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Sample records for activation regulated chemokine

  1. Serum thymus and activation-regulated chemokine as disease activity and response biomarker in alopecia areata.

    PubMed

    Inui, Shigeki; Noguchi, Fumihito; Nakajima, Takeshi; Itami, Satoshi

    2013-11-01

    Serum thymus and activation-regulated chemokine/CCL17 (sTARC) is known as a good indicator for atopic dermatitis severity. Herein, we investigate whether sTARC correlates with severity and therapeutic response for alopecia areata (AA) in our 121 patients. The sTARC mean of AA totalis and universalis was significantly higher than mild AA. Next, we compared sTARC of diffuse AA (n = 14) and severity-controlled patchy AA (n = 32) and found that sTARC in diffuse AA (564.2 ± 400.0 pg/mL) was significantly higher than that of the patchy type (344.0 ± 239.8 pg/mL), suggesting a potential role of TARC in active progression of diffuse AA. Ten patients with diffuse AA were treated with i.v. corticosteroid pulse therapy. Then, we tested whether sTARC can predict prognosis after the pulse therapy and found that baseline sTARC in the poor responders (1025.5 ± 484.8 pg/mL) was significantly higher than that in the good responders (complete remission at 24 months after the pulse therapy, 347.8 ± 135.7 pg/mL), indicating sTARC as a response biomarker in the corticosteroid pulse therapy for diffuse AA. Finally, to investigate TARC production in the affected hair follicles, we performed immunohistochemical double staining of TARC and CD68 using scalp skin specimens of diffuse AA with high titers of sTARC. The results showed their co-localization in the infiltrating cells around the AA hair follicles, suggesting that TARC is mainly produced from CD68(+) histiocytes. In conclusion, sTARC is a disease activity and response biomarker in AA, providing new insight beyond the T-helper 1/2 paradigm to solve the immunological pathogenesis of AA.

  2. Novel antiviral activity of chemokines

    SciTech Connect

    Nakayama, Takashi; Shirane, Jumi; Hieshima, Kunio; Shibano, Michiko; Watanabe, Masayasu; Jin, Zhe; Nagakubo, Daisuke; Saito, Takuya; Shimomura, Yoshikazu; Yoshie, Osamu . E-mail: o.yoshie@med.kindai.ac.jp

    2006-07-05

    Antimicrobial peptides are a diverse family of small, mostly cationic polypeptides that kill bacteria, fungi and even some enveloped viruses, while chemokines are a group of mostly cationic small proteins that induce directed migration of leukocytes through interactions with a group of seven transmembrane G protein-coupled receptors. Recent studies have shown that antimicrobial peptides and chemokines have substantially overlapping functions. Thus, while some antimicrobial peptides are chemotactic for leukocytes, some chemokines can kill a wide range of bacteria and fungi. Here, we examined a possible direct antiviral activity of chemokines against an enveloped virus HSV-1. Among 22 human chemokines examined, chemokines such as MIP-1{alpha}/CCL3, MIP-1{beta}/CCL4 and RANTES/CCL5 showed a significant direct antiviral activity against HSV-1. It is intriguing that these chemokines are mostly known to be highly expressed by effector CD8{sup +} T cells. The chemokines with a significant anti-HSV-1 activity commonly bound to HSV-1 virions via envelope glycoprotein gB. Electron microscopy revealed that the chemokines with a significant anti-HSV-1 activity were commonly capable of generating pores in the envelope of HSV-1. Thus, some chemokines have a significant direct antiviral activity against HSV-1 in vitro and may have a potential role in host defense against HSV-1 as a direct antiviral agent.

  3. The chemokine CCL5 regulates glucose uptake and AMP kinase signaling in activated T cells to facilitate chemotaxis.

    PubMed

    Chan, Olivia; Burke, J Daniel; Gao, Darrin F; Fish, Eleanor N

    2012-08-24

    Recruitment of effector T cells to sites of infection or inflammation is essential for an effective adaptive immune response. The chemokine CCL5 (RANTES) activates its cognate receptor, CCR5, to initiate cellular functions, including chemotaxis. In earlier studies, we reported that CCL5-induced CCR5 signaling activates the mTOR/4E-BP1 pathway to directly modulate mRNA translation. Specifically, CCL5-mediated mTOR activation contributes to T cell chemotaxis by initiating the synthesis of chemotaxis-related proteins. Up-regulation of chemotaxis-related proteins may prime T cells for efficient migration. It is now clear that mTOR is also a central regulator of nutrient sensing and glycolysis. Herein we describe a role for CCL5-mediated glucose uptake and ATP accumulation to meet the energy demands of chemotaxis in activated T cells. We provide evidence that CCL5 is able to induce glucose uptake in an mTOR-dependent manner. CCL5 treatment of ex vivo activated human CD3(+) T cells also induced the activation of the nutrient-sensing kinase AMPK and downstream substrates ACC-1, PFKFB-2, and GSK-3β. Using 2-deoxy-d-glucose, an inhibitor of glucose uptake, and compound C, an inhibitor of AMPK, experimental data are presented that demonstrate that CCL5-mediated T cell chemotaxis is dependent on glucose, as these inhibitors inhibit CCL5-mediated chemotaxis in a dose-dependent manner. Altogether, these findings suggest that both glycolysis and AMPK signaling are required for efficient T cell migration in response to CCL5. These studies extend the role of CCL5 mediated CCR5 signaling beyond lymphocyte chemotaxis and demonstrate a role for chemokines in promoting glucose uptake and ATP production to match energy demands of migration.

  4. Cysteine Cathepsins Activate ELR Chemokines and Inactivate Non-ELR Chemokines.

    PubMed

    Repnik, Urska; Starr, Amanda E; Overall, Christopher M; Turk, Boris

    2015-05-29

    Cysteine cathepsins are primarily lysosomal proteases involved in general protein turnover, but they also have specific proteolytic functions in antigen presentation and bone remodeling. Cathepsins are most stable at acidic pH, although growing evidence indicates that they have physiologically relevant activity also at neutral pH. Post-translational proteolytic processing of mature chemokines is a key, yet underappreciated, level of chemokine regulation. Although the role of selected serine proteases and matrix metalloproteases in chemokine processing has long been known, little has been reported about the role of cysteine cathepsins. Here we evaluated cleavage of CXC ELR (CXCL1, -2, -3, -5, and -8) and non-ELR (CXCL9-12) chemokines by cysteine cathepsins B, K, L, and S at neutral pH by high resolution Tris-Tricine SDS-PAGE and matrix-assisted laser desorption ionization time-of-flight mass spectrometry. Whereas cathepsin B cleaved chemokines especially in the C-terminal region, cathepsins K, L, and S cleaved chemokines at the N terminus with glycosaminoglycans modulating cathepsin processing of chemokines. The functional consequences of the cleavages were determined by Ca(2+) mobilization and chemotaxis assays. We show that cysteine cathepsins inactivate and in some cases degrade non-ELR CXC chemokines CXCL9-12. In contrast, cathepsins specifically process ELR CXC chemokines CXCL1, -2, -3, -5, and -8 N-terminally to the ELR motif, thereby generating agonist forms. This study suggests that cysteine cathepsins regulate chemokine activity and thereby leukocyte recruitment during protective or pathological inflammation.

  5. Cysteine Cathepsins Activate ELR Chemokines and Inactivate Non-ELR Chemokines*

    PubMed Central

    Repnik, Urska; Starr, Amanda E.; Overall, Christopher M.; Turk, Boris

    2015-01-01

    Cysteine cathepsins are primarily lysosomal proteases involved in general protein turnover, but they also have specific proteolytic functions in antigen presentation and bone remodeling. Cathepsins are most stable at acidic pH, although growing evidence indicates that they have physiologically relevant activity also at neutral pH. Post-translational proteolytic processing of mature chemokines is a key, yet underappreciated, level of chemokine regulation. Although the role of selected serine proteases and matrix metalloproteases in chemokine processing has long been known, little has been reported about the role of cysteine cathepsins. Here we evaluated cleavage of CXC ELR (CXCL1, -2, -3, -5, and -8) and non-ELR (CXCL9–12) chemokines by cysteine cathepsins B, K, L, and S at neutral pH by high resolution Tris-Tricine SDS-PAGE and matrix-assisted laser desorption ionization time-of-flight mass spectrometry. Whereas cathepsin B cleaved chemokines especially in the C-terminal region, cathepsins K, L, and S cleaved chemokines at the N terminus with glycosaminoglycans modulating cathepsin processing of chemokines. The functional consequences of the cleavages were determined by Ca2+ mobilization and chemotaxis assays. We show that cysteine cathepsins inactivate and in some cases degrade non-ELR CXC chemokines CXCL9–12. In contrast, cathepsins specifically process ELR CXC chemokines CXCL1, -2, -3, -5, and -8 N-terminally to the ELR motif, thereby generating agonist forms. This study suggests that cysteine cathepsins regulate chemokine activity and thereby leukocyte recruitment during protective or pathological inflammation. PMID:25833952

  6. Clinical significance of serum thymus and activation-regulated chemokine in gastric cancer: Potential as a serum biomarker

    PubMed Central

    Lim, Jong-Baeck; Kim, Do-Kyun; Chung, Hye Won

    2014-01-01

    Thymus and activation-regulated chemokine (TARC) can stimulate cancer cell proliferation and migration. The present study evaluated the clinical significance of serum TARC in gastric cancer (GC). We measured serum TARC, macrophage-derived chemokine, monocyte chemotactic protein-1 and stem cell factor (SCF) levels using a chemiluminescent immunoassay along the GC carcinogenesis (normal, high-risk, early GC [EGC] and advanced GC [AGC]) in both training (N = 25 per group) and independent validation datasets (90 normal, 30 high-risk, 50 EGC and 50 AGC). Serum levels were compared among groups using one-way analysis of variance. To evaluate the diagnostic potential of serum TARC for GC, receiver operating characteristic curve and logistic regression analyses were performed. Correlations between serum TARC and GC clinicopathological features were analyzed using Spearman's correlation. In the training dataset, serum TARC correlated with serum MDC, MCP-1 and SCF. However, only serum TARC and SCF were significantly higher in cancer groups than non-cancer groups (P < 0.001). In the validation dataset, serum TARC also increased along the GC carcinogenesis; the AGC group (167.2 ± 111.1 ng/mL) had significantly higher levels than the EGC (109.1 ± 67.7 ng/mL), the high-risk (66.2 ± 47.7 ng/mL) and the normal (67.5 ± 36.2 ng/mL) groups (Bonferroni, all P < 0.001). Receiver operating characteristic curves and logistic regression demonstrated the remarkable diagnostic potential of serum TARC as a single marker (72.0% sensitivity and 71.1% specificity; cutoff point, 0.37; logistic regression) and in a multiple-marker panel (72.6% sensitivity and 88.2% specificity; cutoff point, 0.54). Spearman's correlation showed that serum TARC was closely correlated with tumor size (γs = 0.227, P = 0.028), T-stage (γs = 0.340, P = 0.001), N-stage (γs = 0.318, P = 0.002) and M-stage (γs = 0.346, P = 0.001). Serum TARC is a promising serum biomarker for GC

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

    PubMed

    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)

  8. The Anti-inflammatory Protein TSG-6 Regulates Chemokine Function by Inhibiting Chemokine/Glycosaminoglycan Interactions*

    PubMed Central

    Dyer, Douglas P.; Salanga, Catherina L.; Johns, Scott C.; Valdambrini, Elena; Fuster, Mark M.; Milner, Caroline M.; Day, Anthony J.; Handel, Tracy M.

    2016-01-01

    TNF-stimulated gene-6 (TSG-6) is a multifunctional protein secreted in response to pro-inflammatory stimuli by a wide range of cells, including neutrophils, monocytes, and endothelial cells. It has been shown to mediate anti-inflammatory and protective effects when administered in disease models, in part, by reducing neutrophil infiltration. Human TSG-6 inhibits neutrophil migration by binding CXCL8 through its Link module (Link_TSG6) and interfering with the presentation of CXCL8 on cell-surface glycosaminoglycans (GAGs), an interaction that is vital for the function of many chemokines. TSG-6 was also found to interact with chemokines CXCL11 and CCL5, suggesting the possibility that it may function as a broad specificity chemokine-binding protein, functionally similar to those encoded by viruses. This study was therefore undertaken to explore the ability of TSG-6 to regulate the function of other chemokines. Herein, we demonstrate that Link_TSG6 binds chemokines from both the CXC and CC families, including CXCL4, CXCL12, CCL2, CCL5, CCL7, CCL19, CCL21, and CCL27. We also show that the Link_TSG6-binding sites on chemokines overlap with chemokine GAG-binding sites, and that the affinities of Link_TSG6 for these chemokines (KD values 1–85 nm) broadly correlate with chemokine-GAG affinities. Link_TSG6 also inhibits chemokine presentation on endothelial cells not only through a direct interaction with chemokines but also by binding and therefore masking the availability of GAGs. Along with previous work, these findings suggest that TSG-6 functions as a pluripotent regulator of chemokines by modulating chemokine/GAG interactions, which may be a major mechanism by which TSG-6 produces its anti-inflammatory effects in vivo. PMID:27044744

  9. MicroRNA-155 regulates monocyte chemokine and chemokine receptor expression in Rheumatoid Arthritis

    PubMed Central

    Elmesmari, Aziza; Fraser, Alasdair R.; Wood, Claire; Gilchrist, Derek; Vaughan, Diane; Stewart, Lynn; McSharry, Charles; McInnes, Iain B.

    2016-01-01

    Objective. To test the hypothesis that miR-155 regulates monocyte migratory potential via modulation of chemokine and chemokine receptor expression in RA, and thereby is associated with disease activity. Methods. The miR-155 copy-numbers in monocytes from peripheral blood (PB) of healthy (n = 22), RA (n = 24) and RA SF (n = 11) were assessed by real time-PCR using synthetic miR-155 as a quantitative standard. To evaluate the functional impact of miR-155, human monocytes were transfected with control or miR-155 mimic, and the effect on transcript levels, and production of chemokines was evaluated by Taqman low-density arrays and multiplex assays. A comparative study evaluated constitutive chemokine receptor expression in miR-155−/− and wild-type murine (CD115 + Ly6C + Ly6G−) monocytes. Results. Compared with healthy monocytes, the miR-155 copy-number was higher in RA, peripheral blood (PB) and SF monocytes (PB P < 0.01, and SF P < 0.0001). The miR-155 copy-number in RA PB monocytes was higher in ACPA-positive compared with ACPA-negative patients (P = 0.033) and correlated (95% CI) with DAS28 (ESR), R = 0.728 (0.460, 0.874), and with tender, R = 0.631 (0.306, 0.824) and swollen, R = 0.503 (0.125, 0.753) joint counts. Enforced-expression of miR-155 in RA monocytes stimulated the production of CCL3, CCL4, CCL5 and CCL8; upregulated CCR7 expression; and downregulated CCR2. Conversely, miR155−/− monocytes showed downregulated CCR7 and upregulated CCR2 expression. Conclusion. Given the observed correlations with disease activity, these data provide strong evidence that miR-155 can contribute to RA pathogenesis by regulating chemokine production and pro-inflammatory chemokine receptor expression, thereby promoting inflammatory cell recruitment and retention in the RA synovium. PMID:27411480

  10. Transcriptional regulation of chemokine expression in ovarian cancer.

    PubMed

    Singha, Bipradeb; Gatla, Himavanth R; Vancurova, Ivana

    2015-01-01

    The increased expression of pro-inflammatory and pro-angiogenic chemokines contributes to ovarian cancer progression through the induction of tumor cell proliferation, survival, angiogenesis, and metastasis. The substantial potential of these chemokines to facilitate the progression and metastasis of ovarian cancer underscores the need for their stringent transcriptional regulation. In this Review, we highlight the key mechanisms that regulate the transcription of pro-inflammatory chemokines in ovarian cancer cells, and that have important roles in controlling ovarian cancer progression. We further discuss the potential mechanisms underlying the increased chemokine expression in drug resistance, along with our perspective for future studies. PMID:25790431

  11. Transcriptional regulation of chemokine expression in ovarian cancer.

    PubMed

    Singha, Bipradeb; Gatla, Himavanth R; Vancurova, Ivana

    2015-01-01

    The increased expression of pro-inflammatory and pro-angiogenic chemokines contributes to ovarian cancer progression through the induction of tumor cell proliferation, survival, angiogenesis, and metastasis. The substantial potential of these chemokines to facilitate the progression and metastasis of ovarian cancer underscores the need for their stringent transcriptional regulation. In this Review, we highlight the key mechanisms that regulate the transcription of pro-inflammatory chemokines in ovarian cancer cells, and that have important roles in controlling ovarian cancer progression. We further discuss the potential mechanisms underlying the increased chemokine expression in drug resistance, along with our perspective for future studies.

  12. Transcriptional Regulation of Chemokine Genes: A Link to Pancreatic Islet Inflammation?

    PubMed Central

    Burke, Susan J.; Collier, J. Jason

    2015-01-01

    Enhanced expression of chemotactic cytokines (aka chemokines) within pancreatic islets likely contributes to islet inflammation by regulating the recruitment and activation of various leukocyte populations, including macrophages, neutrophils, and T-lymphocytes. Because of the powerful actions of these chemokines, precise transcriptional control is required. In this review, we highlight what is known about the signals and mechanisms that govern the transcription of genes encoding specific chemokine proteins in pancreatic islet β-cells, which include contributions from the NF-κB and STAT1 pathways. We further discuss increased chemokine expression in pancreatic islets during autoimmune-mediated and obesity-related development of diabetes. PMID:26018641

  13. Surfactant protein D, Club cell protein 16, Pulmonary and activation-regulated chemokine, C-reactive protein, and Fibrinogen biomarker variation in chronic obstructive lung disease.

    PubMed

    Lock-Johansson, Sofie; Vestbo, Jørgen; Sorensen, Grith Lykke

    2014-11-25

    Chronic obstructive pulmonary disease (COPD) is a multifaceted condition that cannot be fully described by the severity of airway obstruction. The limitations of spirometry and clinical history have prompted researchers to investigate a multitude of surrogate biomarkers of disease for the assessment of patients, prediction of risk, and guidance of treatment. The aim of this review is to provide a comprehensive summary of observations for a selection of recently investigated pulmonary inflammatory biomarkers (Surfactant protein D (SP-D), Club cell protein 16 (CC-16), and Pulmonary and activation-regulated chemokine (PARC/CCL-18)) and systemic inflammatory biomarkers (C-reactive protein (CRP) and fibrinogen) with COPD. The relevance of these biomarkers for COPD is discussed in terms of their biological plausibility, their independent association to disease and hard clinical outcomes, their modification by interventions, and whether changes in clinical outcomes are reflected by changes in the biomarker.

  14. Early up-regulation of chemokine expression in fulminant hepatic failure.

    PubMed

    Leifeld, Ludger; Dumoulin, Franz-Ludwig; Purr, Ingvill; Janberg, Katrin; Trautwein, Christian; Wolff, Martin; Manns, Michael Peter; Sauerbruch, Tilman; Spengler, Ulrich

    2003-03-01

    CC-chemokines recruit and activate macrophages and T lymphocytes, the major components of inflammatory infiltrates in fulminant hepatic failure (FHF). To analyse the role of CC-chemokines in the pathogenesis of FHF, this study examined serum levels and intrahepatic expression of MCP-1, MIP-1alpha, MIP-1beta, and RANTES in the livers and sera of patients with FHF and controls by ELISA, immunohistochemistry, and competitive RT-PCR. Serum levels and intrahepatic expression of all chemokines studied in FHF exceeded the levels in chronic liver diseases and normal controls. Distinct patterns of expression of each chemokine were noted on Kupffer cells, sinusoidal endothelial cells, hepatocytes, lymphocytes, and bile ducts. Intrahepatic chemokine expression correlated closely with the extent of infiltration by macrophages and T lymphocytes (r = 0.65-0.95, p < 0.001). The functional relationship between intrahepatic chemokine release and infiltration was confirmed in chemotaxis assays by inhibiting chemotaxis induced by homogenates of liver tissue obtained from FHF patients with neutralizing MCP-1, MIP-1alpha, MIP-1beta, and RANTES antibodies. The time course of CC-chemokine release was studied in the concanavalin A and the galactosamine/LPS mouse models of FHF. In both models, intrahepatic chemokine up-regulation occurred as an early event prior to hepatic infiltration and liver damage. The data indicate that an abundant intrahepatic release of CC-chemokines is an early and pivotal step in the pathogenesis of FHF.

  15. Regulation of inflammatory chemokine receptors on blood T cells associated to the circulating versus liver chemokines in dengue fever.

    PubMed

    de-Oliveira-Pinto, Luzia Maria; Marinho, Cíntia Ferreira; Povoa, Tiago Fajardo; de Azeredo, Elzinandes Leal; de Souza, Luiza Assed; Barbosa, Luiza Damian Ribeiro; Motta-Castro, Ana Rita C; Alves, Ada M B; Ávila, Carlos André Lins; de Souza, Luiz José; da Cunha, Rivaldo Venâncio; Damasco, Paulo Vieira; Paes, Marciano Viana; Kubelka, Claire Fernandes

    2012-01-01

    Little is known about the role of chemokines/chemokines receptors on T cells in natural DENV infection. Patients from DENV-2 and -3- outbreaks were studied prospectively during the acute or convalescent phases. Expression of chemokine receptor and activation markers on lymphocyte subpopulations were determined by flow cytometry analysis, plasma chemokine ligands concentrations were measured by ELISA and quantification of CCL5/RANTES(+) cells in liver tissues from fatal dengue cases was performed by immunochemistry. In the acute DENV-infection, T-helper/T-cytotoxic type-1 cell (Th1/Tc1)-related CCR5 is significantly higher expressed on both CD4 and CD8 T cells. The Th1-related CXCR3 is up-regulated among CD4 T cells and Tc2-related CCR4 is up-regulated among CD8 T cells. In the convalescent phase, all chemokine receptor or chemokine ligand expression tends to reestablish control healthy levels. Increased CCL2/MCP-1 and CCL4/MIP-1β but decreased CCL5/RANTES levels were observed in DENV-patients during acute infection. Moreover, we showed an increased CD107a expression on CCR5 or CXCR3-expressing T cells and higher expression of CD29, CD44(HIGH) and CD127(LOW) markers on CCR4-expressing CD8 T cells in DENV-patients when compared to controls. Finally, liver from dengue fatal patients showed increased number of cells expressing CCL5/RANTES in three out of four cases compared to three death from a non-dengue patient. In conclusion, both Th1-related CCR5 and CXCR3 among CD4 T cells have a potential ability to exert cytotoxicity function. Moreover, Tc1-related CCR5 and Tc2-related CCR4 among CD8 T cells have a potential ability to exert effector function and migration based on cell markers evaluated. The CCR5 expression would be promoting an enhanced T cell recruitment into liver, a hypothesis that is corroborated by the CCL5/RANTES increase detected in hepatic tissue from dengue fatal cases. The balance between protective and pathogenic immune response mediated by

  16. Regulation of Inflammatory Chemokine Receptors on Blood T Cells Associated to the Circulating Versus Liver Chemokines in Dengue Fever

    PubMed Central

    Povoa, Tiago Fajardo; de Azeredo, Elzinandes Leal; de Souza, Luiza Assed; Barbosa, Luiza Damian Ribeiro; Motta-Castro, Ana Rita C.; Alves, Ada M. B.; Ávila, Carlos André Lins; de Souza, Luiz José; da Cunha, Rivaldo Venâncio; Damasco, Paulo Vieira; Paes, Marciano Viana; Kubelka, Claire Fernandes

    2012-01-01

    Little is known about the role of chemokines/chemokines receptors on T cells in natural DENV infection. Patients from DENV-2 and -3- outbreaks were studied prospectively during the acute or convalescent phases. Expression of chemokine receptor and activation markers on lymphocyte subpopulations were determined by flow cytometry analysis, plasma chemokine ligands concentrations were measured by ELISA and quantification of CCL5/RANTES+ cells in liver tissues from fatal dengue cases was performed by immunochemistry. In the acute DENV-infection, T-helper/T-cytotoxic type-1 cell (Th1/Tc1)-related CCR5 is significantly higher expressed on both CD4 and CD8 T cells. The Th1-related CXCR3 is up-regulated among CD4 T cells and Tc2-related CCR4 is up-regulated among CD8 T cells. In the convalescent phase, all chemokine receptor or chemokine ligand expression tends to reestablish control healthy levels. Increased CCL2/MCP-1 and CCL4/MIP-1β but decreased CCL5/RANTES levels were observed in DENV-patients during acute infection. Moreover, we showed an increased CD107a expression on CCR5 or CXCR3-expressing T cells and higher expression of CD29, CD44HIGH and CD127LOW markers on CCR4-expressing CD8 T cells in DENV-patients when compared to controls. Finally, liver from dengue fatal patients showed increased number of cells expressing CCL5/RANTES in three out of four cases compared to three death from a non-dengue patient. In conclusion, both Th1-related CCR5 and CXCR3 among CD4 T cells have a potential ability to exert cytotoxicity function. Moreover, Tc1-related CCR5 and Tc2-related CCR4 among CD8 T cells have a potential ability to exert effector function and migration based on cell markers evaluated. The CCR5 expression would be promoting an enhanced T cell recruitment into liver, a hypothesis that is corroborated by the CCL5/RANTES increase detected in hepatic tissue from dengue fatal cases. The balance between protective and pathogenic immune response mediated by chemokines

  17. CD26/dipeptidylpeptidase IV-chemokine interactions: double-edged regulation of inflammation and tumor biology.

    PubMed

    Mortier, Anneleen; Gouwy, Mieke; Van Damme, Jo; Proost, Paul; Struyf, Sofie

    2016-06-01

    Post-translational modification of chemokines is an essential regulatory mechanism to enhance or dampen the inflammatory response. CD26/dipeptidylpeptidase IV, ubiquitously expressed in tissues and blood, removes NH2-terminal dipeptides from proteins with a penultimate Pro or Ala. A large number of human chemokines, including CXCL2, CXCL6, CXCL9, CXCL10, CXCL11, CXCL12, CCL3L1, CCL4, CCL5, CCL11, CCL14, and CCL22, are cleaved by CD26; however, the efficiency is clearly influenced by the amino acids surrounding the cleavage site and although not yet proven, potentially affected by the chemokine concentration and interactions with third molecules. NH2-terminal cleavage of chemokines by CD26 has prominent effects on their receptor binding, signaling, and hence, in vitro and in vivo biologic activities. However, rather than having a similar result, the outcome of NH2-terminal truncation is highly diverse. Either no difference in activity or drastic alterations in receptor recognition/specificity and hence, chemotactic activity are observed. Analogously, chemokine-dependent inhibition of HIV infection is enhanced (for CCL3L1 and CCL5) or decreased (for CXCL12) by CD26 cleavage. The occurrence of CD26-processed chemokine isoforms in plasma underscores the importance of the in vitro-observed CD26 cleavages. Through modulation of chemokine activity, CD26 regulates leukocyte/tumor cell migration and progenitor cell release from the bone marrow, as shown by use of mice treated with CD26 inhibitors or CD26 knockout mice. As chemokine processing by CD26 has a significant impact on physiologic and pathologic processes, application of CD26 inhibitors to affect chemokine function is currently explored, e.g., as add-on therapy in viral infection and cancer. PMID:26744452

  18. Chemokine (C-X-C Motif) Receptor 4 and Atypical Chemokine Receptor 3 Regulate Vascular α1-Adrenergic Receptor Function

    PubMed Central

    Bach, Harold H; Wong, Yee M; Tripathi, Abhishek; Nevins, Amanda M; Gamelli, Richard L; Volkman, Brian F; Byron, Kenneth L; Majetschak, Matthias

    2014-01-01

    Chemokine (C-X-C motif) receptor (CXCR) 4 and atypical chemokine receptor (ACKR) 3 ligands have been reported to modulate cardiovascular function in various disease models. The underlying mechanisms, however, remain unknown. Thus, it was the aim of the present study to determine how pharmacological modulation of CXCR4 and ACKR3 regulate cardiovascular function. In vivo administration of TC14012, a CXCR4 antagonist and ACKR3 agonist, caused cardiovascular collapse in normal animals. During the cardiovascular stress response to hemorrhagic shock, ubiquitin, a CXCR4 agonist, stabilized blood pressure, whereas coactivation of CXCR4 and ACKR3 with CXC chemokine ligand 12 (CXCL12), or blockade of CXCR4 with AMD3100 showed opposite effects. While CXCR4 and ACKR3 ligands did not affect myocardial function, they selectively altered vascular reactivity upon α1-adrenergic receptor (AR) activation in pressure myography experiments. CXCR4 activation with ubiquitin enhanced α1-AR-mediated vasoconstriction, whereas ACKR3 activation with various natural and synthetic ligands antagonized α1-AR-mediated vasoconstriction. The opposing effects of CXCR4 and ACKR3 activation by CXCL12 could be dissected pharmacologically. CXCR4 and ACKR3 ligands did not affect vasoconstriction upon activation of voltage-operated Ca2+ channels or endothelin receptors. Effects of CXCR4 and ACKR3 agonists on vascular α1-AR responsiveness were independent of the endothelium. These findings suggest that CXCR4 and ACKR3 modulate α1-AR reactivity in vascular smooth muscle and regulate hemodynamics in normal and pathological conditions. Our observations point toward CXCR4 and ACKR3 as new pharmacological targets to control vasoreactivity and blood pressure. PMID:25032954

  19. Functional inactivation of CXC chemokine receptor 4-mediated responses through SOCS3 up-regulation.

    PubMed

    Soriano, Silvia F; Hernanz-Falcón, Patricia; Rodríguez-Frade, José Miguel; De Ana, Ana Martín; Garzón, Ruth; Carvalho-Pinto, Carla; Vila-Coro, Antonio J; Zaballos, Angel; Balomenos, Dimitrios; Martínez-A, Carlos; Mellado, Mario

    2002-08-01

    Hematopoietic cell growth, differentiation, and chemotactic responses require coordinated action between cytokines and chemokines. Cytokines promote receptor oligomerization, followed by Janus kinase (JAK) kinase activation, signal transducers and transactivators of transcription (STAT) nuclear translocation, and transcription of cytokine-responsive genes. These include genes that encode a family of negative regulators of cytokine signaling, the suppressors of cytokine signaling (SOCS) proteins. After binding their specific receptors, chemokines trigger receptor dimerization and activate the JAK/STAT pathway. We show that SOCS3 overexpression or up-regulation, stimulated by a cytokine such as growth hormone, impairs the response to CXCL12, measured by Ca(2+) flux and chemotaxis in vitro and in vivo. This effect is mediated by SOCS3 binding to the CXC chemokine receptor 4 receptor, blocking JAK/STAT and Galpha(i) pathways, without interfering with cell surface chemokine receptor expression. The data provide clear evidence for signaling cross-talk between cytokine and chemokine responses in building a functional immune system.

  20. Tropoelastin regulates chemokine expression in fibroblasts in Costello syndrome

    SciTech Connect

    Tatano, Yutaka; Fujinawa, Reiko; Kozutsumi, Yasunori; Takahashi, Tsutomu; Tsuji, Daisuke; Takeuchi, Naohiro; Tsuta, Kohji; Takada, Goro; Sakuraba, Hitoshi; Itoh, Kohji

    2008-08-08

    Costello syndrome is a multiple congenital anomaly associated with growth and mental retardation, cardiac and skeletal anomalies, and a predisposition to develop neoplasia. Comprehensive expression analysis revealed remarkable up-regulation of several cytokines and chemokines including Gro family proteins, interleukin-1{beta} (IL-1{beta}), IL-8 and MCP-1 but down-regulation of extracellular matrix components including collagens and proteoglycans of skin fibroblasts derived from a Japanese Costello syndrome patient characterized by significantly reduced tropoelastin mRNA, impaired elastogenesis and enhanced cell proliferation. In contrast, decreases in these chemokines and IL-1{beta} expression were observed in Costello fibroblastic cell lines stably expressing the bovine tropoelastin (btEln) gene and in restored elastic fibers. These results strongly suggest that the human TE gene (ELN) transfer could be applicable for the gene therapy of a group of Costello syndrome patients with reduced ELN gene expression.

