IL-8, monocyte chemoattractant protein 1 (MCP-1, tumor necrosis factor (TNF-α and IL-1β; and the expression of CD106, CD62E and tissue factor in HUVECs and monocytes were significantly enhanced to a greater degree in the SiO2-particle-activated cocultures compared with the individual cell types alone. In contrast, exposure to Fe3O4 particles had no impact on the activation of monocytes or endothelial cells in monoculture or coculture. Moreover, using treatment with the supernatants of SiO2-particle-stimulated monocytes or HUVECs, we found that the enhancement of proinflammatory response by SiO2

  6. The Effect of Bone Marrow Mesenchymal Stem Cells on Vitamin D3 Induced Monocytic Differentiation of U937 Cells

    Science.gov (United States)

    Molaeipour, Zahra; Shamsasanjan, Karim; Movassaghpour, Ali Akbari; Akbarzadehlaleh, Parvin; Sabaghi, Fatemeh; Saleh, Mahshid

    2016-01-01

    Purpose: Mesenchymal stem cells (MSCs) are key components of the hematopoietic stem cells (HSCs) niche. They control the process of hematopoiesis by secreting regulatory cytokines, growth factors and expression of important cell adhesion molecules for cell-tocell interactions. In this research, we have investigated the effect of bone marrow derived MSCs on monocytic differentiation of U937 cells line. Methods: U937 cells were cultured in both direct co-culture with MSCs and MSCs conditioned medium (C.M) driven. This study used 1,25-dihydroxyvitamin D3(VitD3) as inductor of monocytic differentiation and U937 cells treated with VitD3 morphology was examined by Wright Giemsa staining. CD14 monocytic differentiation marker was measured by flow cytometry and monocytic gene expression was assessed by real time polymerase chain reaction (RT PCR). Results: The results of flow cytometric analysis showed that CD14 expression of U937 increased. The higher effect of MSCs co-culture on CD14 expression in U937 cells was observed, compared to the conditioned medium. Among ten monocytic related genes which were screened that was observed increase in 5 genes in which CXCR4 and CSF2RA showed significant increase. Conclusion: The results obtained show that MSCs have supportive effect on the monocytic differentiation of U937 cells. However, a distinct mechanism of that remains unclear. PMID:27123414

  7. Toxoplasma gondii profilin promotes recruitment of Ly6Chi CCR2+ inflammatory monocytes that can confer resistance to bacterial infection.

    Directory of Open Access Journals (Sweden)

    Lori M Neal

    2014-06-01

    Full Text Available Ly6C+ inflammatory monocytes are essential to host defense against Toxoplasma gondii, Listeria monocytogenes and other infections. During T. gondii infection impaired inflammatory monocyte emigration results in severe inflammation and failure to control parasite replication. However, the T. gondii factors that elicit these monocytes are unknown. Early studies from the Remington laboratory showed that mice with a chronic T. gondii infection survive lethal co-infections with unrelated pathogens, including L. monocytogenes, but a mechanistic analysis was not performed. Here we report that this enhanced survival against L. monocytogenes is due to early reduction of bacterial burdens and elicitation of Ly6C+ inflammatory monocytes. We demonstrate that a single TLR11/TLR12 ligand profilin (TgPRF was sufficient to reduce bacterial burdens similar to T. gondii chronic infection. Stimulation with TgPRF was also sufficient to enhance animal survival when administered either pre- or post-Listeria infection. The ability of TgPRF to reduce L. monocytogenes burdens was dependent on TLR11 and required IFN-γ but was not dependent on IL-12 signaling. TgPRF induced rapid production of MCP-1 and resulted in trafficking of Ly6Chi CCR2+ inflammatory monocytes and Ly6G+ neutrophils into the blood and spleen. Stimulation with TgPRF reduced L. monocytogenes burdens in mice depleted with the Ly6G specific MAb 1A8, but not in Ly6C/Ly6G specific RB6-8C5 depleted or CCR2-/- mice, indicating that only inflammatory monocytes are required for TgPRF-induced reduction in bacterial burdens. These results demonstrate that stimulation of TLR11 by TgPRF is a mechanism to promote the emigration of Ly6Chi CCR2+ monocytes, and that TgPRF recruited inflammatory monocytes can provide an immunological benefit against an unrelated pathogen.

  8. Inflammatory gene expression in monocytes of patients with schizophrenia : overlap and difference with bipolar disorder. A study in naturalistically treated patients

    NARCIS (Netherlands)

    Drexhage, Roosmarijn C.; van der Heul-Nieuwenhuijsen, Leonie; Padmos, Roos C.; van Beveren, Nico; Cohen, Dan; Versnel, Marjan A.; Nolen, Willem A.; Drexhage, Hemmo A.

    2010-01-01

    Accumulating evidence indicates an activated inflammatory response system as a vulnerability factor for schizophrenia (SZ) and bipolar disorder (BD). We aimed to detect a specific inflammatory monocyte gene expression signature in SZ and compare such signature with our recently described

  9. Comparison of techniques for the detection of monocyte specific antigens.

    Science.gov (United States)

    Jager, M J; Thompson, J S; Claas, F H; Van Rood, J J

    1985-10-10

    Monocyte specific antigens are relevant in renal and bone marrow transplantation, but a reproducible monocyte-antigen system has not yet been recognized. In order to establish a sensitive test system with reproducible results in monocyte serology, 3 different monocyte cytotoxicity techniques were compared. In our hands the two-colour fluorescence test on post-Ficoll total leukocyte suspensions fulfilled the criteria. This technique was used to screen sera from multiparous women and renal transplant recipients for the presence of monocyte specific antibodies. By testing sera on cells from individuals who were HLA compatible with the serum donors, anti-HLA reactions were excluded. Several promising sera containing monocyte specific antibodies were identified, thus indicating the success of our approach.

  10. Chemokinetic factors obtained from the larval stage of the cestode, Taenia taeniaeformis.

    Science.gov (United States)

    Camp, C J; Leid, R W

    1982-09-01

    Saline extracts of the metacestodes of Taenia taeniaeformis were shown to have chemokinetic as well as chemotactic activity for equine polymorphonuclear leucocytes. Although parasite derived chemotactic activity could be appreciated at high protein inputs, such leucotactic activity was quickly lost upon dilution. In contrast chemokinetic activity was readily observed in saline extracts over a much broader range of protein inputs. Utilizing the Zigmond-Hirsch checkerboard assay the chemokinetic properties in the saline extracts were more pronounced when chemokinetic factors were loaded into the cell compartment of the chemotactic chambers only. Mild heat treatment or storage at 4 degrees C resulted in little destruction of the chemokinetic factors. However six cycles of rapid freezing and thawing generated marked increases in chemokinetic activity and not chemotactic activity. The results of this work provide for the first time evidence of parasite derived chemokinetic factors.

  11. An adipoinductive role of inflammation in adipose tissue engineering: key factors in the early development of engineered soft tissues.

    Science.gov (United States)

    Lilja, Heidi E; Morrison, Wayne A; Han, Xiao-Lian; Palmer, Jason; Taylor, Caroline; Tee, Richard; Möller, Andreas; Thompson, Erik W; Abberton, Keren M

    2013-05-15

    Tissue engineering and cell implantation therapies are gaining popularity because of their potential to repair and regenerate tissues and organs. To investigate the role of inflammatory cytokines in new tissue development in engineered tissues, we have characterized the nature and timing of cell populations forming new adipose tissue in a mouse tissue engineering chamber (TEC) and characterized the gene and protein expression of cytokines in the newly developing tissues. EGFP-labeled bone marrow transplant mice and MacGreen mice were implanted with TEC for periods ranging from 0.5 days to 6 weeks. Tissues were collected at various time points and assessed for cytokine expression through ELISA and mRNA analysis or labeled for specific cell populations in the TEC. Macrophage-derived factors, such as monocyte chemotactic protein-1 (MCP-1), appear to induce adipogenesis by recruiting macrophages and bone marrow-derived precursor cells to the TEC at early time points, with a second wave of nonbone marrow-derived progenitors. Gene expression analysis suggests that TNFα, LCN-2, and Interleukin 1β are important in early stages of neo-adipogenesis. Increasing platelet-derived growth factor and vascular endothelial cell growth factor expression at early time points correlates with preadipocyte proliferation and induction of angiogenesis. This study provides new information about key elements that are involved in early development of new adipose tissue.

  12. Role of neoplastic monocyte-derived fibrocytes in primary myelofibrosis

    Science.gov (United States)

    Bueso-Ramos, Carlos E.; Newberry, Kate J.; Knez, Liza; Post, Sean M.; Ahn, Jihae; Levine, Ross L.; Kantarjian, Hagop M.

    2016-01-01

    Primary myelofibrosis (PMF) is a fatal neoplastic disease characterized by clonal myeloproliferation and progressive bone marrow (BM) fibrosis thought to be induced by mesenchymal stromal cells stimulated by overproduced growth factors. However, tissue fibrosis in other diseases is associated with monocyte-derived fibrocytes. Therefore, we sought to determine whether fibrocytes play a role in the induction of BM fibrosis in PMF. In this study, we show that BM from patients with PMF harbors an abundance of clonal, neoplastic collagen- and fibronectin-producing fibrocytes. Immunodeficient mice transplanted with myelofibrosis patients’ BM cells developed a lethal myelofibrosis-like phenotype. Treatment of the xenograft mice with the fibrocyte inhibitor serum amyloid P (SAP; pentraxin-2) significantly prolonged survival and slowed the development of BM fibrosis. Collectively, our data suggest that neoplastic fibrocytes contribute to the induction of BM fibrosis in PMF, and inhibiting fibrocyte differentiation with SAP may interfere with this process. PMID:27481130

  13. Modification of β-Defensin-2 by Dicarbonyls Methylglyoxal and Glyoxal Inhibits Antibacterial and Chemotactic Function In Vitro.

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    Janna G Kiselar

    Full Text Available Beta-defensins (hBDs provide antimicrobial and chemotactic defense against bacterial, viral and fungal infections. Human β-defensin-2 (hBD-2 acts against gram-negative bacteria and chemoattracts immature dendritic cells, thus regulating innate and adaptive immunity. Immunosuppression due to hyperglycemia underlies chronic infection in Type 2 diabetes. Hyperglycemia also elevates production of dicarbonyls methylgloxal (MGO and glyoxal (GO.The effect of dicarbonyl on defensin peptide structure was tested by exposing recombinant hBD-2 (rhBD-2 to MGO or GO with subsequent analysis by MALDI-TOF MS and LC/MS/MS. Antimicrobial function of untreated rhBD-2 vs. rhBD-2 exposed to dicarbonyl against strains of both gram-negative and gram-positive bacteria in culture was determined by radial diffusion assay. The effect of dicarbonyl on rhBD-2 chemotactic function was determined by chemotaxis assay in CEM-SS cells.MGO or GO in vitro irreversibly adducts to the rhBD-2 peptide, and significantly reduces antimicrobial and chemotactic functions. Adducts derive from two arginine residues, Arg22 and Arg23 near the C-terminus, and the N-terminal glycine (Gly1. We show by radial diffusion testing on gram-negative E. coli and P. aeruginosa, and gram-positive S. aureus, and a chemotaxis assay for CEM-SS cells, that antimicrobial activity and chemotactic function of rhBD-2 are significantly reduced by MGO.Dicarbonyl modification of cationic antimicrobial peptides represents a potential link between hyperglycemia and the clinical manifestation of increased susceptibility to infection, protracted wound healing, and chronic inflammation in undiagnosed and uncontrolled Type 2 diabetes.

  14. Chemotactic systems in the presence of conflicts: A new functional inequality

    Science.gov (United States)

    Wolansky, G.

    2016-11-01

    The evolution of a chemotactic system involving a population of cells attracted to self-produced chemicals is described by the Keller-Segel system. In dimension 2, this system demonstrates a balance between the spreading effect of diffusion and the concentration due to self-attraction. As a result, there exists a critical "mass" (i.e. total cell's population) above which the solution of this system collapses in a finite time, while below this critical mass there is global existence in time. In particular, subcritical mass leads under certain additional conditions to the existence of steady states, corresponding to the solution of an elliptic Liouville equation. The existence of this critical mass is related to a functional inequality known as the Moser-Trudinger inequality. An extension of the Keller-Segel model to several cells populations was considered before in the literature. Here we review some of these results and, in particular, consider the case of conflict between two populations, that is, when population one attracts population two, while, at the same time, population two repels population one. This assumption leads to a new functional inequality which generalizes the Moser-Trudinger inequality. As an application of this inequality we derive sufficient conditions for the existence of steady states corresponding to solutions of an elliptic Liouville system.

  15. A Worldwide Competition to Compare the Speed and Chemotactic Accuracy of Neutrophil-Like Cells.

    Directory of Open Access Journals (Sweden)

    Monica Skoge

    Full Text Available Chemotaxis is the ability to migrate towards the source of chemical gradients. It underlies the ability of neutrophils and other immune cells to hone in on their targets and defend against invading pathogens. Given the importance of neutrophil migration to health and disease, it is crucial to understand the basic mechanisms controlling chemotaxis so that strategies can be developed to modulate cell migration in clinical settings. Because of the complexity of human genetics, Dictyostelium and HL60 cells have long served as models system for studying chemotaxis. Since many of our current insights into chemotaxis have been gained from these two model systems, we decided to compare them side by side in a set of winner-take-all races, the Dicty World Races. These worldwide competitions challenge researchers to genetically engineer and pharmacologically enhance the model systems to compete in microfluidic racecourses. These races bring together technological innovations in genetic engineering and precision measurement of cell motility. Fourteen teams participated in the inaugural Dicty World Race 2014 and contributed cell lines, which they tuned for enhanced speed and chemotactic accuracy. The race enabled large-scale analyses of chemotaxis in complex environments and revealed an intriguing balance of speed and accuracy of the model cell lines. The successes of the first race validated the concept of using fun-spirited competition to gain insights into the complex mechanisms controlling chemotaxis, while the challenges of the first race will guide further technological development and planning of future events.

  16. Squid-derived chitin oligosaccharides are a chemotactic signal during colonization by Vibrio fischeri.

    Science.gov (United States)

    Mandel, Mark J; Schaefer, Amy L; Brennan, Caitlin A; Heath-Heckman, Elizabeth A C; Deloney-Marino, Cindy R; McFall-Ngai, Margaret J; Ruby, Edward G

    2012-07-01

    Chitin, a polymer of N-acetylglucosamine (GlcNAc), is noted as the second most abundant biopolymer in nature. Chitin serves many functions for marine bacteria in the family Vibrionaceae ("vibrios"), in some instances providing a physical attachment site, inducing natural genetic competence, and serving as an attractant for chemotaxis. The marine luminous bacterium Vibrio fischeri is the specific symbiont in the light-emitting organ of the Hawaiian bobtail squid, Euprymna scolopes. The bacterium provides the squid with luminescence that the animal uses in an antipredatory defense, while the squid supports the symbiont's nutritional requirements. V. fischeri cells are harvested from seawater during each host generation, and V. fischeri is the only species that can complete this process in nature. Furthermore, chitin is located in squid hemocytes and plays a nutritional role in the symbiosis. We demonstrate here that chitin oligosaccharides produced by the squid host serve as a chemotactic signal for colonizing bacteria. V. fischeri uses the gradient of host chitin to enter the squid light organ duct and colonize the animal. We provide evidence that chitin serves a novel function in an animal-bacterial mutualism, as an animal-produced bacterium-attracting synomone.

  17. Motility and chemotactic response of Pseudomonas fluorescens toward chemoattractants present in the exudate of Macrophomina phaseolina.

    Science.gov (United States)

    Singh, T; Arora, D K

    2001-01-01

    Pseudomonas fluorescens strains (LAM1-hydrophilic) and (LAM2-hydrophobic) showed positive chemotaxis towards attractants (sugars, amino acids, polyols and organic acids) present in the exudate of Macrophomina phaseolina (a soil-borne plant pathogenic fungus). The varied response of motility traits such as speed, rate of change in direction (RCDI) and net to gross displacement ratio (NGDR) was observed for different chemoattractants. Swimming speed of the strains was highest in 10-fold diluted exudate or 100-1000 microM strength of different attractants, but further dilutions significantly decreased the swimming speed (P = 0.05). Chemotactic response of P fluorescens was positively correlated with swimming speed (P = 0.05; r = 0.76). Relative to control, the RCDI values decreased 1.5-fold in amino acids or sugars, and 1.2-fold in polyols or organic acids. With increase in swimming speed, the NGDR of both strains also increased, but the RCDI decreased. Both hydrophilic and hydrophobic strains did not show significant differences in their motility traits. The results demonstrate that M. phaseolina exudate contains chemical attractants that serve as signal for flagellar motility of P. fluorescens. Motile P fluorescens strains thus may consume fungal exudate as nutrients, and thus spores could offer a niche for these bacteria in soil.

  18. A chemotactic gradient sequestered on endothelial heparan sulfate induces directional intraluminal crawling of neutrophils.