  1. Platelet-Derived CCL5 Regulates CXC Chemokine Formation and Neutrophil Recruitment in Acute Experimental Colitis.

    PubMed

    Yu, Changhui; Zhang, Songen; Wang, Yongzhi; Zhang, Su; Luo, Lingtao; Thorlacius, Henrik

    2016-02-01

    Accumulating data suggest that platelets not only regulate thrombosis and haemostasis but also inflammatory processes. Platelets contain numerous potent pro-inflammatory compounds, including the chemokines CCL5 and CXCL4, although their role in acute colitis remains elusive. The aim of this study is to examine the role of platelets and platelet-derived chemokines in acute colitis. Acute colitis is induced in female Balb/c mice by administration of 5% dextran sodium sulfate (DSS) for 5 days. Animals receive a platelet-depleting, anti-CCL5, anti-CXCL4, or a control antibody prior to DSS challenge. Colonic tissue is collected for quantification of myeloperoxidase (MPO) activity, CXCL5, CXCL2, interleukin-6 (IL-6), and CCL5 levels as well as morphological analyses. Platelet depletion reduce tissue damage and clinical disease activity index in DSS-exposed animals. Platelet depletion not only reduces levels of CXCL2 and CXCL5 but also levels of CCL5 in the inflamed colon. Immunoneutralization of CCL5 but not CXCL4 reduces tissue damage, CXC chemokine expression, and neutrophil recruitment in DSS-treated animals. These findings show that platelets play a key role in acute colitis by regulating CXC chemokine generation, neutrophil infiltration, and tissue damage in the colon. Moreover, our results suggest that platelet-derived CCL5 is an important link between platelet activation and neutrophil recruitment in acute colitis.

  2. Chemokine receptor CXCR2: physiology regulator and neuroinflammation controller?

    PubMed Central

    Veenstra, Mike; Ransohoff, Richard M.

    2012-01-01

    The innate immune system is a crucial component of inflammatory reactions, while the central nervous system (CNS) is the most vulnerable site of the body to inflammatory tissue injury. Neuroinflammatory brain pathologies are disorders in which the CNS is threatened by its own immune system. Chemokine receptor CXCR2 and its ligands have been implicated in several neuroinflammatory brain pathologies, as well as in neutrophil recruitment and in the developmental positioning of neural cells. This review focuses on the basics of CXCR2, its regulating role in bone marrow neutrophil recruitment, oligodendrocyte progenitor cell positioning and neural repair mechanisms, as well as its diverse roles in neuroinflammatory brain pathologies. PMID:22445294

  3. Simultaneous Activation of Induced Heterodimerization between CXCR4 Chemokine Receptor and Cannabinoid Receptor 2 (CB2) Reveals a Mechanism for Regulation of Tumor Progression.

    PubMed

    Coke, Christopher J; Scarlett, Kisha A; Chetram, Mahandranauth A; Jones, Kia J; Sandifer, Brittney J; Davis, Ahriea S; Marcus, Adam I; Hinton, Cimona V

    2016-05-01

    The G-protein-coupled chemokine receptor CXCR4 generates signals that lead to cell migration, cell proliferation, and other survival mechanisms that result in the metastatic spread of primary tumor cells to distal organs. Numerous studies have demonstrated that CXCR4 can form homodimers or can heterodimerize with other G-protein-coupled receptors to form receptor complexes that can amplify or decrease the signaling capacity of each individual receptor. Using biophysical and biochemical approaches, we found that CXCR4 can form an induced heterodimer with cannabinoid receptor 2 (CB2) in human breast and prostate cancer cells. Simultaneous, agonist-dependent activation of CXCR4 and CB2 resulted in reduced CXCR4-mediated expression of phosphorylated ERK1/2 and ultimately reduced cancer cell functions such as calcium mobilization and cellular chemotaxis. Given that treatment with cannabinoids has been shown to reduce invasiveness of cancer cells as well as CXCR4-mediated migration of immune cells, it is plausible that CXCR4 signaling can be silenced through a physical heterodimeric association with CB2, thereby inhibiting subsequent functions of CXCR4. Taken together, the data illustrate a mechanism by which the cannabinoid system can negatively modulate CXCR4 receptor function and perhaps tumor progression. PMID:26841863

  4. A Subset of Patients with Acute Myeloid Leukemia Has Leukemia Cells Characterized by Chemokine Responsiveness and Altered Expression of Transcriptional as well as Angiogenic Regulators

    PubMed Central

    Brenner, Annette K.; Reikvam, Håkon; Bruserud, Øystein

    2016-01-01

    Acute myeloid leukemia (AML) is an aggressive and heterogeneous bone marrow malignancy, the only curative treatment being intensive chemotherapy eventually in combination with allogeneic stem cell transplantation. Both the AML and their neighboring stromal cells show constitutive chemokine release, but chemokines seem to function as regulators of AML cell proliferation only for a subset of patients. Chemokine targeting is therefore considered not only for immunosuppression in allotransplanted patients but also as a possible antileukemic strategy in combination with intensive chemotherapy or as part of disease-stabilizing treatment at least for the subset of patients with chemokine-responsive AML cells. In this study, we characterized more in detail the leukemia cell phenotype of the chemokine-responsive patients. We investigated primary AML cells derived from 79 unselected patients. Standardized in vitro suspension cultures were used to investigate AML cell proliferation, and global gene expression profiles were compared for chemokine responders and non-responders identified through the proliferation assays. CCL28-induced growth modulation was used as marker of chemokine responsiveness, and 38 patients were then classified as chemokine-responsive. The effects of exogenous CCL28 (growth inhibition/enhancement/no effect) thus differed among patients and was also dependent on the presence of exogenous hematopoietic growth factors as well as constitutive AML cell cytokine release. The effect of CCR1 inhibition in the presence of chemokine-secreting mesenchymal stem cells also differed among patients. Chemokine-responsive AML cells showed altered expression of genes important for (i) epigenetic transcriptional regulation, particularly lysine acetylation; (ii) helicase activity, especially DExD/H RNA helicases; and (iii) angioregulatory proteins important for integrin binding. Thus, chemokine responsiveness is part of a complex AML cell phenotype with regard to

  5. Regulation of pulmonary fibrosis by chemokine receptor CXCR3

    PubMed Central

    Jiang, Dianhua; Liang, Jiurong; Hodge, Jennifer; Lu, Bao; Zhu, Zhou; Yu, Shuang; Fan, Juan; Gao, Yunfei; Yin, Zhinan; Homer, Robert; Gerard, Craig; Noble, Paul W.

    2004-01-01

    CXC chemokine receptor 3 (CXCR3) is the receptor for the IFN-γ–inducible C-X-C chemokines MIG/CXCL9, IP-10/CXCL10, and I-TAC/CXCL11. CXCR3 is expressed on activated immune cells and proliferating endothelial cells. The role of CXCR3 in fibroproliferation has not been investigated. We examined the role of CXCR3 in pulmonary injury and repair in vivo. CXCR3-deficient mice demonstrated increased mortality with progressive interstitial fibrosis relative to WT mice. Increased fibrosis occurred without increased inflammatory cell recruitment. CXCR3 deficiency resulted in both a reduced early burst of IFN-γ production and decreased expression of CXCL10 after lung injury. We identified a relative deficiency in lung NK cells in the unchallenged CXCR3-deficient lung and demonstrated production of IFN-γ by WT lung NK cells in vivo following lung injury. The fibrotic phenotype in the CXCR3-deficient mice was significantly reversed following administration of exogenous IFN-γ or restoration of endogenous IFN-γ production by adoptive transfer of WT lymph node and spleen cells. Finally, pretreatment of WT mice with IFN-γ–neutralizing Ab’s enhanced fibrosis following lung injury. These data demonstrate a nonredundant role for CXCR3 in limiting tissue fibroproliferation and suggest that this effect may be mediated, in part, by the innate production of IFN-γ following lung injury. PMID:15254596

  6. Regulation of Motor Function and Behavior by Atypical Chemokine Receptor 1

    PubMed Central

    Schneider, Erich H.; Fowler, Stephen C.; Lionakis, Michail S.; Swamydas, Muthulekha; Holmes, Gibran; Diaz, Vivian; Munasinghe, Jeeva; Peiper, Stephen C.; Gao, Ji-Liang; Murphy, Philip M.

    2016-01-01

    Atypical Chemokine Receptor 1 (ACKR1), previously known as the Duffy Antigen Receptor for Chemokines, stands out among chemokine receptors for its high selective expression on Purkinje cells of the cerebellum, consistent with the ability of ACKR1 ligands to activate Purkinje cells in vitro. Nevertheless, evidence for ACKR1 regulation of brain function in vivo has been lacking. Here we demonstrate that Ackr1−/− mice have markedly impaired balance and ataxia when placed on a rotating rod and increased tremor when injected with harmaline, a drug that induces whole-body tremor by activating Purkinje cells. Ackr1−/− mice also exhibited impaired exploratory behavior, increased anxiety-like behavior and frequent episodes of marked hypoactivity under low-stress conditions. The behavioral phenotype of Ackr1−/− mice was the opposite of the phenotype occurring in mice with cerebellar degeneration and the defects persisted when Ackr1 was deficient only on non-hematopoietic cells. We conclude that normal motor function and behavior depend in part on negative regulation of Purkinje cell activity by Ackr1. PMID:24997773

  7. IL-1β reciprocally regulates chemokine and insulin secretion in pancreatic β-cells via NF-κB.

    PubMed

    Burke, Susan J; Stadler, Krisztian; Lu, Danhong; Gleason, Evanna; Han, Anna; Donohoe, Dallas R; Rogers, Richard C; Hermann, Gerlinda E; Karlstad, Michael D; Collier, J Jason

    2015-10-15

    Proinflammatory cytokines impact islet β-cell mass and function by altering the transcriptional activity within pancreatic β-cells, producing increases in intracellular nitric oxide abundance and the synthesis and secretion of immunomodulatory proteins such as chemokines. Herein, we report that IL-1β, a major mediator of inflammatory responses associated with diabetes development, coordinately and reciprocally regulates chemokine and insulin secretion. We discovered that NF-κB controls the increase in chemokine transcription and secretion as well as the decrease in both insulin secretion and proliferation in response to IL-1β. Nitric oxide production, which is markedly elevated in pancreatic β-cells exposed to IL-1β, is a negative regulator of both glucose-stimulated insulin secretion and glucose-induced increases in intracellular calcium levels. By contrast, the IL-1β-mediated production of the chemokines CCL2 and CCL20 was not influenced by either nitric oxide levels or glucose concentration. Instead, the synthesis and secretion of CCL2 and CCL20 in response to IL-1β were dependent on NF-κB transcriptional activity. We conclude that IL-1β-induced transcriptional reprogramming via NF-κB reciprocally regulates chemokine and insulin secretion while also negatively regulating β-cell proliferation. These findings are consistent with NF-κB as a major regulatory node controlling inflammation-associated alterations in islet β-cell function and mass. PMID:26306596

  8. Atypical chemokine receptors in cancer: friends or foes?

    PubMed

    Massara, Matteo; Bonavita, Ornella; Mantovani, Alberto; Locati, Massimo; Bonecchi, Raffaella

    2016-06-01

    The chemokine system is a fundamental component of cancer-related inflammation involved in all stages of cancer development. It controls not only leukocyte infiltration in primary tumors but also angiogenesis, cancer cell proliferation, and migration to metastatic sites. Atypical chemokine receptors are a new, emerging class of regulators of the chemokine system. They control chemokine bioavailability by scavenging, transporting, or storing chemokines. They can also regulate the activity of canonical chemokine receptors with which they share the ligands by forming heterodimers or by modulating their expression levels or signaling activity. Here, we summarize recent results about the role of these receptors (atypical chemokine receptor 1/Duffy antigen receptor for chemokine, atypical chemokine receptor 2/D6, atypical chemokine receptor 3/CXC-chemokine receptor 7, and atypical chemokine receptor 4/CC-chemokine receptor-like 1) on the tumorigenesis process, indicating that their effects are strictly dependent on the cell type on which they are expressed and on their coexpression with other chemokine receptors. Indeed, atypical chemokine receptors inhibit tumor growth and progression through their activity as negative regulators of chemokine bioavailability, whereas, on the contrary, they can promote tumorigenesis when they regulate the signaling of other chemokine receptors, such as CXC-chemokine receptor 4. Thus, atypical chemokine receptors are key components of the regulatory network of inflammation and immunity in cancer and may have a major effect on anti-inflammatory and immunotherapeutic strategies. PMID:26908826

  9. Critical roles of chemokine receptor CCR5 in regulating glioblastoma proliferation and invasion.

    PubMed

    Zhao, Lanfu; Wang, Yuan; Xue, Yafei; Lv, Wenhai; Zhang, Yufu; He, Shiming

    2015-11-01

    Glioblastoma (GBM) is the most prevalent malignant primary brain tumor in adults and exhibits a spectrum of aberrantly aggressive phenotype. Tumor cell proliferation and invasion are critically regulated by chemokines and their receptors. Recent studies have shown that the chemokine CCL5 and its receptor CCR5 play important roles in tumor invasion and metastasis. Nonetheless, the roles of the CCR5 in GBM still remain unclear. The present study provides the evidence that the chemokine receptor CCR5 is highly expressed and associated with poor prognosis in human GBM. Mechanistically, CCL5-CCR5 mediates activation of Akt, and subsequently induces proliferation and invasive responses in U87 and U251 cells. Moreover, down-regulation of CCR5 significantly inhibited the growth of glioma in U87 tumor xenograft mouse model. Finally, high CCR5 expression in GBM is correlated with increased p-Akt expression in patient samples. Together, these findings suggest that the CCR5 is a critical molecular event associated with gliomagenesis.

  10. Schistosoma mansoni secretes a chemokine binding protein with antiinflammatory activity.

    PubMed

    Smith, Philip; Fallon, Rosie E; Mangan, Niamh E; Walsh, Caitriona M; Saraiva, Margarida; Sayers, Jon R; McKenzie, Andrew N J; Alcami, Antonio; Fallon, Padraic G

    2005-11-21

    The coevolution of humans and infectious agents has exerted selective pressure on the immune system to control potentially lethal infections. Correspondingly, pathogens have evolved with various strategies to modulate and circumvent the host's innate and adaptive immune response. Schistosoma species are helminth parasites with genes that have been selected to modulate the host to tolerate chronic worm infections, often for decades, without overt morbidity. The modulation of immunity by schistosomes has been shown to prevent a range of immune-mediated diseases, including allergies and autoimmunity. Individual immune-modulating schistosome molecules have, therefore, therapeutic potential as selective manipulators of the immune system to prevent unrelated diseases. Here we show that S. mansoni eggs secrete a protein into host tissues that binds certain chemokines and inhibits their interaction with host chemokine receptors and their biological activity. The purified recombinant S. mansoni chemokine binding protein (smCKBP) suppressed inflammation in several disease models. smCKBP is unrelated to host proteins and is the first described chemokine binding protein encoded by a pathogenic human parasite and may have potential as an antiinflammatory agent.

  11. A silent chemokine receptor regulates steady-state leukocyte homing in vivo

    PubMed Central

    Heinzel, Kornelia; Benz, Claudia; Bleul, Conrad C.

    2007-01-01

    The location of leukocytes in different microenvironments is intimately connected to their function and, in the case of leukocyte precursors, to the executed differentiation and maturation program. Leukocyte migration within lymphoid organs has been shown to be mediated by constitutively expressed chemokines, but how the bioavailability of these homeostatic chemokines is regulated remains unknown. Here, we report in vivo evidence for the role of a nonsignaling chemokine receptor in the migration of leukocytes under physiological, i.e., noninflammatory, conditions. We have studied the in vivo role of the silent chemokine receptor CCX-CKR1 by both loss- and gain-of-function approaches. CCX-CKR1 binds the constitutively expressed chemokines CC chemokine ligand (CCL)19, CCL21, and CCL25. We find that CCX-CKR1 is involved in the steady-state homing of CD11c+MHCIIhigh dendritic cells to skin-draining lymph nodes, and it affects the homing of embryonic thymic precursors to the thymic anlage. These observations indicate that the silent chemokine receptor CCX-CKR1, which is exclusively expressed by stroma cells, but not hematopoietic cells themselves, regulates homeostatic leukocyte migration by controlling the availability of chemokines in the extracellular space. This finding adds another level of complexity to our understanding of leukocyte homeostatic migration. PMID:17485674

  12. Hydrogen peroxide induces murine macrophage chemokine gene transcription via extracellular signal-regulated kinase- and cyclic adenosine 5'-monophosphate (cAMP)-dependent pathways: involvement of NF-kappa B, activator protein 1, and cAMP response element binding protein.

    PubMed

    Jaramillo, Maritza; Olivier, Martin

    2002-12-15

    Hydrogen peroxide (H(2)O(2)) has been shown to act as a second messenger that activates chemokine expression. In the present study, we investigated the mechanisms underlying this cellular regulation in the murine macrophage cell line B10R. We report that H(2)O(2) increases mRNA expression of various chemokines, macrophage-inflammatory protein (MIP)-1alpha/CC chemokine ligand (CCL)3, MIP-1beta/CCL4, MIP-2/CXC chemokine ligand 2, and monocyte chemoattractant protein-1/CCL2, by activating the extracellular signal-regulated kinase (ERK) pathway and the nuclear translocation of the transcription factors NF-kappaB, AP-1, and CREB. Blockage of the ERK pathway with specific inhibitors against mitogen-activated protein kinase kinase 1/2 and ERK1/ERK2 completely abolished both the H(2)O(2)-mediated chemokine up-regulation and the activation of all NF studied. Similarly, selective inhibition of cAMP and NF-kappaB strongly down-regulated the induction of all chemokine transcripts as well as CREB and NF-kappaB activation, respectively. Of interest, we detected a significant decrease of NF-kappaB, AP-1, and CREB DNA binding activities by reciprocal competition for these binding sites when either specific cold oligonucleotides (NF-kappaB, AP-1, and CREB) or Abs against various transcription factor subunits (p50, p65, c-Fos, Jun B, c-Jun, and CREB-1) were added. These findings indicate that cooperation between ERK- and cAMP-dependent pathways seems to be required to achieve the formation of an essential transcriptional factor complex for maximal H(2)O(2)-dependent chemokine modulation. Finally, experiments performed with actinomycin D suggest that H(2)O(2)-mediated MIP-1beta mRNA up-regulation results from transcriptional control, whereas that of MIP-1alpha, MIP-2, and monocyte chemoattractant protein-1 is due to both gene transcription activation and mRNA posttranscriptional stabilization.

  13. Opioid-induced chemokine expression requires NF-κB activity: the role of PKCζ.

    PubMed

    Happel, Christine; Kutzler, Michele; Rogers, Thomas J

    2011-02-01

    Opioid receptor agonists induce broad immunomodulatory activity, which substantially alters host defense and the inflammatory response. Previous studies have shown that the MOR selective agonist DAMGO has the capacity to increase the expression of the proinflammatory chemokines CCL2, CCL5, and CXCL10 in human PBMCs. NF-κB is a transcription factor that plays a pivotal role in innate and adaptive immune responses. We report that NF-κB is a vital player in the DAMGO-induced, MOR-mediated regulation of chemokine expression. Results show that NF-κB inhibitors prevent the induction of CCL2 expression in response to DAMGO administration and that the NF-κB subunit, p65, is phosphorylated at serine residues 311 and 536 in response to MOR activation. Furthermore, we demonstrate that PKCζ is phosphorylated following DAMGO-induced MOR activation, and this kinase is essential for NF-κB activation as well as CCL2 expression and transcriptional activity. Finally, ChIP analysis shows that DAMGO administration induces binding of p65 to the enhancer region of the CCL2 promoter. These data are consistent with the notion that MOR activation promotes a proinflammatory response, which involves NF-κB activation. Our results also suggest a significant and novel role for PKCζ as an essential participant in the MOR-mediated regulation of proinflammatory chemokine expression.

  14. Reduced locomotor activity and exploratory behavior in CC chemokine receptor 4 deficient mice.

    PubMed

    Ambrée, Oliver; Klassen, Irene; Förster, Irmgard; Arolt, Volker; Scheu, Stefanie; Alferink, Judith

    2016-11-01

    Chemokines and their receptors are key regulators of immune cell trafficking and activation. Recent findings suggest that they may also play pathophysiological roles in psychiatric diseases like depression and anxiety disorders. The CC chemokine receptor 4 (CCR4) and its two ligands, CCL17 and CCL22, are functionally involved in neuroinflammation as well as anti-infectious and autoimmune responses. However, their influence on behavior remains unknown. Here we characterized the functional role of the CCR4-CCL17 chemokine-receptor axis in the modulation of anxiety-related behavior, locomotor activity, and object exploration and recognition. Additionally, we investigated social exploration of CCR4 and CCL17 knockout mice and wild type (WT) controls. CCR4 knockout (CCR4(-/-)) mice exhibited fewer anxiety-related behaviors in the elevated plus-maze, diminished locomotor activity, exploratory behavior, and social exploration, while their recognition memory was not affected. In contrast, CCL17 deficient mice did not show an altered behavior compared to WT mice regarding locomotor activity, anxiety-related behavior, social exploration, and object recognition memory. In the dark-light and object recognition tests, CCL17(-/-) mice even covered longer distances than WT mice. These data demonstrate a mechanistic or developmental role of CCR4 in the regulation of locomotor and exploratory behaviors, whereas the ligand CCL17 appears not to be involved in the behaviors measured here. Thus, either CCL17 and the alternative ligand CCL22 may be redundant, or CCL22 is the main activator of CCR4 in these processes. Taken together, these findings contribute to the growing evidence regarding the involvement of chemokines and their receptors in the regulation of behavior.

  15. RGS1 regulates myeloid cell accumulation in atherosclerosis and aortic aneurysm rupture through altered chemokine signalling

    PubMed Central

    Patel, Jyoti; McNeill, Eileen; Douglas, Gillian; Hale, Ashley B.; de Bono, Joseph; Lee, Regent; Iqbal, Asif J.; Regan-Komito, Daniel; Stylianou, Elena; Greaves, David R.; Channon, Keith M.

    2015-01-01

    Chemokine signalling drives monocyte recruitment in atherosclerosis and aortic aneurysms. The mechanisms that lead to retention and accumulation of macrophages in the vascular wall remain unclear. Regulator of G-Protein Signalling-1 (RGS1) deactivates G-protein signalling, reducing the response to sustained chemokine stimulation. Here we show that Rgs1 is upregulated in atherosclerotic plaque and aortic aneurysms. Rgs1 reduces macrophage chemotaxis and desensitizes chemokine receptor signalling. In early atherosclerotic lesions, Rgs1 regulates macrophage accumulation and is required for the formation and rupture of Angiotensin II-induced aortic aneurysms, through effects on leukocyte retention. Collectively, these data reveal a role for Rgs1 in leukocyte trafficking and vascular inflammation and identify Rgs1, and inhibition of chemokine receptor signalling as potential therapeutic targets in vascular disease. PMID:25782711

  16. Up-regulated extracellular matrix components and inflammatory chemokines may impair the regeneration of cholestatic liver

    PubMed Central

    Zhang, Shuai; Li, Tao-Sheng; Soyama, Akihiko; Tanaka, Takayuki; Yan, Chen; Sakai, Yusuke; Hidaka, Masaaki; Kinoshita, Ayaka; Natsuda, Koji; Fujii, Mio; Kugiyama, Tota; Baimakhanov, Zhassulan; Kuroki, Tamotsu; Gu, Weili; Eguchi, Susumu

    2016-01-01

    Although the healthy liver is known to have high regenerative potential, poor liver regeneration under pathological conditions remains a substantial problem. We investigated the key molecules that impair the regeneration of cholestatic liver. C57BL/6 mice were randomly subjected to partial hepatectomy and bile duct ligation (PH+BDL group, n = 16), partial hepatectomy only (PH group, n = 16), or sham operation (Sham group, n = 16). The liver sizes and histological findings were similar in the PH and sham groups 14 days after operation. However, compared with those in the sham group, the livers in mice in the PH+BDL group had a smaller size, a lower cell proliferative activity, and more fibrotic tissue 14 days after the operation, suggesting the insufficient regeneration of the cholestatic liver. Pathway-focused array analysis showed that many genes were up- or down-regulated over 1.5-fold in both PH+BDL and PH groups at 1, 3, 7, and 14 days after treatment. Interestingly, more genes that were functionally related to the extracellular matrix and inflammatory chemokines were found in the PH+BDL group than in the PH group at 7 and 14 days after treatment. Our data suggest that up-regulated extracellular matrix components and inflammatory chemokines may impair the regeneration of cholestatic liver. PMID:27226149

  17. Up-regulated extracellular matrix components and inflammatory chemokines may impair the regeneration of cholestatic liver.

    PubMed

    Zhang, Shuai; Li, Tao-Sheng; Soyama, Akihiko; Tanaka, Takayuki; Yan, Chen; Sakai, Yusuke; Hidaka, Masaaki; Kinoshita, Ayaka; Natsuda, Koji; Fujii, Mio; Kugiyama, Tota; Baimakhanov, Zhassulan; Kuroki, Tamotsu; Gu, Weili; Eguchi, Susumu

    2016-01-01

    Although the healthy liver is known to have high regenerative potential, poor liver regeneration under pathological conditions remains a substantial problem. We investigated the key molecules that impair the regeneration of cholestatic liver. C57BL/6 mice were randomly subjected to partial hepatectomy and bile duct ligation (PH+BDL group, n = 16), partial hepatectomy only (PH group, n = 16), or sham operation (Sham group, n = 16). The liver sizes and histological findings were similar in the PH and sham groups 14 days after operation. However, compared with those in the sham group, the livers in mice in the PH+BDL group had a smaller size, a lower cell proliferative activity, and more fibrotic tissue 14 days after the operation, suggesting the insufficient regeneration of the cholestatic liver. Pathway-focused array analysis showed that many genes were up- or down-regulated over 1.5-fold in both PH+BDL and PH groups at 1, 3, 7, and 14 days after treatment. Interestingly, more genes that were functionally related to the extracellular matrix and inflammatory chemokines were found in the PH+BDL group than in the PH group at 7 and 14 days after treatment. Our data suggest that up-regulated extracellular matrix components and inflammatory chemokines may impair the regeneration of cholestatic liver. PMID:27226149

  18. Up-regulated extracellular matrix components and inflammatory chemokines may impair the regeneration of cholestatic liver.

    PubMed

    Zhang, Shuai; Li, Tao-Sheng; Soyama, Akihiko; Tanaka, Takayuki; Yan, Chen; Sakai, Yusuke; Hidaka, Masaaki; Kinoshita, Ayaka; Natsuda, Koji; Fujii, Mio; Kugiyama, Tota; Baimakhanov, Zhassulan; Kuroki, Tamotsu; Gu, Weili; Eguchi, Susumu

    2016-01-01

    Although the healthy liver is known to have high regenerative potential, poor liver regeneration under pathological conditions remains a substantial problem. We investigated the key molecules that impair the regeneration of cholestatic liver. C57BL/6 mice were randomly subjected to partial hepatectomy and bile duct ligation (PH+BDL group, n = 16), partial hepatectomy only (PH group, n = 16), or sham operation (Sham group, n = 16). The liver sizes and histological findings were similar in the PH and sham groups 14 days after operation. However, compared with those in the sham group, the livers in mice in the PH+BDL group had a smaller size, a lower cell proliferative activity, and more fibrotic tissue 14 days after the operation, suggesting the insufficient regeneration of the cholestatic liver. Pathway-focused array analysis showed that many genes were up- or down-regulated over 1.5-fold in both PH+BDL and PH groups at 1, 3, 7, and 14 days after treatment. Interestingly, more genes that were functionally related to the extracellular matrix and inflammatory chemokines were found in the PH+BDL group than in the PH group at 7 and 14 days after treatment. Our data suggest that up-regulated extracellular matrix components and inflammatory chemokines may impair the regeneration of cholestatic liver.

  19. Polysialylation controls dendritic cell trafficking by regulating chemokine recognition.

    PubMed

    Kiermaier, Eva; Moussion, Christine; Veldkamp, Christopher T; Gerardy-Schahn, Rita; de Vries, Ingrid; Williams, Larry G; Chaffee, Gary R; Phillips, Andrew J; Freiberger, Friedrich; Imre, Richard; Taleski, Deni; Payne, Richard J; Braun, Asolina; Förster, Reinhold; Mechtler, Karl; Mühlenhoff, Martina; Volkman, Brian F; Sixt, Michael

    2016-01-01

    The addition of polysialic acid to N- and/or O-linked glycans, referred to as polysialylation, is a rare posttranslational modification that is mainly known to control the developmental plasticity of the nervous system. Here we show that CCR7, the central chemokine receptor controlling immune cell trafficking to secondary lymphatic organs, carries polysialic acid. This modification is essential for the recognition of the CCR7 ligand CCL21. As a consequence, dendritic cell trafficking is abrogated in polysialyltransferase-deficient mice, manifesting as disturbed lymph node homeostasis and unresponsiveness to inflammatory stimuli. Structure-function analysis of chemokine-receptor interactions reveals that CCL21 adopts an autoinhibited conformation, which is released upon interaction with polysialic acid. Thus, we describe a glycosylation-mediated immune cell trafficking disorder and its mechanistic basis. PMID:26657283

  20. Chemokines derived from soluble fusion proteins expressed in Escherichia coli are biologically active

    SciTech Connect

    Magistrelli, Giovanni; Gueneau, Franck; Muslmani, Machadiya; Ravn, Ulla; Kosco-Vilbois, Marie; Fischer, Nicolas . E-mail: nfischer@novimmune.com

    2005-08-26

    Chemokines are a class of low molecular weight proteins that are involved in leukocytes trafficking. Due to their involvement in recruiting immune cells to sites of inflammation, chemokines, and chemokine receptors have become an attractive class of therapeutic targets. However, when expressed in Escherichia coli chemokines are poorly soluble and accumulate in inclusion bodies. Several purification methods have been described but involve time-consuming refolding, buffer exchange, and purification steps that complicate expression of these proteins. Here, we describe a simple and reliable method to express chemokines as fusions to the protein NusA. The fusion proteins were largely found in the soluble fraction and could be readily purified in a single step. Proteolytic cleavage was used to obtain soluble recombinant chemokines that were found to be very active in a novel in vitro chemotaxis assays. This method could be applied to several {alpha} and {beta} human chemokines, suggesting that it is generally applicable to this class of proteins.

  1. CXC Chemokine Receptor 3 Alternative Splice Variants Selectively Activate Different Signaling Pathways.

    PubMed

    Berchiche, Yamina A; Sakmar, Thomas P

    2016-10-01

    The G protein-coupled receptor (GPCR) C-X-C chemokine receptor 3 (CXCR3) is a potential drug target that mediates signaling involved in cancer metastasis and inflammatory diseases. The CXCR3 primary transcript has three potential alternative splice variants and cell-type specific expression results in receptor variants that are believed to have different functional characteristics. However, the molecular pharmacology of ligand binding to CXCR3 alternative splice variants and their downstream signaling pathways remain poorly explored. To better understand the role of the functional consequences of alternative splicing of CXCR3, we measured signaling in response to four different chemokine ligands (CXCL4, CXCL9, CXCL10, and CXCL11) with agonist activity at CXCR3. Both CXCL10 and CXCL11 activated splice variant CXCR3A. Whereas CXCL10 displayed full agonistic activity for Gαi activation and extracellular signal regulated kinase (ERK) 1/2 phosphorylation and partial agonist activity for β-arrestin recruitment, CXCL9 triggered only modest ERK1/2 phosphorylation. CXCL11 induced CXCR3B-mediated β-arrestin recruitment and little ERK phosphorylation. CXCR3Alt signaling was limited to modest ligand-induced receptor internalization and ERK1/2 phosphorylation in response to chemokines CXCL11, CXCL10, and CXCL9. These results show that CXCR3 splice variants activate different signaling pathways and that CXCR3 variant function is not redundant, suggesting a mechanism for tissue specific biased agonism. Our data show an additional layer of complexity for chemokine receptor signaling that might be exploited to target specific CXCR3 splice variants. PMID:27512119

  2. Regulation of human natural killer cell migration and proliferation by the exodus subfamily of CC chemokines.

    PubMed

    Robertson, M J; Williams, B T; Christopherson, K; Brahmi, Z; Hromas, R

    2000-01-10

    Natural killer (NK) cells play an important role in innate and adaptive immune responses to obligate intracellular pathogens. Nevertheless, the regulation of NK cell trafficking and migration to inflammatory sites is poorly understood. Exodus-1/MIP-3alpha/LARC, Exodus-2/6Ckine/SLC, and Exodus-3/MIP-3beta/ELC/CKbeta-11 are CC chemokines that share a unique aspartate-cysteine-cysteine-leucine motif near their amino terminus and preferentially stimulate the migration of T lymphocytes. The effects of Exodus chemokines on human NK cells were examined. Exodus-1, -2, and -3 did not induce detectable chemotaxis of resting peripheral blood NK cells. In contrast, Exodus-2 and -3 stimulated migration of polyclonal activated peripheral blood NK cells in a dose-dependent fashion. Exodus-2 and -3 also induced dose-dependent chemotaxis of NKL, an IL-2-dependent human NK cell line. Results of modified checkerboard assays indicate that migration of NKL cells in response to Exodus-2 and -3 represents true chemotaxis and not simply chemokinesis. Exodus-1, -2, and -3 did not induce NK cell proliferation in the absence of other stimuli. Nevertheless, Exodus-2 and -3 significantly augmented IL-2-induced proliferation of normal human CD56(dim) NK cells. In contrast, Exodus-1, -2, and -3 did not affect the cytolytic activity of resting or activated peripheral blood NK cells. Expression of message for CCR7, a shared receptor for Exodus-2 and -3, was detected in activated polyclonal NK cells and NKL cells but not resting NK cells. Taken together, these results indicate that Exodus-2 and -3 can participate in the recruitment and proliferation of activated NK cells. Exodus-2 and -3 may regulate interactions between T cells and NK cells that are crucial for the generation of optimal immune responses.

  3. Chemokines accentuating protumoral activities in oral cancer microenvironment possess an imperious stratagem for therapeutic resolutions.

    PubMed

    Panda, Swagatika; Padhiary, Subrat Kumar; Routray, Samapika

    2016-09-01

    Chemokines, the chemotactic cytokines have established their role in tumorigenesis and tumor progression. Studies, which explored their role in oral cancer for protumoral activity, point towards targeting chemokines for oral squamous cell carcinoma therapy. The need of the hour is to emphasize/divulge in the activities of chemokine ligands and their receptors in the tumor microenvironment for augmentation of such stratagems. This progressing sentience of chemokines and their receptors has inspired this review which is an endeavour to comprehend their role as an aid in accentuating hallmarks of cancer and targeted therapy. PMID:27531867

  4. The role of adenosine receptors in regulating production of tumour necrosis factor-α and chemokines by human lung macrophages

    PubMed Central

    Buenestado, A; Delyle, S Grassin; Arnould, I; Besnard, F; Naline, E; Blouquit-Laye, S; Chapelier, A; Bellamy, JF; Devillier, P

    2010-01-01

    Background and purpose: Adenosine is a major endogenous regulator of macrophage function, and activates four specific adenosine receptors (A1, A2A, A2B and A3). Here, we have assessed in human lung macrophages the modulation of the expression of adenosine receptor mRNA by lipopolysaccharide (LPS), and the relative contributions of the different adenosine receptors to LPS-induced production of tumour necrosis factor (TNF)-α and chemokines. Experimental approach: Lung macrophages isolated from resected lungs were stimulated with LPS and treated with adenosine receptor agonists or/and antagonists. Adenosine receptor expression was assessed with qRT-PCR. Cytokines were measured in lung macrophage supernatants with elisa. Key results: LPS increased (about 400-fold) mRNA for A2A adenosine receptors, decreased mRNA for A1 and A2B, but had no effect on A3 adenosine receptor mRNA. The adenosine receptor agonist NECA inhibited TNF-α production concentration dependently, whereas the A1 receptor agonist, CCPA, and the A3 receptor agonist, AB-MECA, inhibited TNF-α production only at concentrations affecting A2A receptors. NECA also inhibited the production of CCL chemokines (CCL2, CCL3, CCL4, CCL5) and CXCL chemokines (CXCL9 and CXCL10), but not that of CXCL1, CXCL8 and CXCL5. Reversal of NECA-induced inhibition of TNF-α and chemokine production by the selective A2A adenosine receptor antagonist ZM 241385, but not the A2B receptor antagonist, MRS 1754, or the A3 receptor antagonist, MRS 1220, indicated involvement of A2A receptors. Conclusions and implications: LPS up-regulated A2A adenosine receptor gene transcription, and this receptor subtype mediated inhibition of the LPS-induced production of TNF-α and of a subset of chemokines in human lung macrophages. PMID:20136829

  5. Activating Transcription Factor 3-mediated Chemo-intervention with Cancer Chemokines in a Noncanonical Pathway under Endoplasmic Reticulum Stress*

    PubMed Central

    Park, Seong-Hwan; Kim, Juil; Do, Kee Hun; Park, Jiyeon; Oh, Chang Gyu; Choi, Hye Jin; Song, Bo Gyoung; Lee, Seung Joon; Kim, Yong Sik; Moon, Yuseok

    2014-01-01

    The cell-protective features of the endoplasmic reticulum (ER) stress response are chronically activated in vigorously growing malignant tumor cells, which provide cellular growth advantages over the adverse microenvironment including chemotherapy. As an intervention with ER stress responses in the intestinal cancer cells, preventive exposure to flavone apigenin potentiated superinduction of a regulatory transcription factor, activating transcription factor 3 (ATF3), which is also known to be an integral player coordinating ER stress response-related gene expression. ATF3 superinduction was due to increased turnover of ATF3 transcript via stabilization with HuR protein in the cancer cells under ER stress. Moreover, enhanced ATF3 caused inhibitory action against ER stress-induced cancer chemokines that are potent mediators determining the survival and metastatic potential of epithelial cancer cells. Although enhanced ATF3 was a negative regulator of the well known proinflammatory transcription factor NF-κB, blocking of NF-κB signaling did not affect ER stress-induced chemokine expression. Instead, immediately expressed transcription factor early growth response protein 1 (EGR-1) was positively involved in cancer chemokine induction by ER stressors. ER stress-induced EGR-1 and subsequent chemokine production were repressed by ATF3. Mechanistically, ATF3 directly interacted with and recruited HDAC1 protein, which led to epigenetic suppression of EGR-1 expression and subsequent chemokine production. Conclusively, superinduced ATF3 attenuated ER stress-induced cancer chemokine expression by epigenetically interfering with induction of EGR-1, a transcriptional modulator crucial to cancer chemokine production. Thus, these results suggest a potent therapeutic intervention of ER stress response-related cancer-favoring events by ATF3. PMID:25122760

  6. Activating transcription factor 3-mediated chemo-intervention with cancer chemokines in a noncanonical pathway under endoplasmic reticulum stress.

    PubMed

    Park, Seong-Hwan; Kim, Juil; Do, Kee Hun; Park, Jiyeon; Oh, Chang Gyu; Choi, Hye Jin; Song, Bo Gyoung; Lee, Seung Joon; Kim, Yong Sik; Moon, Yuseok

    2014-09-26

    The cell-protective features of the endoplasmic reticulum (ER) stress response are chronically activated in vigorously growing malignant tumor cells, which provide cellular growth advantages over the adverse microenvironment including chemotherapy. As an intervention with ER stress responses in the intestinal cancer cells, preventive exposure to flavone apigenin potentiated superinduction of a regulatory transcription factor, activating transcription factor 3 (ATF3), which is also known to be an integral player coordinating ER stress response-related gene expression. ATF3 superinduction was due to increased turnover of ATF3 transcript via stabilization with HuR protein in the cancer cells under ER stress. Moreover, enhanced ATF3 caused inhibitory action against ER stress-induced cancer chemokines that are potent mediators determining the survival and metastatic potential of epithelial cancer cells. Although enhanced ATF3 was a negative regulator of the well known proinflammatory transcription factor NF-κB, blocking of NF-κB signaling did not affect ER stress-induced chemokine expression. Instead, immediately expressed transcription factor early growth response protein 1 (EGR-1) was positively involved in cancer chemokine induction by ER stressors. ER stress-induced EGR-1 and subsequent chemokine production were repressed by ATF3. Mechanistically, ATF3 directly interacted with and recruited HDAC1 protein, which led to epigenetic suppression of EGR-1 expression and subsequent chemokine production. Conclusively, superinduced ATF3 attenuated ER stress-induced cancer chemokine expression by epigenetically interfering with induction of EGR-1, a transcriptional modulator crucial to cancer chemokine production. Thus, these results suggest a potent therapeutic intervention of ER stress response-related cancer-favoring events by ATF3.

  7. Structural basis for chemokine recognition and activation of a viral G protein-coupled receptor

    SciTech Connect

    Burg, John S.; Ingram, Jessica R.; Venkatakrishnan, A.J.; Jude, Kevin M.; Dukkipati, Abhiram; Feinberg, Evan N.; Angelini, Alessandro; Waghray, Deepa; Dror, Ron O.; Ploegh, Hidde L.; Garcia, K. Christopher

    2015-03-05

    Chemokines are small proteins that function as immune modulators through activation of chemokine G protein-coupled receptors (GPCRs). Several viruses also encode chemokines and chemokine receptors to subvert the host immune response. How protein ligands activate GPCRs remains unknown. We report the crystal structure at 2.9 angstrom resolution of the human cytomegalovirus GPCR US28 in complex with the chemokine domain of human CX3CL1 (fractalkine). The globular body of CX3CL1 is perched on top of the US28 extracellular vestibule, whereas its amino terminus projects into the central core of US28. The transmembrane helices of US28 adopt an active-state-like conformation. Atomic-level simulations suggest that the agonist-independent activity of US28 may be due to an amino acid network evolved in the viral GPCR to destabilize the receptor’s inactive state.

  8. Structural basis for chemokine recognition and activation of a viral G protein–coupled receptor

    PubMed Central

    Burg, John S.; Ingram, Jessica R.; Venkatakrishnan, A. J.; Jude, Kevin M.; Dukkipati, Abhiram; Feinberg, Evan N.; Angelini, Alessandro; Waghray, Deepa; Dror, Ron O.; Ploegh, Hidde L.; Garcia, K. Christopher

    2015-01-01

    Chemokines are small proteins that function as immune modulators through activation of chemokine G protein–coupled receptors (GPCRs). Several viruses also encode chemokines and chemokine receptors to subvert the host immune response. How protein ligands activate GPCRs remains unknown. We report the crystal structure at 2.9 angstrom resolution of the human cytomegalovirus GPCR US28 in complex with the chemokine domain of human CX3CL1 (fractalkine). The globular body of CX3CL1 is perched on top of the US28 extracellular vestibule, whereas its amino terminus projects into the central core of US28. The transmembrane helices of US28 adopt an active-state–like conformation. Atomic-level simulations suggest that the agonist-independent activity of US28 may be due to an amino acid network evolved in the viral GPCR to destabilize the receptor’s inactive state. PMID:25745166

  9. The chemokine CCL2 activates p38 mitogen-activated protein kinase pathway in cultured rat hippocampal cells

    PubMed Central

    Cho, Jungsook; Gruol, Donna L.

    2008-01-01

    Emerging evidence indicates that chemokines can regulate both the physiology and biochemistry of CNS neurons and glia. In the current study, Western blot analysis showed that in rat hippocampal neuronal/glial cultures the signal transduction pathway activated by CCL2, a chemokine expressed in the normal brain and at elevated levels during neuroinflammation, involves a G-protein coupled receptor, p38 MAPK as well as its immediate upstream kinase MKK3/6, and the downstream transcription factor CREB. ERK 1/2 and the transcription factors STAT1 and STAT3 do not play a prominent role. CCL2 also altered Ca2+ influx and synaptic network activity in the hippocampal neurons. These results suggest an important role for p38 MAPK and CREB in hippocampal actions of CCL2. PMID:18584881

  10. Chemokine Receptors, CXCR1 and CXCR2, Differentially Regulate Exosome Release in Hepatocytes.

    PubMed

    Nojima, Hiroyuki; Konishi, Takanori; Freeman, Christopher M; Schuster, Rebecca M; Japtok, Lukasz; Kleuser, Burkhard; Edwards, Michael J; Gulbins, Erich; Lentsch, Alex B

    2016-01-01

    Exosomes are small membrane vesicles released by different cell types, including hepatocytes, that play important roles in intercellular communication. We have previously demonstrated that hepatocyte-derived exosomes contain the synthetic machinery to form sphingosine-1-phosphate (S1P) in target hepatocytes resulting in proliferation and liver regeneration after ischemia/reperfusion (I/R) injury. We also demonstrated that the chemokine receptors, CXCR1 and CXCR2, regulate liver recovery and regeneration after I/R injury. In the current study, we sought to determine if the regulatory effects of CXCR1 and CXCR2 on liver recovery and regeneration might occur via altered release of hepatocyte exosomes. We found that hepatocyte release of exosomes was dependent upon CXCR1 and CXCR2. CXCR1-deficient hepatocytes produced fewer exosomes, whereas CXCR2-deficient hepatocytes produced more exosomes compared to their wild-type controls. In CXCR2-deficient hepatocytes, there was increased activity of neutral sphingomyelinase (Nsm) and intracellular ceramide. CXCR1-deficient hepatocytes had no alterations in Nsm activity or ceramide production. Interestingly, exosomes from CXCR1-deficient hepatocytes had no effect on hepatocyte proliferation, due to a lack of neutral ceramidase and sphingosine kinase. The data demonstrate that CXCR1 and CXCR2 regulate hepatocyte exosome release. The mechanism utilized by CXCR1 remains elusive, but CXCR2 appears to modulate Nsm activity and resultant production of ceramide to control exosome release. CXCR1 is required for packaging of enzymes into exosomes that mediate their hepatocyte proliferative effect. PMID:27551720

  11. Chemokine Receptors, CXCR1 and CXCR2, Differentially Regulate Exosome Release in Hepatocytes

    PubMed Central

    Nojima, Hiroyuki; Konishi, Takanori; Freeman, Christopher M.; Schuster, Rebecca M.; Japtok, Lukasz; Kleuser, Burkhard; Edwards, Michael J.; Gulbins, Erich; Lentsch, Alex B.

    2016-01-01

    Exosomes are small membrane vesicles released by different cell types, including hepatocytes, that play important roles in intercellular communication. We have previously demonstrated that hepatocyte-derived exosomes contain the synthetic machinery to form sphingosine-1-phosphate (S1P) in target hepatocytes resulting in proliferation and liver regeneration after ischemia/reperfusion (I/R) injury. We also demonstrated that the chemokine receptors, CXCR1 and CXCR2, regulate liver recovery and regeneration after I/R injury. In the current study, we sought to determine if the regulatory effects of CXCR1 and CXCR2 on liver recovery and regeneration might occur via altered release of hepatocyte exosomes. We found that hepatocyte release of exosomes was dependent upon CXCR1 and CXCR2. CXCR1-deficient hepatocytes produced fewer exosomes, whereas CXCR2-deficient hepatocytes produced more exosomes compared to their wild-type controls. In CXCR2-deficient hepatocytes, there was increased activity of neutral sphingomyelinase (Nsm) and intracellular ceramide. CXCR1-deficient hepatocytes had no alterations in Nsm activity or ceramide production. Interestingly, exosomes from CXCR1-deficient hepatocytes had no effect on hepatocyte proliferation, due to a lack of neutral ceramidase and sphingosine kinase. The data demonstrate that CXCR1 and CXCR2 regulate hepatocyte exosome release. The mechanism utilized by CXCR1 remains elusive, but CXCR2 appears to modulate Nsm activity and resultant production of ceramide to control exosome release. CXCR1 is required for packaging of enzymes into exosomes that mediate their hepatocyte proliferative effect. PMID:27551720

  12. Chemokines in tumor development and progression

    SciTech Connect

    Mukaida, Naofumi; Baba, Tomohisa

    2012-01-15

    Chemokines were originally identified as mediators of the inflammatory process and regulators of leukocyte trafficking. Subsequent studies revealed their essential roles in leukocyte physiology and pathology. Moreover, chemokines have profound effects on other types of cells associated with the inflammatory response, such as endothelial cells and fibroblasts. Thus, chemokines are crucial for cancer-related inflammation, which can promote tumor development and progression. Increasing evidence points to the vital effects of several chemokines on the proliferative and invasive properties of tumor cells. The wide range of activities of chemokines in tumorigenesis highlights their roles in tumor development and progression.

  13. Omega-3 fatty acids inhibit the up-regulation of endothelial chemokines in maintenance hemodialysis patients

    PubMed Central

    Hung, Adriana M.; Booker, Cindy; Ellis, Charles D.; Siew, Edward D.; Graves, Amy J.; Shintani, Ayumi; Abumrad, Naji N.; Himmelfarb, Jonathan; Ikizler, Talat Alp

    2015-01-01

    Background Chronic systemic inflammation is common in patients with chronic kidney disease on dialysis (CKD5D) and has been considered a key mediator of the increased cardiovascular risk in this patient population. In this study, we tested the hypothesis that supplementation of omega-3 polyunsaturated fatty acids (ω-3 PUFAs) will attenuate the systemic inflammatory process in CKD5D patients. Methods The design was a randomized, double-blinded, placebo controlled pilot trial (NCT00655525). Thirty-eight patients were randomly assigned in a 1 : 1 fashion to receive 2.9 g of eicosapentaenoic acid (C20:5, n-3) plus docosahexaenoic acid (C22:6, n-3) versus placebo for 12 weeks. The primary outcome was change in pro-inflammatory chemokines measured by lipopolysaccharide (LPS)-stimulated peripheral blood mononuclear cells (PBMCs). Secondary outcomes were changes in systemic inflammatory markers. Analysis of covariance was used to compare percent change from baseline to 12 weeks. Results Thirty-one patients completed 12 weeks and three patients completed 6 weeks of the study. Median age was 52 (interquartile range 45, 60) years, 74% were African-American and 79% were male. Supplementation of ω-3 PUFAs effectively decreased the LPS-induced PBMC expression of RANTES (Regulated upon Activation, Normal T cell Expressed and Secreted) and MCP-1 (Monocyte Chemotactic Protein-1; unadjusted P = 0.04 and 0.06; adjusted for demographics P = 0.02 and 0.05, respectively). There was no significant effect of the intervention on serum inflammatory markers (C-reactive protein, interleukin-6 and procalcitonin). Conclusions The results of this pilot study suggest that supplementation of ω-3 PUFAs is beneficial in decreasing the levels of endothelial chemokines, RANTES and MCP-1. Studies of larger sample size and longer duration are required to further evaluate effects of ω-3 PUFAs on systemic markers of inflammation, other metabolic parameters and clinical outcomes, particularly

  14. Cytokines and Chemokines as Regulators of Skeletal Muscle Inflammation: Presenting the Case of Duchenne Muscular Dystrophy

    PubMed Central

    De Bleecker, Jan L.

    2013-01-01

    Duchenne muscular dystrophy is a severe inherited muscle disease that affects 1 in 3500 boys worldwide. Infiltration of skeletal muscle by inflammatory cells is an important facet of disease pathophysiology and is strongly associated with disease severity in the individual patient. In the chronic inflammation that characterizes Duchenne muscle, cytokines and chemokines are considered essential activators and recruiters of inflammatory cells. In addition, they provide potential beneficiary effects on muscle fiber damage control and tissue regeneration. In this review, current knowledge of cytokine and chemokine expression in Duchenne muscular dystrophy and its relevant animal disease models is listed, and implications for future therapeutic avenues are discussed. PMID:24302815

  15. Activation of prostaglandin E2-EP4 signaling reduces chemokine production in adipose tissue.

    PubMed

    Tang, Eva H C; Cai, Yin; Wong, Chi Kin; Rocha, Viviane Z; Sukhova, Galina K; Shimizu, Koichi; Xuan, Ge; Vanhoutte, Paul M; Libby, Peter; Xu, Aimin

    2015-02-01

    Inflammation of adipose tissue induces metabolic derangements associated with obesity. Thus, determining ways to control or inhibit inflammation in adipose tissue is of clinical interest. The present study tested the hypothesis that in mouse adipose tissue, endogenous prostaglandin E2 (PGE2) negatively regulates inflammation via activation of prostaglandin E receptor 4 (EP4). PGE2 (5-500 nM) attenuated lipopolysaccharide-induced mRNA and protein expression of chemokines, including interferon-γ-inducible protein 10 and macrophage-inflammatory protein-1α in mouse adipose tissue. A selective EP4 antagonist (L161,982) reversed, and two structurally different selective EP4 agonists [CAY10580 and CAY10598] mimicked these actions of PGE2. Adipose tissue derived from EP4-deficient mice did not display this response. These findings establish the involvement of EP4 receptors in this anti-inflammatory response. Experiments performed on adipose tissue from high-fat-fed mice demonstrated EP4-dependent attenuation of chemokine production during diet-induced obesity. The anti-inflammatory actions of EP4 became more important on a high-fat diet, in that EP4 activation suppressed a greater variety of chemokines. Furthermore, adipose tissue and systemic inflammation was enhanced in high-fat-fed EP4-deficient mice compared with wild-type littermates, and in high-fat-fed untreated C57BL/6 mice compared with mice treated with EP4 agonist. These findings provide in vivo evidence that PGE2-EP4 signaling limits inflammation. In conclusion, PGE2, via activation of EP4 receptors, functions as an endogenous anti-inflammatory mediator in mouse adipose tissue, and targeting EP4 may mitigate adipose tissue inflammation.

  16. A Requirement for Metamorphic Interconversion in the Antimicrobial Activity of Chemokine XCL1.

    PubMed

    Nevins, Amanda M; Subramanian, Akshay; Tapia, Jazma L; Delgado, David P; Tyler, Robert C; Jensen, Davin R; Ouellette, André J; Volkman, Brian F

    2016-07-12

    Chemokines make up a superfamily of ∼50 small secreted proteins (8-12 kDa) involved in a host of physiological processes and disease states, with several previously shown to have direct antimicrobial activity comparable to that of defensins in efficacy. XCL1 is a unique metamorphic protein that interconverts between the canonical chemokine fold and a novel all-β-sheet dimer. Phylogenetic analysis suggests that, within the chemokine family, XCL1 is most closely related to CCL20, which exhibits antibacterial activity. The in vitro antimicrobial activity of WT-XCL1 and structural variants was quantified using a radial diffusion assay (RDA) and in solution bactericidal assays against Gram-positive and Gram-negative species of bacteria. Comparisons of WT-XCL1 with variants that limit metamorphic interconversion showed a loss of antimicrobial activity when restricted to the conserved chemokine fold. These results suggest that metamorphic folding of XCL1 is required for potent antimicrobial activity.

  17. Monocyte chemotactic protein 3 is a most effective basophil- and eosinophil-activating chemokine

    PubMed Central

    1994-01-01

    CC chemokines constitute a novel class of cytokines that attract and activate monocytes and lymphocytes, as well as basophil and eosinophil leukocytes, with distinct target cell profiles, and are believed to be involved in the regulation of different types of inflammation. The action of the recently identified monocyte chemotactic protein 3 (MCP- 3) on human basophil and eosinophil function was studied and compared with that of other CC chemokines. In basophils, MCP-3, MCP-1, RANTES, and macrophage inflammatory protein (MIP)-1 alpha all induced cytosolic- free calcium concentration ([Ca2+]i) changes and, with different efficacies, chemotaxis (RANTES = MCP-3 >> MCP-1 > MIP-1 alpha), histamine release (MCP-1 = MCP-3 >> RANTES > MIP-1 alpha), and leukotriene C4 formation, after IL-3 pretreatment (MCP-1 = MCP-3 >> RANTES > MIP-1 alpha). Thus, MCP-3 was as effective as MCP-1 as an inducer of mediator release, and as effective as RANTES as a stimulus of basophil migration. In contrast to MCP-1, MCP-3 was also a stimulus for eosinophils, and induced [Ca2+]i changes and chemotaxis as effectively as RANTES, which is the most potent chemotactic cytokine for these cells. Desensitization of the transient changes in [Ca2+]i was used to assess receptor usage. In basophils, stimulation with MCP-3 prevented responsiveness to MCP-1 and RANTES, but not to MIP-1 alpha. No single CC chemokine (except for MCP-3 itself) affected the response to MCP-3, however, which was prevented only when the cells were prestimulated with both MCP-1 and RANTES. In eosinophils, by contrast, cross-desensitization between RANTES and MCP-3 was obtained. RANTES and to a lesser extent MCP-3 also desensitized eosinophils toward MIP-1 alpha. The desensitization data suggest the existence of three chemokine receptors: (a) a MCP-1 receptor expressed on basophils but not eosinophils that is activated by MCP-1 and MCP-3; (b) a RANTES receptor in basophils and eosinophils that is activated by RANTES and MCP-3; and

  18. Mechanisms regulating cell membrane localization of the chemokine receptor CXCR4 in human hepatocarcinoma cells.

    PubMed

    Cepeda, Edgar B; Dediulia, Tatjana; Fernando, Joan; Bertran, Esther; Egea, Gustavo; Navarro, Estanislao; Fabregat, Isabel

    2015-05-01

    Hepatocellular carcinoma (HCC) cells with a mesenchymal phenotype show an asymmetric subcellular distribution of the chemokine receptor CXCR4, which is required for cell migration and invasion. In this work we examine the mechanisms that regulate the intracellular trafficking of CXCR4 in HCC cells. Results indicate that HCC cells present CXCR4 at the cell surface, but most of this protein is in endomembranes colocalizing with markers of the Golgi apparatus and recycling endosomes. The presence of high protein levels of CXCR4 present at the cell surface correlates with a mesenchymal-like phenotype and a high autocrine activation of the Transforming Growth Factor-beta (TGF-β) pathway. CXCR4 traffics along the Golgi/exocyst/plasma membrane pathway and requires EXOC4 (Sec8) component of the exocyst complex. HCC cells use distinct mechanisms for the CXCR4 internalization such as dynamin-dependent endocytosis and macropinocytosis. Regardless of the endocytic mechanisms, colocalization of CXCR4 and Rab11 is observed, which could be involved not only in receptor recycling but also in its post-Golgi transport. In summary, this work highlights membrane trafficking pathways whose pharmacological targeting could subsequently result in the inactivation of one of the main guiding mechanisms used by metastatic cells to colonize secondary organs and tissues.

  19. Mechanisms regulating cell membrane localization of the chemokine receptor CXCR4 in human hepatocarcinoma cells.

    PubMed

    Cepeda, Edgar B; Dediulia, Tatjana; Fernando, Joan; Bertran, Esther; Egea, Gustavo; Navarro, Estanislao; Fabregat, Isabel

    2015-05-01

    Hepatocellular carcinoma (HCC) cells with a mesenchymal phenotype show an asymmetric subcellular distribution of the chemokine receptor CXCR4, which is required for cell migration and invasion. In this work we examine the mechanisms that regulate the intracellular trafficking of CXCR4 in HCC cells. Results indicate that HCC cells present CXCR4 at the cell surface, but most of this protein is in endomembranes colocalizing with markers of the Golgi apparatus and recycling endosomes. The presence of high protein levels of CXCR4 present at the cell surface correlates with a mesenchymal-like phenotype and a high autocrine activation of the Transforming Growth Factor-beta (TGF-β) pathway. CXCR4 traffics along the Golgi/exocyst/plasma membrane pathway and requires EXOC4 (Sec8) component of the exocyst complex. HCC cells use distinct mechanisms for the CXCR4 internalization such as dynamin-dependent endocytosis and macropinocytosis. Regardless of the endocytic mechanisms, colocalization of CXCR4 and Rab11 is observed, which could be involved not only in receptor recycling but also in its post-Golgi transport. In summary, this work highlights membrane trafficking pathways whose pharmacological targeting could subsequently result in the inactivation of one of the main guiding mechanisms used by metastatic cells to colonize secondary organs and tissues. PMID:25704914

  20. Signal pathways in up-regulation of chemokines by tyrosine kinase MER/NYK in prostate cancer cells.

    PubMed

    Wu, Yi-Mi; Robinson, Dan R; Kung, Hsing-Jien

    2004-10-15

    The AXL/UFO family of tyrosine kinases is characterized by a common N-CAM (neural adhesion molecule)-related extracellular domain and a common ligand, GAS6 (growth arrest-specific protein 6). Family members are prone to transcriptional regulation and carry out diverse functions including the regulation of cell adhesion, migration, phagocytosis, and survival. In this report, we describe a new role of MER/N-CAM-related kinase (NYK), a member of the AXL family of kinases, in the up-regulation of chemokines in prostate cancer cells. We show that NYK has elevated expression in a subset of tumor specimens and prostate cancer cell lines. Activation of NYK in the prostate cancer cell line DU145 does not cause a mitogenic effect; instead, it causes a differentiation phenotype. Microarray analysis revealed that NYK is a strong inducer of endocrine factors including interleukin (IL)-8 and several other angiogenic CXC chemokines as well as bone morphogenic factors. The dramatic increase of IL-8 expression is seen at both transcriptional and posttranscriptional levels. The downstream signals engaged by NYK were characterized, and those responsible for the up-regulation of IL-8 transcription were defined. In contrast to IL-1alpha, NYK-induced up-regulation of IL-8 in DU145 depends on the mitogen-activated protein kinase kinase/extracellular signal-regulated kinase/Jun/Fos pathway, but not phosphoinositide 3'-kinase/nuclear factor-kappaB. These data define a new function of the AXL family of kinases and suggest a potential role of NYK in prostate cancer progression. PMID:15492251

  1. Intermediate-conductance calcium-activated potassium channel KCa3.1 and chloride channel modulate chemokine ligand (CCL19/CCL21)-induced migration of dendritic cells.

    PubMed

    Shao, Zhifei; Gaurav, Rohit; Agrawal, Devendra K

    2015-07-01

    The role of ion channels is largely unknown in chemokine-induced migration in nonexcitable cells such as dendritic cells (DCs). Here, we examined the role of intermediate-conductance calcium-activated potassium channel (KCa3.1) and chloride channel (CLC3) in lymphatic chemokine-induced migration of DCs. The amplitude and kinetics of chemokine ligand (CCL19/CCL21)-induced Ca(2+) influx were associated with chemokine receptor 7 expression levels, extracellular-free Ca(2+) and Cl(-), and independent of extracellular K(+). Chemokines (CCL19 and CCL21) and KCa3.1 activator (1-ethyl-1,3-dihydro-2H-benzimidazol-2-one) induced plasma membrane hyperpolarization and K(+) efflux, which was blocked by 1-[(2-chlorophenyl)diphenylmethyl]-1H-pyrazole, suggesting that KCa3.1 carried larger conductance than the inward calcium release-activated calcium channel. Blockade of KCa3.1, low Cl(-) in the medium, and low dose of 4,4'-diisothiocyano-2,2'-stilbenedisulfonic acid (DIDS) impaired CCL19/CCL21-induced Ca(2+) influx, cell volume change, and DC migration. High doses of DIDS completely blocked DC migration possibly by significantly disrupting mitochondrial membrane potential. In conclusion, KCa3.1 and CLC3 are critical in human DC migration by synergistically regulating membrane potential, chemokine-induced Ca(2+) influx, and cell volume.

  2. Positive and negative regulation by SLP-76/ADAP and Pyk2 of chemokine-stimulated T-lymphocyte adhesion mediated by integrin α4β1

    PubMed Central

    Dios-Esponera, Ana; Isern de Val, Soledad; Sevilla-Movilla, Silvia; García-Verdugo, Rosa; García-Bernal, David; Arellano-Sánchez, Nohemí; Cabañas, Carlos; Teixidó, Joaquin

    2015-01-01

    Stimulation by chemokines of integrin α4β1–dependent T-lymphocyte adhesion is a crucial step for lymphocyte trafficking. The adaptor Vav1 is required for chemokine-activated T-cell adhesion mediated by α4β1. Conceivably, proteins associating with Vav1 could potentially modulate this adhesion. Correlating with activation by the chemokine CXCL12 of T-lymphocyte attachment to α4β1 ligands, a transient stimulation in the association of Vav1 with SLP-76, Pyk2, and ADAP was observed. Using T-cells depleted for SLP-76, ADAP, or Pyk2, or expressing Pyk2 kinase–inactive forms, we show that SLP-76 and ADAP stimulate chemokine-activated, α4β1-mediated adhesion, whereas Pyk2 opposes T-cell attachment. While CXCL12-promoted generation of high-affinity α4β1 is independent of SLP-76, ADAP, and Pyk2, the strength of α4β1-VCAM-1 interaction and cell spreading on VCAM-1 are targets of regulation by these three proteins. GTPase assays, expression of activated or dominant-negative Rac1, or combined ADAP and Pyk2 silencing indicated that Rac1 activation by CXCL12 is a common mediator response in SLP-76–, ADAP-, and Pyk2-regulated cell adhesion involving α4β1. Our data strongly suggest that chemokine-stimulated associations between Vav1, SLP-76, and ADAP facilitate Rac1 activation and α4β1-mediated adhesion, whereas Pyk2 opposes this adhesion by limiting Rac1 activation. PMID:26202465

  3. Lateral Mobility and Nanoscale Spatial Arrangement of Chemokine-activated α4β1 Integrins on T Cells*

    PubMed Central

    Sosa-Costa, Alberto; Isern de Val, Sol; Sevilla-Movilla, Silvia; Teixidó, Joaquin

    2016-01-01

    Chemokine stimulation of integrin α4β1-dependent T lymphocyte adhesion is a key step during lymphocyte trafficking. A central question regarding α4β1 function is how its lateral mobility and organization influence its affinity and avidity following cell stimulation with chemokines and/or ligands. Using single particle tracking and superresolution imaging approaches, we explored the lateral mobility and spatial arrangement of individual α4β1integrins on T cells exposed to different activating stimuli. We show that CXCL12 stimulation leads to rapid and transient α4β1activation, measured by induction of the activation epitope recognized by the HUTS-21 anti-β1antibody and by increased talin-β1 association. CXCL12-dependent α4β1 activation directly correlated with restricted lateral diffusion and integrin immobilization. Moreover, co-stimulation by CXCL12 together with soluble VCAM-1 potentiated integrin immobilization with a 5-fold increase in immobile integrins compared with unstimulated conditions. Our data indicate that docking by talin of the chemokine-activated α4β1 to the actin cytoskeleton favors integrin immobilization, which likely facilitates ligand interaction and increased adhesiveness. Superresolution imaging showed that the nanoscale organization of high-affinity α4β1 remains unaffected following chemokine and/or ligand addition. Instead, newly activated α4β1 integrins organize on the cell membrane as independent units without joining pre-established integrin sites to contribute to cluster formation. Altogether, our results provide a rationale to understand how the spatiotemporal organization of activated α4β1 integrins regulates T lymphocyte adhesion. PMID:27481944

  4. Retinoid X receptor alpha controls innate inflammatory responses through the up-regulation of chemokine expression.

    PubMed

    Núñez, Vanessa; Alameda, Daniel; Rico, Daniel; Mota, Rubén; Gonzalo, Pilar; Cedenilla, Marta; Fischer, Thierry; Boscá, Lisardo; Glass, Christopher K; Arroyo, Alicia G; Ricote, Mercedes

    2010-06-01

    The retinoid X receptor alpha (RXRalpha) plays a central role in the regulation of many intracellular receptor signaling pathways and can mediate ligand-dependent transcription by forming homodimers or heterodimers with other nuclear receptors. Although several members of the nuclear hormone receptor superfamily have emerged as important regulators of macrophage gene expression, the existence in vivo of an RXR signaling pathway in macrophages has not been established. Here, we provide evidence that RXRalpha regulates the transcription of the chemokines Ccl6 and Ccl9 in macrophages independently of heterodimeric partners. Mice lacking RXRalpha in myeloid cells exhibit reduced levels of CCL6 and CCL9, impaired recruitment of leukocytes to sites of inflammation, and lower susceptibility to sepsis. These studies demonstrate that macrophage RXRalpha plays key roles in the regulation of innate immunity and represents a potential target for immunotherapy of sepsis.