    Science.gov (United States)

    Massena, Sara; Christoffersson, Gustaf; Hjertström, Elina; Zcharia, Eyal; Vlodavsky, Israel; Ausmees, Nora; Rolny, Charlotte; Li, Jin-Ping; Phillipson, Mia

    2010-09-16

    During infection, chemokines sequestered on endothelium induce recruitment of circulating leukocytes into the tissue where they chemotax along chemokine gradients toward the afflicted site. The aim of this in vivo study was to determine whether a chemokine gradient was formed intravascularly and influenced intraluminal neutrophil crawling and transmigration. A chemokine gradient was induced by placing a macrophage inflammatory protein-2 (MIP-2)-containing (CXCL2) gel on the cremaster muscle of anesthetized wild-type mice or heparanase-overexpressing transgenic mice (hpa-tg) with truncated heparan sulfate (HS) side chains. Neutrophil-endothelial interactions were visualized by intravital microscopy and chemokine gradients detected by confocal microscopy. Localized extravascular chemokine release (MIP-2 gel) induced directed neutrophil crawling along a chemotactic gradient immobilized on the endothelium and accelerated their recruitment into the target tissue compared with homogeneous extravascular chemokine concentration (MIP-2 superfusion). Endothelial chemokine sequestration occurred exclusively in venules and was HS-dependent, and neutrophils in hpa-tg mice exhibited random crawling. Despite similar numbers of adherent neutrophils in hpa-tg and wild-type mice, the altered crawling in hpa-tg mice was translated into decreased number of emigrated neutrophils and ultimately decreased the ability to clear bacterial infections. In conclusion, an intravascular chemokine gradient sequestered by endothelial HS effectively directs crawling leukocytes toward transmigration loci close to the infection site.

  19. Inferring the Chemotactic Strategy of P. putida and E. coli Using Modified Kramers-Moyal Coefficients

    Science.gov (United States)

    Hintsche, Marius; Beta, Carsten; Stark, Holger

    2017-01-01

    Many bacteria perform a run-and-tumble random walk to explore their surrounding and to perform chemotaxis. In this article we present a novel method to infer the relevant parameters of bacterial motion from experimental trajectories including the tumbling events. We introduce a stochastic model for the orientation angle, where a shot-noise process initiates tumbles, and analytically calculate conditional moments, reminiscent of Kramers-Moyal coefficients. Matching them with the moments calculated from experimental trajectories of the bacteria E. coli and Pseudomonas putida, we are able to infer their respective tumble rates, the rotational diffusion constants, and the distributions of tumble angles in good agreement with results from conventional tumble recognizers. We also define a novel tumble recognizer, which explicitly quantifies the error in recognizing tumbles. In the presence of a chemical gradient we condition the moments on the bacterial direction of motion and thereby explore the chemotaxis strategy. For both bacteria we recover and quantify the classical chemotactic strategy, where the tumble rate is smallest along the chemical gradient. In addition, for E. coli we detect some cells, which bias their mean tumble angle towards smaller values. Our findings are supported by a scaling analysis of appropriate ratios of conditional moments, which are directly calculated from experimental data. PMID:28114420

  20. Hydrocarbon biodegradation and dynamic laser speckle for detecting chemotactic responses at low bacterial concentration

    Institute of Scientific and Technical Information of China (English)

    Melina Nisenbaum; Gonzalo Hernán Sendra; Gastón Alfredo Cerdá Gilbert; Marcelo Scagliola; Jorge Froilán González; Silvia Elena Murialdo

    2013-01-01

    We report on the biodegradation of pure hydrocarbons and chemotaxis towards these compounds by an isolated chlorophenol degrader,Pseudomonas strain H.The biochemical and phylogenetic analysis of the 16S rDNA sequence identified Pseudomonas strain H as having 99.56% similarity with P.aeruginosa PA01.This strain was able to degrade n-hexadecane,1-undecene,1-nonene,1-decene,1-dodecene and kerosene.It grew in the presence of 1-octene,while this hydrocarbons is toxic to other hydrocarbons degraders.Pseudomonas strain H was also chemotactic towards n-hexadecane,kerosene,1-undecene and 1-dodecene.These results show that this Pseudomonas strain H is an attractive candidate for hydrocarbon-containing wastewater bioremediation in controlled environments.Since the classical standard techniques for detecting chemotaxis are not efficient at low bacterial concentrations,we demonstrate the use of the dynamic speckle laser method,which is simple and inexpensive,to confirm bacterial chemotaxis at low cell concentrations (less than 105 colony-forming unit per millilitre (CFU/mL)) when hydrocarbons are the attractants.

  1. Bound attractant at the leading vs. the trailing edge determines chemotactic prowess.

    Science.gov (United States)

    Herzmark, Paul; Campbell, Kyle; Wang, Fei; Wong, Kit; El-Samad, Hana; Groisman, Alex; Bourne, Henry R

    2007-08-14

    We have analyzed chemotaxis of neutrophil-differentiated HL60 cells in microfluidic devices that create exponential gradients of the chemoattractant, f-Met-Leu-Phe (fMLP). Such gradients expose each cell to a difference in fMLP concentration (DeltaC) across its diameter that is directly proportional to the ambient concentration (C) at that cell's position in the gradient, so the ratio DeltaC/C is constant everywhere. Cells exposed to ambient fMLP concentrations near the constant of dissociation (K(d)) for fMLP binding to its receptor ( approximately 10 nM) crawl much less frequently when DeltaC/C is 0.05 than when it is 0.09 or 0.13. Hence, cells can detect the gradient across their diameter without moving and, thus, without experiencing temporal changes in attractant concentration. At all DeltaC/C ratios tested, the average chemotactic prowess of individual cells (indicated by the distance a cell traveled in the correct direction divided by the length of its migration path) is maximal for cells that start migrating at concentrations near the K(d) and progressively decreases at higher or lower starting concentrations.

  2. Wave Patterns in Cell Membrane and Actin Cortex Uncoupled from Chemotactic Signals.

    Science.gov (United States)

    Gerisch, Günther; Ecke, Mary

    2016-01-01

    When cells of Dictyostelium discoideum orientate in a gradient of chemoattractant, they are polarized into a protruding front pointing toward the source of attractant, and into a retracting tail. Under the control of chemotactic signal inputs, Ras is activated and PIP3 is synthesized at the front, while the PIP3-degrading phosphatase PTEN decorates the tail region. As a result of signal transduction, actin filaments assemble at the front into dendritic structures associated with the Arp2/3 complex, in contrast to the tail region where a loose actin meshwork is associated with myosin-II and cortexillin, an antiparallel actin-bundling protein. In axenically growing strains of D. discoideum, wave patterns built by the same components evolve in the absence of any external signal input. Since these autonomously generated patterns are constrained to the plane of the substrate-attached cell surface, they are optimally suited to the optical analysis of state transitions between front-like and tail-like states of the membrane and the actin cortex. Here, we describe imaging techniques using fluorescent proteins to probe for the state of the membrane, the reorganization of the actin network, and the dynamics of wave patterns.

  3. Emerging morphologies in round bacterial colonies: comparing volumetric versus chemotactic expansion.

    Science.gov (United States)

    Giverso, Chiara; Verani, Marco; Ciarletta, Pasquale

    2016-06-01

    Biological experiments performed on living bacterial colonies have demonstrated the microbial capability to develop finger-like shapes and highly irregular contours, even starting from an homogeneous inoculum. In this work, we study from the continuum mechanics viewpoint the emergence of such branched morphologies in an initially circular colony expanding on the top of a Petri dish coated with agar. The bacterial colony expansion, based on either a source term, representing volumetric mitotic processes, or a nonconvective mass flux, describing chemotactic expansion, is modeled at the continuum scale. We demonstrate that the front of the colony is always linearly unstable, having similar dispersion curves to the ones characterizing branching instabilities. We also perform finite element simulations, which not only prove the emergence of branching, but also highlight dramatic differences between the two mechanisms of colony expansion in the nonlinear regime. Furthermore, the proposed combination of analytical and numerical analysis allowed studying the influence of different model parameters on the selection of specific patterns. A very good agreement has been found between the resulting simulations and the typical structures observed in biological assays. Finally, this work provides a new interpretation of the emergence of branched patterns in living aggregates, depicted as the results of a complex interplay among chemical, mechanical and size effects.

  4. A multidomain hub anchors the chromosome segregation and chemotactic machinery to the bacterial pole.

    Science.gov (United States)

    Yamaichi, Yoshiharu; Bruckner, Raphael; Ringgaard, Simon; Möll, Andrea; Cameron, D Ewen; Briegel, Ariane; Jensen, Grant J; Davis, Brigid M; Waldor, Matthew K

    2012-10-15

    The cell poles constitute key subcellular domains that are often critical for motility, chemotaxis, and chromosome segregation in rod-shaped bacteria. However, in nearly all rods, the processes that underlie the formation, recognition, and perpetuation of the polar domains are largely unknown. Here, in Vibrio cholerae, we identified HubP (hub of the pole), a polar transmembrane protein conserved in all vibrios, that anchors three ParA-like ATPases to the cell poles and, through them, controls polar localization of the chromosome origin, the chemotactic machinery, and the flagellum. In the absence of HubP, oriCI is not targeted to the cell poles, chemotaxis is impaired, and a small but increased fraction of cells produces multiple, rather than single, flagella. Distinct cytoplasmic domains within HubP are required for polar targeting of the three ATPases, while a periplasmic portion of HubP is required for its localization. HubP partially relocalizes from the poles to the mid-cell prior to cell division, thereby enabling perpetuation of the polar domain in future daughter cells. Thus, a single polar hub is instrumental for establishing polar identity and organization.

  5. Hydrocarbon biodegradation and dynamic laser speckle for detecting chemotactic responses at low bacterial concentration.

    Science.gov (United States)

    Nisenbaum, Melina; Sendra, Gonzalo Hernán; Gilbert, Gastón Alfredo Cerdá; Scagliola, Marcelo; González, Jorge Froilán; Murialdo, Silvia Elena

    2013-03-01

    We report on the biodegradation of pure hydrocarbons and chemotaxis towards these compounds by an isolated chlorophenol degrader, Pseudomonas strain H. The biochemical and phylogenetic analysis of the 16S rDNA sequence identified Pseudomonas strain H as having 99.56% similarity with P. aeruginosa PA01. This strain was able to degrade n-hexadecane, 1-undecene, 1-nonene, 1-decene, 1-dodecene and kerosene. It grew in the presence of 1-octene, while this hydrocarbons is toxic to other hydrocarbons degraders. Pseudomonas strain H was also chemotactic towards n-hexadecane, kerosene, 1-undecene and 1-dodecene. These results show that this Pseudomonas strain H is an attractive candidate for hydrocarbon-containing wastewater bioremediation in controlled environments. Since the classical standard techniques for detecting chemotaxis are not efficient at low bacterial concentrations, we demonstrate the use of the dynamic speckle laser method, which is simple and inexpensive, to confirm bacterial chemotaxis at low cell concentrations (less than 10(5) colony-forming unit per millilitre (CFU/mL)) when hydrocarbons are the attractants.

  6. Investigations into the design principles in the chemotactic behavior of Escherichia coli.

    Science.gov (United States)

    Kim, Tae-Hwan; Jung, Sung Hoon; Cho, Kwang-Hyun

    2008-01-01

    Inspired by the recent studies on the analysis of biased random walk behavior of Escherichia coli[Passino, K.M., 2002. Biomimicry of bacterial foraging for distributed optimization and control. IEEE Control Syst. Mag. 22 (3), 52-67; Passino, K.M., 2005. Biomimicry for Optimization, Control and Automation. Springer-Verlag, pp. 768-798; Liu, Y., Passino, K.M., 2002. Biomimicry of social foraging bacteria for distributed optimization: models, principles, and emergent behaviors. J. Optim. Theory Appl. 115 (3), 603-628], we have developed a model describing the motile behavior of E. coli by specifying some simple rules on the chemotaxis. Based on this model, we have analyzed the role of some key parameters involved in the chemotactic behavior to unravel the underlying design principles. By investigating the target tracking capability of E. coli in a maze through computer simulations, we found that E. coli clusters can be controlled as target trackers in a complex micro-scale-environment. In addition, we have explored the dynamical characteristics of this target tracking mechanism through perturbation of parameters under noisy environments. It turns out that the E. coli chemotaxis mechanism might be designed such that it is sensitive enough to efficiently track the target and also robust enough to overcome environmental noises.

  7. Moving forward moving backward: directional sorting of chemotactic cells due to size and adhesion differences.

    Directory of Open Access Journals (Sweden)

    Jos Käfer

    2006-06-01

    Full Text Available Differential movement of individual cells within tissues is an important yet poorly understood process in biological development. Here we present a computational study of cell sorting caused by a combination of cell adhesion and chemotaxis, where we assume that all cells respond equally to the chemotactic signal. To capture in our model mesoscopic properties of biological cells, such as their size and deformability, we use the Cellular Potts Model, a multiscale, cell-based Monte Carlo model. We demonstrate a rich array of cell-sorting phenomena, which depend on a combination of mescoscopic cell properties and tissue level constraints. Under the conditions studied, cell sorting is a fast process, which scales linearly with tissue size. We demonstrate the occurrence of "absolute negative mobility", which means that cells may move in the direction opposite to the applied force (here chemotaxis. Moreover, during the sorting, cells may even reverse the direction of motion. Another interesting phenomenon is "minority sorting", where the direction of movement does not depend on cell type, but on the frequency of the cell type in the tissue. A special case is the cAMP-wave-driven chemotaxis of Dictyostelium cells, which generates pressure waves that guide the sorting. The mechanisms we describe can easily be overlooked in studies of differential cell movement, hence certain experimental observations may be misinterpreted.

  8. Anti-coreceptor therapy drives selective T cell egress by suppressing inflammation-dependent chemotactic cues

    Science.gov (United States)

    Martin, Aaron J.; Clark, Matthew; Gojanovich, Gregory; Manzoor, Fatima; Miller, Keith; Kline, Douglas E.; Morillon, Y. Maurice; Wang, Bo

    2016-01-01

    There continues to be a need for immunotherapies to treat type 1 diabetes in the clinic. We previously reported that nondepleting anti-CD4 and -CD8 Ab treatment effectively reverses diabetes in new-onset NOD mice. A key feature of the induction of remission is the egress of the majority of islet-resident T cells. How this occurs is undefined. Herein, the effects of coreceptor therapy on islet T cell retention were investigated. Bivalent Ab binding to CD4 and CD8 blocked TCR signaling and T cell cytokine production, while indirectly downregulating islet chemokine expression. These processes were required for T cell retention, as ectopic IFN-γ or CXCL10 inhibited Ab-mediated T cell purging. Importantly, treatment of humanized mice with nondepleting anti–human CD4 and CD8 Ab similarly reduced tissue-infiltrating human CD4+ and CD8+ T cells. These findings demonstrate that Ab binding of CD4 and CD8 interrupts a feed-forward circuit by suppressing T cell–produced cytokines needed for expression of chemotactic cues, leading to rapid T cell egress from the islets. Coreceptor therapy therefore offers a robust approach to suppress T cell–mediated pathology by purging T cells in an inflammation-dependent manner.

  9. Comamonas testosteroni uses a chemoreceptor for tricarboxylic acid cycle intermediates to trigger chemotactic responses towards aromatic compounds.

    Science.gov (United States)

    Ni, Bin; Huang, Zhou; Fan, Zheng; Jiang, Cheng-Ying; Liu, Shuang-Jiang

    2013-11-01

    Bacterial chemotaxis towards aromatic compounds has been frequently observed; however, knowledge of how bacteria sense aromatic compounds is limited. Comamonas testosteroni CNB-1 is able to grow on a range of aromatic compounds. This study investigated the chemotactic responses of CNB-1 to 10 aromatic compounds. We constructed a chemoreceptor-free, non-chemotactic mutant, CNB-1Δ20, by disruption of all 19 putative methyl-accepting chemotaxis proteins (MCPs) and the atypical chemoreceptor in strain CNB-1. Individual complementation revealed that a putative MCP (tagged MCP2201) was involved in triggering chemotaxis towards all 10 aromatic compounds. The recombinant sensory domain of MCP2201 did not bind to 3- or 4-hydroxybenzoate, protocatechuate, catechol, benzoate, vanillate and gentisate, but bound oxaloacetate, citrate, cis-aconitate, isocitrate, α-ketoglutarate, succinate, fumarate and malate. The mutant CNB-1ΔpmdF that lost the ability to metabolize 4-hydroxybenzoate and protocatechuate also lost its chemotactic response to these compounds, suggesting that taxis towards aromatic compounds is metabolism-dependent. Based on the ligand profile, we proposed that MCP2201 triggers taxis towards aromatic compounds by sensing TCA cycle intermediates. Our hypothesis was further supported by the finding that introduction of the previously characterized pseudomonad chemoreceptor (McpS) for TCA cycle intermediates into CNB-1Δ20 likewise triggered chemotaxis towards aromatic compounds.

  10. The Bacillus anthracis cholesterol-dependent cytolysin, Anthrolysin O, kills human neutrophils, monocytes and macrophages

    Directory of Open Access Journals (Sweden)

    Rest Richard F

    2006-06-01

    Full Text Available Abstract Background Bacillus anthracis is an animal and human pathogen whose virulence is characterized by lethal and edema toxin, as well as a poly-glutamic acid capsule. In addition to these well characterized toxins, B. anthracis secretes several proteases and phospholipases, and a newly described toxin of the cholesterol-dependent cytolysin (CDC family, Anthrolysin O (ALO. Results In the present studies we show that recombinant ALO (rALO or native ALO, secreted by viable B. anthracis, is lethal to human primary polymorphonuclear leukocytes (PMNs, monocytes, monocyte-derived macrophages (MDMs, lymphocytes, THP-1 monocytic human cell line and ME-180, Detroit 562, and A549 epithelial cells by trypan blue exclusion or lactate dehydrogenase (LDH release viability assays. ALO cytotoxicity is dose and time dependent and susceptibility to ALO-mediated lysis differs between cell types. In addition, the viability of monocytes and hMDMs was assayed in the presence of vegetative Sterne strains 7702 (ALO+, UT231 (ALO-, and a complemented strain expressing ALO, UT231 (pUTE544, and was dependent upon the expression of ALO. Cytotoxicity of rALO is seen as low as 0.070 nM in the absence of serum. All direct cytotoxic activity is inhibited by the addition of cholesterol or serum concentration as low as 10%. Conclusion The lethality of rALO and native ALO on human monocytes, neutrophils, macrophages and lymphocytes supports the idea that ALO may represent a previously unidentified virulence factor of B. anthracis. The study of other factors produced by B. anthracis, along with the major anthrax toxins, will lead to a better understanding of this bacterium's pathogenesis, as well as provide information for the development of antitoxin vaccines for treating and preventing anthrax.

  11. Influence of peripheral blood microparticles of pregnant women with preeclampsia on the phenotype of monocytes.

    Science.gov (United States)

    Sokolov, Dmitriy I; Ovchinnikova, Olga M; Korenkov, Daniil A; Viknyanschuk, Alice N; Benken, Konstantin A; Onokhin, Kirril V; Selkov, Sergey A

    2016-04-01

    Platelet- and endothelial-derived microparticles influence the phenotype of peripheral blood leukocytes and induce production of proinflammatory cytokines. The influence of blood plasma microparticles of pregnant women on the surface receptor expression on intact or activated monocytes is still unexplored. This study was carried out to test the hypothesis that peripheral blood microparticles of women with normal pregnancy and women with preeclampsia have different influence on the expression of surface molecules on monocytes. The objective of the study was to evaluate the influence of blood plasma microparticles of pregnant women on the phenotypic properties of intact and activated THP-1 monocytes. Microparticles were isolated from peripheral blood samples of nonpregnant women, healthy pregnant women, and women with preeclampsia. THP-1 cell line was used as a model of monocytes. Microparticles of nonpregnant women decreased CD18, CD49d, and CD54 expressions and increased CD11c, CD31, CD47, and vascular endothelial growth factor receptor 2 expressions. Microparticles of healthy pregnant women increased CD18, CD54, and integrin β7 expressions and decreased CD11a and CD29 expressions. Microparticles of women with preeclampsia decreased CD18 expression on tumor necrosis factor α (TNF-α)-activated ТНР-1 cells. Microparticles of nonpregnant women, women with normal pregnancy, and pregnant women with preeclampsia decreased CD181 expression on intact and TNF-α-activated THP-1 cells. Therefore, blood plasma microparticles of women with normal pregnancy and women with preeclampsia have different influences on the expression of surface molecules on THP-1 monocytes.

  12. Proteome of monocyte priming by lipopolysaccharide, including changes in interleukin-1beta and leukocyte elastase inhibitor

    Directory of Open Access Journals (Sweden)

    Beranova-Giorgianni Sarka

    2008-05-01

    Full Text Available Abstract Background Monocytes can be primed in vitro by lipopolysaccharide (LPS for release of cytokines, for enhanced killing of cancer cells, and for enhanced release of microbicidal oxygen radicals like superoxide and peroxide. We investigated the proteins involved in regulating priming, using 2D gel proteomics. Results Monocytes from 4 normal donors were cultured for 16 h in chemically defined medium in Teflon bags ± LPS and ± 4-(2-aminoethyl-benzenesulfonyl fluoride (AEBSF, a serine protease inhibitor. LPS-primed monocytes released inflammatory cytokines, and produced increased amounts of superoxide. AEBSF blocked priming for enhanced superoxide, but did not affect cytokine release, showing that AEBSF was not toxic. After staining large-format 2D gels with Sypro ruby, we compared the monocyte proteome under the four conditions for each donor. We found 30 protein spots that differed significantly in response to LPS or AEBSF, and these proteins were identified by ion trap mass spectrometry. Conclusion We identified 19 separate proteins that changed in response to LPS or AEBSF, including ATP synthase, coagulation factor XIII, ferritin, coronin, HN ribonuclear proteins, integrin alpha IIb, pyruvate kinase, ras suppressor protein, superoxide dismutase, transketolase, tropomyosin, vimentin, and others. Interestingly, in response to LPS, precursor proteins for interleukin-1β appeared; and in response to AEBSF, there was an increase in elastase inhibitor. The increase in elastase inhibitor provides support for our hypothesis that priming requires an endogenous serine protease.

  13. [Induction of monocyte-derived dendritic cell differentiation by asthmatic serum in a transendothelial trafficking model].

    Science.gov (United States)

    Zhou, Lin-fu; Wang, Wen-lu; Li, Hong-yan; Zhang, Ming-shun; Ji, Xiao-hui; He, Shao-heng; Huang, Mao; Yin, Kai-sheng

    2011-03-01

    To explore the effect of asthmatic and healthy serum on differentiation and function of monocyte-derived dendritic cells (MDDC) in a transendothelial trafficking model. The sera and peripheral blood mononuclear cells (PBMC) were separated from 12 asthmatic patients and 12 healthy volunteers, and monocytes were selected from PBMC using magnetic beads. The trypsin-digested human umbilical vein endothelial cells (HUVEC) at passage 2 from 5 healthy lying-in women were used to construct the transendothelial trafficking model under asthmatic or healthy serum, wherein MDDC were identified by silver nitrate staining and scanning electron microscopy. Nuclear factor κB (NF-κB) activity was determined by electrophoretic mobility shift assay. Flow cytometry, ELISA and mixed leukocyte reaction were relevantly utilized to detect the phenotype, cytokine and T cell proliferation. (1) Monocytes traversed through HUVEC monolayer after 2 h, and reverse-transmigrated to develop into DC 48 h later. (2) The healthy serum stimulated monocytes into immature MDDC with lower CD(14) [(20 ± 5)%] (F = 49.01, P 0.05), higher CD(80) and CD(83) [(49.7 ± 10.2)% and (30.2 ± 6.8)%] (F = 4.01 and 20.68, all P trafficking model, which provides a promising experimental platform for both investigation of immunological mechanisms in asthma and screening of novel anti-asthma drugs in vitro.

  14. Biologic therapy improves psoriasis by decreasing the activity of monocytes and neutrophils.

    Science.gov (United States)

    Yamanaka, Keiichi; Umezawa, Yoshinori; Yamagiwa, Akisa; Saeki, Hidehisa; Kondo, Makoto; Gabazza, Esteban C; Nakagawa, Hidemi; Mizutani, Hitoshi

    2014-08-01

    Therapy with monoclonal antibodies to tumor necrosis factor (TNF)-α and the interleukin (IL)-12/23 p40 subunit has significantly improved the clinical outcome of patients with psoriasis. These antibodies inhibit the effects of the target cytokines and thus the major concern during their use is the induction of excessive immunosuppression. Recent studies evaluating the long-term efficacy and safety of biologic therapy in psoriasis have shown no significant appearance of serious adverse effects including infections and malignancies. However, the immunological consequence and the mechanism by which the blockade of a single cytokine by biologics can successfully control the activity of psoriasis remain unclear. In the current study, we investigated the effect of biologic therapy on cytokine production of various lymphocytes and on the activity of monocytes and neutrophils in psoriatic patients. Neutrophils, monocytes and T cells were purified from heparinized peripheral venous blood by Ficoll density gradient centrifugation, and γ-interferon, TNF-α and IL-17 production from lymphocytes was measured by flow cytometer. The activation maker of neutrophils and the activated subsets of monocytes were also analyzed. Biologic therapy induced no significant changes in the cytokine production by lymphocytes from the skin and gut-homing T cells. However, neutrophil activity and the ratio of activated monocyte population increased in severely psoriatic patients were normalized in psoriatic patients receiving biologic therapy. The present study showed that biologic therapy ameliorates clinical symptoms and controls the immune response in patients with psoriasis.

  15. HSV-1-induced activation of NF-κB protects U937 monocytic cells against both virus replication and apoptosis.

    Science.gov (United States)

    Marino-Merlo, Francesca; Papaianni, Emanuela; Medici, Maria Antonietta; Macchi, Beatrice; Grelli, Sandro; Mosca, Claudia; Borner, Christoph; Mastino, Antonio

    2016-09-01

    The transcription factor nuclear factor-kappa B (NF-κB) is a crucial player of the antiviral innate response. Intriguingly, however, NF-κB activation is assumed to favour herpes simplex virus (HSV) infection rather than restrict it. Apoptosis, a form of innate response to viruses, is completely inhibited by HSV in fully permissive cells, but not in cells incapable to fully sustain HSV replication, such as immunocompetent cells. To resolve the intricate interplay among NF-κB signalling, apoptosis and permissiveness to HSV-1 in monocytic cells, we utilized U937 monocytic cells in which NF-κB activation was inhibited by expressing a dominant-negative IκBα. Surprisingly, viral production was increased in monocytic cells in which NF-κB was inhibited. Moreover, inhibition of NF-κB led to increased apoptosis following HSV-1 infection, associated with lysosomal membrane permeabilization. High expression of late viral proteins and induction of apoptosis occurred in distinct cells. Transcriptional analysis of known innate response genes by real-time quantitative reverse transcription-PCR excluded a contribution of the assayed genes to the observed phenomena. Thus, in monocytic cells NF-κB activation simultaneously serves as an innate process to restrict viral replication as well as a mechanism to limit the damage of an excessive apoptotic response to HSV-1 infection. This finding may clarify mechanisms controlling HSV-1 infection in monocytic cells.

  16. Differential control of Helios+/− Treg development by monocyte subsets through disparate inflammatory cytokines

    OpenAIRE

    Zhong, Hui; Yazdanbakhsh, Karina

    2013-01-01

    Control of Helios+/− Treg subset development is mediated through distinct cytokines and monocyte subpopulations.CD16+ monocytes inhibit Helios+ Treg proliferation through IL-12, whereas CD16− monocytes suppress Helios− Treg development through TNF-α.

  17. DMPD: Monocyte/macrophage traffic in HIV and SIV encephalitis. [Dynamic Macrophage Pathway CSML Database

    Lifescience Database Archive (English)

    Full Text Available 12960230 Monocyte/macrophage traffic in HIV and SIV encephalitis. Kim WK, Corey S, ...Show Monocyte/macrophage traffic in HIV and SIV encephalitis. PubmedID 12960230 Title Monocyte/macrophage traffic

  18. Migration of monocytes after intracerebral injection.

    Science.gov (United States)

    Kaminski, Miriam; Bechmann, Ingo; Kiwit, Jürgen; Glumm, Jana

    2012-01-01

    Recently, we monitored green fluorescent protein (GFP)-expressing monocytes after injection at the entorhinal cortex lesion (ECL) site in mice. We followed their migration out of the central nervous system (CNS) along olfactory nerve fibers penetrating the lamina cribrosa, within the nasal mucosa, and their subsequent appearance within the deep cervical lymph nodes (CLN), with numbers peaking at day 7. This is the same route activated T cells use for reaching the CLN, as we have shown before. Interestingly, GFP cells injected into the brain and subsequently found in the CLN exhibited ramified morphologies, which are typical of microglia and dendritic cells. To gain more insight into immunity and regeneration within the CNS we want to monitor injected monocytes using magnetic resonance imaging (MRI) after labeling with very small superparamagnetic iron oxide particles (VSOP). Due to their small size, nanoparticles have huge potential for magnetic labeling of different cell populations and their MRI tracking in vivo. So far we have verified that incubation with VSOP particles does not alter their migration pattern after ECL.

  19. Comparative Analysis of the Interaction of Helicobacter pylori with Human Dendritic Cells, Macrophages, and Monocytes

    Science.gov (United States)

    Fehlings, Michael; Drobbe, Lea; Moos, Verena; Renner Viveros, Pablo; Hagen, Jana; Beigier-Bompadre, Macarena; Pang, Ervinna; Belogolova, Elena; Churin, Yuri; Schneider, Thomas; Meyer, Thomas F.; Aebischer, Toni

    2012-01-01

    Helicobacter pylori may cause chronic gastritis, gastric cancer, or lymphoma. Myeloid antigen-presenting cells (APCs) are most likely involved in the induction and expression of the underlying inflammatory responses. To study the interaction of human APC subsets with H. pylori, we infected monocytes, monocyte-derived dendritic cells (DCs), and monocyte-derived (classically activated; M1) macrophages with H. pylori and analyzed phenotypic alterations, cytokine secretion, phagocytosis, and immunostimulation. Since we detected CD163+ (alternatively activated; M2) macrophages in gastric biopsy specimens from H. pylori-positive patients, we also included monocyte-derived M2 macrophages in the study. Upon H. pylori infection, monocytes secreted interleukin-1β (IL-1β), IL-6, IL-10, and IL-12p40 (partially secreted as IL-23) but not IL-12p70. Infected DCs became activated, as shown by the enhanced expression of CD25, CD80, CD83, PDL-1, and CCR7, and secreted IL-1β, IL-6, IL-10, IL-12p40, IL-12p70, and IL-23. However, infection led to significantly downregulated CD209 and suppressed the constitutive secretion of macrophage migration inhibitory factor (MIF). H. pylori-infected M1 macrophages upregulated CD14 and CD32, downregulated CD11b and HLA-DR, and secreted mainly IL-1β, IL-6, IL-10, IL-12p40, and IL-23. Activation of DCs and M1 macrophages correlated with increased capacity to induce T-cell proliferation and decreased phagocytosis of dextran. M2 macrophages upregulated CD14 and CD206 and secreted IL-10 but produced less of the proinflammatory cytokines than M1 macrophages. Thus, H. pylori affects the functions of human APC subsets differently, which may influence the course and the outcome of H. pylori infection. The suppression of MIF in DCs constitutes a novel immune evasion mechanism exploited by H. pylori. PMID:22615251

  20. CD14{sup +} monocytes promote the immunosuppressive effect of human umbilical cord matrix stem cells

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Ding, E-mail: qqhewd@gmail.com [The State Key Laboratory of Experimental Hematology, Institute of Hematology and Hospital of Blood Diseases, Chinese Academy of Medical Sciences and Peking Union of Medical College, 288 Nanjing Road, Tianjin 300020 (China); TEDA Life and Technology Research Center, Institute of Hematology, Chinese Academy of Medical Sciences, TEDA, Tianjin (China); Chen, Ke, E-mail: chenke_59@hotmail.com [The State Key Laboratory of Experimental Hematology, Institute of Hematology and Hospital of Blood Diseases, Chinese Academy of Medical Sciences and Peking Union of Medical College, 288 Nanjing Road, Tianjin 300020 (China); TEDA Life and Technology Research Center, Institute of Hematology, Chinese Academy of Medical Sciences, TEDA, Tianjin (China); Du, Wei Ting, E-mail: duwtpumc@yahoo.com.cn [The State Key Laboratory of Experimental Hematology, Institute of Hematology and Hospital of Blood Diseases, Chinese Academy of Medical Sciences and Peking Union of Medical College, 288 Nanjing Road, Tianjin 300020 (China); Han, Zhi-Bo, E-mail: zhibohan@hotmail.com [The State Key Laboratory of Experimental Hematology, Institute of Hematology and Hospital of Blood Diseases, Chinese Academy of Medical Sciences and Peking Union of Medical College, 288 Nanjing Road, Tianjin 300020 (China); TEDA Life and Technology Research Center, Institute of Hematology, Chinese Academy of Medical Sciences, TEDA, Tianjin (China); Ren, He, E-mail: knifesharp2000@hotmail.com [National Engineering Research Center of Cell Products, AmCellGene Co. Ltd, TEDA, Tianjin (China); Chi, Ying, E-mail: caizhuying@hotmail.com [The State Key Laboratory of Experimental Hematology, Institute of Hematology and Hospital of Blood Diseases, Chinese Academy of Medical Sciences and Peking Union of Medical College, 288 Nanjing Road, Tianjin 300020 (China); TEDA Life and Technology Research Center, Institute of Hematology, Chinese Academy of Medical Sciences, TEDA, Tianjin (China); and others

    2010-09-10

    Here, the effect of CD14{sup +} monocytes on human umbilical cord matrix stem cell (hUC-MSC)-mediated immunosuppression was studied in vitro. hUC-MSCs exerted a potent inhibitory effect on the proliferation and interferon-{gamma} (IFN-{gamma}) secretion capacities of CD4{sup +} and CD8{sup +} T cells in response to anti-CD3/CD28 stimulation. Transwell co-culture system revealed that the suppressive effect was primarily mediated by soluble factors. Addition of prostaglandin synthesis inhibitors (indomethacin or NS-398) almost completely abrogated the immunosuppression activity of hUC-MSCs, identifying prostaglandin E{sub 2} (PGE{sub 2}) as an important soluble mediator. CD14{sup +} monocytes were found to be able to enhance significantly the immunosuppressive effect of hUC-MSCs in a dose-dependent fashion. Moreover, the inflammatory cytokine IL-1{beta}, either exogenously added or produced by CD14{sup +} monocytes in culture, could trigger expression of high levels of PGE{sub 2} by hUC-MSCs, whereas inclusion of the IL-1 receptor antagonist (IL-1RA) in the culture down-regulated not only PGE{sub 2} expression, but also reversed the promotional effect of CD14{sup +} monocytes and partially restored CD4{sup +} and CD8{sup +} T cell proliferation and IFN-{gamma} secretion. Our data demonstrate an important role of monocytes in the hUC-MSC-induced immunomodulation, which may have important implications in future efforts to explore the clinical potentials of hUC-MSCs.