  5. The chemokine receptors ACKR2 and CCR2 reciprocally regulate lymphatic vessel density

    PubMed Central

    Lee, Kit M; Danuser, Renzo; Stein, Jens V; Graham, Delyth; Nibbs, Robert JB; Graham, Gerard J

    2014-01-01

    Macrophages regulate lymphatic vasculature development; however, the molecular mechanisms regulating their recruitment to developing, and adult, lymphatic vascular sites are not known. Here, we report that resting mice deficient for the inflammatory chemokine-scavenging receptor, ACKR2, display increased lymphatic vessel density in a range of tissues under resting and regenerating conditions. This appears not to alter dendritic cell migration to draining lymph nodes but is associated with enhanced fluid drainage from peripheral tissues and thus with a hypotensive phenotype. Examination of embryonic skin revealed that this lymphatic vessel density phenotype is developmentally established. Further studies indicated that macrophages and the inflammatory CC-chemokine CCL2, which is scavenged by ACKR2, are associated with this phenotype. Accordingly, mice deficient for the CCL2 signalling receptor, CCR2, displayed a reciprocal phenotype of reduced lymphatic vessel density. Further examination revealed that proximity of pro-lymphangiogenic macrophages to developing lymphatic vessel surfaces is increased in ACKR2-deficient mice and reduced in CCR2-deficient mice. Therefore, these receptors regulate vessel density by reciprocally modulating pro-lymphangiogenic macrophage recruitment, and proximity, to developing, resting and regenerating lymphatic vessels. PMID:25271254

  6. Pancreatic cancer cell migration and metastasis is regulated by chemokine-biased agonism and bioenergetic signaling

    PubMed Central

    Roy, Ishan; McAllister, Donna M.; Gorse, Egal; Dixon, Kate; Piper, Clinton T.; Zimmerman, Noah P.; Getschman, Anthony E.; Tsai, Susan; Engle, Dannielle D.; Evans, Douglas B.; Volkman, Brian F.; Kalyanaraman, Balaraman; Dwinell, Michael B.

    2015-01-01

    Patients with pancreatic ductal adenocarcinoma (PDAC) invariably succumb to metastatic disease, but the underlying mechanisms that regulate PDAC cell movement and metastasis remain little understood. In this study, we investigated the effects of the chemokine gene CXCL12, which is silenced in PDAC tumors yet is sufficient to suppress growth and metastasis when re-expressed. Chemokines like CXCL12 regulate cell movement in a biphasic pattern, with peak migration typically in the low nanomolar concentration range. Herein, we tested the hypothesis that the biphasic cell migration pattern induced by CXCL12 reflected a bias of agonist bioenergetic signaling that might be exploited to interfere with PDAC metastasis. In human and murine PDAC cell models, we observed that non-migratory doses of CXCL12 were sufficient to decrease oxidative phosphorylation and glycolytic capacity and to increase levels of phosphorylated forms of the master metabolic kinase AMPK. Those same doses of CXCL12 locked myosin light chain into a phosphorylated state, thereby decreasing F-actin polymerization and preventing cell migration in a manner dependent upon AMPK and the calcium-dependent kinase CAMKII. Notably, at elevated concentrations of CXCL12 that were insufficient to trigger chemotaxis of PDAC cells, AMPK blockade resulted in increased cell movement. In two preclinical mouse models of PDAC, administration of CXCL12 decreased tumor dissemination, supporting our hypothesis that chemokine-biased agonist signaling may offer a useful therapeutic strategy. Our results offer a mechanistic rationale for further investigation of CXCL12 as a potential therapy to prevent or treat PDAC metastasis. PMID:26330165

  7. Chemokine CXCL1-mediated neutrophil trafficking in the lung: Role of CXCR2 activation

    PubMed Central

    Sawant, Kirti V.; Xu, Renling; Cox, Robert; Hawkins, Hal; Sbrana, Elena; Kolli, Deepthi; Garofalo, Roberto P.; Rajarathnam, Krishna

    2015-01-01

    Chemokine CXCL1 and its receptor CXCR2 play a crucial role in host immune response by recruiting and activating neutrophils for microbial killing at the tissue site. Dysregulation in this process has been implicated in collateral tissue damage causing disease. CXCL1 reversibly exists as monomers and dimers, and it has been proposed that distinct monomer and dimer activities and monomer-dimer equilibrium regulate neutrophil function. However, the molecular mechanisms linking CXCL1/CXCR2 axis and neutrophil ‘beneficial’ and ‘destructive’ phenotypes are not known. In this study, we characterized neutrophil trafficking and its consequence in the mouse lung by CXCL1 WT (exists as monomer and dimer) and a non-dissociating dimer. Whereas WT, compared to dimer, was more active at low doses, both WT and dimer elicited large neutrophil efflux at high doses. Importantly, robust neutrophil recruitment elicited by WT or dimer was not detrimental to lung tissue integrity, and further, could not be correlated to surface CXCR2 levels. We conclude that CXCL1 monomer/dimer distribution and receptor interactions are highly coupled and regulate neutrophil trafficking, and that injury in the context of disease is a consequence of inappropriate CXCR2 activation at the target tissue and not due to mechanical forces exerted by neutrophils during recruitment. PMID:26138727

  8. Selective regulation of MAP kinases and Chemokine expression after ligation of ICAM-1 on human airway epithelial cells

    PubMed Central

    Krunkosky, Thomas M; Jarrett, Carla L

    2006-01-01

    Background Intercellular adhesion molecule 1 (ICAM-1) is an immunoglobulin-like cell adhesion molecule expressed on the surface of multiple cell types, including airway epithelial cells. It has been documented that cross-linking ICAM-1 on the surface of leukocytes results in changes in cellular function through outside-inside signaling; however, the effect of cross-linking ICAM-1 on the surface of airway epithelial cells is currently unknown. The objective of this study was to investigate whether or not cross-linking ICAM-1 on the surface of airway epithelial cells phosphorylated MAP kinases or stimulated chemokine expression and secretion. Methods The human lung adenocarcinoma (A549) cells and primary cultures of normal human bronchial epithelial (NHBE) cells were used in these studies. To increase ICAM-1 surface expression, cultures were stimulated with TNFα to enhance ICAM-1 surface expression. Following ICAM-1 upregulation, ICAM-1 was ligated with a murine anti-human ICAM-1 antibody and subsequently cross-linked with a secondary antibody (anti-mouse IgG(ab')2) in the presence or absence of the MAP kinase inhibitors. Following treatments, cultures were assessed for MAPK activation and chemokine gene expression and secretion. Control cultures were treated with murine IgG1 antibody or murine IgG1 antibody and anti-mouse IgG(ab')2 to illustrate specificity. Data were analyzed for significance using a one-way analysis of variance (ANOVA) with Bonferroni post-test correction for multiple comparisons, and relative gene expression was analyzed using the 2-ΔΔCT method. Results ICAM-1 cross-linking selectively phosphorylated both ERK and JNK MAP kinases as detected by western blot analysis. In addition, cross-linking resulted in differential regulation of chemokine expression. Specifically, IL-8 mRNA and protein secretion was not altered by ICAM-1 cross-linking, in contrast, RANTES mRNA and protein secretion was induced in both epithelial cultures. These events were

  9. Rac1 signaling regulates sepsis-induced pathologic inflammation in the lung via attenuation of Mac-1 expression and CXC chemokine formation.

    PubMed

    Hwaiz, Rundk; Hasan, Zirak; Rahman, Milladur; Zhang, Su; Palani, Karzan; Syk, Ingvar; Jeppsson, Bengt; Thorlacius, Henrik

    2013-08-01

    Excessive neutrophil recruitment is a major feature in septic lung damage although the signaling mechanisms behind pulmonary infiltration of neutrophils in sepsis remain elusive. In the present study, we hypothesized that Rac1 might play an important role in pulmonary neutrophil accumulation and tissue injury in abdominal sepsis. Male C57BL/6 mice were treated with Rac1 inhibitor NSC23766 (5 mg/kg) before cecal ligation and puncture (CLP). Bronchoalveolar lavage fluid and lung tissue were collected for the quantification of neutrophil recruitment and edema and CXC chemokine formation. Blood was collected for the determination of Mac-1 on neutrophils and proinflammatory compounds in plasma. Gene expression of CXC chemokines and tumor necrosis factor alpha was determined by quantitative reverse transcription-polymerase chain reaction in alveolar macrophages. Rac1 activity was increased in lungs from septic animals, and NSC23766 significantly decreased pulmonary activity of Rac1 induced by CLP. Administration of NSC23766 markedly reduced CLP-triggered neutrophil infiltration, edema formation, and tissue damage in the lung. Inhibition of Rac1 decreased CLP-induced neutrophil expression of Mac-1 and pulmonary formation of CXC chemokines. Moreover, NSC23766 abolished the sepsis-evoked elevation of messenger RNA levels of CXC chemokines and tumor necrosis factor alpha in alveolar macrophages. Rac1 inhibition decreased the CLP-induced increase in plasma levels of high mobility group protein B1 and interleukin 6, indicating a role of Rac1 in systemic inflammation. In conclusion, our results demonstrate that Rac1 signaling plays a key role in regulating pulmonary infiltration of neutrophils and tissue injury via regulation of chemokine production in the lung and Mac-1 expression on neutrophils in abdominal sepsis. Thus, targeting Rac1 activity might be a useful strategy to protect the lung in abdominal sepsis.

  10. Knock-down of CD44 regulates endothelial cell differentiation via NFκB-mediated chemokine production.

    PubMed

    Olofsson, Berit; Porsch, Helena; Heldin, Paraskevi

    2014-01-01

    A striking feature of microvascular endothelial cells is their capacity to fuse and differentiate into tubular structures when grown in three-dimensional (3D) extracellular matrices, in collagen or Matrigel, mimicking the in vivo blood vessel formation. In this study we demonstrate that human telomerase-immortalised foreskin microvascular endothelial (TIME) cells express high levels of the hyaluronan receptor CD44 and the hyaluronidase HYAL2. Knock-down of CD44 or HYAL2 resulted in an inability of TIME cells to form a tubular network, suggesting a key regulatory role of hyaluronan in controlling TIME cell tubulogenesis in 3D matrices. Knock-down of CD44 resulted in an upregulation of mRNA expression of the chemokines CXCL9 and CXCL12, as well as their receptors CXCR3 and CXCR4. This was accompanied by a defect maturation of the tubular structure network and increased phosphorylation of the inhibitor of NFκB kinase (IKK) complex and thus translocation of NFκB into the nucleus and activation of chemokine targed genes. Furthermore, the interaction between CD44 and hyaluronan determines the adhesion of breast cancer cells. In summary, our observations support the notion that the interaction between CD44 and hyaluronan regulates microvascular endothelial cell tubulogenesis by affecting the expression of cytokines and their receptors, as well as breast cancer dissemination. PMID:24614402

  11. Structural biology. Structural basis for chemokine recognition and activation of a viral G protein-coupled receptor.

    PubMed

    Burg, John S; Ingram, Jessica R; Venkatakrishnan, A J; Jude, Kevin M; Dukkipati, Abhiram; Feinberg, Evan N; Angelini, Alessandro; Waghray, Deepa; Dror, Ron O; Ploegh, Hidde L; Garcia, K Christopher

    2015-03-01

    Chemokines are small proteins that function as immune modulators through activation of chemokine G protein-coupled receptors (GPCRs). Several viruses also encode chemokines and chemokine receptors to subvert the host immune response. How protein ligands activate GPCRs remains unknown. We report the crystal structure at 2.9 angstrom resolution of the human cytomegalovirus GPCR US28 in complex with the chemokine domain of human CX3CL1 (fractalkine). The globular body of CX3CL1 is perched on top of the US28 extracellular vestibule, whereas its amino terminus projects into the central core of US28. The transmembrane helices of US28 adopt an active-state-like conformation. Atomic-level simulations suggest that the agonist-independent activity of US28 may be due to an amino acid network evolved in the viral GPCR to destabilize the receptor's inactive state. PMID:25745166

  12. Cloning and characterization of exodus, a novel beta-chemokine.

    PubMed

    Hromas, R; Gray, P W; Chantry, D; Godiska, R; Krathwohl, M; Fife, K; Bell, G I; Takeda, J; Aronica, S; Gordon, M; Cooper, S; Broxmeyer, H E; Klemsz, M J

    1997-05-01

    Chemokines are a family of related proteins that regulate leukocyte infiltration into inflamed tissue. Some chemokines such as MIP-1 alpha also inhibit hematopoietic progenitor cell proliferation. Recently, three chemokines, MIP-1 alpha, MIP-1 beta, and RANTES, have been found to significantly decrease human immunodeficiency virus production from infected T cells. We report here the cloning and characterization of a novel human chemokine termed Exodus for its chemotactic properties. This novel chemokine is distantly related to other chemokines (28% homology with MIP-1 alpha) and shares several biological activities. Exodus is expressed preferentially in lymphocytes and monocytes, and its expression is markedly upregulated by mediators of inflammation such as tumor necrosis factor or lipopolysaccharide. Purified synthetic Exodus was found to inhibit proliferation of myeloid progenitors in colony formation assays. Exodus also stimulated chemotaxis of peripheral blood mononuclear cells. The sequence homology, expression, and biological activity indicate that Exodus represents a novel divergent beta-chemokine.

  13. Estrogen, SNP-Dependent Chemokine Expression and Selective Estrogen Receptor Modulator Regulation.

    PubMed

    Ho, Ming-Fen; Bongartz, Tim; Liu, Mohan; Kalari, Krishna R; Goss, Paul E; Shepherd, Lois E; Goetz, Matthew P; Kubo, Michiaki; Ingle, James N; Wang, Liewei; Weinshilboum, Richard M

    2016-03-01

    We previously reported, on the basis of a genome-wide association study for aromatase inhibitor-induced musculoskeletal symptoms, that single-nucleotide polymorphisms (SNPs) near the T-cell leukemia/lymphoma 1A (TCL1A) gene were associated with aromatase inhibitor-induced musculoskeletal pain and with estradiol (E2)-induced TCL1A expression. Furthermore, variation in TCL1A expression influenced the downstream expression of proinflammatory cytokines and cytokine receptors. Specifically, the top hit genome-wide association study SNP, rs11849538, created a functional estrogen response element (ERE) that displayed estrogen receptor (ER) binding and increased E2 induction of TCL1A expression only for the variant SNP genotype. In the present study, we pursued mechanisms underlying the E2-SNP-dependent regulation of TCL1A expression and, in parallel, our subsequent observations that SNPs at a distance from EREs can regulate ERα binding and that ER antagonists can reverse phenotypes associated with those SNPs. Specifically, we performed a series of functional genomic studies using a large panel of lymphoblastoid cell lines with dense genomic data that demonstrated that TCL1A SNPs at a distance from EREs can modulate ERα binding and expression of TCL1A as well as the expression of downstream immune mediators. Furthermore, 4-hydroxytamoxifen or fulvestrant could reverse these SNP-genotype effects. Similar results were found for SNPs in the IL17A cytokine and CCR6 chemokine receptor genes. These observations greatly expand our previous results and support the existence of a novel molecular mechanism that contributes to the complex interplay between estrogens and immune systems. They also raise the possibility of the pharmacological manipulation of the expression of proinflammatory cytokines and chemokines in a SNP genotype-dependent fashion. PMID:26866883

  14. A lymphocyte-specific CC chemokine, secondary lymphoid tissue chemokine (SLC), is a highly efficient chemoattractant for B cells and activated T cells.

    PubMed

    Nagira, M; Imai, T; Yoshida, R; Takagi, S; Iwasaki, M; Baba, M; Tabira, Y; Akagi, J; Nomiyama, H; Yoshie, O

    1998-05-01

    Secondary lymphoid tissue chemokine (SLC) is a CC chemokine expressed mainly in lymph nodes, appendix and spleen, and specifically chemotactic for lymphocytes (Nagira et al., J. Biol. Chem. 1997. 272: 19518-19524). Here, we carried out transendothelial migration assays to determine the classes and subsets of lymphocytes migrating toward SLC. SLC attracted freshly isolated B cells with high efficiency and T cells modestly. Thus, SLC is the first CC chemokine with a strong chemotactic activity on fresh B cells. Among T cell types and subsets, SLC broadly attracted CD4+ and CD8+ cells, CD45RO- (naive) and CD45RO+ (memory) cells, and CD26high (activated) and CD26low- (resting) cells. SLC also attracted both L-selectin+ and L-selectin- subpopulations of various T cell subsets and B cells. Furthermore, mitogenic stimulation strongly enhanced migratory responses of T cells and B cells toward SLC. By in situ hybridization, SLC mRNA was detected in the cortical parafollicular regions (the T cell areas) of a lymph node and an appendix. Collectively, SLC may be a basic chemokine supporting homeostatic migration of a broad spectrum of lymphocytes into the secondary lymphoid tissues. SLC may also be involved in immune responses by inducing highly efficient migration of T and B cells following antigenic stimulation.

  15. Peroxisome proliferator-activated receptor agonists modulate neuropathic pain: a link to chemokines?

    PubMed Central

    Freitag, Caroline M.; Miller, Richard J.

    2014-01-01

    Chronic pain presents a widespread and intractable medical problem. While numerous pharmaceuticals are used to treat chronic pain, drugs that are safe for extended use and highly effective at treating the most severe pain do not yet exist. Chronic pain resulting from nervous system injury (neuropathic pain) is common in conditions ranging from multiple sclerosis to HIV-1 infection to type II diabetes. Inflammation caused by neuropathy is believed to contribute to the generation and maintenance of neuropathic pain. Chemokines are key inflammatory mediators, several of which (MCP-1, RANTES, MIP-1α, fractalkine, SDF-1 among others) have been linked to chronic, neuropathic pain in both human conditions and animal models. The important roles chemokines play in inflammation and pain make them an attractive therapeutic target. Peroxisome proliferator-activated receptors (PPARs) are a family of nuclear receptors known for their roles in metabolism. Recent research has revealed that PPARs also play a role in inflammatory gene repression. PPAR agonists have wide-ranging effects including inhibition of chemokine expression and pain behavior reduction in animal models. Experimental evidence suggests a connection between the pain ameliorating effects of PPAR agonists and suppression of inflammatory gene expression, including chemokines. In early clinical research, one PPARα agonist, palmitoylethanolamide (PEA), shows promise in relieving chronic pain. If this link can be better established, PPAR agonists may represent a new drug therapy for neuropathic pain. PMID:25191225

  16. Analysis of the antimicrobial activities of a chemokine-derived peptide (CDAP-4) on Pseudomonas aeruginosa

    SciTech Connect

    Martinez-Becerra, Francisco; Dominguez-Ramirez, Lenin; Mendoza-Hernandez, Guillermo; Lopez-Vidal, Yolanda; Soldevila, Gloria . E-mail: garciaze@servidor.unam.mx

    2007-04-06

    Chemokines are key molecules involved in the control of leukocyte trafficking. Recently, a novel function as antimicrobial proteins has been described. CCL13 is the only member of the MCP chemokine subfamily displaying antimicrobial activity. To determine Key residues involved in its antimicrobial activity, CCL13 derived peptides were synthesized and tested against several bacterial strains, including Pseudomonas aeruginosa. One of these peptides, corresponding to the C-terminal region of CCL13 (CDAP-4) displayed good antimicrobial activity. Electron microscopy studies revealed remarkable morphological changes after CDAP-4 treatment. By computer modeling, CDAP-4 in {alpha} helical configuration generated a positive electrostatic potential that extended beyond the surface of the molecule. This feature is similar to other antimicrobial peptides. Altogether, these findings indicate that the antimicrobial activity was displayed by CCL13 resides to some extent at the C-terminal region. Furthermore, CDAP-4 could be considered a good antimicrobial candidate with a potential use against pathogens including P. aeruginosa.

  17. Regulation of naïve fetal T-cell migration by the chemokines Exodus-2 and Exodus-3.

    PubMed

    Christopherson, K; Brahmi, Z; Hromas, R

    1999-08-01

    We and other workers have recently isolated three novel CC chemokines termed Exodus-1/LARC/Mip-3alpha, Exodus-2/6Ckine/SLC/TCA4, and Exodus-3/Mip-3beta/CKbeta11/ELC. These chemokines share an amino terminal Asp-Cys-Cys-Leu sequence, unique among all chemokines. They also selectively regulate migration of adult T cells. Indeed, there is evidence that Exodus-2 and -3 are critical for adult T-cell adhesion to high endothelial venules in lymph nodes, a rate-limiting step for T-cell trafficking through nodal tissue. Less is known of the factors controlling migration of naïve human fetal T cells. We tested whether these chemokines could regulate chemotaxis in cord blood T-cell populations, and compared that efficacy with normal peripheral blood adult T cells. The findings indicated that naive CD45RA+ cord blood T-cell migration is stimulated by Exodus-2 and -3, and CD4+ cord blood T cells are attracted preferentially by Exodus-2 or -3 as compared with CD8+. Exodus-2 and -3 are likely to be critical in regulating the flux of naive CD4 + fetal T-cell population of secondary lymphoid tissue.

  18. CC chemokine receptor 10 cell surface presentation in melanocytes is regulated by the novel interaction partner S100A10

    PubMed Central

    Hessner, F.; Dlugos, C. P.; Chehab, T.; Schaefer, C.; Homey, B.; Gerke, V.; Weide, T.; Pavenstädt, H.; Rescher, U.

    2016-01-01

    The superfamily of G-protein-coupled receptors (GPCR) conveys signals in response to various endogenous and exogenous stimuli. Consequently, GPCRs are the most important drug targets. CCR10, the receptor for the chemokines CCL27/CTACK and CCL28/MEC, belongs to the chemokine receptor subfamily of GPCRs and is thought to function in immune responses and tumour progression. However, there is only limited information on the intracellular regulation of CCR10. We find that S100A10, a member of the S100 family of Ca2+ binding proteins, binds directly to the C-terminal cytoplasmic tail of CCR10 and that this interaction regulates the CCR10 cell surface presentation. This identifies S100A10 as a novel interaction partner and regulator of CCR10 that might serve as a target for therapeutic intervention. PMID:26941067

  19. Bone marrow mesenchymal stem cells express a restricted set of functionally active chemokine receptors capable of promoting migration to pancreatic islets.

    PubMed

    Sordi, Valeria; Malosio, Maria Luisa; Marchesi, Federica; Mercalli, Alessia; Melzi, Raffaella; Giordano, Tiziana; Belmonte, Nathalie; Ferrari, Giuliana; Leone, Biagio Eugenio; Bertuzzi, Federico; Zerbini, Gianpaolo; Allavena, Paola; Bonifacio, Ezio; Piemonti, Lorenzo

    2005-07-15

    Bone marrow-derived mesenchymal stem cells (BM-MSCs) are stromal cells with the ability to proliferate and differentiate into many tissues. Although they represent powerful tools for several therapeutic settings, mechanisms regulating their migration to peripheral tissues are still unknown. Here, we report chemokine receptor expression on human BM-MSCs and their role in mediating migration to tissues. A minority of BM-MSCs (2% to 25%) expressed a restricted set of chemokine receptors (CXC receptor 4 [CXCR4], CX3C receptor 1 [CX3CR1], CXCR6, CC chemokine receptor 1 [CCR1], CCR7) and, accordingly, showed appreciable chemotactic migration in response to the chemokines CXC ligand 12 (CXCL12), CX3CL1, CXCL16, CC chemokine ligand 3 (CCL3), and CCL19. Using human pancreatic islets as an in vitro model of peripheral tissue, we showed that islet supernatants released factors able to attract BM-MSCs in vitro, and this attraction was principally mediated by CX3CL1 and CXCL12. Moreover, cells with features of BM-MSCs were detected within the pancreatic islets of mice injected with green fluorescent protein (GFP)-positive BM. A population of bona fide MSCs that also expressed CXCR4, CXCR6, CCR1, and CCR7 could be isolated from normal adult human pancreas. This study defines the chemokine receptor repertoire of human BM-MSCs that determines their migratory activity. Modulation of homing capacity may be instrumental for harnessing the therapeutic potential of BM-MSCs. PMID:15784733

  20. T cells respond to heat shock protein 60 via TLR2: activation of adhesion and inhibition of chemokine receptors.

    PubMed

    Zanin-Zhorov, Alexandra; Nussbaum, Gabriel; Franitza, Susanne; Cohen, Irun R; Lider, Ofer

    2003-08-01

    Soluble 60 kDa heat shock protein (HSP60) activates macrophages via TLR4. We now report that soluble HSP60 activates T cells via the innate receptor TLR2. HSP60 activated T cell adhesion to fibronectin to a degree similar to other activators: IL-2, SDF-1alpha, and RANTES. T cell type and state of activation was important; nonactivated CD45RA+ and IL-2-activated CD45RO+ T cells responded optimally (1 h) at low concentrations (0.1-1 ng/ml), but nonactivated CD45RO+ T cells required higher concentrations (approximately 1 microg/ml) of HSP60. T cell HSP60 signaling was inhibited specifically by monoclonal antibodies (mAb) to TLR2 but not by a mAb to TLR4. Indeed, T cells from mice with mutated TLR4 could still respond to HSP60, whereas Chinese hamster T cells with mutated TLR2 did not respond. The human T cell response to soluble HSP60 depended on phosphatidylinositol 3-kinase and protein kinase C signaling and involved the phosphorylation of Pyk-2. Soluble HSP60 also inhibited actin polymerization and T cell chemotaxis through extracellular matrix-like gels toward the chemokines SDF-1alpha (CXCL12) or ELC (CCL19). Exposure to HSP60 for longer times (18 h) down-regulated chemokine receptor expression: CXCR4 and CCR7. These results suggest that soluble HSP60, through TLR2-dependent interactions, can regulate T cell behavior in inflammation. PMID:12824285

  1. CCR2 and CXCR3 agonistic chemokines are differently expressed and regulated in human alveolar epithelial cells type II

    PubMed Central

    Pechkovsky, Dmitri V; Goldmann, Torsten; Ludwig, Corinna; Prasse, Antje; Vollmer, Ekkehard; Müller-Quernheim, Joachim; Zissel, Gernot

    2005-01-01

    The attraction of leukocytes from circulation to inflamed lungs depends on the activation of both the leukocytes and the resident cells within the lung. In this study we determined gene expression and secretion patterns for monocyte chemoattractant protein-1 (MCP-1/CCL2) and T-cell specific CXCR3 agonistic chemokines (Mig/CXCL9, IP-10/CXCL10, and I-TAC/CXCL11) in TNF-α-, IFN-γ-, and IL-1β-stimulated human alveolar epithelial cells type II (AEC-II). AEC-II constitutively expressed high level of CCL2 mRNA in vitro and in situ , and released CCL2 protein in vitro . Treatment of AEC-II with proinflammatory cytokines up-regulated both CCL2 mRNA expression and release of immunoreactive CCL2, whereas IFN-γ had no effect on CCL2 release. In contrast, CXCR3 agonistic chemokines were not detected in freshly isolated AEC-II or in non-stimulated epithelial like cell line A549. IFN-γ, alone or in combination with IL-1β and TNF-α resulted in an increase in CXCL10, CXCL11, and CXCL9 mRNA expression and generation of CXCL10 protein by AEC-II or A549 cells. CXCL10 gene expression and secretion were induced in dose-dependent manner after cytokine-stimulation of AEC-II with an order of potency IFN-γ>>IL-1β ≥ TNF-α. Additionally, we localized the CCL2 and CXCL10 mRNAs in human lung tissue explants by in situ hybridization, and demonstrated the selective effects of cytokines and dexamethasone on CCL2 and CXCL10 expression. These data suggest that the regulation of the CCL2 and CXCL10 expression exhibit significant differences in their mechanisms, and also demonstrate that the alveolar epithelium contributes to the cytokine milieu of the lung, with the ability to respond to locally generated cytokines and to produce potent mediators of the local inflammatory response. PMID:16033640

  2. Berberine suppresses migration of MCF-7 breast cancer cells through down-regulation of chemokine receptors

    PubMed Central

    Ahmadiankia, Naghmeh; Moghaddam, Hamid Kalalian; Mishan, Mohammad Amir; Bahrami, Ahmad Reza; Naderi-Meshkin, Hojjat; Bidkhori, Hamid Reza; Moghaddam, Maryam; Mirfeyzi, Seyed Jamal Aldin

    2016-01-01

    Objective(s): Berberine is one of the main alkaloids and it has been proven to have different pharmacological effects including inhibition of cell cycle and progression of apoptosis in various cancerous cells; however, its effects on cancer metastasis are not well known. Cancer cells obtain the ability to change their chemokine system and convert into metastatic cells. In this study, we examined the effect of berberine on breast cancer cell migration and its probable interaction with the chemokine system in cancer cells. Materials and Methods: The MCF-7 breast cancer cell line was cultured, and then, treated with berberine (10, 20, 40 and 80 μg/ml) for 24 hr. MTT assay was used in order to determine the cytotoxic effect of berberine on MCF-7 breast cancer cells. Wound healing assay was applied to determine the inhibitory effect of berberine on cell migration. Moreover, real-time quantitative PCR analysis of selected chemokine receptors was performed to determine the probable molecular mechanism underlying the effect of berberine on breast cancer cell migration. Results: The results of wound healing assay revealed that berberine decreases cell migration. Moreover, we found that the mRNA levels of some chemokine receptors were reduced after berberine treatment, and this may be the underlying mechanism for decreased cell migration. Conclusion: Our results indicate that berberine might be a potential preventive biofactor for human breast cancer metastasis by targeting chemokine receptor genes. PMID:27081456

  3. Role of chemokine RANTES in the regulation of perivascular inflammation, T-cell accumulation, and vascular dysfunction in hypertension.