  1. Design of phosphorylated dendritic architectures to promote human monocyte activation.

    Science.gov (United States)

    Poupot, Mary; Griffe, Laurent; Marchand, Patrice; Maraval, Alexandrine; Rolland, Olivier; Martinet, Ludovic; L'Faqihi-Olive, Fatima-Ezzahra; Turrin, Cédric-Olivier; Caminade, Anne-Marie; Fournié, Jean-Jacques; Majoral, Jean-Pierre; Poupot, Rémy

    2006-11-01

    As first defensive line, monocytes are a pivotal cell population of innate immunity. Monocyte activation can be relevant to a range of immune conditions and responses. Here we present new insights into the activation of monocytes by a series of phosphonic acid-terminated, phosphorus-containing dendrimers. Various dendritic or subdendritic structures were synthesized and tested, revealing the basic structural requirements for monocyte activation. We showed that multivalent character and phosphonic acid capping of dendrimers are crucial for monocyte targeting and activation. Confocal videomicroscopy showed that a fluorescein-tagged dendrimer binds to isolated monocytes and gets internalized within a few seconds. We also found that dendrimers follow the phagolysosomial route during internalization by monocytes. Finally, we performed fluorescence resonance energy transfer (FRET) experiments between a specifically designed fluorescent dendrimer and phycoerythrin-coupled antibodies. We showed that the typical innate Toll-like receptor (TLR)-2 is clearly involved, but not alone, in the sensing of dendrimers by monocytes. In conclusion, phosphorus-containing dendrimers appear as precisely tunable nanobiotools able to target and activate human innate immunity and thus prove to be good candidates to develop new drugs for immunotherapies.

  2. Distinct monocyte Gene-Expression profiles in autoimmune diabetes

    NARCIS (Netherlands)

    R.C. Padmos (Roos); N.C. Schloot (Nanette); H. Beyan (Huriya); C. Ruwhof (Cindy); F.J.T. Staal (Frank); D. de Ridder (Dick); H-J. Aanstoot (Henk-Jan); W.K. Lam-Tse; H.J. de Wit (Harm); C. Herder (Christian); R.C. Drexhage (Roos); B. Menart (Barbara); R.D. Leslie

    2008-01-01

    textabstractOBJECTIVE-There is evidence that monocytes of patients with type 1 diabetes show proinflammatory activation and disturbed migration/adhesion, but the evidence is inconsistent. Our hypothesis is that monocytes are distinctly activated/disturbed in different subforms of autoimmune diabetes

  3. Monocyte Subsets in Schistosomiasis Patients with Periportal Fibrosis

    Directory of Open Access Journals (Sweden)

    Jamille Souza Fernandes

    2014-01-01

    Full Text Available A major issue with Schistosoma mansoni infection is the development of periportal fibrosis, which is predominantly caused by the host immune response to egg antigens. Experimental studies have pointed to the participation of monocytes in the pathogenesis of liver fibrosis. The aim of this study was to characterize the subsets of monocytes in individuals with different degrees of periportal fibrosis secondary to schistosomiasis. Monocytes were classified into classical (CD14++CD16−, intermediate (CD14++CD16+, and nonclassical (CD14+CD16++. The expressions of monocyte markers and cytokines were assessed using flow cytometry. The frequency of classical monocytes was higher than the other subsets. The expression of HLA-DR, IL-6, TNF-α, and TGF-β was higher in monocytes from individuals with moderate to severe fibrosis as compared to other groups. Although no differences were observed in receptors expression (IL-4R and IL-10R between groups of patients, the expression of IL-12 was lower in monocytes from individuals with moderate to severe fibrosis, suggesting a protective role of this cytokine in the development of fibrosis. Our data support the hypothesis that the three different monocyte populations participate in the immunopathogenesis of periportal fibrosis, since they express high levels of proinflammatory and profibrotic cytokines and low levels of regulatory markers.

  4. Monocyte-derived dendritic cells in bipolar disorder

    NARCIS (Netherlands)

    Knijff, EM; Ruwhof, C; de Wit, HJ; Kupka, RW; Vonk, R; Akkerhuis, GW; Nolen, WA; Drexhage, HA

    2006-01-01

    Background: Dendritic cells (DC) are key regulators of the immune system, which is compromised in patients with bipolar disorder. We sought to study monocyte-derived DC in bipolar disorder. Methods: Monocytes purified from blood collected from DSM-IV bipolar disorder outpatients (n = 53, 12 without

  5. Cerebral microglia recruit monocytes into the brain in response to tumor necrosis factoralpha signaling during peripheral organ inflammation.

    Science.gov (United States)

    D'Mello, Charlotte; Le, Tai; Swain, Mark G

    2009-02-18

    In inflammatory diseases occurring outside the CNS, communication between the periphery and the brain via humoral and/or neural routes results in central neural changes and associated behavioral alterations. We have recently identified another immune-to-CNS communication pathway in the setting of organ-centered peripheral inflammation: namely, the entrance of immune cells into the brain. In our current study, using a mouse model of inflammatory liver injury, we have confirmed the significant infiltration of activated monocytes into the brain in mice with hepatic inflammation and have defined the mechanism that mediates this trafficking of monocytes. Specifically, we show that in the presence of hepatic inflammation, mice demonstrate elevated cerebral monocyte chemoattractant protein (MCP)-1 levels, as well as increased numbers of circulating CCR2-expressing monocytes. Cerebral recruitment of monocytes was abolished in inflamed mice that lacked MCP-1/CCL2 or CCR2. Furthermore, in mice with hepatic inflammation, microglia were activated and produced MCP-1/CCL2 before cerebral monocyte infiltration. Moreover, peripheral tumor necrosis factor (TNF)alpha signaling was required to stimulate microglia to produce MCP-1/CCL2. TNFalpha signaling via TNF receptor 1 (TNFR1) is required for these observed effects since in TNFR1 deficient mice with hepatic inflammation, microglial expression of MCP-1/CCL2 and cerebral monocyte recruitment were both markedly inhibited, whereas there was no inhibition in TNFR2 deficient mice. Our results identify the existence of a novel immune-to-CNS communication pathway occurring in the setting of peripheral organ-centered inflammation which may have specific implications for the development of alterations in cerebral neurotransmission commonly encountered in numerous inflammatory diseases occurring outside the CNS.

  6. Cytokine profiles of seventeen cytokines, growth factors and chemokines in cord blood and its relation to perinatal clinical findings.

    Science.gov (United States)

    Takahashi, Naoto; Uehara, Ritei; Kobayashi, Mami; Yada, Yukari; Koike, Yasunori; Kawamata, Ryou; Odaka, Jun; Honma, Yoko; Momoi, Mariko Y

    2010-03-01

    Few papers have investigated the cytokine profiles of multiple cytokines in cord blood. We obtained cord blood samples from 224 infants admitted to our neonatal intensive care unit. Cytokine profiles of 17 cytokines were investigated using cytometric bead array technology. We found a wide variety of cytokines of various levels which ranged from 0.59pg/ml (in Interleukin (IL)-4) to 222.0pg/ml (in macrophage inflammatory protein-1beta. Pro-inflammatory cytokines were highly correlated with each other and with granulocyte-colony stimulating factor and IL-8. On the contrary, IL-5, IL-13, and IL-17 did not show any significant correlation with other cytokines. Several maternal factors were strongly related to several cytokines in cord blood. IL-6, IL-8 and monocyte chemotactic protein-1 were closely related to certain neonatal diseases in preterm neonates. Some cytokines may be regulated independently of each other, while others appear to work as a network affecting physiological and pathological conditions in the fetus.

  7. Chemotactic migration of T cells towards dendritic cells promotes the detection of rare antigens.

    Science.gov (United States)

    Vroomans, Renske M A; Marée, Athanasius F M; de Boer, Rob J; Beltman, Joost B

    2012-01-01

    In many immunological processes chemoattraction is thought to play a role in guiding cells to their sites of action. However, based on in vivo two-photon microscopy experiments in the absence of cognate antigen, T cell migration in lymph nodes (LNs) has been roughly described as a random walk. Although it has been shown that dendritic cells (DCs) carrying cognate antigen in some circumstances attract T cells chemotactically, it is currently still unclear whether chemoattraction of T cells towards DCs helps or hampers scanning. Chemoattraction towards DCs could on the one hand help T cells to rapidly find DCs. On the other hand, it could be deleterious if DCs become shielded by a multitude of attracted yet non-specific T cells. Results from a recent simulation study suggested that the deleterious effect dominates. We re-addressed the question whether T cell chemoattraction towards DCs is expected to promote or hamper the detection of rare antigens using the Cellular Potts Model, a formalism that allows for dynamic, flexible cellular shapes and cell migration. Our simulations show that chemoattraction of T cells enhances the DC scanning efficiency, leading to an increased probability that rare antigen-specific T cells find DCs carrying cognate antigen. Desensitization of T cells after contact with a DC further improves the scanning efficiency, yielding an almost threefold enhancement compared to random migration. Moreover, the chemotaxis-driven migration still roughly appears as a random walk, hence fine-tuned analysis of cell tracks will be required to detect chemotaxis within microscopy data.

  8. Sonic hedgehog is a chemotactic neural crest cell guide that is perturbed by ethanol exposure.

    Science.gov (United States)

    Tolosa, Ezequiel J; Fernández-Zapico, Martín E; Battiato, Natalia L; Rovasio, Roberto A

    2016-01-01

    Our aim was to understand the involvement of Sonic hedgehog (Shh) morphogen in the oriented distribution of neural crest cells (NCCs) toward the optic vesicle and to look for potential disorders of this guiding mechanism after ethanol exposure. In vitro directional analysis showed the chemotactic response of NCCs up Shh gradients and to notochord co-cultures (Shh source) or to their conditioned medium, a response inhibited by anti-Shh antibody, receptor inhibitor cyclopamine and anti-Smo morpholino (MO). Expression of the Ptch-Smo receptor complex on in vitro NCCs was also shown. In whole embryos, the expression of Shh mRNA and protein was seen in the ocular region, and of Ptch, Smo and Gli/Sufu system on cephalic NCCs. Anti-Smo MO or Ptch-mutated plasmid (Ptch1(Δloop2)) impaired cephalic NCC migration/distribution, with fewer cells invading the optic region and with higher cell density at the homolateral mesencephalic level. Beads embedded with cyclopamine (Smo-blocking) or Shh (ectopic signal) supported the role of Shh as an in vivo guide molecule for cephalic NCCs. Ethanol exposure perturbed in vitro and in vivo NCC migration. Early stage embryos treated with ethanol, in a model reproducing Fetal Alcohol Syndrome, showed later disruptions of craniofacial development associated with abnormal in situ expression of Shh morphogen. The results show the Shh/Ptch/Smo-dependent migration of NCCs toward the optic vesicle, with the support of specific inactivation with genetic and pharmacological tools. They also help to understand mechanisms of accurate distribution of embryonic cells and of their perturbation by a commonly consumed teratogen, and demonstrate, in addition to its other known developmental functions, a new biological activity of cellular guidance for Shh.

  9. C1-Inhibitor Decreases the Release of Vasculitis-Like Chemotactic Endothelial Microvesicles.

    Science.gov (United States)

    Mossberg, Maria; Ståhl, Anne-Lie; Kahn, Robin; Kristoffersson, Ann-Charlotte; Tati, Ramesh; Heijl, Caroline; Segelmark, Mårten; Leeb-Lundberg, L M Fredrik; Karpman, Diana

    2017-08-01

    The kinin system is activated during vasculitis and may contribute to chronic inflammation. C1-inhibitor is the main inhibitor of the kinin system. In this study, we investigated the presence of the kinin B1 receptor on endothelial microvesicles and its contribution to the inflammatory process. Compared with controls (n=15), patients with acute vasculitis (n=12) had markedly higher levels of circulating endothelial microvesicles, identified by flow cytometry analysis, and significantly more microvesicles that were positive for the kinin B1 receptor (Pmicrovesicles from wild-type cells, B1 receptor-positive microvesicles derived from transfected human embryonic kidney cells induced a significant neutrophil chemotactic effect, and a B1 receptor antagonist blocked this effect. Likewise, patient plasma induced neutrophil chemotaxis, an effect decreased by reduction of microvesicle levels and by blocking the B1 receptor. We used a perfusion system to study the effect of patient plasma (n=6) and control plasma (n=6) on the release of microvesicles from glomerular endothelial cells. Patient samples induced the release of significantly more B1 receptor-positive endothelial microvesicles than control samples, an effect abrogated by reduction of the microvesicles in the perfused samples. Perfusion of C1-inhibitor-depleted plasma over glomerular endothelial cells promoted excessive release of B1 receptor-positive endothelial microvesicles compared with normal plasma, an effect significantly decreased by addition of C1-inhibitor or B1 receptor-antagonist. Thus, B1 receptor-positive endothelial microvesicles may contribute to chronic inflammation by inducing neutrophil chemotaxis, and the reduction of these microvesicles by C1-inhibitor should be explored as a potential treatment for neutrophil-induced inflammation. Copyright © 2017 by the American Society of Nephrology.

  10. Mytilus galloprovincialis myticin C: a chemotactic molecule with antiviral activity and immunoregulatory properties.

    Science.gov (United States)

    Balseiro, Pablo; Falcó, Alberto; Romero, Alejandro; Dios, Sonia; Martínez-López, Alicia; Figueras, Antonio; Estepa, Amparo; Novoa, Beatriz

    2011-01-01

    Previous research has shown that an antimicrobial peptide (AMP) of the myticin class C (Myt C) is the most abundantly expressed gene in cDNA and suppressive subtractive hybridization (SSH) libraries after immune stimulation of mussel Mytilus galloprovincialis. However, to date, the expression pattern, the antimicrobial activities and the immunomodulatory properties of the Myt C peptide have not been determined. In contrast, it is known that Myt C mRNA presents an unusual and high level of polymorphism of unidentified biological significance. Therefore, to provide a better understanding of the features of this interesting molecule, we have investigated its function using four different cloned and expressed variants of Myt C cDNA and polyclonal anti-Myt C sera. The in vivo results suggest that this AMP, mainly present in hemocytes, could be acting as an immune system modulator molecule because its overexpression was able to alter the expression of mussel immune-related genes (as the antimicrobial peptides Myticin B and Mytilin B, the C1q domain-containing protein MgC1q, and lysozyme). Moreover, the in vitro results indicate that Myt C peptides have antimicrobial and chemotactic properties. Their recombinant expression in a fish cell line conferred protection against two different fish viruses (enveloped and non-enveloped). Cell extracts from Myt C expressing fish cells were also able to attract hemocytes. All together, these results suggest that Myt C should be considered not only as an AMP but also as the first chemokine/cytokine-like molecule identified in bivalves and one of the few examples in all of the invertebrates.

  11. Mytilus galloprovincialis myticin C: a chemotactic molecule with antiviral activity and immunoregulatory properties.

    Directory of Open Access Journals (Sweden)

    Pablo Balseiro

    Full Text Available Previous research has shown that an antimicrobial peptide (AMP of the myticin class C (Myt C is the most abundantly expressed gene in cDNA and suppressive subtractive hybridization (SSH libraries after immune stimulation of mussel Mytilus galloprovincialis. However, to date, the expression pattern, the antimicrobial activities and the immunomodulatory properties of the Myt C peptide have not been determined. In contrast, it is known that Myt C mRNA presents an unusual and high level of polymorphism of unidentified biological significance. Therefore, to provide a better understanding of the features of this interesting molecule, we have investigated its function using four different cloned and expressed variants of Myt C cDNA and polyclonal anti-Myt C sera. The in vivo results suggest that this AMP, mainly present in hemocytes, could be acting as an immune system modulator molecule because its overexpression was able to alter the expression of mussel immune-related genes (as the antimicrobial peptides Myticin B and Mytilin B, the C1q domain-containing protein MgC1q, and lysozyme. Moreover, the in vitro results indicate that Myt C peptides have antimicrobial and chemotactic properties. Their recombinant expression in a fish cell line conferred protection against two different fish viruses (enveloped and non-enveloped. Cell extracts from Myt C expressing fish cells were also able to attract hemocytes. All together, these results suggest that Myt C should be considered not only as an AMP but also as the first chemokine/cytokine-like molecule identified in bivalves and one of the few examples in all of the invertebrates.

  12. Chemotactic migration of T cells towards dendritic cells promotes the detection of rare antigens.

    Directory of Open Access Journals (Sweden)

    Renske M A Vroomans

    Full Text Available In many immunological processes chemoattraction is thought to play a role in guiding cells to their sites of action. However, based on in vivo two-photon microscopy experiments in the absence of cognate antigen, T cell migration in lymph nodes (LNs has been roughly described as a random walk. Although it has been shown that dendritic cells (DCs carrying cognate antigen in some circumstances attract T cells chemotactically, it is currently still unclear whether chemoattraction of T cells towards DCs helps or hampers scanning. Chemoattraction towards DCs could on the one hand help T cells to rapidly find DCs. On the other hand, it could be deleterious if DCs become shielded by a multitude of attracted yet non-specific T cells. Results from a recent simulation study suggested that the deleterious effect dominates. We re-addressed the question whether T cell chemoattraction towards DCs is expected to promote or hamper the detection of rare antigens using the Cellular Potts Model, a formalism that allows for dynamic, flexible cellular shapes and cell migration. Our simulations show that chemoattraction of T cells enhances the DC scanning efficiency, leading to an increased probability that rare antigen-specific T cells find DCs carrying cognate antigen. Desensitization of T cells after contact with a DC further improves the scanning efficiency, yielding an almost threefold enhancement compared to random migration. Moreover, the chemotaxis-driven migration still roughly appears as a random walk, hence fine-tuned analysis of cell tracks will be required to detect chemotaxis within microscopy data.

  13. Coccidioides Endospores and Spherules Draw Strong Chemotactic, Adhesive, and Phagocytic Responses by Individual Human Neutrophils.

    Directory of Open Access Journals (Sweden)

    Cheng-Yuk Lee

    Full Text Available Coccidioides spp. are dimorphic pathogenic fungi whose parasitic forms cause coccidioidomycosis (Valley fever in mammalian hosts. We use an innovative interdisciplinary approach to analyze one-on-one encounters between human neutrophils and two forms of Coccidioides posadasii. To examine the mechanisms by which the innate immune system coordinates different stages of the host response to fungal pathogens, we dissect the immune-cell response into chemotaxis, adhesion, and phagocytosis. Our single-cell technique reveals a surprisingly strong response by initially quiescent neutrophils to close encounters with C. posadasii, both from a distance (by complement-mediated chemotaxis as well as upon contact (by serum-dependent adhesion and phagocytosis. This response closely resembles neutrophil interactions with Candida albicans and zymosan particles, and is significantly stronger than the neutrophil responses to Cryptococcus neoformans, Aspergillus fumigatus, and Rhizopus oryzae under identical conditions. The vigorous in vitro neutrophil response suggests that C. posadasii evades in vivo recognition by neutrophils through suppression of long-range mobilization and recruitment of the immune cells. This observation elucidates an important paradigm of the recognition of microbes, i.e., that intact immunotaxis comprises an intricate spatiotemporal hierarchy of distinct chemotactic processes. Moreover, in contrast to earlier reports, human neutrophils exhibit vigorous chemotaxis toward, and frustrated phagocytosis of, the large spherules of C. posadasii under physiological-like conditions. Finally, neutrophils from healthy donors and patients with chronic coccidioidomycosis display subtle differences in their responses to antibody-coated beads, even though the patient cells appear to interact normally with C. posadasii endospores.

  14. Granulocyte and monocyte adsorptive apheresis ameliorates sepsis in rats.

    Science.gov (United States)

    Ma, Shuai; Xu, Qingqing; Deng, Bo; Zheng, Yin; Tian, Hongyan; Wang, Li; Ding, Feng

    2017-12-01

    Overwhelming activation of granulocytes and monocytes is central to inflammatory responses during sepsis. Granulocyte and monocyte adsorptive apheresis (GMA) is an extracorporeal leukocyte apheresis device filled with cellulose acetate beads and selectively adsorbs granulocytes and monocytes from the peripheral blood. In this study, septic rats received the GMA treatment for 2 h at 18 h after cecal ligation and puncture. GMA selectively adsorbed activated neutrophils and monocytes from the peripheral blood, reduced serum inflammatory cytokine expression, and seemed to improve organ injuries and animal survival. GMA potentially reduced lung injury by alleviating the infiltration of inflammatory cells and the secretion of cytokines. This study showed that selective granulocyte and monocyte adsorption with cellulose acetate beads might ameliorate cecal ligation and puncture (CLP)-induced sepsis and improve survival and organ function.

  15. Human monocyte differentiation stage affects response to arachidonic acid.

    Science.gov (United States)

    Escobar-Alvarez, Elizabeth; Pelaez, Carlos A; García, Luis F; Rojas, Mauricio

    2010-01-01

    AA-induced cell death mechanisms acting on human monocytes and monocyte-derived macrophages (MDM), U937 promonocytes and PMA-differentiated U937 cells were studied. Arachidonic acid induced apoptosis and necrosis in monocytes and U937 cells but only apoptosis in MDM and U937D cells. AA increased both types of death in Mycobacterium tuberculosis-infected cells and increased the percentage of TNFalpha+ cells and reduced IL-10+ cells. Experiments blocking these cytokines indicated that AA-mediated death was TNFalpha- and IL-10-independent. The differences in AA-mediated cell death could be explained by high ROS, calpain and sPLA-2 production and activity in monocytes. Blocking sPLA-2 in monocytes and treatment with antioxidants favored M. tuberculosis control whereas AA enhanced M. tuberculosis growth in MDM. Such evidence suggested that AA-modulated effector mechanisms depend on mononuclear phagocytes' differentiation stage.

  16. Induction of reactive oxygen intermediates in human monocytes by tumour cells and their role in spontaneous monocyte cytotoxicity

    Science.gov (United States)

    Mytar, B; Siedlar, M; Woloszyn, M; Ruggiero, I; Pryjma, J; Zembala, M

    1999-01-01

    The present study examined the ability of human monocytes to produce reactive oxygen intermediates after a contact with tumour cells. Monocytes generated oxygen radicals, as measured by luminol-enhanced chemiluminescence and superoxide anion production, after stimulation with the tumour, but not with untransformed, cells. The use of specific oxygen radical scavengers and inhibitors, superoxide dismutase, catalase, dimethyl sulphoxide and deferoxamine as well as the myeloperoxidase inhibitor 4-aminobenzoic acid hydrazide, indicated that chemiluminescence was dependent on the production of superoxide anion and hydroxyl radical and the presence of myeloperoxidase. The tumour cell-induced chemiluminescent response of monocytes showed different kinetics from that seen after activation of monocytes with phorbol ester. These results indicate that human monocytes can be directly stimulated by tumour cells for reactive oxygen intermediate production. Spontaneous monocyte-mediated cytotoxicity towards cancer cells was inhibited by superoxide dismutase, catalase, deferoxamine and hydrazide, implicating the role of superoxide anion, hydrogen peroxide, hydroxyl radical and hypohalite. We wish to suggest that so-called ‘spontaneous’ tumoricidal capacity of freshly isolated human monocytes may in fact be an inducible event associated with generation of reactive oxygen intermediates and perhaps other toxic mediators, resulting from a contact of monocytes with tumour cells. © 1999 Cancer Research Campaign PMID:10070862

  17. Characterization of human monocyte activation by a water soluble preparation of Aphanizomenon flos-aquae.

    Science.gov (United States)

    Pugh, N; Pasco, D S

    2001-11-01

    Aphanizomenon flos-aquae (AFA) is a fresh-water microalgae that is consumed as a nutrient-dense food source and for its health-enhancing properties. The current research characterizes the effect of a water soluble preparation from AFA on human monocyte/macrophage function and compares the effect of AFA with responses from known agents that modulate the immune system. At 0.5 pg/ml the AFA extract robustly activated nuclear factor kappa B (NF-kappa B) directed luciferase expression in THP-1 human monocytic cells to levels at 50% of those achieved by maximal concentrations (10 microg/ml) of bacterial lipopolysaccharide (LPS). In addition, the AFA extract substantially increased mRNA levels of interleukin-1beta (IL-1beta) and tumor necrosis factor-alpha (TNF-alpha), and enhanced the DNA binding activity of NF-kappa B. The effects of AFA water soluble preparation were similar to the responses displayed by LPS, but clearly different from responses exhibited by tetradecanoyl phorbol acetate (TPA) and interferon-gamma (INF-gamma). Pretreatment of THP-1 monocytes with factors known to induce hyporesponsiveness suppressed both AFA-dependent and LPS-dependent activation. These results suggest that the macrophage-activating properties of the AFA water soluble preparation are mediated through pathways that are similar to LPS-dependent activation.

  18. Prognostic significance of peripheral monocyte count in patients with extranodal natural killer/T-cell lymphoma.

    Science.gov (United States)

    Huang, Jia-Jia; Li, Ya-Jun; Xia, Yi; Wang, Yu; Wei, Wen-Xiao; Zhu, Ying-Jie; Lin, Tong-Yu; Huang, Hui-Qiang; Jiang, Wen-Qi; Li, Zhi-Ming

    2013-05-03

    Extranodal natural killer/T-cell lymphoma (ENKL) has heterogeneous clinical manifestations and prognosis. This study aims to evaluate the prognostic impact of absolute monocyte count (AMC) in ENKL, and provide some immunologically relevant information for better risk stratification in patients with ENKL. Retrospective data from 163 patients newly diagnosed with ENKL were analyzed. The absolute monocyte count (AMC) at diagnosis was analyzed as continuous and dichotomized variables. Independent prognostic factors of survival were determined by Cox regression analysis. The AMC at diagnosis were related to overall survival (OS) and progression-free survival (PFS) in patients with ENKL. Multivariate analysis identified AMC as independent prognostic factors of survival, independent of International Prognostic Index (IPI) and Korean prognostic index (KPI). The prognostic index incorporating AMC and absolute lymphocyte count (ALC), another surrogate factor of immune status, could be used to stratify all 163 patients with ENKL into different prognostic groups. For patients who received chemotherapy followed by radiotherapy (102 cases), the three AMC/ALC index categories identified patients with significantly different survivals. When superimposed on IPI or KPI categories, the AMC/ALC index was better able to identify high-risk patients in the low-risk IPI or KPI category. The baseline peripheral monocyte count is shown to be an effective prognostic indicator of survival in ENKL patients. The prognostic index related to tumor microenvironment might be helpful to identify high-risk patients with ENKL.

  19. Lactate promotes PGE2 synthesis and gluconeogenesis in monocytes to benefit the growth of inflammation-associated colorectal tumor

    Science.gov (United States)

    Wei, Libin; Zhou, Yuxin; Yao, Jing; Qiao, Chen; Ni, Ting; Guo, Ruichen; Guo, Qinglong; Lu, Na

    2015-01-01

    Reprogramming energy metabolism, such as enhanced glycolysis, is an Achilles' heel in cancer treatment. Most studies have been performed on isolated cancer cells. Here, we studied the energy-transfer mechanism in inflammatory tumor microenvironment. We found that human THP-1 monocytes took up lactate secreted from tumor cells through monocarboxylate transporter 1. In THP-1 monocytes, the oxidation product of lactate, pyruvate competed with the substrate of proline hydroxylase and inhibited its activity, resulting in the stabilization of HIF-1α under normoxia. Mechanistically, activated hypoxia-inducible factor 1-α in THP-1 monocytes promoted the transcriptions of prostaglandin-endoperoxide synthase 2 and phosphoenolpyruvate carboxykinase, which were the key enzyme of prostaglandin E2 synthesis and gluconeogenesis, respectively, and promote the growth of human colon cancer HCT116 cells. Interestingly, lactate could not accelerate the growth of colon cancer directly in vivo. Instead, the human monocytic cells affected by lactate would play critical roles to ‘feed’ the colon cancer cells. Thus, recycling of lactate for glucose regeneration was reported in cancer metabolism. The anabolic metabolism of monocytes in inflammatory tumor microenvironment may be a critical event during tumor development, allowing accelerated tumor growth. PMID:25938544

  20. HIV-1 infection is associated with changes in nuclear receptor transcriptome, pro-inflammatory and lipid profile of monocytes

    Directory of Open Access Journals (Sweden)

    Renga Barbara

    2012-10-01

    Full Text Available Abstract Background Persistent residual immune activation and lipid dysmetabolism are characteristics of HIV positive patients receiving an highly active antiretroviral therapy (HAART. Nuclear Receptors are transcription factors involved in the regulation of immune and metabolic functions through the modulation of gene transcription. The objective of the present study was to investigate for the relative abundance of members of the nuclear receptor family in monocytic cells isolated from HIV positive patients treated or not treated with HAART. Methods Monocytes isolated from peripheral blood mononuclear cells (PBMC were used for analysis of the relative mRNA expressions of FXR, PXR, LXR, VDR, RARα, RXR, PPARα, PPARβ, PPARγ and GR by Real-Time polymerase chain reaction (PCR. The expression of a selected subset of inflammatory and metabolic genes MCP-1, ICAM-1, CD36 and ABCA1 was also measured. Results Monocytes isolated from HIV infected patients expressed an altered pattern of nuclear receptors characterized by a profound reduction in the expressions of FXR, PXR, PPARα, GR, RARα and RXR. Of interest, the deregulated expression of nuclear receptors was not restored under HAART and was linked to an altered expression of genes which supports both an immune activation and altered lipid metabolism in monocytes. Conclusions Altered expression of genes mediating reciprocal regulation of lipid metabolism and immune function in monocytes occurs in HIV. The present findings provide a mechanistic explanation for immune activation and lipid dysmetabolism occurring in HIV infected patients and could lead to the identification of novel potential therapeutic targets.

  1. HIV-1 infection is associated with changes in nuclear receptor transcriptome, pro-inflammatory and lipid profile of monocytes.

    Science.gov (United States)

    Renga, Barbara; Francisci, Daniela; D'Amore, Claudio; Schiaroli, Elisabetta; Carino, Adriana; Baldelli, Franco; Fiorucci, Stefano

    2012-10-29

    Persistent residual immune activation and lipid dysmetabolism are characteristics of HIV positive patients receiving an highly active antiretroviral therapy (HAART). Nuclear Receptors are transcription factors involved in the regulation of immune and metabolic functions through the modulation of gene transcription. The objective of the present study was to investigate for the relative abundance of members of the nuclear receptor family in monocytic cells isolated from HIV positive patients treated or not treated with HAART. Monocytes isolated from peripheral blood mononuclear cells (PBMC) were used for analysis of the relative mRNA expressions of FXR, PXR, LXR, VDR, RARα, RXR, PPARα, PPARβ, PPARγ and GR by Real-Time polymerase chain reaction (PCR). The expression of a selected subset of inflammatory and metabolic genes MCP-1, ICAM-1, CD36 and ABCA1 was also measured. Monocytes isolated from HIV infected patients expressed an altered pattern of nuclear receptors characterized by a profound reduction in the expressions of FXR, PXR, PPARα, GR, RARα and RXR. Of interest, the deregulated expression of nuclear receptors was not restored under HAART and was linked to an altered expression of genes which supports both an immune activation and altered lipid metabolism in monocytes. Altered expression of genes mediating reciprocal regulation of lipid metabolism and immune function in monocytes occurs in HIV. The present findings provide a mechanistic explanation for immune activation and lipid dysmetabolism occurring in HIV infected patients and could lead to the identification of novel potential therapeutic targets.

  2. Cell surface expression and function of the macromolecular C1 complex on the surface of human monocytes

    Directory of Open Access Journals (Sweden)

    Kinga K Hosszu

    2012-03-01

    Full Text Available The synthesis of the subunits of the C1 complex (C1q, C1s, C1r, and its regulator C1 inhibitor (C1-Inh by human monocytes has been previously established. However, surface expression of these molecules by monocytes has not been shown. Using flow cytometry and antigen-capture ELISA, we show here for the first time that, in addition to C1q, PB monocytes and the monocyte-derived U937 cells express C1s and C1r, as well as Factor B and C1-Inh on their surface. C1s and C1r immunoprecipitated with C1q, suggesting that at least some of the C1q on these cells is part of the C1 complex. Furthermore, the C1 complex on U937 cells was able to trigger complement activation via the classical pathway. The presence of C1-Inh may ensure that an unwarranted autoactivation of the C1 complex does not take place. Since C1-Inh closely monitors the activation of the C1 complex in a sterile or infectious inflammatory environment, further elucidation of the role of C1 complex is crucial to dissect its function in monocyte, DC and T cell activities, and its implications in host defense and tolerance.

  3. Stimulation of the Angiotensin II AT2 Receptor is Anti-inflammatory in Human Lipopolysaccharide-Activated Monocytic Cells

    DEFF Research Database (Denmark)

    Menk, Mario; Graw, Jan Adriaan; von Haefen, Clarissa

    2015-01-01

    in these cells. Human monocytic THP-1 and U937 cells were stimulated with lipopolysaccharide (LPS) and the selective AT2 receptor agonist Compound 21 (C21). Expression of pro- and anti-inflammatory cytokines IL-6, IL-10, tumor necrosis factor-α (TNFα), and IL-1β were analyzed on both the transcriptional...... and the translational level over course of time. Treatment with C21 attenuated the expression of TNFα, IL-6, and IL-10 after LPS challenge in both cell lines in a time- and dose-dependent manner. We conclude that selective AT2 receptor stimulation acts anti-inflammatory in human monocytes. Modulation of cytokine......Recently, AT2 receptors have been discovered on the surface of human immunocompetent cells such as monocytes. Data on regulative properties of this receptor on the cellular immune response are poor. We hypothesized that direct stimulation of the AT2 receptor mediates anti-inflammatory responses...