    PubMed

    Mikolajczyk, Tomasz P; Nosalski, Ryszard; Szczepaniak, Piotr; Budzyn, Klaudia; Osmenda, Grzegorz; Skiba, Dominik; Sagan, Agnieszka; Wu, Jing; Vinh, Antony; Marvar, Paul J; Guzik, Bartlomiej; Podolec, Jakub; Drummond, Grant; Lob, Heinrich E; Harrison, David G; Guzik, Tomasz J

    2016-05-01

    Recent studies have emphasized the role of perivascular inflammation in cardiovascular disease. We studied mechanisms of perivascular leukocyte infiltration in angiotensin II (Ang II)-induced hypertension and their links to vascular dysfunction. Chronic Ang II infusion in mice increased immune cell content of T cells (255 ± 130 to 1664 ± 349 cells/mg; P < 0.01), M1 and M2 macrophages, and dendritic cells in perivascular adipose tissue. In particular, the content of T lymphocytes bearing CC chemokine receptor (CCR) 1, CCR3, and CCR5 receptors for RANTES chemokine was increased by Ang II (CCR1, 15.6 ± 1.5% vs. 31 ± 5%; P < 0.01). Hypertension was associated with an increase in perivascular adipose tissue expression of the chemokine RANTES (relative quantification, 1.2 ± 0.2 vs. 3.5 ± 1.1; P < 0.05), which induced T-cell chemotaxis and vascular accumulation of T cells expressing the chemokine receptors CCR1, CCR3, and CCR5. Mechanistically, RANTES(-/-) knockout protected against vascular leukocyte, and in particular T lymphocyte infiltration (26 ± 5% in wild type Ang II vs. 15 ± 4% in RANTES(-/-)), which was associated with protection from endothelial dysfunction induced by Ang II. This effect was linked with diminished infiltration of IFN-γ-producing CD8(+) and double-negative CD3(+)CD4(-)CD8(-) T cells in perivascular space and reduced vascular oxidative stress while FoxP3(+) T-regulatory cells were unaltered. IFN-γ ex vivo caused significant endothelial dysfunction, which was reduced by superoxide anion scavenging. In a human cohort, a significant inverse correlation was observed between circulating RANTES levels as a biomarker and vascular function measured as flow-mediated dilatation (R = -0.3, P < 0.01) or endothelial injury marker von Willebrand factor (R = +0.3; P < 0.01). Thus, chemokine RANTES is important in the regulation of vascular dysfunction through modulation of perivascular inflammation.-Mikolajczyk, T. P., Nosalski, R., Szczepaniak, P

  4. Role of chemokine RANTES in the regulation of perivascular inflammation, T-cell accumulation, and vascular dysfunction in hypertension

    PubMed Central

    Mikolajczyk, Tomasz P.; Nosalski, Ryszard; Szczepaniak, Piotr; Budzyn, Klaudia; Osmenda, Grzegorz; Skiba, Dominik; Sagan, Agnieszka; Wu, Jing; Vinh, Antony; Marvar, Paul J.; Guzik, Bartlomiej; Podolec, Jakub; Drummond, Grant; Lob, Heinrich E.; Harrison, David G.; Guzik, Tomasz J.

    2016-01-01

    Recent studies have emphasized the role of perivascular inflammation in cardiovascular disease. We studied mechanisms of perivascular leukocyte infiltration in angiotensin II (Ang II)-induced hypertension and their links to vascular dysfunction. Chronic Ang II infusion in mice increased immune cell content of T cells (255 ± 130 to 1664 ± 349 cells/mg; P < 0.01), M1 and M2 macrophages, and dendritic cells in perivascular adipose tissue. In particular, the content of T lymphocytes bearing CC chemokine receptor (CCR) 1, CCR3, and CCR5 receptors for RANTES chemokine was increased by Ang II (CCR1, 15.6 ± 1.5% vs. 31 ± 5%; P < 0.01). Hypertension was associated with an increase in perivascular adipose tissue expression of the chemokine RANTES (relative quantification, 1.2 ± 0.2 vs. 3.5 ± 1.1; P < 0.05), which induced T-cell chemotaxis and vascular accumulation of T cells expressing the chemokine receptors CCR1, CCR3, and CCR5. Mechanistically, RANTES−/− knockout protected against vascular leukocyte, and in particular T lymphocyte infiltration (26 ± 5% in wild type Ang II vs. 15 ± 4% in RANTES−/−), which was associated with protection from endothelial dysfunction induced by Ang II. This effect was linked with diminished infiltration of IFN-γ-producing CD8+ and double-negative CD3+CD4−CD8− T cells in perivascular space and reduced vascular oxidative stress while FoxP3+ T-regulatory cells were unaltered. IFN-γ ex vivo caused significant endothelial dysfunction, which was reduced by superoxide anion scavenging. In a human cohort, a significant inverse correlation was observed between circulating RANTES levels as a biomarker and vascular function measured as flow-mediated dilatation (R = −0.3, P < 0.01) or endothelial injury marker von Willebrand factor (R = +0.3; P < 0.01). Thus, chemokine RANTES is important in the regulation of vascular dysfunction through modulation of perivascular inflammation.—Mikolajczyk, T. P., Nosalski, R., Szczepaniak, P

  5. Critical roles of chemokine receptor CCR10 in regulating memory IgA responses in intestines.

    PubMed

    Hu, Shaomin; Yang, KangKang; Yang, Jie; Li, Ming; Xiong, Na

    2011-11-01

    Chemokine receptor CCR10 is expressed by all intestinal IgA-producing plasma cells and is suggested to play an important role in positioning these cells in the lamina propria for proper IgA production to maintain intestinal homeostasis and protect against infection. However, interfering with CCR10 or its ligand did not impair intestinal IgA production under homeostatic conditions or during infection, and the in vivo function of CCR10 in the intestinal IgA response remains unknown. We found that an enhanced generation of IgA(+) cells in isolated lymphoid follicles of intestines offset defective intestinal migration of IgA(+) cells in CCR10-KO mice, resulting in the apparently normal IgA production under homeostatic conditions and in primary response to pathogen infection. However, the compensatorily generated IgA(+) cells in CCR10-KO mice carried fewer hypermutations in their Ig heavy chain alleles than those of WT mice, indicating that their IgA repertoires are qualitatively different, which might impact the intestinal homeostasis of microflora. In addition, CCR10-deficient long-lived IgA-producing plasma cells and IgA(+) memory B cells generated against the pathogen infection could not be maintained properly in intestines. Consequently, IgA memory responses to the pathogen reinfection were severely impaired in CCR10-KO mice. These findings elucidate critical roles of CCR10 in regulating the intestinal IgA response and memory maintenance and could help in design of vaccines against intestinal and possibly other mucosal pathogens.

  6. BMP9 Crosstalk with the Hippo Pathway Regulates Endothelial Cell Matricellular and Chemokine Responses

    PubMed Central

    Young, Kira; Tweedie, Eric; Conley, Barbara; Ames, Jacquelyn; FitzSimons, MaryLynn; Brooks, Peter; Liaw, Lucy; Vary, Calvin P. H.

    2015-01-01

    Endoglin is a type III TGFβ auxiliary receptor that is upregulated in endothelial cells during angiogenesis and, when mutated in humans, results in the vascular disease hereditary hemorrhagic telangiectasia (HHT). Though endoglin has been implicated in cell adhesion, the underlying molecular mechanisms are still poorly understood. Here we show endoglin expression in endothelial cells regulates subcellular localization of zyxin in focal adhesions in response to BMP9. RNA knockdown of endoglin resulted in mislocalization of zyxin and altered formation of focal adhesions. The mechanotransduction role of focal adhesions and their ability to transmit regulatory signals through binding of the extracellular matrix are altered by endoglin deficiency. BMP/TGFβ transcription factors, SMADs, and zyxin have recently been implicated in a newly emerging signaling cascade, the Hippo pathway. The Hippo transcription coactivator, YAP1 (yes-associated protein 1), has been suggested to play a crucial role in mechanotransduction and cell-cell contact. Identification of BMP9-dependent nuclear localization of YAP1 in response to endoglin expression suggests a mechanism of crosstalk between the two pathways. Suppression of endoglin and YAP1 alters BMP9-dependent expression of YAP1 target genes CCN1 (cysteine-rich 61, CYR61) and CCN2 (connective tissue growth factor, CTGF) as well as the chemokine CCL2 (monocyte chemotactic protein 1, MCP-1). These results suggest a coordinate effect of endoglin deficiency on cell matrix remodeling and local inflammatory responses. Identification of a direct link between the Hippo pathway and endoglin may reveal novel mechanisms in the etiology of HHT. PMID:25909848

  7. BMP9 Crosstalk with the Hippo Pathway Regulates Endothelial Cell Matricellular and Chemokine Responses.

    PubMed

    Young, Kira; Tweedie, Eric; Conley, Barbara; Ames, Jacquelyn; FitzSimons, MaryLynn; Brooks, Peter; Liaw, Lucy; Vary, Calvin P H

    2015-01-01

    Endoglin is a type III TGFβ auxiliary receptor that is upregulated in endothelial cells during angiogenesis and, when mutated in humans, results in the vascular disease hereditary hemorrhagic telangiectasia (HHT). Though endoglin has been implicated in cell adhesion, the underlying molecular mechanisms are still poorly understood. Here we show endoglin expression in endothelial cells regulates subcellular localization of zyxin in focal adhesions in response to BMP9. RNA knockdown of endoglin resulted in mislocalization of zyxin and altered formation of focal adhesions. The mechanotransduction role of focal adhesions and their ability to transmit regulatory signals through binding of the extracellular matrix are altered by endoglin deficiency. BMP/TGFβ transcription factors, SMADs, and zyxin have recently been implicated in a newly emerging signaling cascade, the Hippo pathway. The Hippo transcription coactivator, YAP1 (yes-associated protein 1), has been suggested to play a crucial role in mechanotransduction and cell-cell contact. Identification of BMP9-dependent nuclear localization of YAP1 in response to endoglin expression suggests a mechanism of crosstalk between the two pathways. Suppression of endoglin and YAP1 alters BMP9-dependent expression of YAP1 target genes CCN1 (cysteine-rich 61, CYR61) and CCN2 (connective tissue growth factor, CTGF) as well as the chemokine CCL2 (monocyte chemotactic protein 1, MCP-1). These results suggest a coordinate effect of endoglin deficiency on cell matrix remodeling and local inflammatory responses. Identification of a direct link between the Hippo pathway and endoglin may reveal novel mechanisms in the etiology of HHT.

  8. The chemokine CXCL13 is a key regulator of B cell recruitment to the cerebrospinal fluid in acute Lyme neuroborreliosis

    PubMed Central

    2009-01-01

    Background The chemokine CXCL13 is known to dictate homing and motility of B cells in lymphoid tissue and has been implicated in the formation of ectopic lymphoid tissue in chronic inflammation. Whether it influences B cell trafficking during acute infection, is largely unclear. In previous studies, we showed that (I) CXCL13 levels are markedly increased in the B cell-rich cerebrospinal fluid (CSF) of patients with acute Lyme neuroborreliosis (LNB), and (II) CXCL13 is released by monocytes upon recognition of borrelial outer surface proteins by Toll-like receptor 2. Here, we assessed the role of CXCL13 - in comparison to other chemokines - in the recruitment of B cells to the CSF of patients with acute LNB. Methods Measurement of chemokines was done by ELISA. B cells were isolated from whole blood using magnetic cell separation (MACS). For migration experiments, a modified Boyden chamber assay was used and the migrated B cells were further analysed by FACS. The migration was inhibited either by preincubation of the CSF samples with neutralizing antibodies, heating to 60°C, removal of proteins >3 kDa, or by pre-treatment of the B cells with pertussis toxin. The principal statistical tests used were one-way analysis of variance and Bonferroni test (chemokine measurements) as well as paired Student's t-test (migration experiments). Results Measurements of chemokine levels revealed an increase in three of the four known major B cell chemoattractants CXCL13, CCL19 and CXCL12 in LNB CSF. The CXCL13 CSF:serum ratio, as a measure of the chemotactic gradient, was substantially higher than that of CCL19 and CXCL12. Moreover, the chemotactic activity of LNB CSF was reduced up to 56% after preincubation with a neutralizing CXCL13 antibody, while combined preincubation with antibodies against CXCL13, CCL19, and CXCL12 did not lead to further reduction. Since treatment with pertussis toxin, heating to 60°C, and removal of proteins >3 kDa abrogated the chemotactic activity

  9. Smoothing T cell roads to the tumor: Chemokine post-translational regulation.

    PubMed

    Molon, Barbara; Viola, Antonella; Bronte, Vincenzo

    2012-05-01

    We described a novel tumor-associated immunosuppressive mechanism based on post-translational modifications of chemokines by reactive nitrogen species (RNS). To overcome tumor immunosuppressive hindrances, we designed and developed a new drug, AT38, that inhibits RNS generation at the tumor site. Combinatorial approaches with AT38 boost the effectiveness of cancer immunotherapy protocols.

  10. An anti-inflammatory oligopeptide produced by Entamoeba histolytica down-regulates the expression of pro-inflammatory chemokines.

    PubMed

    Utrera-Barillas, Dolores; Velazquez, Juan R; Enciso, Antonio; Cruz, Samira Muñoz; Rico, Guadalupe; Curiel-Quesada, Everardo; Teran, Luis M; Kretschmer, Roberto R

    2003-10-01

    Axenically grown Entamoeba histolytica produces a pentapeptide (Met-Gln-Cys-Asn-Ser) with anti-inflammatory properties that, among others, inhibits the in vitro and in vivo locomotion of human monocytes, sparing polymorphonuclear leucocytes from this effect [hence the name originally given. Monocyte Locomotion Inhibitory Factor (MLIF)]. A synthetic construct of this peptide displays the same effects as the native material. We now added MLIF to resting and PMA-stimulated cells of a human monocyte cell line and measured the effect upon mRNA and protein expression of pro-inflammatory chemokines (RANTES, IP-10, MIP-1alpha, MIP-1beta, MCP-1, IL-8, I-309 and lymphotactin) and the shared CC receptor repertoire. The constitutive expression of these chemokines and the CC receptors was unaffected, whereas induced expression of MIP-1alpha, MIP-1beta, and I-309, and that of the CCR1 receptor--all involved in monocyte chemotaxis--was significantly inhibited by MLIF. This suggests that the inhibition of monocyte functions by MLIF may not only be exerted directly on these cells, but also--and perhaps foremost--through a conglomerate down-regulation of endogenous pro-inflammatory chemokines.

  11. The role of chemokines in glomerulonephritis.

    PubMed

    Wada, Takashi; Matsushima, Kouji; Kaneko, Shuichi

    2008-05-01

    Leukocyte infiltration to glomeruli plays an essential role in the pathogenesis of glomerulonephritis. Pathophysiological roles of chemokines and their cognate receptors have shed light on the detailed molecular mechanisms of leukocyte trafficking and activation both in clinical and experimental settings of glomerulonephritis. Infiltrating leukocytes and glomerular resident cells interact to promote and exacerbate glomerular injury, eventually leading to glomerulosclerosis. Further, recent studies on chemokines have expanded their universe beyond leukocyte migration to glomeruli, to include homeostasis, development and protection of resident cells in glomeruli. New insights into proteinuria have been uncovered by the regulation of chemokine system. The intervention of chemokines and their cognate receptors may have therapeutic potential to slow the progression of glomerulonephritis.

  12. Chemokine CCL2 up-regulated in the medullary dorsal horn astrocytes contributes to nocifensive behaviors induced by experimental tooth movement.

    PubMed

    Luo, Wei; Fu, Runqing; Tan, Yu; Fang, Bing; Yang, Zhi

    2014-02-01

    To test the hypothesis that the astrocytic chemokine (C-C motif) ligand 2 (CCL2) plays an important role in nocifensive behaviors after experimental tooth movement (ETM), the expression and cellular localization of CCL2 and astrocyte activation in the medullary dorsal horn (MDH) were determined by immunohistochemistry in rats. The dose-dependent effects of intrathecal C-C chemokine receptor type 2 (CCR2) antagonists on these changes in nocifensive behaviors were evaluated. Exogenous CCL2 was added to medullary dorsal horn slices to evaluate its contributory role in the induction of extracellular signal-regulated kinase (ERK) activation ex vivo. We found a significant increase in the expression of CCL2 and glial fibrillary acidic protein (GFAP), corresponding well to the nocifensive behaviors after ETM. In addition, application of recombinant CCL2 led to ERK activation, which could be attenuated effectively by pretreatment with CCL2-neutralizing antibody ex vivo. The magnitude of the nocifensive behavior could be reduced by medullary CCR2 antagonists in a dose-dependent manner. Therefore, the astrocytic CCL2 is actively involved in the development and maintenance of tooth-movement pain and thus may be a potential target for analgesics in orthodontic nocifensive responses control.

  13. Dysregulation of Chemokine/Chemokine Receptor Axes and NK Cell Tissue Localization during Diseases

    PubMed Central

    Bernardini, Giovanni; Antonangeli, Fabrizio; Bonanni, Valentina; Santoni, Angela

    2016-01-01

    Chemokines are small chemotactic molecules that play key roles in physiological and pathological conditions. Upon signaling via their specific receptors, chemokines regulate tissue mobilization and trafficking of a wide array of immune cells, including natural killer (NK) cells. Current research is focused on analyzing changes in chemokine/chemokine receptor expression during various diseases to interfere with pathological trafficking of cells or to recruit selected cell types to specific tissues. NK cells are a heterogeneous lymphocyte population comprising several subsets endowed with distinct functional properties and mainly representing distinct stages of a linear development process. Because of their different functional potential, the type of subset that accumulates in a tissue drives the final outcome of NK cell-regulated immune response, leading to either protection or pathology. Correspondingly, chemokine receptors, including CXCR4, CXCR3, and CX3CR1, are differentially expressed by NK cell subsets, and their expression levels can be modulated during NK cell activation. At first, this review will summarize the current knowledge on the contribution of chemokines to the localization and generation of NK cell subsets in homeostasis. How an inappropriate chemotactic response can lead to pathology and how chemokine targeting can therapeutically affect tissue recruitment/localization of distinct NK cell subsets will also be discussed. PMID:27766097

  14. Chemokine binding proteins encoded by pathogens.

    PubMed

    Alcami, Antonio; Saraiva, Margarida

    2009-01-01

    Chemokines are chemoattractant cytokines that play an important role in immunity. The role of chemokines against invading pathogens is emphasized by the expression of chemokine inhibitors by many pathogens. A mechanims employed by poxviruses and herpesviruses is the secretion of chemokine bindingproteins unrelated to host receptors that bind chemokines with high affinity and block their activity. Soluble chemokine binding proteins have also been identified in the human parasite Schistosoma mansoni and in ticks. The binding specificity of these inhibitors of cell migration point at chemokines that contribute to host defense mechanisms against various pathogens. Chemokine binding proteins modulate the immune response and may lead to new therapeutic approaches to treat inflamatory diseases.

  15. Apigenin suppresses migration and invasion of transformed cells through down-regulation of C-X-C chemokine receptor 4 expression

    SciTech Connect

    Wang, Lei; Kuang, Lisha; Hitron, John Andrew; Son, Young-Ok; Wang, Xin; Budhraja, Amit; Lee, Jeong-Chae; Pratheeshkumar, Poyil; Chen, Gang; Zhang, Zhuo; Luo, Jia; Shi, Xianglin

    2013-10-01

    Environmental exposure to arsenic is known to cause various cancers. There are some potential relationships between cell malignant transformation and C-X-C chemokine receptor type 4 (CXCR4) expressions. Metastasis, one of the major characteristics of malignantly transformed cells, contributes to the high mortality of cells. CXCR4 and its natural chemokine ligand C-X-C motif ligand 12 (CXCL12) play a critical role in metastasis. Therefore, identification of nutritional factors which are able to inhibit CXCR4 is important for protection from environmental arsenic-induced carcinogenesis and for abolishing metastasis of malignantly transformed cells. The present study demonstrates that apigenin (4′,5,7-trihydroxyflavone), a natural dietary flavonoid, suppressed CXCR4 expression in arsenic-transformed Beas-2B cells (B-AsT) and several other types of transformed/cancer cells in a dose- and time-dependent manner. Neither proteasome nor lysosome inhibitor had any effect in reducing the apigenin-induced down-regulation of CXCR4, indicating that apigenin-induced down-regulation of CXCR4 is not due to proteolytic degradation. The down-regulation of CXCR4 is mainly due to the inhibition of nuclear factor κB (NF-κB) transcriptional activity. Apigenin also abolished migration and invasion of transformed cells induced by CXCL12. In a xenograft mouse model, apigenin down-regulated CXCR4 expression and suppressed tumor growth. Taken together, our results show that apigenin is a novel inhibitor of CXCR4 expression. This dietary flavonoid has the potential to suppress migration and invasion of transformed cells and prevent environmental arsenic-induced carcinogenesis. - Highlights: • Apigenin has a potential in preventing environmental arsenic induced carcinogenesis. • Apigenin suppresses CXCR4 in malignant transformed cells in vitro and in vivo. • The down-regulation of CXCR4 is mainly due to inhibition of NF-κB activity.

  16. Human p38{delta} MAP kinase mediates UV irradiation induced up-regulation of the gene expression of chemokine BRAK/CXCL14

    SciTech Connect

    Ozawa, Shigeyuki; Ito, Shin; Kato, Yasumasa; Kubota, Eiro; Hata, Ryu-Ichiro

    2010-06-11

    The mitogen-activated protein kinase (MAPK) family comprises ERK, JNK, p38 and ERK5 (big-MAPK, BMK1). UV irradiation of squamous cell carcinoma cells induced up-regulation of gene expression of chemokine BRAK/CXCL14, stimulated p38 phosphorylation, and down-regulated the phosphorylation of ERK. Human p38 MAPKs exist in 4 isoforms: p38{alpha}, {beta}, {gamma} and {delta}. The UV stimulation of p38 phosphorylation was not inhibited by the presence of SB203580 or PD169316, inhibitors of p38{alpha} and {beta}, suggesting p38 phosphorylation was not dependent on these 2 isoforms and that p38{gamma} and/or {delta} was responsible for the phosphorylation. In fact, inhibition of each of these 4 p38 isoforms by the introduction of short hairpin (sh) RNAs for respective isoforms revealed that only shRNA for p38{delta} attenuated the UV-induced up-regulation of BRAK/CXCL14 gene expression. In addition, over-expression of p38 isoforms in the cells showed the association of p38{delta} with ERK1 and 2, concomitant with down-regulation of ERK phosphorylation. The usage of p38{delta} isoform by UV irradiation is not merely due to the abundance of this p38 isoform in the cells. Because serum deprivation of the cells also induced an increase in BRAK/CXCL14 gene expression, and in this case p38{alpha} and/or {beta} isoform is responsible for up-regulation of BRAK/CXCL14 gene expression. Taken together, the data indicate that the respective stress-dependent action of p38 isoforms is responsible for the up-regulation of the gene expression of the chemokine BRAK/CXCL14.

  17. Site-directed mutagenesis of the CC chemokine binding protein 35K-Fc reveals residues essential for activity and mutations that increase the potency of CC chemokine blockade.

    PubMed

    White, Gemma E; McNeill, Eileen; Christou, Ivy; Channon, Keith M; Greaves, David R

    2011-08-01

    Chemokines of the CC class are key mediators of monocyte recruitment and macrophage differentiation and have a well documented role in many inflammatory diseases. Blockade of chemokine activity is therefore an attractive target for anti-inflammatory therapy. 35K (vCCI) is a high-affinity chemokine binding protein expressed by poxviruses, which binds all human and murine CC chemokines, preventing their interaction with chemokine receptors. We developed an Fc-fusion protein of 35K with a modified human IgG1 Fc domain and expressed this construct in human embryonic kidney 293T cells. Purified 35K-Fc is capable of inhibiting CC chemokine-induced calcium flux, chemotaxis, and β-arrestin recruitment in primary macrophages and transfected cells. To elucidate the residues involved in chemokine neutralization, we performed site-directed mutagenesis of six key amino acids in 35K and expressed the mutant Fc-fusion proteins in vitro. We screened the mutants for their ability to block chemokine-induced β-arrestin recruitment in transfected cells and to inhibit primary macrophage signaling in an electric cell substrate impedance sensing assay. Using a sterile model of acute inflammation, zymosan-induced peritonitis, we confirmed that wild-type 35K-Fc can reduce monocyte recruitment, whereas one mutant (R89A) showed a more pronounced blockade of monocyte influx and another mutant (E143K) showed total loss of function. We believe that 35K-Fc will be a useful tool for exploring the role of CC chemokines in chronic inflammatory pathologies, and we have identified a higher potency form of the molecule that may have potential therapeutic applications in chronic inflammatory disease.

  18. Expression of macrophage-derived chemokine (CCL22) in atherosclerosis and regulation by histamine via the H2 receptor.

    PubMed

    Kimura, Satoshi; Tanimoto, Akihide; Wang, Ke-Yong; Shimajiri, Shohei; Guo, Xin; Tasaki, Takashi; Yamada, Sohsuke; Sasaguri, Yasuyuki

    2012-10-01

    Macrophage-derived chemokine (CCL22) is a member of the CC-family of chemokines and is synthesized by monocyte-derived macrophages and dendritic cells (DCs). In this study, we investigate the relationship between monocytes/macrophages and histamine in atherosclerosis and discover that histamine levels regulate various immunologically important molecules and influences atherosclerotic progression. Immunohistochemical analysis of human atherosclerotic lesions revealed that macrophages and DCs express CCL22. The human acute monocytic leukemia cell line (THP-1) adhered to culture plates and morphologically changed to macrophage-like cells when treated with tetradecanoylphorbol-13-acetate (TPA). Macrophage-like cells derived from THP-1 cells and cultivated peripheral blood mononuclear cells (PBMCs) show similar expression of CCL22. Gene expression of CCL22 was also detected in THP-1 cells treated with histamine and the expression of the protein produced by the CCL22 gene is similar in PBMCs and THP-1 cells. In addition, the histamine H2 receptor mediated these reactions. Our results suggest that CCL22 expression in monocytes is regulated by histamine, and that CCL22 is involved centrally in the development of human atherosclerotic lesions. In conclusion, CCL22 is a marker that is a characteristic of the monocytes/ macrophages migrating into atherosclerotic lesions and histamine plays a role in regulating its expression.

  19. Chemokines, chemokine receptors and the gastrointestinal system

    PubMed Central

    Miyazaki, Hiroshi; Takabe, Kazuaki; Yeudall, W Andrew

    2013-01-01

    The biological properties of tumor cells are known to be regulated by a multitude of cytokines and growth factors, which include epidermal growth factor receptor agonists and members of the transforming growth factor β family. Furthermore, the recent explosion of research in the field of chemokine function as mediators of tumor progression has led to the possibility that these small, immunomodulatory proteins also play key roles in carcinogenesis and may, therefore, be potential targets for novel therapeutic approaches. In this review, we will summarize recently reported findings in chemokine biology with a focus on the gastrointestinal tract. PMID:23704819

  20. Apigenin suppresses migration and invasion of transformed cells through down-regulation of C-X-C chemokine receptor 4 expression

    PubMed Central

    Wang, Lei; Kuang, Lisha; Hitron, John Andrew; Son, Young-Ok; Wang, Xin; Budhraja, Amit; Lee, Jeong-Chae; Poyil, Pratheeshkumar; Chen, Gang; Zhang, Zhuo; Luo, Jia; Shi, Xianglin

    2013-01-01

    Environmental exposure to arsenic is known to cause various cancers. There are some potential relationships between cell malignant transformation and C-X-C chemokine receptor type 4 (CXCR4) expressions. Metastasis, one of the major characteristics of malignantly transformed cells, contributes to the high mortality of cells. CXCR4 and its natural chemokine ligand C-X-C motif ligand 12 (CXCL12) play a critical role in metastasis. Therefore, identification of nutritional factors which are able to inhibit CXCR4 is important for protection from environmental arsenic-induced carcinogenesis and for abolishing metastasis of malignantly transformed cells. The present study demonstrates that apigenin (4′, 5, 7-trihydroxyflavone), a natural dietary flavonoid, suppressed CXCR4 expression in arsenic-transformed Beas-2B cells (B-AsT) and several other type of transformed/cancer cells in a dose- and time-dependent manner. Neither proteasome nor lysosome inhibitor had any effect in reducing the apigenin-induced down-regulation of CXCR4, indicating that apigenin-induced down-regulation of CXCR4 is not due to proteolytic degradation. The down-regulation of CXCR4 is mainly due to the inhibition of nuclear factor κB (NF-κB) transcriptional activity. Apigenin also abolished migration and invasion of transformed cells induced by CXCL12. In a xenograft mouse model, apigenin down-regulated CXCR4 expression and suppressed tumor growth. Taken together, our results show that apigenin is a novel inhibitor of CXCR4 expression. This dietary flavonoid has the potential to suppress migration and invasion of transformed cells and prevent environmental arsenic-induced carcinogenesis. PMID:23743303

  1. Teleost Chemokines and Their Receptors

    PubMed Central

    Bird, Steve; Tafalla, Carolina

    2015-01-01

    Chemokines are a superfamily of cytokines that appeared about 650 million years ago, at the emergence of vertebrates, and are responsible for regulating cell migration under both inflammatory and physiological conditions. The first teleost chemokine gene was reported in rainbow trout in 1998. Since then, numerous chemokine genes have been identified in diverse fish species evidencing the great differences that exist among fish and mammalian chemokines, and within the different fish species, as a consequence of extensive intrachromosomal gene duplications and different infectious experiences. Subsequently, it has only been possible to establish clear homologies with mammalian chemokines in the case of some chemokines with well-conserved homeostatic roles, whereas the functionality of other chemokine genes will have to be independently addressed in each species. Despite this, functional studies have only been undertaken for a few of these chemokine genes. In this review, we describe the current state of knowledge of chemokine biology in teleost fish. We have mainly focused on those species for which more research efforts have been made in this subject, specifically zebrafish (Danio rerio), rainbow trout (Oncorhynchus mykiss) and catfish (Ictalurus punctatus), outlining which genes have been identified thus far, highlighting the most important aspects of their expression regulation and addressing any known aspects of their biological role in immunity. Finally, we summarise what is known about the chemokine receptors in teleosts and provide some analysis using recently available data to help characterise them more clearly. PMID:26569324

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

    PubMed Central

    2014-01-01

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

  3. Duffy antigen receptor for chemokines (Darc) polymorphism regulates circulating concentrations of monocyte chemoattractant protein-1 and other inflammatory mediators

    PubMed Central

    Schnabel, Renate B.; Baumert, Jens; Barbalic, Maja; Dupuis, Josée; Ellinor, Patrick T.; Durda, Peter; Dehghan, Abbas; Bis, Joshua C.; Illig, Thomas; Morrison, Alanna C.; Jenny, Nancy S.; Keaney, John F.; Gieger, Christian; Tilley, Cathy; Yamamoto, Jennifer F.; Khuseyinova, Natalie; Heiss, Gerardo; Doyle, Margaret; Blankenberg, Stefan; Herder, Christian; Walston, Jeremy D.; Zhu, Yanyan; Vasan, Ramachandran S.; Klopp, Norman; Boerwinkle, Eric; Larson, Martin G.; Psaty, Bruce M.; Peters, Annette; Ballantyne, Christie M.; Witteman, Jacqueline C. M.

    2010-01-01

    To identify the genetic basis of circulating concentrations of monocyte chemoattractant protein-1 (MCP-1), we conducted genome-wide association analyses for MCP-1 in 3 independent cohorts (n = 9598). The strongest association was for serum MCP-1 with a nonsynonymous polymorphism, rs12075 (Asp42Gly) in DARC, the gene for Duffy antigen receptor for chemokines, a known vascular reservoir of proinflammatory cytokines (minor allele frequency, 45.6%; P < 1.0 * 10−323). This association was supported by family-based genetic linkage at a locus encompassing the DARC gene (genome-wide P = 8.0 * 10−13). Asp42Gly accounted for approximately 20% of the variability in serum MCP-1 concentrations and also was associated with serum concentrations of interleukin-8 and RANTES. While exploring a lack of association between this polymorphism and EDTA plasma MCP-1 concentrations (P = .82), we determined that both clotting and exogenous heparan sulfate (unfractionated heparin) released substantial amounts of MCP-1 from Darc. Quantitative immunoflow cytometry failed to identify meaningful Asp42Gly-associated differences in Darc expression, suggesting that a functional change is responsible for the differential cytokine binding. We conclude that Asp42Gly is a major regulator of erythrocyte Darc-mediated cytokine binding and thereby the circulating concentrations of several proinflammatory cytokines. We have also identified for the first time 2 mechanisms for the release of reservoir chemokines with possible clinical implications. PMID:20040767

  4. Activation and Recruitment of Regulatory T Cells via Chemokine Receptor Activation in Trichinella spiralis-Infected Mice

    PubMed Central

    Ahn, Jeong-Bin; Kang, Shin Ae; Kim, Dong-Hee; Yu, Hak Sun

    2016-01-01

    As most infections by the helminth parasite elicit the recruitment of CD4+CD25+Foxp3+ T (Treg) cells, many scientists have suggested that these cells could be used for the treatment of immune-mediated inflammation and associated diseases. In order to investigate the distribution and alteration of activated Treg cells, we compared the expression levels of Treg cell activation markers in the ileum and gastrocnemius tissues 1, 2, and 4 weeks after infection. The number of Treg cells was monitored using GFP-coded Foxp3 transgenic mice. In mice at 1 week after Trichinella spiralis infection, the number of activated Treg cells was higher than in the control group. In mice at 2 weeks after infection, there was a significant increase in the number of cells expressing Foxp3 and CTLA-4 when compared to the control group and mice at 1 week after infection. At 4 weeks after infection, T. spiralis was easily identifiable in nurse cells in mouse muscles. In the intestine, the expression of Gzmb and Klrg1 decreased over time and that of Capg remained unchanged for the first and second week, then decreased in the 4th week. However, in the muscles, the expression of most chemokine genes was increased due to T. spiralis infection, in particular the expression levels of Gzmb, OX40, and CTLA-4 increased until week 4. In addition, increased gene expression of all chemokine receptors in muscle, CXCR3, CCR4, CCR5, CCR9, and CCR10, was observed up until the 4th week. In conclusion, various chemokine receptors showed increased expressions combined with recruitment of Treg cells in the muscle tissue. PMID:27180574

  5. Activation and Recruitment of Regulatory T Cells via Chemokine Receptor Activation in Trichinella spiralis-Infected Mice.