  4. The Effect of Bone Marrow Mesenchymal Stem Cells on Vitamin D3 Induced Monocytic Differentiation of U937 Cells

    OpenAIRE

    Molaeipour, Zahra; Shamsasanjan, karim; Movassaghpour, Ali Akbari; Akbarzadehlaleh, Parvin; Sabaghi, Fatemeh; Saleh, Mahshid

    2016-01-01

    Purpose: Mesenchymal stem cells (MSCs) are key components of the hematopoietic stem cells (HSCs) niche. They control the process of hematopoiesis by secreting regulatory cytokines, growth factors and expression of important cell adhesion molecules for cell-tocell interactions. In this research, we have investigated the effect of bone marrow derived MSCs on monocytic differentiation of U937 cells line.

  5. Constitutive cytoplasmic localization of p21(Waf1/Cip1) affects the apoptotic process in monocytic leukaemia

    NARCIS (Netherlands)

    Schepers, H; Geugien, M; Eggen, BJL; Vellenga, E

    2003-01-01

    In the present study, we analysed the expression and localization of p21(Waf1/Cip1) in normal and malignant haematopoietic cells. We demonstrate that in normal monocytic cells, protein kinase C (PKC)-induced p21 gene activation, which is nuclear factor-kappaB (NF-kappaB) independent, results in pred

  6. Down-regulation of mitogen-activated protein kinases and nuclear factor-κB signaling is involved in rapamycin suppression of TLR2-induced inflammatory response in monocytic THP-1 cells.

    Science.gov (United States)

    Sun, Ruili; Zhang, Yi; Ma, Shijiang; Qi, Hengtian; Wang, Mingyong; Duan, Juhong; Ma, Shujun; Zhu, Xiaofei; Li, Guancheng; Wang, Hui

    2015-10-01

    Tripalmitoyl-S-glycero-Cys-(Lys) 4 (Pam3CSK4) interacted with TLR2 induces inflammatory responses through the mitogen-activated protein kinases (MAPKs) and nuclear factor-κB (NF-κB) signal pathway. Rapamycin can suppress TLR-induced inflammatory responses; however, the detailed molecular mechanism is not fully understood. Here, the mechanism by which rapamycin suppresses TLR2-induced inflammatory responses was investigated. It was found that Pam3CSK4-induced pro-inflammatory cytokines were significantly down-regulated at both the mRNA and protein levels in THP-1 cells pre-treated with various concentrations of rapamycin. Inhibition of phosphatidylinositol 3-kinase/protein kinase-B (PI3K/AKT) signaling did not suppress the expression of pro-inflammatory cytokines, indicating that the immunosuppression mediated by rapamycin in THP1 cells is independent of the PI3K/AKT pathway. RT-PCR showed that Erk and NF-κB signal pathways are related to the production of pro-inflammatory cytokines. Inhibition of Erk or NF-κB signaling significantly down-regulated production of pro-inflammatory cytokines. Additionally, western blot showed that pre-treatment of THP-1 cells with rapamycin down-regulates MAPKs and NF-κB signaling induced by Pam3CSK4 stimulation, suggesting that rapamycin suppresses Pam3CSK4-induced pro-inflammatory cytokines via inhibition of TLR2 signaling. It was concluded that rapamycin suppresses TLR2-induced inflammatory responses by down-regulation of Erk and NF-κB signaling.

  7. Filaria-induced monocyte dysfunction and its reversal following treatment.

    Science.gov (United States)

    Semnani, Roshanak Tolouei; Keiser, Paul B; Coulibaly, Yaya I; Keita, Falaye; Diallo, Abdallah A; Traore, Diakaridia; Diallo, Dapa A; Doumbo, Ogobara K; Traore, Sekou F; Kubofcik, Joseph; Klion, Amy D; Nutman, Thomas B

    2006-08-01

    Monocyte dysfunction in filarial infection has been proposed as one mechanism underlying the diminished antigen-specific T-cell response seen in patent lymphatic filariasis. Cytokine/chemokine production and gene expression in monocytes from filaria-infected patients and uninfected healthy donors were assessed unstimulated and in response to stimulation with Staphylococcus aureus Cowan I bacteria plus gamma interferon both before and 8 months following treatment. Monocytes from filaria-infected individuals were studded with intracellular microfilarial antigens. Furthermore, monocytes from these individuals were less capable of producing interleukin-8 (IL-8), Exodus II, MIP-1alpha, MIP-1beta, and IL-1alpha and preferentially expressed genes involved in apoptosis and adhesion compared with monocytes from uninfected donors. Eight months following treatment with a single dose of ivermectin-albendazole, some of these defects were reversed, with monocyte production of IL-8, IL-1alpha, MIP-1alpha, and IL-10 being comparable to that seen in the uninfected controls. In addition, a marked increase in mRNA expression of genes associated with protein metabolism, particularly heat shock proteins, was seen compared with pretreatment expression. These data suggest that the function and gene expression of monocytes in filaria-infected patients are altered but that this dysfunction is partially reversible following antifilarial treatment.

  8. Distinct functional programming of human fetal and adult monocytes.

    Science.gov (United States)

    Krow-Lucal, Elisabeth R; Kim, Charles C; Burt, Trevor D; McCune, Joseph M

    2014-03-20

    Preterm birth affects 1 out of 9 infants in the United States and is the leading cause of long-term neurologic handicap and infant mortality, accounting for 35% of all infant deaths in 2008. Although cytokines including interferon-γ (IFN-γ), interleukin-10 (IL-10), IL-6, and IL-1 are produced in response to in utero infection and are strongly associated with preterm labor, little is known about how human fetal immune cells respond to these cytokines. We demonstrate that fetal and adult CD14(+)CD16(-) classical monocytes are distinct in terms of basal transcriptional profiles and in phosphorylation of signal transducers and activators of transcription (STATs) in response to cytokines. Fetal monocytes phosphorylate canonical and noncanonical STATs and respond more strongly to IFN-γ, IL-6, and IL-4 than adult monocytes. We demonstrate a higher ratio of SOCS3 to IL-6 receptor in adult monocytes than in fetal monocytes, potentially explaining differences in STAT phosphorylation. Additionally, IFN-γ signaling results in upregulation of antigen presentation and costimulatory machinery in adult, but not fetal, monocytes. These findings represent the first evidence that primary human fetal and adult monocytes are functionally distinct, potentially explaining how these cells respond differentially to cytokines implicated in development, in utero infections, and the pathogenesis of preterm labor.

  9. Altered signaling in systemic juvenile idiopathic arthritis monocytes.

    Science.gov (United States)

    Macaubas, Claudia; Wong, Elizabeth; Zhang, Yujuan; Nguyen, Khoa D; Lee, Justin; Milojevic, Diana; Shenoi, Susan; Stevens, Anne M; Ilowite, Norman; Saper, Vivian; Lee, Tzielan; Mellins, Elizabeth D

    2016-02-01

    Systemic juvenile idiopathic arthritis (sJIA) is characterized by systemic inflammation and arthritis. Monocytes are implicated in sJIA pathogenesis, but their role in disease is unclear. The response of sJIA monocytes to IFN may be dysregulated. We examined intracellular signaling in response to IFN type I (IFNα) and type II (IFNγ) in monocytes during sJIA activity and quiescence, in 2 patient groups. Independent of disease activity, monocytes from Group 1 (collected between 2002 and 2009) showed defective STAT1 phosphorylation downstream of IFNs, and expressed higher transcript levels of SOCS1, an inhibitor of IFN signaling. In the Group 2 (collected between 2011 and 2014), monocytes of patients with recent disease onset were IFNγ hyporesponsive, but in treated, quiescent subjects, monocytes were hyperresponsive to IFNγ. Recent changes in medication in sJIA may alter the IFN hyporesponsiveness. Impaired IFN/pSTAT1 signaling is consistent with skewing of sJIA monocytes away from an M1 phenotype and may contribute to disease pathology.

  10. Whole Blood Activation Results in Enhanced Detection of T Cell and Monocyte Cytokine Production by Flow Cytometry

    Science.gov (United States)

    Sams, Clarence F.; Crucian, Brian E.

    2001-01-01

    TNFa producing monocytes may represent functionally different monocyte subsets with distinct functions. Whole blood culture eliminates the need to purify cell populations prior to culture and may have significant utility for the routine monitoring of the cytokine balances of the peripheral blood T cell and monocyte populations. In addition, there are distinct advantages to performing whole-blood (WB) activation as compared to PBMC activation. These advantages would include retaining all various cell-cell interactions as well as any soluble factors present in serum that influence cell activation. It is likely that the altered cytokine production observed following whole blood culture more accurately represents the in-vivo immune balance.

  11. STAT3 regulates monocyte TNF-alpha production in systemic inflammation caused by cardiac surgery with cardiopulmonary bypass.

    Directory of Open Access Journals (Sweden)

    Petrus R de Jong

    Full Text Available BACKGROUND: Cardiopulmonary bypass (CPB surgery initiates a controlled systemic inflammatory response characterized by a cytokine storm, monocytosis and transient monocyte activation. However, the responsiveness of monocytes to Toll-like receptor (TLR-mediated activation decreases throughout the postoperative course. The purpose of this study was to identify the major signaling pathway involved in plasma-mediated inhibition of LPS-induced tumor necrosis factor (TNF-α production by monocytes. METHODOLOGY/PRINCIPAL FINDINGS: Pediatric patients that underwent CPB-assisted surgical correction of simple congenital heart defects were enrolled (n = 38. Peripheral blood mononuclear cells (PBMC and plasma samples were isolated at consecutive time points. Patient plasma samples were added back to monocytes obtained pre-operatively for ex vivo LPS stimulations and TNF-α and IL-6 production was measured by flow cytometry. LPS-induced p38 mitogen-activated protein kinase (MAPK and nuclear factor (NF-κB activation by patient plasma was assessed by Western blotting. A cell-permeable peptide inhibitor was used to block STAT3 signaling. We found that plasma samples obtained 4 h after surgery, regardless of pre-operative dexamethasone treatment, potently inhibited LPS-induced TNF-α but not IL-6 synthesis by monocytes. This was not associated with attenuation of p38 MAPK activation or IκB-α degradation. However, abrogation of the IL-10/STAT3 pathway restored LPS-induced TNF-α production in the presence of suppressive patient plasma. CONCLUSIONS/SIGNIFICANCE: Our findings suggest that STAT3 signaling plays a crucial role in the downregulation of TNF-α synthesis by human monocytes in the course of systemic inflammation in vivo. Thus, STAT3 might be a potential molecular target for pharmacological intervention in clinical syndromes characterized by systemic inflammation.

  12. CD14-dependent monocyte isolation enhances phagocytosis of listeria monocytogenes by proinflammatory, GM-CSF-derived macrophages.

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    Caroline Neu

    Full Text Available Macrophages are an important line of defence against invading pathogens. Human macrophages derived by different methods were tested for their suitability as models to investigate Listeria monocytogenes (Lm infection and compared to macrophage-like THP-1 cells. Human primary monocytes were isolated by either positive or negative immunomagnetic selection and differentiated in the presence of granulocyte macrophage colony-stimulating factor (GM-CSF or macrophage colony-stimulating factor (M-CSF into pro- or anti-inflammatory macrophages, respectively. Regardless of the isolation method, GM-CSF-derived macrophages (GM-Mφ stained positive for CD206 and M-CSF-derived macrophages (M-Mφ for CD163. THP-1 cells did not express CD206 or CD163 following incubation with PMA, M- or GM-CSF alone or in combination. Upon infection with Lm, all primary macrophages showed good survival at high multiplicities of infection whereas viability of THP-1 was severely reduced even at lower bacterial numbers. M-Mφ generally showed high phagocytosis of Lm. Strikingly, phagocytosis of Lm by GM-Mφ was markedly influenced by the method used for isolation of monocytes. GM-Mφ derived from negatively isolated monocytes showed low phagocytosis of Lm whereas GM-Mφ generated from positively selected monocytes displayed high phagocytosis of Lm. Moreover, incubation with CD14 antibody was sufficient to enhance phagocytosis of Lm by GM-Mφ generated from negatively isolated monocytes. By contrast, non-specific phagocytosis of latex beads by GM-Mφ was not influenced by treatment with CD14 antibody. Furthermore, phagocytosis of Lactococcus lactis, Escherichia coli, human cytomegalovirus and the protozoan parasite Leishmania major by GM-Mφ was not enhanced upon treatment with CD14 antibody indicating that this effect is specific for Lm. Based on these observations, we propose macrophages derived by ex vivo differentiation of negatively selected human primary monocytes as the most

  13. Quantitative modeling of Escherichia coli chemotactic motion in environments varying in space and time.

    Directory of Open Access Journals (Sweden)

    Lili Jiang

    2010-04-01

    Full Text Available Escherichia coli chemotactic motion in spatiotemporally varying environments is studied by using a computational model based on a coarse-grained description of the intracellular signaling pathway dynamics. We find that the cell's chemotaxis drift velocity v(d is a constant in an exponential attractant concentration gradient [L] proportional, variantexp(Gx. v(d depends linearly on the exponential gradient G before it saturates when G is larger than a critical value G(C. We find that G(C is determined by the intracellular adaptation rate k(R with a simple scaling law: G(C infinity k(1/2(R. The linear dependence of v(d on G = d(ln[L]/dx directly demonstrates E. coli's ability in sensing the derivative of the logarithmic attractant concentration. The existence of the limiting gradient G(C and its scaling with k(R are explained by the underlying intracellular adaptation dynamics and the flagellar motor response characteristics. For individual cells, we find that the overall average run length in an exponential gradient is longer than that in a homogeneous environment, which is caused by the constant kinase activity shift (decrease. The forward runs (up the gradient are longer than the backward runs, as expected; and depending on the exact gradient, the (shorter backward runs can be comparable to runs in a spatially homogeneous environment, consistent with previous experiments. In (spatial ligand gradients that also vary in time, the chemotaxis motion is damped as the frequency omega of the time-varying spatial gradient becomes faster than a critical value omega(c, which is controlled by the cell's chemotaxis adaptation rate k(R. Finally, our model, with no adjustable parameters, agrees quantitatively with the classical capillary assay experiments where the attractant concentration changes both in space and time. Our model can thus be used to study E. coli chemotaxis behavior in arbitrary spatiotemporally varying environments. Further experiments are

  14. Colitogenic role of tumour necrosis factor (TNF) receptors in trinitrobenzene sulphonic acid colitis: TNF-R1 ablation does not affect systemic inflammatory response.

    Science.gov (United States)

    Yang, Y; Wang, H; Dou, Y; Wang, Y; Han, G; Wang, Renxi; Wang, L; Guo, R; Xiao, H; Li, X; Shen, B; Shi, Y; Chen, G; Li, Y

    2011-09-01

    Tumour necrosis factor (TNF)-α plays a critical role in the pathogenesis of T helper type 1-mediated colitis such as Crohn's disease. However, the roles of its two receptors in mediating pathology remain largely unknown. In this study, trinitrobenzene sulphonic acid (TNBS) was used to induce colitis in TNF-receptor single or double knock-out (DKO) BALB/c mice and in wild-type counterparts. TNF-R1(-/-) mice had significantly less weight loss, reduced mortality, colon shortening and oedema, colon histological damage and lower levels of colon myeloperoxidase compared with wild-type (WT) BALB/c mice. A similar manifestation was also observed in TNF-R2(-/-) and TNF-R1(-/-) TNF-R2(-/-) (TNF-R DKO) mice. Strikingly, systemic inflammatory response (including splenomegaly and monocyte expansion) was found in WT and TNF-R1(-/-) mice after TNBS, instead of TNF-R2(-/-) and TNF-R DKO mice. Attenuated pathology of colitis in TNF-R1(-/-) or TNF-R2(-/-) mice correlated with lower amounts of interleukin (IL)-6, IL-1β, monocyte chemotactic protein (MCP)-1, IL-12p70 and interferon (IFN)-γ production in the colons. Importantly, ablation of TNF-R1 or TNF-R2 reduced the number of terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick end-labelling (TUNEL)-positive apoptotic epithelial cells in the affected colons compared with WT TNBS-instilled controls, which might be due to the heightened ratio of Bcl-2/Bax and reduced activity of nuclear factor (NF)-κB. These findings suggest that either TNF-R1 or TNF-R2 plays a pathogenic role in the pathology of colitis and TNF signalling via TNF-R1 or TNF-R2 alone is not sufficient for inducing mucosal damage.

  15. Effect of Legionella pneumophila sonicate on killing of Listeria monocytogenes by human polymorphonuclear neutrophils and monocytes

    DEFF Research Database (Denmark)

    Rechnitzer, C; Bangsborg, Jette Marie; Shand, G H

    1993-01-01

    polymorphonuclear neutrophils and monocytes. Preincubation of neutrophils with L. pneumophila sonicate did not affect phagocytosis of L. monocytogenes, whereas Listeria killing was significantly inhibited at sonicate concentrations of 1 and 2 mg/ml. The phenol phase of a phenol-water extraction, containing most...... of the lipopolysaccharide (LPS), had no inhibitory effect on the listericidal activity of neutrophils. Killing of Listeria by monocytes was inhibited in a similar manner. The inhibitory activity was mainly recovered in the sonicate fraction above 100 kDa, suggesting that components organized in larger molecular complexes...... are most likely to represent the inhibitory factors. The inhibitory activity of L. pneumophila sonic extract appears to be related to inhibition of killing mechanisms since uptake of Listeria was not affected by the sonicate. Our observations indicate that as Legionella infection progresses, bacterial...

  16. Exendin-4 improves cardiac function in mice overexpressing monocyte chemoattractant protein-1 in cardiomyocytes.

    Science.gov (United States)

    Younce, Craig W; Niu, Jianli; Ayala, Jennifer; Burmeister, Melissa A; Smith, Layton H; Kolattukudy, Pappachan; Ayala, Julio E

    2014-11-01

    The incretin hormone glucagon-like peptide-1 (Glp1) is cardioprotective in models of ischemia-reperfusion injury, myocardial infarction and gluco/lipotoxicity. Inflammation is a factor in these models, yet it is unknown whether Glp1 receptor (Glp1r) agonists are protective against cardiac inflammation. We tested the hypothesis that the Glp1r agonist Exendin-4 (Ex4) is cardioprotective in mice with cardiac-specific monocyte chemoattractant protein-1 overexpression. These MHC-MCP1 mice exhibit increased cardiac monocyte infiltration, endoplasmic reticulum (ER) stress, apoptosis, fibrosis and left ventricular dysfunction. Ex4 treatment for 8 weeks improved cardiac function and reduced monocyte infiltration, fibrosis and apoptosis in MHC-MCP1 mice. Ex4 enhanced expression of the ER chaperone glucose-regulated protein-78 (GRP78), decreased expression of the pro-apoptotic ER stress marker CCAAT/-enhancer-binding protein homologous protein (CHOP) and increased expression of the ER calcium regulator Sarco/Endoplasmic Reticulum Calcium ATPase-2a (SERCA2a). These findings suggest that the Glp1r is a viable target for treating cardiomyopathies associated with stimulation of pro-inflammatory factors.

  17. Inflammatory gene expression in monocytes of patients with schizophrenia: overlap and difference with bipolar disorder. A study in naturalistically treated patients.

    Science.gov (United States)

    Drexhage, Roosmarijn C; van der Heul-Nieuwenhuijsen, Leonie; Padmos, Roos C; van Beveren, Nico; Cohen, Dan; Versnel, Marjan A; Nolen, Willem A; Drexhage, Hemmo A

    2010-11-01

    Accumulating evidence indicates an activated inflammatory response system as a vulnerability factor for schizophrenia (SZ) and bipolar disorder (BD). We aimed to detect a specific inflammatory monocyte gene expression signature in SZ and compare such signature with our recently described inflammatory monocyte gene signature in BD. A quantitative-polymerase chain reaction (Q-PCR) case-control gene expression study was performed on monocytes of 27 SZ patients and compared to outcomes collected in 56 BD patients (all patients naturalistically treated). For Q-PCR we used nine 'SZ specific genes' (found in whole genome analysis), the 19 BD signature genes (previously found by us) and six recently described autoimmune diabetes inflammatory monocyte genes. Monocytes of SZ patients had (similar to those of BD patients) a high inflammatory set point composed of three subsets of strongly correlating genes characterized by different sets of transcription/MAPK regulating factors. Subset 1A, characterized by ATF3 and DUSP2, and subset 1B, characterized by EGR3 and MXD1, were shared between BD and SZ patients (up-regulated in 67% and 51%, and 34% and 41%, respectively). Subset 2, characterized by PTPN7 and NAB2 was up-regulated in the monocytes of 62% BD, but down-regulated in the monocytes of 48% of SZ patients. Our approach shows that monocytes of SZ and BD patients overlap, but also differ in inflammatory gene expression. Our approach opens new avenues for nosological classifications of psychoses based on the inflammatory state of patients, enabling selection of those patients who might benefit from an anti-inflammatory treatment.

  18. Cancer Cell-derived Exosomes Induce Mitogen-activated Protein Kinase-dependent Monocyte Survival by Transport of Functional Receptor Tyrosine Kinases.

    Science.gov (United States)

    Song, Xiao; Ding, Yanping; Liu, Gang; Yang, Xiao; Zhao, Ruifang; Zhang, Yinlong; Zhao, Xiao; Anderson, Gregory J; Nie, Guangjun

    2016-04-15

    Tumor-associated macrophages (TAM) play pivotal roles in cancer initiation and progression. Monocytes, the precursors of TAMs, normally undergo spontaneous apoptosis within 2 days, but can subsist in the inflammatory tumor microenvironment for continuous survival and generation of sufficient TAMs. The mechanisms underlying tumor-driving monocyte survival remain obscure. Here we report that cancer cell-derived exosomes were crucial mediators for monocyte survival in the inflammatory niche. Analysis of the survival-promoting molecules in monocytes revealed that cancer cell-derived exosomes activated Ras and extracellular signal-regulated kinases in the mitogen-activated protein kinase (MAPK) pathway, resulting in the prevention of caspase cleavage. Phosphorylated receptor tyrosine kinases (RTKs), such as phosphorylated epidermal growth factor receptor (EGFR) and human epidermal growth factor receptor 2 (HER-2), were abundantly expressed in cancer cell-derived exosomes. Knock-out of EGFR or/and HER-2, or alternatively, inhibitors against their phosphorylation significantly disturbed the exosome-mediated activation of the MAPK pathway, inhibition of caspase cleavage, and increase in survival rate in monocytes. Moreover, the deprived survival-stimulating activity of exosomes due to null expression of EGFR and HER-2 could be restored by activation of another RTK, insulin receptor. Overall, our study uncovered a mechanism of tumor-associated monocyte survival and demonstrated that cancer cell-derived exosomes can stimulate the MAPK pathway in monocytes through transport of functional RTKs, leading to inactivation of apoptosis-related caspases. This work provides insights into the long sought question on monocyte survival prior to formation of plentiful TAMs in the tumor microenvironment.

  19. Influence of phthalates on cytokine production in monocytes and macrophages: a systematic review of experimental trials.

    Directory of Open Access Journals (Sweden)

    Juliana Frohnert Hansen

    Full Text Available Phthalates are a group of endocrine disrupting chemicals suspected to influence the immune system. The aim of this systematic review is to summarise the present knowledge on the influence of phthalates on monocyte and macrophage production and secretion of cytokines, an influence which could affect both pro- and anti-inflammatory abilities of these cells.A systematic search was performed in Medline, Embase and Toxline in June 2013, last updated 3rd of August 2014. Criteria used to select studies were described and published beforehand online on Prospero (http://www.crd.york.ac.uk/NIHR_PROSPERO, registration number CRD42013004236. In vivo, ex vivo and in vitro studies investigating the influence of phthalates on cytokine mRNA expression and cytokine secretion in animals and humans were included. A total of 11 reports, containing 12 studies, were found eligible for inclusion. In these, a total of four different phthalate diesters, six primary metabolites (phthalate monoesters and seven different cytokines were investigated. Though all studies varied greatly in study design and species sources, four out of five studies that investigated di-2-ethylhexyl phthalate found an increased tumour necrosis factor-α secretion/production from monocytes or macrophages. A summary of cytokine measurements was not possible since few studies were comparable in study design and due to insufficient reporting of raw data for most of the included studies.Results from this review have suggested that at least one phthalate (di-2-ethylhexyl phthalate has the ability to enhance tumour necrosis factor-α production/secretion from monocytes/macrophages in vitro, but also observed ex vivo. Influence of other phthalates on other cytokines has only been investigated in few studies. Thus, in vitro studies on primary human monocytes/macrophages as well as more in vivo studies are needed to confirm or dispute these findings.

  20. Whole Blood Activation Results in Altered T Cell and Monocyte Cytokine Production Profiles by Flow Cytometry

    Science.gov (United States)

    Crucian, Brian E.; Sams, Clarence F.

    2001-01-01

    monocytes may represent distinct monocyte subsets with unique functions. CONCLUSIONS: Whole blood culture eliminates the need to purify cell populations prior to culture and may have Significant utility for the routine monitoring of the cytokine balances of the peripheral blood T cell and monocyte populations. In addition, there are distinct advantages to performing whole-blood (WB) activation as compared to PBMC activation. These advantages would include retaining all various cell-cell interactions as well as any soluble factors present in serum that influence cell activation. In this study, alterations in cytokine production are demonstrated between whole blood and PBMC activation. It is likely that whole blood activation more accurately represents the in-vivo immune balance than PBMC activation.

  1. Simulation of self-propelled chemotactic bacteria in a stokes flow*

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    Maury B.

    2010-12-01

    Full Text Available We prescrit a method to simulate the motion of self-propelled rigid particles in a twodimensional Stokesian fluid, taking into account chemotactic behaviour. Self-propulsion is modelled as a point force associated to each particle, placed at a certain distance from its gravity centre. The method for solving the fluid flow and the motion of the bacteria is based on a variational formulation on the whole domain, including fluid and particles: rigid motion is enforced by penalizing the strain rate tensor on the rigid domain, while incompressibility is treated by duality. This leads to a minimisation problem over unconstrained functional spaces which cari lie easily implemented from any finite element Stokes solver. In order to ensure robustness, a projection algorithm is used to deal with contacts between particles. The particles are meant to represent bacteria of the Escherichia coli type, which interact with their chemical environment through consumption of nutrients and orientation in some favorable direction. Our mode’ takes into account the interaction with oxygen. An advection-diffusion equation on the oxygen concentration is solved in the fluid domain, with a source term accounting for oxygen consumption by the bacteria. In addition, self-propulsion is deactivated for those particles which cannot consume enough oxygen. Finally, the mode’ includes random changes in the orientation of the individual bacteria, with a frequency that depends on the surrounding oxygen concentration, in order to favor the direction of the concentration gradient and thus to reproduce chemotactic behaviour. Numerical simulations implemented with FreeFem++ are presented. Nous présentons une méthode de simulation du mouvement de particules rigides autopropulsées dans un fluide de Stokes en dimension 2. en prenant en compte leur comportement chimiotactique. L’auto-propulsion est modélisée par une force (presque ponctuelle associée à chaque particule et plac

  2. Functional role of CD11c+ monocytes in atherogenesis associated with hypercholesterolemia

    Science.gov (United States)

    Monocyte activation and migration into the arterial wall are key events in atherogenesis associated with hypercholesterolemia. CD11c/CD18, a beta2 integrin expressed on human monocytes and a subset of mouse monocytes, has been shown to play a distinct role in human monocyte adhesion on endothelial c...

  3. HIV-1-infected monocytes and monocyte-derived macrophages are impaired in their ability to produce superoxide radicals.

    Science.gov (United States)

    Howell, A L; Groveman, D S; Wallace, P K; Fanger, M W

    1997-01-01

    Monocytes and monocyte-derived macrophages play a key role in immune defense against pathogenic organisms. Superoxide anion production is a key mechanism by which phagocytes kill pathogens. We sought to determine whether human immunodeficiency virus-infected monocytes and monocyte-derived macrophages are compromised in their ability to produce the superoxide anion following stimulation with phorbol myristate acetate (PMA) or after cross-linking the type I Fc receptor for IgG (Fc gamma RI). Fc gamma RI was cross-linked by the binding of monoclonal antibody 197, which reacts with an epitope of Fc gamma RI via its Fc region. Monocytes and monocyte-derived macrophages obtained from seronegative donors were infected in vitro with human immunodeficiency virus-1JR-FL and used in effector assays that measured superoxide anion production by the reduction of nitroblue tetrazolium. Reduced nitroblue tetrazolium was measured spectrophotometrically and by microscopy in which the percentage of cells containing intracellular deposits of the dye was assessed. By spectrophotometric measurement, we found that human immunodeficiency virus-infected monocytes and monocyte-derived macrophages produced less superoxide anion following either phorbol myristate acetate stimulation or Fc gamma RI cross-linking than uninfected cells from the same donor. Using microscopy we saw no difference in the percentage of infected and uninfected macrophages containing intracellular deposits of nitroblue tetrazolium suggesting that human immunodeficiency virus-infected macrophages produce less superoxide anion on a per cell basis than uninfected macrophages. Activation of human immunodeficiency virus-infected monocytes with interferon-gamma for 72 h prior to stimulation with phorbol myristate acetate or monoclonal antibody 197 increased their ability to reduce nitroblue tetrazolium. These findings suggest that impairment in the production of reactive oxygen intermediates may, in some cases, contribute to

  4. Effect of cytokines on Siglec-1 and HIV-1 entry in monocyte-derived macrophages: the importance of HIV-1 envelope V1V2 region.

    Science.gov (United States)

    Jobe, Ousman; Trinh, Hung V; Kim, Jiae; Alsalmi, Wadad; Tovanabutra, Sodsai; Ehrenberg, Philip K; Peachman, Kristina K; Gao, Guofen; Thomas, Rasmi; Kim, Jerome H; Michael, Nelson L; Alving, Carl R; Rao, Venigalla B; Rao, Mangala

    2016-06-01

    Monocytes and monocyte-derived macrophages express relatively low levels of CD4. Despite this, macrophages can be effectively infected with human immunodeficiency virus type 1. Macrophages have a critical role in human immunodeficiency virus type 1 transmission; however, the mechanism or mechanisms of virus infection are poorly understood. We report that growth factors, such as granulocyte macrophage colony-stimulating factor and macrophage colony-stimulating factor affect the phenotypic profile and permissiveness of macrophages to human immunodeficiency virus type 1. Human immunodeficiency virus type 1 infection of monocyte-derived macrophages derived from granulocyte macrophage and macrophage colony-stimulating factors was predominantly facilitated by the sialic acid-binding immunoglobulin-like lectin-1. The number of sialic acid-binding immunoglobulin-like lectin receptors on macrophage colony-stimulating factor-derived monocyte-derived macrophages was significantly greater than on granulocyte macrophage colony-stimulating factor-derived monocyte-derived macrophages, and correspondingly, human immunodeficiency virus type 1 infection was greater in the macrophage colony-stimulating factor-derived monocyte-derived macrophages. Single-genome analysis and quantitative reverse transcriptase-polymerase chain reaction revealed that the differences in infectivity was not due to differences in viral fitness or in viral variants with differential infectivity but was due to reduced viral entry into the granulocyte macrophage colony-stimulating factor-derived monocyte-derived macrophages. Anti-sialic acid-binding immunoglobulin-like lectin, trimeric glycoprotein 145, and scaffolded V1V2 proteins were bound to sialic acid-binding immunoglobulin-like lectin and significantly reduced human immunodeficiency virus type 1 entry and infection. Furthermore, sialic acid residues present in the V1V2 region of the envelope protein mediated human immunodeficiency virus type 1

  5. Deciphering the transcriptional circuitry of microRNA genes expressed during human monocytic differentiation

    KAUST Repository

    Schmeier, Sebastian

    2009-12-10

    Background: Macrophages are immune cells involved in various biological processes including host defence, homeostasis, differentiation, and organogenesis. Disruption of macrophage biology has been linked to increased pathogen infection, inflammation and malignant diseases. Differential gene expression observed in monocytic differentiation is primarily regulated by interacting transcription factors (TFs). Current research suggests that microRNAs (miRNAs) degrade and repress translation of mRNA, but also may target genes involved in differentiation. We focus on getting insights into the transcriptional circuitry regulating miRNA genes expressed during monocytic differentiation. Results: We computationally analysed the transcriptional circuitry of miRNA genes during monocytic differentiation using in vitro time-course expression data for TFs and miRNAs. A set of TF?miRNA associations was derived from predicted TF binding sites in promoter regions of miRNA genes. Time-lagged expression correlation analysis was utilised to evaluate the TF?miRNA associations. Our analysis identified 12 TFs that potentially play a central role in regulating miRNAs throughout the differentiation process. Six of these 12 TFs (ATF2, E2F3, HOXA4, NFE2L1, SP3, and YY1) have not previously been described to be important for monocytic differentiation. The remaining six TFs are CEBPB, CREB1, ELK1, NFE2L2, RUNX1, and USF2. For several miRNAs (miR-21, miR-155, miR-424, and miR-17-92), we show how their inferred transcriptional regulation impacts monocytic differentiation. Conclusions: The study demonstrates that miRNAs and their transcriptional regulatory control are integral molecular mechanisms during differentiation. Furthermore, it is the first study to decipher on a large-scale, how miRNAs are controlled by TFs during human monocytic differentiation. Subsequently, we have identified 12 candidate key controllers of miRNAs during this differentiation process. 2009 Schmeier et al; licensee Bio

  6. In vitro inhibitory effects of Moringa oleifera leaf extract and its major components on chemiluminescence and chemotactic activity of phagocytes.

    Science.gov (United States)

    Vongsak, Boonyadist; Gritsanapan, Wandee; Wongkrajang, Yuvadee; Jantan, Ibrahim

    2013-11-01

    The ethanol extract of Moringa oleifera Lam. leaves and its major constituents, crypto-chlorogenic acid, quercetin 3-O-glucoside and kaempferol 3-O-glucoside, were investigated on the respiratory burst of human whole blood and isolated human polymorphonuclear leukocytes (PMNs) using a luminol-based chemiluminescence assay. The chemotactic migration of PMNs was also investigated using the Boyden chamber technique. The ethanol extract demonstrated inhibitory activities on the oxidative burst and the chemotactic migration of PMNs. Quercetin 3-O-glucoside, crypto-chlorogenic acid, and kaempferol 3-O-glucoside, isolated from the extract, expressed relatively strong inhibitory activity on the oxidative burst of PMNs with IC50 values of 4.1, 6.7 and 7.0 microM, respectively, comparable with that of aspirin. They also demonstrated strong inhibition of chemotatic migration of PMNs with IC50 values of 9.5, 15.9 and 18.2 microM, respectively. The results suggest that M. oleifera leaves could modulate the immune response of human phagocytes, linking to its ethnopharmacological use as an anti-inflammatory agent. The immunomodulating activity of the plant was mainly due to its major components.