    PubMed

    Ahn, Jeong-Bin; Kang, Shin Ae; Kim, Dong-Hee; Yu, Hak Sun

    2016-04-01

    As most infections by the helminth parasite elicit the recruitment of CD4(+)CD25(+)Foxp3(+) T (Treg) cells, many scientists have suggested that these cells could be used for the treatment of immune-mediated inflammation and associated diseases. In order to investigate the distribution and alteration of activated Treg cells, we compared the expression levels of Treg cell activation markers in the ileum and gastrocnemius tissues 1, 2, and 4 weeks after infection. The number of Treg cells was monitored using GFP-coded Foxp3 transgenic mice. In mice at 1 week after Trichinella spiralis infection, the number of activated Treg cells was higher than in the control group. In mice at 2 weeks after infection, there was a significant increase in the number of cells expressing Foxp3 and CTLA-4 when compared to the control group and mice at 1 week after infection. At 4 weeks after infection, T. spiralis was easily identifiable in nurse cells in mouse muscles. In the intestine, the expression of Gzmb and Klrg1 decreased over time and that of Capg remained unchanged for the first and second week, then decreased in the 4th week. However, in the muscles, the expression of most chemokine genes was increased due to T. spiralis infection, in particular the expression levels of Gzmb, OX40, and CTLA-4 increased until week 4. In addition, increased gene expression of all chemokine receptors in muscle, CXCR3, CCR4, CCR5, CCR9, and CCR10, was observed up until the 4th week. In conclusion, various chemokine receptors showed increased expressions combined with recruitment of Treg cells in the muscle tissue. PMID:27180574

  6. Chemokines and disease.

    PubMed

    Gerard, C; Rollins, B J

    2001-02-01

    We examine here several diseases that are associated with inappropriate activation of the chemokine network. Detailed comment has been restricted to pathological states for which there are compelling data either from clinical observations or animal models. These include cardiovascular disease, allergic inflammatory disease, transplantation, neuroinflammation, cancer and HIV-associated disease. Discussion focuses on therapeutic directions in which the rapidly evolving chemokine field appears to be headed. PMID:11175802

  7. Antimicrobial Activity of Chemokine CXCL10 for Dermal and Oral Microorganisms.

    PubMed

    Holdren, Grant O; Rosenthal, David J; Yang, Jianyi; Bates, Amber M; Fischer, Carol L; Zhang, Yang; Brogden, Nicole K; Brogden, Kim A

    2014-10-23

    CXCL10 (IP-10) is a small 10 kDa chemokine with antimicrobial activity. It is induced by IFN-γ, chemoattracts mononuclear cells, and promotes adhesion of T cells. Recently, we detected CXCL10 on the surface of the skin and in the oral cavity. In the current study, we used broth microdilution and radial diffusion assays to show that CXCL10 inhibits the growth of Escherichia coli, Staphylococcus aureus, Corynebacterium jeikeium, Corynebacterium striatum, and Candida albicans HMV4C, but not Corynebacterium bovis, Streptococcus mutans, Streptococcus mitis, Streptococcus sanguinis, Fusobacterium nucleatum, Aggregatibacter actinomycetemcomitans, Poryphromonas gingivalis, or C. albicans ATCC 64124. The reason for the selective antimicrobial activity is not yet known. However, antimicrobial activity of CXCL10 may be related to its composition and structure, as a cationic 98 amino acid residue molecule with 10 lysine residues, 7 arginine residues, a total net charge of +11, and a theoretical pI of 9.93. Modeling studies revealed that CXCL10 contains an α-helix at the N-terminal, three anti-parallel β-strands in the middle, and an α-helix at the C-terminal. Thus, CXCL10, when produced on the surface of the skin or in the oral cavity, likely has antimicrobial activity and may enhance innate antimicrobial and cellular responses to the presence of select commensal or opportunistic microorganisms.

  8. Stromal ETS2 Regulates Chemokine Production and Immune Cell Recruitment during Acinar-to-Ductal Metaplasia.

    PubMed

    Pitarresi, Jason R; Liu, Xin; Sharma, Sudarshana M; Cuitiño, Maria C; Kladney, Raleigh D; Mace, Thomas A; Donohue, Sydney; Nayak, Sunayana G; Qu, Chunjing; Lee, James; Woelke, Sarah A; Trela, Stefan; LaPak, Kyle; Yu, Lianbo; McElroy, Joseph; Rosol, Thomas J; Shakya, Reena; Ludwig, Thomas; Lesinski, Gregory B; Fernandez, Soledad A; Konieczny, Stephen F; Leone, Gustavo; Wu, Jinghai; Ostrowski, Michael C

    2016-09-01

    Preclinical studies have suggested that the pancreatic tumor microenvironment both inhibits and promotes tumor development and growth. Here we establish the role of stromal fibroblasts during acinar-to-ductal metaplasia (ADM), an initiating event in pancreatic cancer formation. The transcription factor V-Ets avian erythroblastosis virus E26 oncogene homolog 2 (ETS2) was elevated in smooth muscle actin-positive fibroblasts in the stroma of pancreatic ductal adenocarcinoma (PDAC) patient tissue samples relative to normal pancreatic controls. LSL-Kras(G12D/+); LSL-Trp53(R172H/+); Pdx-1-Cre (KPC) mice showed that ETS2 expression initially increased in fibroblasts during ADM and remained elevated through progression to PDAC. Conditional ablation of Ets-2 in pancreatic fibroblasts in a Kras(G12D)-driven mouse ADM model decreased the amount of ADM events. ADMs from fibroblast Ets-2-deleted animals had reduced epithelial cell proliferation and increased apoptosis. Surprisingly, fibroblast Ets-2 deletion significantly altered immune cell infiltration into the stroma, with an increased CD8+ T-cell population, and decreased presence of regulatory T cells (Tregs), myeloid-derived suppressor cells, and mature macrophages. The mechanism involved ETS2-dependent chemokine ligand production in fibroblasts. ETS2 directly bound to regulatory sequences for Ccl3, Ccl4, Cxcl4, Cxcl5, and Cxcl10, a group of chemokines that act as potent mediators of immune cell recruitment. These results suggest an unappreciated role for ETS2 in fibroblasts in establishing an immune-suppressive microenvironment in response to oncogenic Kras(G12D) signaling during the initial stages of tumor development. PMID:27659014

  9. Chemokine-Derived Peptides: Novel Antimicrobial and Antineoplasic Agents.

    PubMed

    Valdivia-Silva, Julio; Medina-Tamayo, Jaciel; Garcia-Zepeda, Eduardo A

    2015-01-01

    Chemokines are a burgeoning family of chemotactic cytokines displaying a broad array of functions such as regulation of homeostatic leukocyte traffic and development, as well as activating the innate immune system. Their role in controlling early and late inflammatory stages is now well recognized. An improper balance either in chemokine synthesis or chemokine receptor expression contributes to various pathological disorders making chemokines and their receptors a useful therapeutic target. Research in this area is progressing rapidly, and development of novel agents based on chemokine/ chemokine receptors antagonist functions are emerging as attractive alternative drugs. Some of these novel agents include generation of chemokine-derived peptides (CDP) with potential agonist and antagonist effects on inflammation, cancer and against bacterial infections. CDP have been generated mainly from N- and C-terminus chemokine sequences with subsequent modifications such as truncations or elongations. In this review, we present a glimpse of the different pharmacological actions reported for CDP and our current understanding regarding the potential use of CDP alone or as part of the novel therapies proposed in the treatment of microbial infections and cancer. PMID:26062132

  10. Chemokine-Derived Peptides: Novel Antimicrobial and Antineoplasic Agents

    PubMed Central

    Valdivia-Silva, Julio; Medina-Tamayo, Jaciel; Garcia-Zepeda, Eduardo A.

    2015-01-01

    Chemokines are a burgeoning family of chemotactic cytokines displaying a broad array of functions such as regulation of homeostatic leukocyte traffic and development, as well as activating the innate immune system. Their role in controlling early and late inflammatory stages is now well recognized. An improper balance either in chemokine synthesis or chemokine receptor expression contributes to various pathological disorders making chemokines and their receptors a useful therapeutic target. Research in this area is progressing rapidly, and development of novel agents based on chemokine/chemokine receptors antagonist functions are emerging as attractive alternative drugs. Some of these novel agents include generation of chemokine-derived peptides (CDP) with potential agonist and antagonist effects on inflammation, cancer and against bacterial infections. CDP have been generated mainly from N- and C-terminus chemokine sequences with subsequent modifications such as truncations or elongations. In this review, we present a glimpse of the different pharmacological actions reported for CDP and our current understanding regarding the potential use of CDP alone or as part of the novel therapies proposed in the treatment of microbial infections and cancer. PMID:26062132

  11. Chemokine-Derived Peptides: Novel Antimicrobial and Antineoplasic Agents.

    PubMed

    Valdivia-Silva, Julio; Medina-Tamayo, Jaciel; Garcia-Zepeda, Eduardo A

    2015-06-08

    Chemokines are a burgeoning family of chemotactic cytokines displaying a broad array of functions such as regulation of homeostatic leukocyte traffic and development, as well as activating the innate immune system. Their role in controlling early and late inflammatory stages is now well recognized. An improper balance either in chemokine synthesis or chemokine receptor expression contributes to various pathological disorders making chemokines and their receptors a useful therapeutic target. Research in this area is progressing rapidly, and development of novel agents based on chemokine/ chemokine receptors antagonist functions are emerging as attractive alternative drugs. Some of these novel agents include generation of chemokine-derived peptides (CDP) with potential agonist and antagonist effects on inflammation, cancer and against bacterial infections. CDP have been generated mainly from N- and C-terminus chemokine sequences with subsequent modifications such as truncations or elongations. In this review, we present a glimpse of the different pharmacological actions reported for CDP and our current understanding regarding the potential use of CDP alone or as part of the novel therapies proposed in the treatment of microbial infections and cancer.

  12. The chemokine SLC is expressed in T cell areas of lymph nodes and mucosal lymphoid tissues and attracts activated T cells via CCR7.

    PubMed

    Willimann, K; Legler, D F; Loetscher, M; Roos, R S; Delgado, M B; Clark-Lewis, I; Baggiolini, M; Moser, B

    1998-06-01

    Secondary lymphoid-tissue chemokine, SLC, also known as exodus-2 and 6Ckine, is a novel CC chemokine with selectivity for T lymphocytes and preferential expression in lymphoid tissues. We have studied its production, receptor usage and biological activities. High levels of SLC mRNA were detected in lymph nodes, the gastrointestinal tract and several gland tissues, but no expression was found by Northern blot analysis in freshly isolated or stimulated blood monocytes and lymphocytes, or neutrophils and eosinophils. In situ hybridization revealed constitutive expression of SLC in the T cell areas and the marginal zone of follicles in lymph nodes and the mucosa-associated lymphoid tissue, but not in B cell areas or sinuses. Comparison with immunocytochemical staining showed similarity between the in situ expression of SLC and the distribution of interdigitating dendritic cells but not with sinus-lining dendritic cells, macrophages or T lymphocytes. SLC induced chemotaxis of T lymphocytes and its activity increased considerably when the cells were conditioned with IL-2 or phytohemagglutinin (PHA). Under optimal conditions SLC had unusually high efficacy and induced the migration of up to 50 % of input T lymphocytes. SLC also induced Ca2+ mobilization in these cells. Similar responses were obtained with EBI1 ligand chemokine (ELC), and sequential stimulation with both chemokines led to cross-desensitization, suggesting that SLC acts via the ELC receptor, CCR7. This was confirmed using murine pre-B cells stably transfected with CCR7 which bound SLC with high affinity and showed chemotaxis and Ca2+ mobilization in response to both SLC and ELC. In T lymphocytes PHA and IL-2, which enhanced chemotactic responsiveness, also markedly enhanced CCR7 expression. In contrast to all known chemokine receptors, up-regulation of CCR7 by IL-2 was transient. A maximum was reached in 2-3 days and expression returned to initial levels within 8-10 days. The present study shows that SLC is

  13. Elevated autocrine chemokine ligand 18 expression promotes oral cancer cell growth and invasion via Akt activation

    PubMed Central

    Hong, Yun; Wu, Tong; Chen, Xiaobing; Xia, Juan; Cheng, Bin

    2016-01-01

    Chemokine (C-C motif) ligand 18 (CCL18) has been implicated in the pathogenesis and progression of various cancers; however, in oral squamous cell carcinoma (OSCC), the role of CCL18 is unknown. In this study, we found that CCL18 was overexpressed in primary OSCC tissues and was associated with an advanced clinical stage. CCL18 was found in both the cytoplasm and cell membrane of OSCC cells and was predominantly produced by cancer epithelial cells, as opposed to tumor-infiltrating macrophages. In vitro studies indicated that the effects of endogenous CCL18 on OSCC cell growth, migration, and invasion could be blocked by treatment with a neutralizing anti-CCL18 antibody or CCL18 knockdown, while exogenous recombinant CCL18 (rCCL18) rescued those effects. Akt was activated in rCCL18-treated OSCC cells, while LY294002, a pan-PI3K inhibitor, abolished both endogenous and exogenous CCL18-induced OSCC cell invasion. In vivo, LY294002 treatment attenuated rCCL18-induced OSCC cell growth. Our results indicate that CCL18 acts in an autocrine manner via Akt activation to stimulate OSCC cell growth and invasion during OSCC progression. They also provide a potential therapeutic target for the treatment of oral cancer. PMID:26919103

  14. Stress-induced production of chemokines by hair follicles regulates the trafficking of dendritic cells in skin

    PubMed Central

    Nagao, Keisuke; Kobayashi, Tetsuro; Moro, Kazuyo; Ohyama, Manabu; Adachi, Takeya; Kitashima, Daniela Y; Ueha, Satoshi; Horiuchi, Keisuke; Tanizaki, Hideaki; Kabashima, Kenji; Kubo, Akiharu; Cho, Young-hun; Clausen, Björn E; Matsushima, Kouji; Suematsu, Makoto; Furtado, Glaucia C; Lira, Sergio A; Farber, Joshua M; Udey, Mark C; Amagai, Masayuki

    2014-01-01

    Langerhans cells (LCs) are epidermal dendritic cells with incompletely understood origins that associate with hair follicles for unknown reasons. Here we show that in response to external stress, mouse hair follicles recruited Gr-1hi monocyte-derived precursors of LCs whose epidermal entry was dependent on the chemokine receptors CCR2 and CCR6, whereas the chemokine receptor CCR8 inhibited the recruitment of LCs. Distinct hair-follicle regions had differences in their expression of ligands for CCR2 and CCR6. The isthmus expressed the chemokine CCL2; the infundibulum expressed the chemokine CCL20; and keratinocytes in the bulge produced the chemokine CCL8, which is the ligand for CCR8. Thus, distinct hair-follicle keratinocyte subpopulations promoted or inhibited repopulation with LCs via differences in chemokine production, a feature also noted in humans. Pre-LCs failed to enter hairless skin in mice or humans, which establishes hair follicles as portals for LCs. PMID:22729248

  15. PI3K{gamma} activation by CXCL12 regulates tumor cell adhesion and invasion

    SciTech Connect

    Monterrubio, Maria; Mellado, Mario; Carrera, Ana C.

    2009-10-16

    Tumor dissemination is a complex process, in which certain steps resemble those in leukocyte homing. Specific chemokine/chemokine receptor pairs have important roles in both processes. CXCL12/CXCR4 is the most commonly expressed chemokine/chemokine receptor pair in human cancers, in which it regulates cell adhesion, extravasation, metastatic colonization, angiogenesis, and proliferation. All of these processes require activation of signaling pathways that include G proteins, phosphatidylinositol-3 kinase (PI3K), JAK kinases, Rho GTPases, and focal adhesion-associated proteins. We analyzed these pathways in a human melanoma cell line in response to CXCL12 stimulation, and found that PI3K{gamma} regulates tumor cell adhesion through mechanisms different from those involved in cell invasion. Our data indicate that, following CXCR4 activation after CXCL12 binding, the invasion and adhesion processes are regulated differently by distinct downstream events in these signaling cascades.

  16. The chemokine receptor CCR1 is constitutively active, which leads to G protein-independent, β-arrestin-mediated internalization.

    PubMed

    Gilliland, C Taylor; Salanga, Catherina L; Kawamura, Tetsuya; Trejo, JoAnn; Handel, Tracy M

    2013-11-01

    Activation of G protein-coupled receptors by their associated ligands has been extensively studied, and increasing structural information about the molecular mechanisms underlying ligand-dependent receptor activation is beginning to emerge with the recent expansion in GPCR crystal structures. However, some GPCRs are also able to adopt active conformations in the absence of agonist binding that result in the initiation of signal transduction and receptor down-modulation. In this report, we show that the CC-type chemokine receptor 1 (CCR1) exhibits significant constitutive activity leading to a variety of cellular responses. CCR1 expression is sufficient to induce inhibition of cAMP formation, increased F-actin content, and basal migration of human and murine leukocytes. The constitutive activity leads to basal phosphorylation of the receptor, recruitment of β-arrestin-2, and subsequent receptor internalization. CCR1 concurrently engages Gαi and β-arrestin-2 in a multiprotein complex, which may be accommodated by homo-oligomerization or receptor clustering. The data suggest the presence of two functional states for CCR1; whereas receptor coupled to Gαi functions as a canonical GPCR, albeit with high constitutive activity, the CCR1·β-arrestin-2 complex is required for G protein-independent constitutive receptor internalization. The pertussis toxin-insensitive uptake of chemokine by the receptor suggests that the CCR1·β-arrestin-2 complex may be related to a potential scavenging function of the receptor, which may be important for maintenance of chemokine gradients and receptor responsiveness in complex fields of chemokines during inflammation.

  17. Milligram Production and Biological Activity Characterization of the Human Chemokine Receptor CCR3

    PubMed Central

    Li, Renmin; Wang, Xiaoqiang; Lao, Jun; Huang, Fang

    2013-01-01

    Human chemokine receptor CCR3 (hCCR3) belongs to the G protein-coupled receptors (GPCRs) superfamily of membrane proteins and plays major roles in allergic diseases and angiogenesis. In order to study the structural and functional mechanism of hCCR3, it is essential to produce pure protein with biological functions on a milligram scale. Here we report the expression of hCCR3 gene in a tetracycline-inducible stable mammalian cell line. A cell clone with high hCCR3 expression was selected from 46 stably transfected cell clones and from this cell line pure hCCR3 on a milligram scale was obtained after two-step purification. Circular dichroism spectrum with a characteristic shape and magnitude for α-helix indicated proper folding of hCCR3 after purification. The biological activity of purified hCCR3 was verified by its high binding affinity with its endogenous ligands CCL11 and CCL24, with KD in the range of 10−8 M to 10−6 M. PMID:23755240

  18. Non-canonical NFκB activation promotes chemokine expression in podocytes

    PubMed Central

    Valiño-Rivas, Lara; Gonzalez-Lafuente, Laura; Sanz, Ana B.; Ruiz-Ortega, Marta; Ortiz, Alberto; Sanchez-Niño, Maria D.

    2016-01-01

    TNF-like weak inducer of apoptosis (TWEAK) receptor Fn14 is expressed by podocytes and Fn14 deficiency protects from experimental proteinuric kidney disease. However, the downstream effectors of TWEAK/Fn14 in podocytes are poorly characterized. We have explored TWEAK activation of non-canonical NFκB signaling in cultured podocytes. In cultured podocytes, TWEAK increased the expression of the chemokines CCL21, CCL19 and RANTES in a time-dependent manner. The inhibitor of canonical NFκB activation parthenolide inhibited the CCL19 and the early RANTES responses, but not the CCL21 or late RANTES responses. In this regard, TWEAK induced non-canonical NFκB activation in podocytes, characterized by NFκB2/p100 processing to NFκB2/p52 and nuclear migration of RelB/p52. Silencing by a specific siRNA of NIK, the upstream kinase of the non-canonical NFκB pathway, prevented CCL21 upregulation but did not modulate CCL19 or RANTES expression in response to TWEAK, thus establishing CCL21 as a non-canonical NFκB target in podocytes. Increased kidney Fn14 and CCL21 expression was also observed in rat proteinuric kidney disease induced by puromycin, and was localized to podocytes. In conclusion, TWEAK activates the non-canonical NFκB pathway in podocytes, leading to upregulation of CCL21 expression. The non-canonical NFκB pathway should be explored as a potential therapeutic target in proteinuric kidney disease. PMID:27353019

  19. A strategy to discover decoy chemokine ligands with an anti-inflammatory activity

    PubMed Central

    Abboud, Dayana; Daubeuf, François; Do, Quoc Tuan; Utard, Valérie; Villa, Pascal; Haiech, Jacques; Bonnet, Dominique; Hibert, Marcel; Bernard, Philippe; Galzi, Jean-Luc; Frossard, Nelly

    2015-01-01

    Excessive signaling by chemokines has been associated with chronic inflammation or cancer, thus attracting substantial attention as promising therapeutic targets. Inspired by chemokine-clearing molecules shaped by pathogens to escape the immune system, we designed a generic screening assay to discover chemokine neutralizing molecules (neutraligands) and unambiguously distinguish them from molecules that block the receptor (receptor antagonists). This assay, called TRIC-r, combines time-resolved intracellular calcium recordings with pre-incubation of bioactive compounds either with the chemokine or the receptor-expressing cells. We describe here the identification of high affinity neutraligands of CCL17 and CCL22, two chemokines involved in the Th2-type of lung inflammation. The decoy molecules inhibit in vitro CCL17- or CCL22-induced intracellular calcium responses, CCR4 endocytosis and human T cell migration. In vivo, they inhibit inflammation in a murine model of asthma, in particular the recruitment of eosinophils, dendritic cells and CD4+T cells. Altogether, we developed a successful strategy to discover as new class of pharmacological tools to potently control cell chemotaxis in vitro and in vivo. PMID:26442456

  20. CXC chemokines connective tissue activating peptide-III and neutrophil activating peptide-2 are heparin/heparan sulfate-degrading enzymes.

    PubMed

    Hoogewerf, A J; Leone, J W; Reardon, I M; Howe, W J; Asa, D; Heinrikson, R L; Ledbetter, S R

    1995-02-17

    Heparan sulfate proteoglycans at cell surfaces or in extracellular matrices bind diverse molecules, including growth factors and cytokines, and it is believed that the activities of these molecules may be regulated by the metabolism of heparan sulfate. In this study, purification of a heparan sulfate-degrading enzyme from human platelets led to the discovery that the enzymatic activity residues in at least two members of the platelet basic protein (PBP) family known as connective tissue activating peptide-III (CTAP-III) and neutrophil activating peptide-2. PBP and its N-truncated derivatives, CTAP-III and neutrophil activating peptide-2, are CXC chemokines, a group of molecules involved in inflammation and wound healing. SDS-polyacrylamide gel electrophoresis analysis of the purified heparanase resulted in a single broad band at 8-10 kDa, the known molecular weight of PBP and its truncated derivatives. Gel filtration chromatography of heparanase resulted in peaks of activity corresponding to monomers, dimers, and tetramers; these higher order aggregates are known to form among the chemokines. N-terminal sequence analysis of the same preparation indicated that only PBP and truncated derivatives were present, and commercial CTAP-III from three suppliers had heparanase activity. Antisera produced in animals immunized with a C-terminal synthetic peptide of PBP inhibited heparanase activity by 95%, compared with activity of the purified enzyme in the presence of the preimmune sera. The synthetic peptide also inhibited heparanase by 95% at 250 microM, compared to the 33% inhibition of heparanase activity by two other peptides. The enzyme was determined to be an endoglucosaminidase, and it degraded both heparin and heparan sulfate with optimal activity at pH 5.8. Chromatofocusing of the purified heparanase resulted in two protein peaks: an inactive peak at pI7.3, and an active peak at pI 4.8-5.1. Sequence analysis showed that the two peaks contained identical protein

  1. Andrographolide inhibits prostate cancer by targeting cell cycle regulators, CXCR3 and CXCR7 chemokine receptors.

    PubMed

    Mir, Hina; Kapur, Neeraj; Singh, Rajesh; Sonpavde, Guru; Lillard, James W; Singh, Shailesh

    2016-01-01

    Despite state of the art cancer diagnostics and therapies offered in clinic, prostate cancer (PCa) remains the second leading cause of cancer-related deaths. Hence, more robust therapeutic/preventive regimes are required to combat this lethal disease. In the current study, we have tested the efficacy of Andrographolide (AG), a bioactive diterpenoid isolated from Andrographis paniculata, against PCa. This natural agent selectively affects PCa cell viability in a dose and time-dependent manner, without affecting primary prostate epithelial cells. Furthermore, AG showed differential effect on cell cycle phases in LNCaP, C4-2b and PC3 cells compared to retinoblastoma protein (RB(-/-)) and CDKN2A lacking DU-145 cells. G2/M transition was blocked in LNCaP, C4-2b and PC3 after AG treatment whereas DU-145 cells failed to transit G1/S phase. This difference was primarily due to differential activation of cell cycle regulators in these cell lines. Levels of cyclin A2 after AG treatment increased in all PCa cells line. Cyclin B1 levels increased in LNCaP and PC3, decreased in C4-2b and showed no difference in DU-145 cells after AG treatment. AG decreased cyclin E2 levels only in PC3 and DU-145 cells. It also altered Rb, H3, Wee1 and CDC2 phosphorylation in PCa cells. Intriguingly, AG reduced cell viability and the ability of PCa cells to migrate via modulating CXCL11 and CXCR3 and CXCR7 expression. The significant impact of AG on cellular and molecular processes involved in PCa progression suggests its potential use as a therapeutic and/or preventive agent for PCa. PMID:27029529

  2. Interleukin-25-induced chemokines and interleukin-6 release from eosinophils is mediated by p38 mitogen-activated protein kinase, c-Jun N-terminal kinase, and nuclear factor-kappaB.

    PubMed

    Wong, Chun K; Cheung, Phyllis F Y; Ip, Wai K; Lam, Christopher W K

    2005-08-01

    Interleukin (IL)-25, a novel Th2 cytokine, is capable of amplifying allergic inflammation. We investigated the modulation of nuclear factor (NF)-kappaB and mitogen-activated protein kinases (MAPK) pathways in IL-25-activated eosinophils, the principal effector cells of allergic inflammation, for the in vitro release of chemokines including monocyte chemoattractant protein-1 (MCP-1), IL-8, and macrophage inflammatory protein (MIP)-1alpha, and inflammatory cytokine IL-6. Gene expression of chemokines and IL-6 was evaluated by RT-PCR, and concentrations of chemokines and cytokine were measured by cytokine protein array, cytometric bead array, and enzyme-linked immunosorbent assay. NF-kappaB, c-Jun amino-terminal kinase (JNK), and p38 MAPK activities in eosinophils were assessed by electrophoretic mobility shift assay and Western blot. IL-25 was found to upregulate the gene expression of chemokines MCP-1, MIP-1alpha, and IL-8, and cytokine IL-6, in eosinophils, and to significantly increase the release of the above chemokines and IL-6 from eosinophils. IL-25 could also activate the JNK, p38 MAPK, and NF-kappaB activities of eosinophils, while inhibitor of IkappaB-alpha phosphorylation (BAY11-7082), JNK (SP600125), and p38 MAPK (SB203580) could suppress the release of IL-8, MIP-1alpha, MCP-1, and IL-6. Together, the above results showed that the induction of MCP-1, MIP-1alpha, IL-8, and IL-6 in IL-25-activated eosinophils are regulated by JNK, p38 MAPK, and NF-kappaB pathways.

  3. Stability of cytokines, chemokines and soluble activation markers in unprocessed blood stored under different conditions

    PubMed Central

    Aziz, Najib; Detels, Roger; Quint, Joshua J.; Li, Qian; Gjertson, David; Butch, Anthony W.

    2016-01-01

    Background Biomarkers such as cytokines, chemokines, and soluble activation markers can be unstable when processing of blood is delayed. The stability of various biomarkers in serum and plasma was investigated when unprocessed blood samples were stored for up to 24 h at room and refrigerator temperature. Methods Blood was collected from 16 healthy volunteers. Unprocessed serum, EDTA and heparinized blood was stored at room (20–25 °C) and refrigerator temperature (4–8 °C) for 0.5, 2, 4, 6, 8, and 24 h after collection before centrifugation and separation of serum and plasma. Samples were batch tested for various biomarkers using commercially available immunoassays. Statistically significant changes were determined using the generalized estimating equation. Results IFN-γ, sIL-2Rα, sTNF-RII and β2-microglobulin were stable in unprocessed serum, EDTA and heparinized blood samples stored at either room or refrigerator temperature for up to 24 h. IL-6, TNF-α, MIP-1β and RANTES were unstable in heparinized blood at room temperature; TNF-α, and MIP-1β were unstable in unprocessed serum at room temperature; IL-12 was unstable in unprocessed serum at refrigerator temperature; and neopterin was unstable in unprocessed EDTA blood at room temperature. IL-1ra was stable only in unprocessed serum at room temperature. Conclusion All the biomarkers studied, with the exception of IL-1ra, were stable in unprocessed EDTA blood stored at refrigerator temperature for 24 h. This indicates that blood for these biomarkers should be collected in EDTA and if delays in processing are anticipated the unseparated blood should be stored at refrigerator temperature until processing. PMID:27208752

  4. Chemokines and cardiovascular risk.

    PubMed

    Aukrust, Pål; Halvorsen, Bente; Yndestad, Arne; Ueland, Thor; Øie, Erik; Otterdal, Kari; Gullestad, Lars; Damås, Jan K

    2008-11-01

    Based on the importance of inflammation in atherogenesis, recent work has focused on whether plasma markers of inflammation can noninvasively diagnose and prognosticate atherosclerotic disorders. Although several studies support an important pathogenic role of chemokines in atherosclerosis, potentially representing attractive therapeutic targets in atherosclerotic disorders, this does not necessarily mean that chemokines are suitable parameters for risk prediction. In fact, the ability to reflect upstream inflammatory activity, stable levels in individuals, and high stability of the actual protein (eg, long half-life and negligible circadian variation) are additional important criteria for an ideal biomarker in cardiovascular disease. Although plasma/serum levels of certain chemokines (eg, interleukin- 8/CXCL8 and monocyte chemoattractant protein-1/CCL2) have shown to be predictive for future cardiac events in some studies, their role as clinical biomarkers is unclear, and their ability to predict subclinical atherosclerosis has been disappointing. Further prospective studies, including a larger number of patients, are needed to make any firm conclusion. Based on the participation of several chemokines in atherogenesis, it is possible that in the future, combined measurements of multiple chemokines could reveal as a "signature of disease" that can serve as a highly accurate method to assess for the presence of atherosclerotic disease. PMID:18669888

  5. Molecular identification and expression analysis of the CC chemokine gene in rock bream (Oplegnathus fasciatus) and the biological activity of the recombinant protein.