  7. Monocyte chemiluminescence and macrophage precursors in the aged.

    Directory of Open Access Journals (Sweden)

    Takahashi,Isao

    1985-12-01

    Full Text Available Age-related alterations in the host defense system have been vigorously investigated because of increased susceptibility to infection and neoplasms in the aged. Although monocyte-macrophages form a major part of the cellular defense against microorganisms, the majority of investigations has been limited to neutrophils and lymphocytes. The present study, designed to determine the influence of age on mononuclear phagocytes, revealed no significant decrease in the absolute number of blood monocytes, but did reveal a tendency for the chemiluminescence of blood monocytes to decrease (p less than 0.10 and a significant decrease in the numbers of macrophage precursors (p less than 0.05 in the aged (over 70 year old, in comparison with controls (under 40 years old. On the basis of these findings, functional alterations of monocyte-macrophages seem to participate in the increased susceptibility to infection in the aged.

  8. Two-way communication between endometrial stromal cells and monocytes.

    Science.gov (United States)

    Klinkova, Olga; Hansen, Keith A; Winterton, Emily; Mark, Connie J; Eyster, Kathleen M

    2010-02-01

    Immune system cells and cells of the endometrium have long been proposed to interact in both physiological and pathological processes. The current study was undertaken to examine communication between cultured monocytes and endometrial stromal cells and also to assess responses of endometrial stromal cells for treatment with estradiol (E) in the absence and presence of medroxyprogesterone acetate (P). A telomerase-immortalized human endometrial stromal cell (T-HESC) line and the U937 monocyte cell line were used. Telomerase-immortalized human endometrial stromal cells were treated with E +/- P +/- monocyte conditioned medium; U937 were treated +/- T-HESC conditioned medium. Gene expression in response to treatment was examined by DNA microarray. Bidirectional communication, as demonstrated by changes in gene expression, clearly occurred between U937 monocytes and T-HESC.

  9. Reprogramming of human peripheral blood monocytes to erythroid lineage by blocking of the PU-1 gene expression.

    Science.gov (United States)

    Nouri, Masoumeh; Deezagi, Abdolkhalegh; Ebrahimi, Marzieh

    2016-03-01

    In hematopoietic system development, PU.1 and GATA-1 as lineage-specific transcription factors (TF) are expressed in common myeloid progenitors. The cross antagonism between them ascertains gene expression programs of monocytic and erythroid cells, respectively. This concept in transdifferentiation approaches has not been well considered yet, especially in intralineage conversion systems. To demonstrate whether PU.1 suppression induces monocyte lineage conversion into red blood cells, a combination of three PU.1-specific siRNAs was implemented to knock down PU.1 gene expression and generate the balance in favor of GATA-1 expression to induce erythroid differentiation. For this purpose, monocytes were isolated from human peripheral blood and transfected by PU.1 siRNAs. In transfected monocytes, the rate of PU.1 expression in mRNA level was significantly decreased until 0.38 ± 0.118 when compared to untreated monocytes at 72 h (p value ≤0.05) which resulted in significant overexpression of GATA1 of 16.1 ± 0.343-fold compared to the untreated group (p value ≤0.01). Subsequently, overexpression of hemoglobin (α 13.26 ± 1.34-fold; p value≤0.0001) and β-globin (37.55 ± 16.56-fold; p value≤0.0001) was observed when compared to control groups. The results of western immunoblotting confirm those findings too. While, reduced expression of monocyte, CD14 gene, was observed in qRT-PCR and flow cytometry results. Our results suggest that manipulating the ratio of the two TFs in bifurcation differentiation pathways via applying siRNA technology can possibly change the cells' fate as a safe way for therapeutics application.

  10. Cell culture plastics with immobilized interleukin-4 for monocyte differentiation

    DEFF Research Database (Denmark)

    Hansen, Morten; Hjortø, Gertrud Malene; Met, Ozcan

    2011-01-01

    at similar concentrations to the passive adsorption process, as measured by enzyme-linked immunosorbent assays, and the bound IL-4 did not leak into solution to any measurable extent during cell culture. However, covalently bound IL-4 was incapable of inducing monocyte differentiation. This may be caused...... by IL-4 denaturation or improper epitope presentation induced by the immobilization process, or by biological irresponsiveness of monocytes to IL-4 in immobilized formats....

  11. Maturation and demise of human primary monocytes by carbon nanotubes

    Energy Technology Data Exchange (ETDEWEB)

    De Nicola, Milena, E-mail: milena.de.nicola@uniroma2.it [University of Rome ' Tor Vergata' , Department of Biology (Italy); Mirabile Gattia, Daniele, E-mail: daniele.mirabile@enea.it [UTTMAT, ENEA-C.R. Casaccia (Italy); Traversa, Enrico, E-mail: Enrico.Traversa@kaust.edu.sa [King Abdullah University of Science and Technology (KAUST), Division of Physical Science and Engineering (Saudi Arabia); Ghibelli, Lina, E-mail: ghibelli@uniroma2.it [University of Rome ' Tor Vergata' , Department of Biology (Italy)

    2013-06-15

    The possibility of exploiting carbon nanotubes (CNT) in biomedical practices requires thorough analysis of the chemical or bulk effects they may exert on the immune system, the complex network that recognizes and eliminates foreign particles. In particular, the phagocytosing ability of cells belonging to the monocyte/macrophage lineage may render these immune cells an ideal toxicological target of pristine CNT, which may form aggregates of size exceeding monocyte/macrophage phagocytosing plasticity. To shed light on this issue, we analyzed the effects that pristine multi-walled CNT (MWCNT) without metal or biological impurities exert on survival and activation of freshly explanted human peripheral blood monocytes, analyzing in parallel the non-phagocytosing lymphocytes, and using graphite as control carbon material. MWCNT (diameter 10-50 nm, length up to 10 {mu}m) exert two different toxic effects on mononuclear leukocytes: a minor apoptogenic effect (on lymphocytes > monocytes), and a major, apoptosis-independent effect that exclusively and deeply affect monocyte homeostasis. Analysis of monocyte number, adhesion, redox equilibrium, and the differentiation markers CD14 and CD11b reveals that MWCNT cause the selective disappearance of phagocytosis-competent monocytes by mechanisms related to the presence of large nanoparticle aggregates, suggesting phenomena of bulk toxicity possibly consisting of frustrated phagocytosis. At the same time, MWCNT stimulate adhesion of the phagocytosis-incompetent monocytes, and their differentiation toward a peculiar maturation asset. These observations point out novel mechanisms of CNT toxicity, renewing concerns that they may impair the innate immune system deranging the inflammatory responses.

  12. Lactic acid delays the inflammatory response of human monocytes

    Energy Technology Data Exchange (ETDEWEB)

    Peter, Katrin, E-mail: katrin.peter@ukr.de [Department of Internal Medicine III, University Hospital Regensburg, Franz-Josef-Strauß-Allee 11, 93053 Regensburg (Germany); Rehli, Michael, E-mail: michael.rehli@ukr.de [Department of Internal Medicine III, University Hospital Regensburg, Franz-Josef-Strauß-Allee 11, 93053 Regensburg (Germany); RCI Regensburg Center for Interventional Immunology, University Hospital Regensburg, Franz-Josef-Strauß-Allee 11, 93053 Regensburg (Germany); Singer, Katrin, E-mail: katrin.singer@ukr.de [Department of Internal Medicine III, University Hospital Regensburg, Franz-Josef-Strauß-Allee 11, 93053 Regensburg (Germany); Renner-Sattler, Kathrin, E-mail: kathrin.renner-sattler@ukr.de [Department of Internal Medicine III, University Hospital Regensburg, Franz-Josef-Strauß-Allee 11, 93053 Regensburg (Germany); Kreutz, Marina, E-mail: marina.kreutz@ukr.de [Department of Internal Medicine III, University Hospital Regensburg, Franz-Josef-Strauß-Allee 11, 93053 Regensburg (Germany); RCI Regensburg Center for Interventional Immunology, University Hospital Regensburg, Franz-Josef-Strauß-Allee 11, 93053 Regensburg (Germany)

    2015-02-13

    Lactic acid (LA) accumulates under inflammatory conditions, e.g. in wounds or tumors, and influences local immune cell functions. We previously noted inhibitory effects of LA on glycolysis and TNF secretion of human LPS-stimulated monocytes. Here, we globally analyze the influence of LA on gene expression during monocyte activation. To separate LA-specific from lactate- or pH-effects, monocytes were treated for one or four hours with LPS in the presence of physiological concentrations of LA, sodium lactate (NaL) or acidic pH. Analyses of global gene expression profiles revealed striking effects of LA during the early stimulation phase. Up-regulation of most LPS-induced genes was significantly delayed in the presence of LA, while this inhibitory effect was attenuated in acidified samples and not detected after incubation with NaL. LA targets included genes encoding for important monocyte effector proteins like cytokines (e.g. TNF and IL-23) or chemokines (e.g. CCL2 and CCL7). LA effects were validated for several targets by quantitative RT-PCR and/or ELISA. Further analysis of LPS-signaling pathways revealed that LA delayed the phosphorylation of protein kinase B (AKT) as well as the degradation of IκBα. Consistently, the LPS-induced nuclear accumulation of NFκB was also diminished in response to LA. These results indicate that the broad effect of LA on gene expression and function of human monocytes is at least partially caused by its interference with immediate signal transduction events after activation. This mechanism might contribute to monocyte suppression in the tumor environment. - Highlights: • Lactic acid broadly delays LPS-induced gene expression in human monocytes. • Expression of important monocyte effector molecules is affected by lactic acid. • Interference of lactic acid with TLR signaling causes the delayed gene expression. • The profound effect of lactic acid might contribute to immune suppression in tumors.

  13. Maturation and demise of human primary monocytes by carbon nanotubes

    KAUST Repository

    De Nicola, Milena D.

    2013-05-17

    The possibility of exploiting carbon nanotubes (CNT) in biomedical practices requires thorough analysis of the chemical or bulk effects they may exert on the immune system, the complex network that recognizes and eliminates foreign particles. In particular, the phagocytosing ability of cells belonging to the monocyte/macrophage lineage may render these immune cells an ideal toxicological target of pristine CNT, which may form aggregates of size exceeding monocyte/macrophage phagocytosing plasticity. To shed light on this issue, we analyzed the effects that pristine multi-walled CNT (MWCNT) without metal or biological impurities exert on survival and activation of freshly explanted human peripheral blood monocytes, analyzing in parallel the non-phagocytosing lymphocytes, and using graphite as control carbon material. MWCNT (diameter 10-50 nm, length up to 10 μm) exert two different toxic effects on mononuclear leukocytes: a minor apoptogenic effect (on lymphocytes > monocytes), and a major, apoptosis-independent effect that exclusively and deeply affect monocyte homeostasis. Analysis of monocyte number, adhesion, redox equilibrium, and the differentiation markers CD14 and CD11b reveals that MWCNT cause the selective disappearance of phagocytosis-competent monocytes by mechanisms related to the presence of large nanoparticle aggregates, suggesting phenomena of bulk toxicity possibly consisting of frustrated phagocytosis. At the same time, MWCNT stimulate adhesion of the phagocytosis-incompetent monocytes, and their differentiation toward a peculiar maturation asset. These observations point out novel mechanisms of CNT toxicity, renewing concerns that they may impair the innate immune system deranging the inflammatory responses. © 2013 Springer Science+Business Media Dordrecht.

  14. Proliferative and inflammatory factors in the vitreous of patients with proliferative diabetic retinopathy

    Directory of Open Access Journals (Sweden)

    V V Chernykh

    2015-01-01

    Full Text Available Purpose: The purpose was to measure the concentrations of various cytokines and growth factors (including vascular endothelial growth factor [VEGF] and pigment epithelium-derived factor [PEDF] in the vitreous of patients with proliferative diabetic retinopathy (PDR and to investigate interaction between inflammatory and proliferative factors in the genesis of PDR. Materials and Methods : Vitreous samples from 32 eyes with PDR and 25 eyes without diabetes mellitus and signs of DR (control were collected. Vitreous concentrations of VEGF, PEDF, monocyte chemotactic protein-1 (MCP-1, interleukin-4 (IL-4, IL-6, IL-8, IL-10, IL-17A, and secretory immunoglobulin A (sIgA were simultaneously measured using enzyme-linked immunoassay. Results : Vitreous levels of VEGF, PEDF, IL-17A, IL-6, IL-8, IL-4, and sIgA were significantly (Π < 0.05 higher in eyes with PDR compared to control. The concentration of VEGF was more than 17-times higher than in control, and the concentration of PEDF was not changed oppositely and was also higher (1.45-times compared to control, that may indicate disturbances of compensatory mechanisms in angiogenesis regulation in PDR. Significant (Π < 0.05 positive correlations were observed between vitreous concentrations of VEGF and IL-17ΐ (r = 0.45, VEGF and IL-8 (r = 0.48, VEGF and IL-4 (r = 0.51, PEDF and IL-17ΐ (r = 0.48, PEDF and IL-8 (r = 0.59, MCP-1 and PEDF (r = 0.72, MCP-1 and IL-8 (r0 = 0.45, IL-4 and IL-17ΐ (r = 0.65, IL-4 and IL-8 (r = 0.71, IL-8 and IL-17ΐ (r = 0.59. Conclusions: Significantly raised levels of inflammatory and proliferative factors and numerous positive correlations between them may demonstrate a significant role of activation of vascular proliferation and local inflammation in the pathogenesis of PDR.

  15. Chemotactic Control of the Two Flagellar Systems of Rhodobacter sphaeroides Is Mediated by Different Sets of CheY and FliM Proteins▿ †

    Science.gov (United States)

    del Campo, Ana Martínez; Ballado, Teresa; de la Mora, Javier; Poggio, Sebastian; Camarena, Laura; Dreyfus, Georges

    2007-01-01

    Rhodobacter sphaeroides expresses two different flagellar systems, a subpolar flagellum (fla1) and multiple polar flagella (fla2). These structures are encoded by different sets of flagellar genes. The chemotactic control of the subpolar flagellum (fla1) is mediated by three of the six different CheY proteins (CheY6, CheY4, or CheY3). We show evidence that CheY1, CheY2, and CheY5 control the chemotactic behavior mediated by fla2 flagella and that RSP6099 encodes the fla2 FliM protein. PMID:17890312

  16. Immune surveillance of the lung by migrating tissue monocytes

    Science.gov (United States)

    Rodero, Mathieu P; Poupel, Lucie; Loyher, Pierre-Louis; Hamon, Pauline; Licata, Fabrice; Pessel, Charlotte; Hume, David A; Combadière, Christophe; Boissonnas, Alexandre

    2015-01-01

    Monocytes are phagocytic effector cells in the blood and precursors of resident and inflammatory tissue macrophages. The aim of the current study was to analyse and compare their contribution to innate immune surveillance of the lung in the steady state with macrophage and dendritic cells (DC). ECFP and EGFP transgenic reporters based upon Csf1r and Cx3cr1 distinguish monocytes from resident mononuclear phagocytes. We used these transgenes to study the migratory properties of monocytes and macrophages by functional imaging on explanted lungs. Migratory monocytes were found to be either patrolling within large vessels of the lung or locating at the interface between lung capillaries and alveoli. This spatial organisation gives to monocytes the property to capture fluorescent particles derived from both vascular and airway routes. We conclude that monocytes participate in steady-state surveillance of the lung, in a way that is complementary to resident macrophages and DC, without differentiating into macrophages. DOI: http://dx.doi.org/10.7554/eLife.07847.001 PMID:26167653

  17. Dengue-2 infection and the induction of apoptosis in human primary monocytes

    Directory of Open Access Journals (Sweden)

    Amanda Torrentes-Carvalho

    2009-12-01

    Full Text Available Monocytes/macrophages are important targets for dengue virus (DENV replication; they induce inflammatory mediators and are sources of viral dissemination in the initial phase of the disease. Apoptosis is an active process of cellular destruction genetically regulated, in which a complex enzymatic pathway is activated and may be trigged by many viral infections. Since the mechanisms of apoptotic induction in DENV-infected target cells are not yet defined, we investigated the virus-cell interaction using a model of primary human monocyte infection with DENV-2 with the aim of identifying apoptotic markers. Cultures analyzed by flow cytometry and confocal microscopy yielded DENV antigen positive cells with rates that peaked at the second day post infection (p.i., decayed afterwards and produced the apoptosis-related cytokines TNF-α and IL-10. Phosphatidylserine, an early marker for apoptosis, was increased at the cell surface and the Fas death receptor was upregulated at the second day p.i. at significantly higher rates in DENV infected cell cultures than controls. However, no detectable changes were observed in the expression of the anti-apoptotic protein Bcl-2 in infected cultures. Our data support vir