    PubMed

    Kim, Ju-Won; Kim, Eun-Gyeong; Kim, Do-Hyung; Shim, Sang Hee; Park, Chan-Il

    2013-03-01

    We identified the CC chemokine cDNA designated as RbCC1 (CC chemokine 1 in rock bream, Oplegnathus fasciatus), which was isolated using expressed sequence tag (EST) analysis of a lipopolysaccharide (LPS)-stimulated rock bream liver cDNA library. The full-length RbCC1 cDNA (850 bp) contained an open reading frame (ORF) of 366 bp encoding 122 amino acids. Results from our phylogenetic analysis demonstrated that the RbCC1 was closest relationship to the orange-spotted grouper and Mi-iyu croaker CC chemokines located within the fish CC chemokine group. RbCC1 was significantly expressed in the intestine, spleen, liver, and PBLs (peripheral blood leukocytes). Rock bream PBLs were stimulated with several mitogens, LPS and Con A/PMA which significantly induced the expression of RbCC1 mRNA in the PBLs. The RbCC1 mRNA expression in several tissues under conditions of bacterial and viral challenge was examined. The experimental challenge revealed that the kidney and spleen of fish infected with Streptococcus iniae showed the most significant increases in RbCC1 expression compared to the control. In the case of RSIV infection, the RbCC1 mRNA expression was markedly up-regulated in the liver. In this study, recombinant RbCC1 (approximately 53 kDa) was produced using an Escherichia coli expression system followed by purification. Subsequently, the addition of purified rRbCC1 was examined to investigate the impact on the proliferative and chemotactic activity on kidney leukocytes from rock bream. The results demonstrated that the rRbCC1 induces significant biological activity on kidney leukocyte proliferation and attraction at concentrations in the range of 10-300 μg/mL and suggests that rRbCC1 could be utilized as an immune-stimulant and/or molecular adjuvant to enhance the immune effects of vaccines.

  6. Heme oxygenase-1 induction alters chemokine regulation and ameliorates human immunodeficiency virus-type-1 infection in lipopolysaccharide-stimulated macrophages

    SciTech Connect

    Zhou, Zhao-Hua; Kumari, Namita; Nekhai, Sergei; Clouse, Kathleen A.; Wahl, Larry M.; Yamada, Kenneth M.; Dhawan, Subhash

    2013-06-07

    Highlights: •Lipopolysaccharide stimulation of heme oxygenase-1 (HO-1) ameliorated HIV-1 infection of primary human macrophages. •The partial protection by HO-1 against HIV infection was associated with induction of chemokines such as MIP1α and MIP1β. •This mechanism explains lipopolysaccharide-stimulated HO-1-mediated inhibition of HIV-1 infection of macrophages. -- Abstract: We have elucidated a putative mechanism for the host resistance against HIV-1 infection of primary human monocyte-derived macrophages (MDM) stimulated with lipopolysaccharide (LPS). We show that LPS-activated MDM both inhibited HIV-1 entry into the cells and were refractory to post-entry productive viral replication. LPS-treated cells were virtually negative for mature virions as revealed by transmission electron microscopy. LPS activation of MDM markedly enhanced the expression of heme oxygenase-1 (HO-1), a potent inducible cytoprotective enzyme. Increased HO-1 expression was accompanied by elevated production of macrophage inflammatory chemokines (MIP1α and MIP1β) by LPS-activated MDM, significantly decreased surface chemokine receptor-5 (CCR-5) expression, and substantially reduced virus replication. Treatment of cells with HO-1 inhibitor SnPP IX (tin protoporphyrin IX) attenuated the LPS-mediated responses, HIV-1 replication and secretion of MIP1α, MIP1β, and LD78β chemokines with little change in surface CCR-5 expression. These results identify a novel role for HO-1 in the modulation of host immune response against HIV infection of MDM.

  7. C-terminal clipping of chemokine CCL1/I-309 enhances CCR8-mediated intracellular calcium release and anti-apoptotic activity.

    PubMed

    Denis, Catherine; Deiteren, Kathleen; Mortier, Anneleen; Tounsi, Amel; Fransen, Erik; Proost, Paul; Renauld, Jean-Christophe; Lambeir, Anne-Marie

    2012-01-01

    Carboxypeptidase M (CPM) targets the basic amino acids arginine and lysine present at the C-terminus of peptides or proteins. CPM is thought to be involved in inflammatory processes. This is corroborated by CPM-mediated trimming and modulation of inflammatory factors, and expression of the protease in inflammatory environments. Since the function of CPM in and beyond inflammation remains mainly undefined, the identification of natural substrates can aid in discovering the (patho)physiological role of CPM. CCL1/I-309, with its three C-terminal basic amino acids, forms a potential natural substrate for CPM. CCL1 plays a role not only in inflammation but also in apoptosis, angiogenesis and tumor biology. Enzymatic processing differently impacts the biological activity of chemokines thereby contributing to the complex regulation of the chemokine system. The aim of the present study was to investigate whether (i) CCL1/I-309 is prone to trimming by CPM, and (ii) the biological activity of CCL1 is altered after C-terminal proteolytic processing. CCL1 was identified as a novel substrate for CPM in vitro using mass spectrometry. C-terminal clipping of CCL1 augmented intracellular calcium release mediated by CCR8 but reduced the binding of CCL1 to CCR8. In line with the higher intracellular calcium release, a pronounced increase of the anti-apoptotic activity of CCL1 was observed in the BW5147 cellular model. CCR8 signaling, CCR8 binding and anti-apoptotic activity were unaffected when CPM was exposed to the carboxypeptidase inhibitor DL-2-mercaptomethyl-3-guanidino-ethylthiopropanoic acid. The results of this study suggest that CPM is a likely candidate for the regulation of biological processes relying on the CCL1-CCR8 system. PMID:22479563

  8. Histamine and prostaglandin E2 up-regulate the production of Th2-attracting chemokines (CCL17 and CCL22) and down-regulate IFN-γ-induced CXCL10 production by immature human dendritic cells

    PubMed Central

    McIlroy, Anne; Caron, Gersende; Blanchard, Simon; Frémaux, Isabelle; Duluc, Dorothée; Delneste, Yves; Chevailler, Alain; Jeannin, Pascale

    2006-01-01

    Effector memory T helper 2 (Th2) cells that accumulate in target organs (i.e. skin or bronchial mucosa) have a central role in the pathogenesis of allergic disorders. To date, the factors that selectively trigger local production of Th2-attracting chemokines remain poorly understood. In mucosa, at the sites of allergen entry, immature dendritic cells (DC) are in close contact with mast cells. Histamine and prostaglandin E2 (PGE2) are two mediators released by allergen-activated mast cells that favour the polarization of maturing DC into Th2-polarizing cells. We analysed here the effects of histamine and PGE2 on the prototypic, Th2-(CCL17, CCL22) versus Th1-(CXCL10) chemokine production by human DC. We report that histamine and PGE2 dose-dependently up-regulate CCL17 and CCL22 by monocyte-derived immature DC. These effects were potentiated by tumour necrosis factor-α, still observed in the presence of the Th1-cytokine interferon-γ (IFN-γ) and abolished by the immunomodulatory cytokine interleukin-10. In addition, histamine and PGE2 down-regulated IFN-γ-induced CXCL10 production by monocyte-derived DC. These properties of histamine and PGE2 were observed at the transcriptional level and were mediated mainly through H2 receptors for histamine and through EP2 and EP4 receptors for PGE2. Finally, histamine and PGE2 also up-regulated CCL17 and CCL22 and decreased IFN-γ-induced CXCL10 production by purified human myeloid DC. In conclusion, these data show that, in addition to polarizing DC into mature cells that promote naïve T-cell differentiation into Th2 cells, histamine and PGE2 may act on immature DC to trigger local Th2 cell recruitment through a selective control of Th1/Th2-attracting chemokine production, thereby contributing to maintain a microenvironment favourable to persistent immunoglobulin E synthesis. PMID:16556265

  9. Glia maturation factor modulates β-amyloid-induced glial activation, inflammatory cytokine/chemokine production and neuronal damage

    PubMed Central

    Zaheer, Asgar; Zaheer, Smita; Thangavel, Ramasamy; Wu, Yanghong; Sahu, Shailendra K.; Yang, Baoli

    2008-01-01

    Glia maturation factor (GMF), discovered and characterized in our laboratory, is a highly conserved protein primarily localized in mammalian central nervous system. Previously we demonstrated that GMF is required in the induced production of proinflammatory cytokines and chemokines in brain cells. We now report that ventricular infusion of human amyloid beta peptide1-42 (Aβ1-42) in mouse brain caused glial activation and large increases in the levels of GMF as well as induction of inflammatory cytokine/chemokine known for launching the neuro inflammatory cascade in Alzheimer’s disease (AD). To test the hypothesis that GMF is involved in the pathogenesis of AD, we infused Aβ1-42 in the brain of GMF-deficient (GMF-KO) mice, recently prepared in our laboratory. GMF-deficient mice showed reduced glial activation and significantly suppressed proinflammatory cytokine/chemokine production following Aβ infusion compared to wild type (Wt) mice. The decrease in glial activation in the GMF-KO mice is also associated with significant reduction in Aβ induced loss of pre-synaptic marker, synaptophysin, and post-synaptic density protein-95 (PSD 95). We also examined the potential relationship between GMF or lack of it with learning and memory using the T-maze, Y-maze, and water maze, hippocampal-dependent spatial memory tasks. Our results show that memory retention was improved in GMF-KO mice compared to Wt controls following Aβ infusion. Diminution of these Aβ1-42 effects in primary cultures of GMF-KO astrocyte and microglia were reversed by reconstituted expression of GMF. Taken together, our results indicate a novel mediatory role of GMF in neuro-inflammatory pathway of Aβ and its pro-inflammatory functions. PMID:18395194

  10. Traditional herbal formula Jakyakgamcho-tang (Paeonia lactiflora and Glycyrrhiza uralensis) impairs inflammatory chemokine production by inhibiting activation of STAT1 and NF-κB in HaCaT cells.

    PubMed

    Jeong, Soo-Jin; Lim, Hye-Sun; Seo, Chang-Seob; Kim, Jung-Hoon; Jin, Seong-Eun; Yoo, Sae-Rom; Shin, Hyeun-Kyoo

    2015-02-15

    A traditional herbal formula Jakyakgamcho-tang (JYGCT; Paeonia lactiflora and Glycyrrhiza uralensis) has been used for treatment of backache, muscle pain, acute abdominal pain, neuralgia, bronchial asthma, and painful peripheral neuropathy in Oriental medicine. We report on our experiments using the HaCaT human keratinocyte cell line showing that a traditional herbal formula JYGCT has inhibitory effects on inflammatory responses in skin. Stimulation with tumour necrosis factor-alpha (TNF-α) and interferon-gamma (IFN-γ) caused a significant increase in the production of the following chemokines: thymus- and activation-regulated chemokine (TARC)/CCL17; macrophage-derived chemokine (MDC)/CCL22; regulated on activation, normal T-cell expressed and secreted (RANTES)/CCL5; and interleukin-8 (IL-8) in HaCaT cells. By contrast, treatment with JYGCT extract significantly reduced the production of TARC, MDC, RANTES, and IL-8, but caused no cytotoxicity, compared with TNF-α and IFN-γ-treated control cells. Consistently, JYGCT extract downregulated the mRNA expression of TARC, MDC, RANTES, and IL-8 induced by TNF-α and IFN-γ in a dose-dependent manner. In addition, TNF-α and IFN-γ markedly increased the phosphorylation of signal transducer and activator of transcription 1 (STAT1) and the nuclear translocation of nuclear factor kappa B (NF-κB) in HaCaT cells. By contrast, TNF-α and IFN-γ-induced activation of STAT1 and NF-κB activation was inhibited by JYGCT treatment in a dose-dependent manner. Our data indicate that JYGCT attenuates TNF-α and IFN-γ-mediated chemokine production by targeting the STAT1 and NF-κB signalling in keratinocytes. Our findings suggest that JYGCT has potential as a therapeutic drug candidate for the treatment of inflammatory skin diseases. PMID:25765840

  11. Cancer-associated fibroblasts promote hepatocellular carcinoma metastasis through chemokine-activated hedgehog and TGF-β pathways.

    PubMed

    Liu, Jiao; Chen, Sheng; Wang, Wei; Ning, Bei-Fang; Chen, Fei; Shen, Weifeng; Ding, Jin; Chen, Wansheng; Xie, Wei-Fen; Zhang, Xin

    2016-08-28

    Fibroblasts are rich in the surrounding microenvironment of hepatocellular carcinoma (HCC) because most HCCs occur in fibrotic or cirrhotic livers. However, the role of cancer-associated fibroblasts (CAFs) in HCC metastasis remains obscure. Here, we reported that CAFs promote the migration and invasion of HCC cells in vitro and facilitate the HCC metastasis to the bone, brain and lung in NOD/SCID mice. The RayBio human chemokine antibody array revealed that CAFs secret higher levels of CCL2, CCL5, CCL7 and CXCL16 than peri-tumor fibroblasts. CCL2 and CCL5 increase the migration but not the invasion of HCC cells, while CCL7 and CXCL16 promote both migration and invasion of HCC cells. Moreover, CCL2 and CCL5 stimulate the activation of the hedgehog (Hh) pathway, while CCL7 and CXCL16 enhance the activity of the transforming growth factor-β (TGF-β) pathway in HCC cells. The neutralizing antibodies of chemokines notably attenuate the effect of CAFs on HCC metastasis and compromised the activation of Hh and TGF-β pathways in HCC cells. In summary, CAF-secreted CCL2, CCL5, CCL7 and CXCL16 promote HCC metastasis through the coordinate activation of Hh and TGF-β pathways in HCC cells. PMID:27216982

  12. Chemokines in the balance: maintenance of homeostasis and protection at CNS barriers

    PubMed Central

    Williams, Jessica L.; Holman, David W.; Klein, Robyn S.

    2014-01-01

    In the adult central nervous system (CNS), chemokines and their receptors are involved in developmental, physiological and pathological processes. Although most lines of investigation focus on their ability to induce the migration of cells, recent studies indicate that chemokines also promote cellular interactions and activate signaling pathways that maintain CNS homeostatic functions. Many homeostatic chemokines are expressed on the vasculature of the blood brain barrier (BBB) including CXCL12, CCL19, CCL20, and CCL21. While endothelial cell expression of these chemokines is known to regulate the entry of leukocytes into the CNS during immunosurveillance, new data indicate that CXCL12 is also involved in diverse cellular activities including adult neurogenesis and neuronal survival, having an opposing role to the homeostatic chemokine, CXCL14, which appears to regulate synaptic inputs to neural precursors. Neuronal expression of CX3CL1, yet another homeostatic chemokine that promotes neuronal survival and communication with microglia, is partly regulated by CXCL12. Regulation of CXCL12 is unique in that it may regulate its own expression levels via binding to its scavenger receptor CXCR7/ACKR3. In this review, we explore the diverse roles of these and other homeostatic chemokines expressed within the CNS, including the possible implications of their dysfunction as a cause of neurologic disease. PMID:24920943

  13. Inflammatory cytokines regulate secretion of VEGF and chemokines by human conjunctival fibroblasts: Role in dysfunctional tear syndrome.

    PubMed

    Nagineni, Chandrasekharam N; William, Abitha; Cherukuri, Aswini; Samuel, William; Hooks, John J; Detrick, Barbara

    2016-02-01

    Ocular surface inflammation is one of the primary mechanisms associated with dysfunctional tear syndrome (DTS), also known as dry eye disease. DTS, more prevalent in older populations, causes ocular discomfort and visual disturbance due to dryness on the surface layer in the eye. We used human conjunctival fibroblast cultures (HCJVF) to investigate the effects of inflammatory cytokines IFN-γ, TNF-α and IL-1β (ITI) on the secretions of VEGF and chemokines. Our results demonstrate the elevated secretion of angiogenic VEGF molecules by ITI without affecting anti-angiogenic molecules, PEDF, endostatin, thrombospondin and sVEGF-R1. The secretion of interferon-γ inducible chemokines, CXCL9, -10, -11 by HCJVF were significantly enhanced by ITI. Our in vitro study supports previously reported observations of elevated VEGF and chemokines in tear fluids of DTS patients, reiterating the role of inflammatory reactions in DTS. PMID:26615568

  14. Identification of the bacterial protein FtsX as a unique target of chemokine-mediated antimicrobial activity against Bacillus anthracis

    PubMed Central

    Crawford, Matthew A.; Lowe, David E.; Fisher, Debra J.; Stibitz, Scott; Plaut, Roger D.; Beaber, John W.; Zemansky, Jason; Mehrad, Borna; Glomski, Ian J.; Strieter, Robert M.; Hughes, Molly A.

    2011-01-01

    Chemokines are a family of chemotactic cytokines that function in host defense by orchestrating cellular movement during infection. In addition to this function, many chemokines have also been found to mediate the direct killing of a range of pathogenic microorganisms through an as-yet-undefined mechanism. As an understanding of the molecular mechanism and microbial targets of chemokine-mediated antimicrobial activity is likely to lead to the identification of unique, broad-spectrum therapeutic targets for effectively treating infection, we sought to investigate the mechanism by which the chemokine CXCL10 mediates bactericidal activity against the Gram-positive bacterium Bacillus anthracis, the causative agent of anthrax. Here, we report that disruption of the gene ftsX, which encodes the transmembrane domain of a putative ATP-binding cassette transporter, affords resistance to CXCL10-mediated antimicrobial effects against vegetative B. anthracis bacilli. Furthermore, we demonstrate that in the absence of FtsX, CXCL10 is unable to localize to its presumed site of action at the bacterial cell membrane, suggesting that chemokines interact with specific, identifiable bacterial components to mediate direct microbial killing. These findings provide unique insight into the mechanism of CXCL10-mediated bactericidal activity and establish, to our knowledge, the first description of a bacterial component critically involved in the ability of host chemokines to target and kill a bacterial pathogen. These observations also support the notion of chemokine-mediated antimicrobial activity as an important foundation for the development of innovative therapeutic strategies for treating infections caused by pathogenic, potentially multidrug-resistant microorganisms. PMID:21949405

  15. Identification of the bacterial protein FtsX as a unique target of chemokine-mediated antimicrobial activity against Bacillus anthracis.

    PubMed

    Crawford, Matthew A; Lowe, David E; Fisher, Debra J; Stibitz, Scott; Plaut, Roger D; Beaber, John W; Zemansky, Jason; Mehrad, Borna; Glomski, Ian J; Strieter, Robert M; Hughes, Molly A

    2011-10-11

    Chemokines are a family of chemotactic cytokines that function in host defense by orchestrating cellular movement during infection. In addition to this function, many chemokines have also been found to mediate the direct killing of a range of pathogenic microorganisms through an as-yet-undefined mechanism. As an understanding of the molecular mechanism and microbial targets of chemokine-mediated antimicrobial activity is likely to lead to the identification of unique, broad-spectrum therapeutic targets for effectively treating infection, we sought to investigate the mechanism by which the chemokine CXCL10 mediates bactericidal activity against the Gram-positive bacterium Bacillus anthracis, the causative agent of anthrax. Here, we report that disruption of the gene ftsX, which encodes the transmembrane domain of a putative ATP-binding cassette transporter, affords resistance to CXCL10-mediated antimicrobial effects against vegetative B. anthracis bacilli. Furthermore, we demonstrate that in the absence of FtsX, CXCL10 is unable to localize to its presumed site of action at the bacterial cell membrane, suggesting that chemokines interact with specific, identifiable bacterial components to mediate direct microbial killing. These findings provide unique insight into the mechanism of CXCL10-mediated bactericidal activity and establish, to our knowledge, the first description of a bacterial component critically involved in the ability of host chemokines to target and kill a bacterial pathogen. These observations also support the notion of chemokine-mediated antimicrobial activity as an important foundation for the development of innovative therapeutic strategies for treating infections caused by pathogenic, potentially multidrug-resistant microorganisms.

  16. Association of elevated transcript levels of interferon-inducible chemokines with disease activity and organ damage in systemic lupus erythematosus patients

    PubMed Central

    Fu, Qiong; Chen, Xiaoqing; Cui, Huijuan; Guo, Yanzhi; Chen, Jing; Shen, Nan; Bao, Chunde

    2008-01-01

    Introduction Systemic lupus erythematosus (SLE) is a multi-system autoimmune disease with a heterogeneous course and varying degrees of severity and organ damage; thus, there is increasing interest in identifying biomarkers for SLE. In this study we correlated the combined expression level of multiple interferon-inducible chemokines with disease activity, degree of organ damage and clinical features in SLE, and we investigated their roles as biomarkers. Methods Peripheral blood cells obtained from 67 patients with SLE patients, 20 patients with rheumatoid arthritis (RA) and 23 healthy donors were subjected to real-time PCR in order to measure the transcriptional levels of seven interferon-inducible chemokines (RANTES, MCP-1, CCL19, MIG, IP-10, CXCL11, and IL-8). The data were used to calculate a chemokine score for each participant, after which comparisons were performed between various groups of SLE patients and control individuals. Results Chemokine scores were significantly elevated in SLE patients versus RA patients and healthy donors (P = 0.012 and P = 0.002, respectively). Chemokine scores were correlated positively with SLE Disease Activity Index 2000 scores (P = 0.005) and negatively with C3 levels (P < 0.001). Compared with patients without lupus nephritis and those with inactive lupus nephritis, chemokine scores were elevated in patients with active lupus nephritis, especially when their daily prednisone dosage was under 30 mg (P = 0.002 and P = 0.014, respectively). Elevated chemokine scores were also associated with the presence of cumulative organ damage (Systemic Lupus International Collaborating Clinics/American Society of Rheumatology Damage Index ≥ 1; P = 0.010) and the occurrence of anti-Sm or anti-RNP autoantibodies (both P = 0.021). Conclusions The combined transcription level of interferon-inducible chemokines in peripheral blood leucocytes is closely associated with disease activity, degree of organ damage, and specific autoantibody patterns

  17. Inhibitor of apoptosis proteins (IAPs) and their antagonists regulate spontaneous and tumor necrosis factor (TNF)-induced proinflammatory cytokine and chemokine production.

    PubMed

    Kearney, Conor J; Sheridan, Clare; Cullen, Sean P; Tynan, Graham A; Logue, Susan E; Afonina, Inna S; Vucic, Domagoj; Lavelle, Ed C; Martin, Seamus J

    2013-02-15

    Inhibitor of apoptosis proteins (IAPs) play a major role in determining whether cells undergo apoptosis in response to TNF as well as other stimuli. However, TNF is also highly proinflammatory through its ability to trigger the secretion of multiple inflammatory cytokines and chemokines, which is arguably the most important role of TNF in vivo. Indeed, deregulated production of TNF-induced cytokines is a major driver of inflammation in several autoimmune conditions such as rheumatoid arthritis. Here, we show that IAPs are required for the production of multiple TNF-induced proinflammatory mediators. Ablation or antagonism of IAPs potently suppressed TNF- or RIPK1-induced proinflammatory cytokine and chemokine production. Surprisingly, IAP antagonism also led to spontaneous production of chemokines, particularly RANTES, in vitro and in vivo. Thus, IAPs play a major role in influencing the production of multiple inflammatory mediators, arguing that these proteins are important regulators of inflammation in addition to apoptosis. Furthermore, small molecule IAP antagonists can modulate spontaneous as well as TNF-induced inflammatory responses, which may have implications for use of these agents in therapeutic settings.

  18. Acidic pH stimulates the production of the angiogenic CXC chemokine, CXCL8 (interleukin-8), in human adult mesenchymal stem cells via the extracellular signal-regulated kinase, p38 mitogen-activated protein kinase, and NF-kappaB pathways.

    PubMed

    Bischoff, David S; Zhu, Jian-Hua; Makhijani, Nalini S; Yamaguchi, Dean T

    2008-07-01

    Blood vessel injury results in limited oxygen tension and diffusion leading to hypoxia, increased anaerobic metabolism, and elevated production of acidic metabolites that cannot be easily removed due to the reduced blood flow. Therefore, an acidic extracellular pH occurs in the local microenvironment of disrupted bone. The potential role of acidic pH and glu-leu-arg (ELR(+)) CXC chemokines in early events in bone repair was studied in human mesenchymal stem cells (hMSCs) treated with medium of decreasing pH (7.4, 7.0, 6.7, and 6.4). The cells showed a reciprocal increase in CXCL8 (interleukin-8, IL-8) mRNA levels as extracellular pH decreased. At pH 6.4, CXCL8 mRNA was induced >60x in comparison to levels at pH 7.4. hMSCs treated with osteogenic medium (OGM) also showed an increase in CXCL8 mRNA with decreasing pH; although, at a lower level than that seen in cells grown in non-OGM. CXCL8 protein was secreted into the medium at all pHs with maximal induction at pH 6.7. Inhibition of the G-protein-coupled receptor alpha, G(alphai), suppressed CXCL8 levels in response to acidic pH; whereas phospholipase C inhibition had no effect on CXCL8. The use of specific mitogen-activated protein kinase (MAPK) signal transduction inhibitors indicated that the pH-dependent increase in CXCL8 mRNA is due to activation of ERK and p38 pathways. The JNK pathway was not involved. NF-kappaB inhibition resulted in a decrease in CXCL8 levels in hMSCs grown in non-OGM. However, OGM-differentiated hMSCs showed an increase in CXCL8 levels when treated with the NF-kappaB inhibitor PDTC, a pyrrolidine derivative of dithiocarbamate.

  19. Evaluation of the Microbicidal Activity and Cytokines/Chemokines Profile Released by Neutrophils from HTLV-1-Infected Individuals

    PubMed Central

    Bezerra, Caroline A.; Cardoso, Thiago M.; Giudice, Angela; Porto, Aurélia F.; Santos, Silvane B.; Carvalho, Edgar M.; Bacellar, Olívia

    2011-01-01

    Human T cell lymphotropic virus type-1 (HTLV-1) induces activation and spontaneous proliferation of T cells with production of type-1 pro-inflammatory cytokines. It modifies the immune response to other antigens and increases susceptibility to infectious diseases. However, little is known about innate immunity in HTLV-1 infection. HTLV-1-infected individuals have higher spontaneous neutrophil activation than HTLV-1-seronegative individuals, as shown by the nitroblue tetrazolium (NBT) assay. This study was conducted to evaluate neutrophil function in HTLV-1-infected individuals. Participants in the study included 18 HTLV-1-infected individuals and 14 HTLV-1-seronegative controls. We evaluated the ability of neutrophils (PMNs) to control a parasite infection, to produce peroxynitrite, cytokines and chemokines and to express activation markers in cultures when stimulated with LPS or infected with Leishmania. When compared with the control group, there was no difference in the percentage of PMNs infected with Leishmania or in the number of amastigotes/100 PMNs in HTLV-1-infected individuals. The microbicidal activity of the PMNs and the levels of CXCL8 and CCL4 released by these cells did not show a difference between HTLV-1-infected individuals and the control group. In both the HTLV-1 group and the control group, infection with Leishmania or stimulation of PMNs led to cellular activation. These observations suggest that neutrophils from HTLV-1-infected individuals have preserved their ability to become activated and to produce chemokines and peroxynitrite after stimulation and that the susceptibility to infection by intracellular Leishmania amazonensis in HTLV-1-infected individuals does not depend on impairment of neutrophil function. PMID:21595736

  20. Neuropeptide substance P upregulates chemokine and chemokine receptor expression in primary mouse neutrophils.

    PubMed

    Sun, Jia; Ramnath, Raina Devi; Bhatia, Madhav

    2007-08-01

    Neuropeptides play an important role in the active communication between the nervous and immune systems. Substance P (SP) is a prominent neuropeptide involved in neurogenic inflammation and has been reported to exert various proinflammatory actions on inflammatory leukocytes including neutrophils. The present study further investigated the modulatory effect of SP (1 muM) on chemokine production and chemokine receptor expression in primary mouse neutrophils. Our results showed that SP primed neutrophils for chemotactic responses not only to the CXC chemokine macrophage inflammatory protein (MIP)-2/CXCL2 but also to the CC chemokine MIP-1alpha/CCL3. The activating effect of SP on neutrophils was further evidenced by upregulation of the CD11b integrin, the activation marker of neutrophils. SP induced both the mRNA and protein expression of the chemokines MIP-1alpha/CCL3 and MIP-2/CXCL2 in neutrophils and upregulated the chemokine receptors CC chemokine receptor (CCR)-1 and CXC chemokine receptor (CXCR)-2. This stimulatory effect on chemokine and chemokine receptor expression in neutrophils was further found to be neurokinin-1 receptor (NK-1R) specific. Pretreatment with selective NK-1R antagonists inhibited SP-triggered activation of neutrophils and chemokine and chemokine receptor upregulation. Moreover, SP-induced chemokine upregulation was NF-kappaB dependent. SP time dependently induced NF-kappaB p65 binding activity, IkappaBalpha degradation, and NF-kappaB p65 nuclear translocation in neutrophils. Inhibition of NF-kappaB activation with its inhibitor Bay11-7082 (10 muM) abolished SP-induced NF-kappaB binding activity and upregulation of MIP-1alpha/CCL3 and MIP-2/CXCL2 in neutrophils. Together, these results suggest that SP exerts a direct stimulatory effect on the expression of chemokines and chemokine receptors in mouse neutrophils. The effect is NK-1R mediated, involving NF-kappaB activation.

  1. Biased signaling at chemokine receptors.

    PubMed

    Corbisier, Jenny; Galès, Céline; Huszagh, Alexandre; Parmentier, Marc; Springael, Jean-Yves

    2015-04-10

    The ability of G protein-coupled receptors (GPCRs) to activate selective signaling pathways according to the conformation stabilized by bound ligands (signaling bias) is a challenging concept in the GPCR field. Signaling bias has been documented for several GPCRs, including chemokine receptors. However, most of these studies examined the global signaling bias between G protein- and arrestin-dependent pathways, leaving unaddressed the potential bias between particular G protein subtypes. Here, we investigated the coupling selectivity of chemokine receptors CCR2, CCR5, and CCR7 in response to various ligands with G protein subtypes by using bioluminescence resonance energy transfer biosensors monitoring directly the activation of G proteins. We also compared data obtained with the G protein biosensors with those obtained with other functional readouts, such as β-arrestin-2 recruitment, cAMP accumulation, and calcium mobilization assays. We showed that the binding of chemokines to CCR2, CCR5, and CCR7 activated the three Gαi subtypes (Gαi1, Gαi2, and Gαi3) and the two Gαo isoforms (Gαoa and Gαob) with potencies that generally correlate to their binding affinities. In addition, we showed that the binding of chemokines to CCR5 and CCR2 also activated Gα12, but not Gα13. For each receptor, we showed that the relative potency of various agonist chemokines was not identical in all assays, supporting the notion that signaling bias exists at chemokine receptors.

  2. The exodus subfamily of CC chemokines inhibits the proliferation of chronic myelogenous leukemia progenitors.

    PubMed

    Hromas, R; Cripe, L; Hangoc, G; Cooper, S; Broxmeyer, H E

    2000-02-15

    Chemokines are a family of related proteins that regulate leukocyte infiltration into inflamed tissue and play important roles in disease processes. Among the biologic activities of chemokines is inhibition of proliferation of normal hematopoietic progenitors. However, chemokines that inhibit normal progenitors rarely inhibit proliferation of hematopoietic progenitors from patients with chronic myelogenous leukemia (CML). We and others recently cloned a subfamily of CC chemokines that share similar amino-terminal peptide sequences and a remarkable ability to chemoattract T cells. These chemokines, Exodus-1/LARC/MIP-3alpha, Exodus-2/SLC/6Ckine/TCA4, and Exodus-3/CKbeta11/MIP-3beta, were found to inhibit proliferation of normal human marrow progenitors. The study described here found that these chemokines also inhibited the proliferation of progenitors in every sample of marrow from patients with CML that was tested. This demonstration of consistent inhibition of CML progenitor proliferation makes the 3 Exodus chemokines unique among chemokines. (Blood. 2000;95:1506-1508)

  3. Transcription factor RUNX2 up-regulates chemokine receptor CXCR4 to promote invasive and metastatic potentials of human gastric cancer

    PubMed Central

    Guo, Zheng-Jun; Yang, Lang; Qian, Feng; Wang, Yan-Xia; Yu, Xi; Ji, Cheng-Dong; Cui, Wei; Xiang, Dong-Fang; Zhang, Xia; Zhang, Peng; Wang, Ji Ming; Cui, You-Hong; Bian, Xiu-Wu

    2016-01-01

    Runt-related transcription factor 2 (RUNX2) is a regulator of embryogenesis and development, but has also been implicated in the progression of certain human cancer. This study aimed to elucidate the role of RUNX2 in the invasive and metastatic potentials of human gastric cancer (GC) and the underlying mechanisms. We found that the levels of RUNX2 expression in gastric cancer tissues were correlated with the differentiation degrees, invasion depth and lymph node metastasis. COX regression analysis indicated that RUNX2 was an independent prognostic indicator for GC patients. RUNX2 significantly increased the migration and invasion ability of GC cells in vitro and enhanced the invasion and metastatic potential of GC cells in an orthotopic GC model of nude mice. Mechanistically, RUNX2 directly bound to the promoter region of the gene coding for the chemokine receptor CXCR4 to enhance its transcription. CXCR4 knockdown or treatment with AMD3100, a CXCR4 inhibitor, attenuated RUNX2-promoted invasion and metastasis. These results demonstrate that RUNX2 promotes the invasion and metastasis of human GC by transcriptionally up-regulating the chemokine receptor CXCR4. Therefore, the RUNX2-CXCR4 axis is a potential therapeutic target for GC. PMID:27007162

  4. AAV-IL-22 modifies liver chemokine activity and ameliorates portal inflammation in murine autoimmune cholangitis.

    PubMed

    Hsueh, Yu-Hsin; Chang, Yun-Ning; Loh, Chia-En; Gershwin, M Eric; Chuang, Ya-Hui

    2016-01-01

    There remain significant obstacles in developing biologics to treat primary biliary cholangitis (PBC). Although a number of agents have been studied both in murine models and human patients, the results have been relatively disappointing. IL-22 is a member of the IL-10 family and has multiple theoretical reasons for predicting successful usage in PBC. We have taken advantage of an IL-22 expressing adeno-associated virus (AAV-IL-22) to address the potential role of IL-22 in not only protecting mice from autoimmune cholangitis, but also in treating animals with established portal inflammation. Using our established mouse model of 2-OA-OVA immunization, including α-galactosylceramide (α-GalCer) stimulation, we treated mice both before and after the onset of clinical disease with AAV-IL-22. Firstly, AAV-IL-22 treatment given prior to 2-OA-OVA and α-GalCer exposure, i.e. before the onset of disease, significantly reduces the portal inflammatory response, production of Th1 cytokines and appearance of liver fibrosis. It also reduced the liver lymphotropic chemokines CCL5, CCL19, CXCL9, and CXCL10. Secondly, and more importantly, therapeutic use of AAV-IL-22, administered after the onset of disease, achieved a greater hurdle and significantly improved portal pathology. Further the improvements in inflammation were negatively correlated with levels of CCL5 and CXCL10 and positively correlated with levels of IL-22. In conclusion, we submit that the clinical use of IL-22 has a potential role in modulating the inflammatory portal process in patients with PBC.

  5. Peroxisome proliferator-activated receptor {alpha} agonists modulate Th1 and Th2 chemokine secretion in normal thyrocytes and Graves' disease

    SciTech Connect

    Antonelli, Alessandro; Ferrari, Silvia Martina; Frascerra, Silvia; Corrado, Alda; Pupilli, Cinzia; Bernini, Giampaolo; Benvenga, Salvatore; Ferrannini, Ele; Fallahi, Poupak

    2011-07-01

    Until now, no data are present about the effect of peroxisome proliferator-activated receptor (PPAR){alpha} activation on the prototype Th1 [chemokine (C-X-C motif) ligand (CXCL)10] (CXCL10) and Th2 [chemokine (C-C motif) ligand 2] (CCL2) chemokines secretion in thyroid cells. The role of PPAR{alpha} and PPAR{gamma} activation on CXCL10 and CCL2 secretion was tested in Graves' disease (GD) and control primary thyrocytes stimulated with interferon (IFN){gamma} and tumor necrosis factor (TNF){alpha}. IFN{gamma} stimulated both CXCL10 and CCL2 secretion in primary GD and control thyrocytes. TNF{alpha} alone stimulated CCL2 secretion, while had no effect on CXCL10. The combination of IFN{gamma} and TNF{alpha} had a synergistic effect both on CXCL10 and CCL2 chemokines in GD thyrocytes at levels comparable to those of controls. PPAR{alpha} activators inhibited the secretion of both chemokines (stimulated with IFN{gamma} and TNF{alpha}) at a level higher (for CXCL10, about 60-72%) than PPAR{gamma} agonists (about 25-35%), which were confirmed to inhibit CXCL10, but not CCL2. Our data show that CCL2 is modulated by IFN{gamma} and TNF{alpha} in GD and normal thyrocytes. Furthermore we first show that PPAR{alpha} activators inhibit the secretion of CXCL10 and CCL2 in thyrocytes, suggesting that PPAR{alpha} may be involved in the modulation of the immune response in the thyroid.

  6. Utility of CSF Cytokine/Chemokines as Markers of Active Intrathecal Inflammation: Comparison of Demyelinating, Anti-NMDAR and Enteroviral Encephalitis

    PubMed Central

    Kothur, Kavitha; Wienholt, Louise; Mohammad, Shekeeb S.; Tantsis, Esther M.; Pillai, Sekhar; Britton, Philip N.; Jones, Cheryl A.; Angiti, Rajeshwar R.; Barnes, Elizabeth H.; Schlub, Timothy; Bandodkar, Sushil; Brilot, Fabienne; Dale, Russell C.

    2016-01-01

    Background Despite the discovery of CSF and serum diagnostic autoantibodies in autoimmune encephalitis, there are still very limited CSF biomarkers for diagnostic and monitoring purposes in children with inflammatory or autoimmune brain disease. The cause of encephalitis is unknown in up to a third of encephalitis cohorts, and it is important to differentiate infective from autoimmune encephalitis given the therapeutic implications. Aim To study CSF cytokines and chemokines as diagnostic biomarkers of active neuroinflammation, and assess their role in differentiating demyelinating, autoimmune, and viral encephalitis. Methods We measured and compared 32 cytokine/chemokines using multiplex immunoassay and APRIL and BAFF using ELISA in CSF collected prior to commencing treatment from paediatric patients with confirmed acute disseminated encephalomyelitis (ADEM, n = 16), anti-NMDAR encephalitis (anti-NMDAR E, n = 11), and enteroviral encephalitis (EVE, n = 16). We generated normative data using CSF from 20 non-inflammatory neurological controls. The sensitivity of CSF cytokine/chemokines to diagnose encephalitis cases was calculated using 95th centile of control values as cut off. We correlated CSF cytokine/chemokines with disease severity and follow up outcome based on modified Rankin scale. One-way hierarchical correlational cluster analysis of molecules was performed in different encephalitis and outcome groups. Results In descending order, CSF TNF-α, IL-10, IFN-α, IL-6, CXCL13 and CXCL10 had the best sensitivity (>79.1%) when all encephalitis patients were included. The combination of IL-6 and IFN-α was most predictive of inflammation on multiple logistic regression with area under the ROC curve 0.99 (CI 0.97–1.00). There were no differences in CSF cytokine concentrations between EVE and anti-NMDAR E, whereas ADEM showed more pronounced elevation of Th17 related (IL-17, IL-21) and Th2 (IL-4, CCL17) related cytokine/chemokines. Unlike EVE, heat map analysis

  7. ROLE OF CHEMOKINES IN TUMOR GROWTH

    PubMed Central

    Raman, Dayanidhi; Baugher, Paige J.; Thu, Yee Mon; Richmond, Ann

    2007-01-01

    Chemokines play a paramount role in the tumor progression. Chronic inflammation promotes tumor formation. Both tumor cells and stromal cells elaborate chemokines and cytokines. These act either by autocrine or paracrine mechanisms to sustain tumor cell growth, induce angiogenesis and facilitate evasion of immune surveillance through immunoediting. The chemokine receptor CXCR2 and its ligands promote tumor angiogenesis and leukocyte infiltration into the tumor microenvironment. In harsh acidic and hypoxic microenvironmental conditions tumor cells up-regulate their expression of CXCR4, which equips them to migrate up a gradient of CXCL12 elaborated by carcinoma associated fibroblasts (CAFs) to a normoxic microenvironment. The CXCL12-CXCR4 axis facilitates metastasis to distant organs and the CCL21-CCR7 chemokine ligand-receptor pair favors metastasis to lymph nodes. These two chemokine ligand-receptor systems are common key mediators of tumor cell metastasis for several malignancies and as such provide key targets for chemotherapy. In this paper, the role of specific chemokines/chemokine receptor interactions in tumor progression, growth and metastasis and the role of chemokine/chemokine receptor interactions in the stromal compartment as related to angiogenesis, metastasis, and immune response to the tumor are reviewed. PMID:17629396

  8. Entamoeba lysyl-tRNA Synthetase Contains a Cytokine-Like Domain with Chemokine Activity towards Human Endothelial Cells

    PubMed Central

    Han, Jung Min; Kim, Sunghoon; Celada, Antonio; Ribas de Pouplana, Lluís

    2011-01-01

    Immunological pressure encountered by protozoan parasites drives the selection of strategies to modulate or avoid the immune responses of their hosts. Here we show that the parasite Entamoeba histolytica has evolved a chemokine that mimics the sequence, structure, and function of the human cytokine HsEMAPII (Homo sapiens endothelial monocyte activating polypeptide II). This Entamoeba EMAPII-like polypeptide (EELP) is translated as a domain attached to two different aminoacyl-tRNA synthetases (aaRS) that are overexpressed when parasites are exposed to inflammatory signals. EELP is dispensable for the tRNA aminoacylation activity of the enzymes that harbor it, and it is cleaved from them by Entamoeba proteases to generate a standalone cytokine. Isolated EELP acts as a chemoattractant for human cells, but its cell specificity is different from that of HsEMAPII. We show that cell specificity differences between HsEMAPII and EELP can be swapped by site directed mutagenesis of only two residues in the cytokines' signal sequence. Thus, Entamoeba has evolved a functional mimic of an aaRS-associated human cytokine with modified cell specificity. PMID:22140588

  9. Development of operational models of receptor activation including constitutive receptor activity and their use to determine the efficacy of the chemokine CCL17 at the CC chemokine receptor CCR4.

    PubMed

    Slack, R J; Hall, D A

    2012-07-01

    BACKGROUND AND PURPOSE The operational model provides a key conceptual framework for the analysis of pharmacological data. However, this model does not include constitutive receptor activity, a frequent phenomenon in modern pharmacology, particularly in recombinant systems. Here, we developed extensions of the operational model which include constitutive activity and applied them to effects of agonists at the chemokine receptor CCR4. EXPERIMENTAL APPROACH The effects of agonists of CCR4 on [(35) S]GTPγS binding to recombinant cell membranes and on the filamentous (F-) actin content of human CD4(+) CCR4(+) T cells were determined. The basal [(35) S]GTPγS binding was changed by varying the GDP concentration whilst the basal F-actin contents of the higher expressing T cell populations were elevated, suggesting constitutive activity of CCR4. Both sets of data were analysed using the mathematical models. RESULTS The affinity of CCL17 (also known as TARC) derived from analysis of the T cell data (pK(a) = 9.61 ± 0.17) was consistent with radioligand binding experiments (9.50 ± 0.11) while that from the [(35) S]GTPγS binding experiments was lower (8.27 ± 0.09). Its intrinsic efficacy differed between the two systems (110 in T cells vs. 11). CONCLUSIONS AND IMPLICATIONS The presence of constitutive receptor activity allows the absolute intrinsic efficacy of agonists to be determined without a contribution from the signal transduction system. Intrinsic efficacy estimated in this way is consistent with Furchgott's definition of this property. CCL17 may have a higher intrinsic efficacy at CCR4 in human T cells than that expressed recombinantly in CHO cells.

  10. Isolation and characterization of Exodus-2, a novel C-C chemokine with a unique 37-amino acid carboxyl-terminal extension.

    PubMed

    Hromas, R; Kim, C H; Klemsz, M; Krathwohl, M; Fife, K; Cooper, S; Schnizlein-Bick, C; Broxmeyer, H E

    1997-09-15

    Chemokines are a group of small, homologous proteins that regulate leukocyte migration, hemopoiesis, and HIV-1 absorption. We report here the cloning and characterization of a novel murine and human C-C chemokine termed Exodus-2 for its similarity to Exodus-1/MIP-3alpha/LARC, and its chemotactic ability. This novel chemokine has a unique 36 or 37 (murine and human, respectively) amino acid carboxyl-terminal extension not seen in any other chemokine family member. Purified recombinant Exodus-2 was found to have two activities classically associated with chemokines: inhibiting hemopoiesis and stimulating chemotaxis. However, Exodus-2 also had unusual characteristics for C-C chemokines. It selectively stimulated the chemotaxis of T-lymphocytes and was preferentially expressed in lymph node tissue. The combination of these characteristics may be a functional correlate for the unique carboxyl-terminal structure of Exodus-2.

  11. Splicing Regulation of Pro-Inflammatory Cytokines and Chemokines: At the Interface of the Neuroendocrine and Immune Systems.

    PubMed

    Shakola, Felitsiya; Suri, Parul; Ruggiu, Matteo

    2015-01-01

    Alternative splicing plays a key role in posttranscriptional regulation of gene expression, allowing a single gene to encode multiple protein isoforms. As such, alternative splicing amplifies the coding capacity of the genome enormously, generates protein diversity, and alters protein function. More than 90% of human genes undergo alternative splicing, and alternative splicing is especially prevalent in the nervous and immune systems, tissues where cells need to react swiftly and adapt to changes in the environment through carefully regulated mechanisms of cell differentiation, migration, targeting, and activation. Given its prevalence and complexity, this highly regulated mode of gene expression is prone to be affected by disease. In the following review, we look at how alternative splicing of signaling molecules—cytokines and their receptors—changes in different pathological conditions, from chronic inflammation to neurologic disorders, providing means of functional interaction between the immune and neuroendocrine systems. Switches in alternative splicing patterns can be very dynamic and can produce signaling molecules with distinct or antagonistic functions and localization to different subcellular compartments. This newly discovered link expands our understanding of the biology of immune and neuroendocrine cells, and has the potential to open new windows of opportunity for treatment of neurodegenerative disorders. PMID:26371053

  12. Splicing Regulation of Pro-Inflammatory Cytokines and Chemokines: At the Interface of the Neuroendocrine and Immune Systems.

    PubMed

    Shakola, Felitsiya; Suri, Parul; Ruggiu, Matteo

    2015-01-01

    Alternative splicing plays a key role in posttranscriptional regulation of gene expression, allowing a single gene to encode multiple protein isoforms. As such, alternative splicing amplifies the coding capacity of the genome enormously, generates protein diversity, and alters protein function. More than 90% of human genes undergo alternative splicing, and alternative splicing is especially prevalent in the nervous and immune systems, tissues where cells need to react swiftly and adapt to changes in the environment through carefully regulated mechanisms of cell differentiation, migration, targeting, and activation. Given its prevalence and complexity, this highly regulated mode of gene expression is prone to be affected by disease. In the following review, we look at how alternative splicing of signaling molecules—cytokines and their receptors—changes in different pathological conditions, from chronic inflammation to neurologic disorders, providing means of functional interaction between the immune and neuroendocrine systems. Switches in alternative splicing patterns can be very dynamic and can produce signaling molecules with distinct or antagonistic functions and localization to different subcellular compartments. This newly discovered link expands our understanding of the biology of immune and neuroendocrine cells, and has the potential to open new windows of opportunity for treatment of neurodegenerative disorders.

  13. Splicing Regulation of Pro-Inflammatory Cytokines and Chemokines: At the Interface of the Neuroendocrine and Immune Systems

    PubMed Central

    Shakola, Felitsiya; Suri, Parul; Ruggiu, Matteo

    2015-01-01

    Alternative splicing plays a key role in posttranscriptional regulation of gene expression, allowing a single gene to encode multiple protein isoforms. As such, alternative splicing amplifies the coding capacity of the genome enormously, generates protein diversity, and alters protein function. More than 90% of human genes undergo alternative splicing, and alternative splicing is especially prevalent in the nervous and immune systems, tissues where cells need to react swiftly and adapt to changes in the environment through carefully regulated mechanisms of cell differentiation, migration, targeting, and activation. Given its prevalence and complexity, this highly regulated mode of gene expression is prone to be affected by disease. In the following review, we look at how alternative splicing of signaling molecules—cytokines and their receptors—changes in different pathological conditions, from chronic inflammation to neurologic disorders, providing means of functional interaction between the immune and neuroendocrine systems. Switches in alternative splicing patterns can be very dynamic and can produce signaling molecules with distinct or antagonistic functions and localization to different subcellular compartments. This newly discovered link expands our understanding of the biology of immune and neuroendocrine cells, and has the potential to open new windows of opportunity for treatment of neurodegenerative disorders. PMID:26371053

  14. Chemokines and immunity

    PubMed Central

    Palomino, Diana Carolina Torres; Marti, Luciana Cavalheiro

    2015-01-01

    Chemokines are a large family of small cytokines and generally have low molecular weight ranging from 7 to 15kDa. Chemokines and their receptors are able to control the migration and residence of all immune cells. Some chemokines are considered pro-inflammatory, and their release can be induced during an immune response at a site of infection, while others are considered homeostatic and are involved in controlling of cells migration during tissue development or maintenance. The physiologic importance of this family of mediators is resulting from their specificity − members of the chemokine family induce recruitment of well-defined leukocyte subsets. There are two major chemokine sub-families based upon cysteine residues position: CXC and CC. As a general rule, members of the CXC chemokines are chemotactic for neutrophils, and CC chemokines are chemotactic for monocytes and sub-set of lymphocytes, although there are some exceptions. This review discusses the potential role of chemokines in inflammation focusing on the two best-characterized chemokines: monocyte chemoattractant protein-1, a CC chemokine, and interleukin-8, a member of the CXC chemokine sub-family. PMID:26466066

  15. Up-regulation of Interferon-inducible protein 16 contributes to psoriasis by modulating chemokine production in keratinocytes

    PubMed Central

    Cao, Tianyu; Shao, Shuai; Li, Bing; Jin, Liang; Lei, Jie; Qiao, Hongjiang; Wang, Gang

    2016-01-01

    Psoriasis is a common chronic inflammatory skin disease characterized by epidermal hyperplasia and dermal inflammation. Keratinocyte activation is known to play a critical role in psoriasis, but the underlying mechanism remains unclear. Interferon-inducible protein 16 (IFI16), an innate immune system sensor, is reported to affect keratinocyte function. We therefore hypothesized that IFI16 promotes psoriasis by modulating keratinocyte activation. In the present study, we cinfirmed that IFI16 was overexpressed in epidermal keratinocytes of psoriasis patients. In addition, psoriasis-related cytokines, including IFN-γ, TNF-α, IL-17 and IL-22, induced IFI16 up-regulation in keratinocytes via activation of STAT3 signaling. We also observed that IFI16 activated the TBK1-NF-κB signaling, leading to the production of CXCL10 and CCL20. Importantly, knocking down p204, which is reported as the mouse orthologous of human IFI16, inhibited epidermal hyperplasia in mice with imiquimod-induced psoriasiform dermatitis. These findings indicate that IFI16 plays a critical role in the pathogenesis of psoriasis and may be a potential therapeutic target. PMID:27137868

  16. Expression of chemokine receptors in vernal keratoconjunctivitis

    PubMed Central

    El-Asrar, A.; Struyf, S.; Al-Mosallam, A.; Missotten, L.; Van Damme, J.; Geboes, K.

    2001-01-01

    BACKGROUND/AIMS—Chemokines are small peptides which are potent activators and chemoattractants for leucocyte subpopulations. Their action is mediated by a family of seven transmembrane spanning G-protein coupled receptors. The aims of this study were to examine the expression of the chemokine receptors CCR1, CCR3, CCR5, CXCR3, and CXCR4 in the conjunctiva of patients with vernal keratoconjunctivitis (VKC) and to investigate the phenotype of inflammatory cells expressing these chemokine receptors.
METHODS—Conjunctival biopsy specimens from 16 patients with active VKC, and eight control subjects were studied by immunohistochemical techniques using a panel of monoclonal antibodies directed against human CCR1, CCR3, CCR5, CXCR3, and CXCR4. The phenotype of inflammatory cells expressing chemokine receptors was examined by double immunohistochemistry.
RESULTS—In the normal conjunctiva, few inflammatory cells expressed CXCR3 in five of eight specimens. There was no immunoreactivity for CCR1, CCR3, CCR5, and CXCR4. In VKC specimens, membranous immunoreactivity for CXCR3 was noted on inflammatory cells in all specimens. Compared with control specimens, VKC specimens showed significantly more inflammatory cells expressing CXCR3 (54.3 (SD 34.3) v 3.3 (5.0); p<0.001). Few CCR1+, CCR3+, CCR5+, and CXCR4+ inflammatory cells were observed in only three of 16 specimens. Double immunohistochemistry revealed that all CXCR3 positive inflammatory cells were CD3 positive T lymphocytes and that 61.7% (3.7%) of the infiltrating T lymphocytes were reactive for CXCR3.
CONCLUSIONS—CXCR3 is the predominant chemokine receptor and is expressed abundantly on T lymphocytes in the conjunctiva of patients with active VKC. These data suggest a potential role for CXCR3 receptors in the regulation of lymphocyte recruitment within conjunctiva of VKC patients. New therapeutic strategies that block CXCR3 may inhibit T lymphocyte recruitment and suppress adverse inflammatory reactions

  17. Fas signal links innate and adaptive immunity by promoting dendritic-cell secretion of CC and CXC chemokines.

    PubMed

    Guo, Zhenhong; Zhang, Minghui; Tang, Hua; Cao, Xuetao

    2005-09-15

    Dendritic cells (DCs) and chemokines are important in linking innate and adaptive immunity. We previously reported that Fas ligation induced interleukin 1beta (IL-1beta)-dependent maturation and IL-1beta-independent survival of DCs, with extracellular signal-regulated kinase (ERK) and nuclear factor-kappaB (NF-kappaB) signaling pathways involved, respectively. We describe here that Fas ligation induced DCs to rapidly produce both CXC and CC chemokines, including macrophage inflammatory protein 2 (MIP-2), MIP-1alpha, MIP-1beta, monocyte chemoattractant protein 1 (MCP-1), RANTES (regulated on activation normal T cell expressed and secreted), and TARC (thymus and activation-regulated chemokine), resulting in enhanced chemoattraction of neutrophils and T cells by Fas-ligated DCs in vivo or by its supernatant in vitro. These chemokines work synergistically in chemoattraction of neutrophils and T cells with MIP-2 more important for neutrophils, MIP-1alpha and TARC more important for T cells. Moreover, Fas-ligated DCs increased endocytosis by neutrophils and activation and proliferation of antigen-specific naive T cells. Fas ligation-induced DC secretion of chemokines involves Ras/Raf/mitogen-activated protein kinase kinase (MEK)/ERK activation and is ERK, but not NF-kappaB, dependent. Activation of caspases, including caspase 1, but not IL-1 autocrine action, is involved in this process. These data indicate that Fas signaling provides a key link between innate response and adaptive immunity by promoting DC chemokine production.

  18. Thromboxane A2 Regulates CXCL1 and CXCL8 Chemokine Expression in the Nasal Mucosa–Derived Fibroblasts of Chronic Rhinosinusitis Patients

    PubMed Central

    Tsai, Yih-Jeng; Hao, Sheng-Po; Chen, Chih-Li; Wu, Wen-Bin

    2016-01-01

    Background Chronic rhinosinusitis without nasal polyps (CRSsNP) is a common chronic disease and the etiology remains unclear. Thromboxane A2 (TXA2) participates in platelet aggregation and tissue inflammation. In this study, the CXCL1/8 chemokine and TXA2-TP receptor expression in the CRSsNP mucosa was investigated. Experimental Approach Immunohistochemistry, chemokine release assay by ELISA, RT-PCR, Real-time PCR, Western blotting, pharmacological and siRNA knockdown analysis were applied in the CRSsNP tissue specimen and cultured nasal mucosa-derived fibroblasts. Results The immunohistochemistry results indicated that CXCL1 and CXCL8 were highly expressed in the CRSsNP mucosa compared with the controls; however, the TP receptors were expressed in both mucosa. Therefore, U46619 and IBOP, a TXA2 analog and TP agonist, were used to explore the role of TP activation in CXCL1/8 expression; both of these induced CXCL1/8 mRNA and protein expression in CRSsNP mucosa-derived fibroblasts. U46619 phosphorylated PI-3K, cyclic AMP (cAMP)/PKA, PKC, and cAMP response element (CREB). Activation of cAMP/PKA, PKC, and CREB was the major pathway for cxcl1/8 gene transcription. Pharmacological and siRNA knockdown analyses revealed that activation of cAMP/PKA and PKCμ/PKD pathways were required for CREB phosphorylation and PKA/C crosstalked with the PI-3K pathway. Conclusion and Implications Our study provides the first evidence for abundant TP receptor and CXCL1/8 expression in human CRSsNP mucosa and for TXA2 stimulation inducing CXCL1/8 expression in nasal fibroblasts primarily through TP receptor, cAMP/PKA, PKCμ/PKD, and CREB-related pathways. PMID:27351369

  19. Intra-articular CD1c-expressing myeloid dendritic cells from rheumatoid arthritis patients express a unique set of T cell-attracting chemokines and spontaneously induce Th1, Th17 and Th2 cell activity

    PubMed Central

    2013-01-01

    Introduction Myeloid dendritic cells (mDCs) are potent T cell-activating antigen-presenting cells that have been suggested to play a crucial role in the regulation of immune responses in many disease states, including rheumatoid arthritis (RA). Despite this, studies that have reported on the capacity of naturally occurring circulating mDCs to regulate T cell activation in RA are still lacking. This study aimed to evaluate the phenotypic and functional properties of naturally occurring CD1c (BDCA-1)+ mDCs from synovial fluid (SF) compared to those from peripheral blood (PB) of RA patients. Methods CD1c+ mDC numbers and expression of costimulatory molecules were assessed by fluorescence-activated cell sorting (FACS) analysis in SF and PB from RA patients. Ex vivo secretion of 45 inflammatory mediators by mDCs from SF and PB of RA patients was determined by multiplex immunoassay. The capacity of mDCs from SF to activate autologous CD4+ T cells was measured. Results CD1c+ mDC numbers were significantly increased in SF versus PB of RA patients (mean 4.7% vs. 0.6%). mDCs from SF showed increased expression of antigen-presenting (human leukocyte antigen (HLA) class II, CD1c) and costimulatory molecules (CD80, CD86 and CD40). Numerous cytokines were equally abundantly produced by mDCs from both PB and SF (including IL-12, IL-23, IL-13, IL-21). SF mDCs secreted higher levels of interferon γ-inducible protein-10 (IP-10), monokine induced by interferon γ (MIG) and, thymus and activation-regulated chemokine (TARC), but lower macrophage-derived chemokine (MDC) levels compared to mDCs from PB. mDCs from SF displayed a strongly increased capacity to induce proliferation of CD4+ T cells associated with a strongly augmented IFNγ, IL-17, and IL-4 production. Conclusions This study suggests that increased numbers of CD1c+ mDCs in SF are involved in the inflammatory cascade intra-articularly by the secretion of specific T cell-attracting chemokines and the activation of

  20. Rainbow trout CK9, a CCL25-like ancient chemokine that attracts and regulates B cells and macrophages, the main antigen presenting cells in fish.

    PubMed

    Aquilino, Carolina; Granja, Aitor G; Castro, Rosario; Wang, Tiehui; Abos, Beatriz; Parra, David; Secombes, Christopher J; Tafalla, Carolina

    2016-04-01

    CK9 is a rainbow trout (Oncorhynchus mykiss) CC chemokine phylogenetically related to mammalian CCL25. Although CK9 is known to be transcriptionally regulated in response to inflammation particularly in mucosal tissues, its functionality has never been revealed. In the current work, we have demonstrated that CK9 is chemoattractant for antigen presenting cells (APCs) expressing major histocompatibility complex class II (MHC II) on the cell surface. Among these APCs, CK9 has a strong chemotactic capacity for both B cells (IgM+ and IgT+) and macrophages. Along with its chemotactic capacities, CK9 modulated the MHC II turnover of B lymphocytes and up-regulated the phagocytic capacity of both IgM+ cells and macrophages. Although CK9 had no lymphoproliferative effects, it increased the survival of IgT+ lymphocytes. Furthermore, we have established that the chemoattractant capacity of CK9 is strongly increased after pre-incubation of leukocytes with a T-independent antigen, whereas B cell receptor (BCR) cross-linking strongly abrogated their capacity to migrate to CK9, indicating that CK9 preferentially attracts B cells at the steady state or under BCR-independent stimulation. These results point to CK9 being a key regulator of B lymphocyte trafficking in rainbow trout, able to modulate innate functions of teleost B lymphocytes and macrophages.

  1. Rainbow trout CK9, a CCL25-like ancient chemokine that attracts and regulates B cells and macrophages, the main antigen presenting cells in fish

    PubMed Central

    Aquilino, Carolina; Granja, Aitor G.; Castro, Rosario; Wang, Tiehui; Abos, Beatriz; Parra, David; Secombes, Christopher J.; Tafalla, Carolina

    2016-01-01

    CK9 is a rainbow trout (Oncorhynchus mykiss) CC chemokine phylogenetically related to mammalian CCL25. Although CK9 is known to be transcriptionally regulated in response to inflammation particularly in mucosal tissues, its functionality has never been revealed. In the current work, we have demonstrated that CK9 is chemoattractant for antigen presenting cells (APCs) expressing major histocompatibility complex class II (MHC II) on the cell surface. Among these APCs, CK9 has a strong chemotactic capacity for both B cells (IgM+ and IgT+) and macrophages. Along with its chemotactic capacities, CK9 modulated the MHC II turnover of B lymphocytes and up-regulated the phagocytic capacity of both IgM+ cells and macrophages. Although CK9 had no lymphoproliferative effects, it increased the survival of IgT+ lymphocytes. Furthermore, we have established that the chemoattractant capacity of CK9 is strongly increased after pre-incubation of leukocytes with a T-independent antigen, whereas B cell receptor (BCR) cross-linking strongly abrogated their capacity to migrate to CK9, indicating that CK9 preferentially attracts B cells at the steady state or under BCR-independent stimulation. These results point to CK9 being a key regulator of B lymphocyte trafficking in rainbow trout, able to modulate innate functions of teleost B lymphocytes and macrophages. PMID:27003360

  2. Regulated expression of platelet factor 4 in human monocytes--role of PARs as a quantitatively important monocyte activation pathway.

    PubMed

    Schaffner, Andreas; Rhyn, Petra; Schoedon, Gabriela; Schaer, Dominik J

    2005-07-01

    Human mononuclear phagocytes have recently been shown to express constitutively and even more so, upon stimulation with bacteria, fungi, lipopolysaccharide (LPS), zymosan, or thrombin platelet basic protein (PBP). This CXC chemokine as well as platelet factor 4 (PF4), which is located genomically at a short distance from the PBP, were previously considered to be specific markers for the megakaryocyte cell lineage. Both chemokines have signaling and antimicrobial activity. In the present studies, transcriptional and expressional regulation of PF4 and related chemokines was studied in human monocytes. As shown by quantitative mRNA analysis, Western blots, radioimmunoprecipitation of cell extracts, and immunofluorescence and quantitatively with enzyme-linked immunosorbent assay, human monocytes express PF4 in the same order of magnitude as the known, regulated CXC chemokine interleukin (IL)-8. Expression of PF4 is up-regulated at the mRNA and protein level by thrombin and mediated by proteinase-activated receptors (PARs), resulting in a 32- to 128-fold higher mRNA level and leading to an up-to-sixfold increase of the peptide concentration in monocyte culture supernatants. Thrombin and the synthetic ligand of PAR-1 and PAR-2, SFLLRN, also induced comparable increases in the levels of mRNA for PBP, IL-8, regulated on activation, normal T expressed and secreted (RANTES), monocyte chemoattractant protein-1, and macrophage-inflammatory protein-1alpha and increased synthesis of these chemokines as shown by immunofluorescence or a quantitative immunobead-based method. The induction of increased mRNA levels for all chemokines by SFLLRN was unsurpassed by LPS, zymosan, interferon-gamma (IFN-gamma), tumor necrosis factor alpha (TNF-alpha), and IL-1. Activation of monocytes through PARs represents an alternate activation mechanism, independent from IFN-gamma, TNF-alpha, or other signaling pathways. PMID:15788441

  3. Structural insights into the interaction between a potent anti-inflammatory protein, viral CC chemokine inhibitor (vCCI), and the human CC chemokine, Eotaxin-1.

    PubMed

    Kuo, Nai-Wei; Gao, Yong-Guang; Schill, Megan S; Isern, Nancy; Dupureur, Cynthia M; Liwang, Patricia J

    2014-03-01

    Chemokines play important roles in the immune system, not only recruiting leukocytes to the site of infection and inflammation but also guiding cell homing and cell development. The soluble poxvirus-encoded protein viral CC chemokine inhibitor (vCCI), a CC chemokine inhibitor, can bind to human CC chemokines tightly to impair the host immune defense. This protein has no known homologs in eukaryotes and may represent a potent method to stop inflammation. Previously, our structure of the vCCI·MIP-1β (macrophage inflammatory protein-1β) complex indicated that vCCI uses negatively charged residues in β-sheet II to interact with positively charged residues in the MIP-1β N terminus, 20s region and 40s loop. However, the interactions between vCCI and other CC chemokines have not yet been fully explored. Here, we used NMR and fluorescence anisotropy to study the interaction between vCCI and eotaxin-1 (CCL11), a CC chemokine that is an important factor in the asthma response. NMR results reveal that the binding pattern is very similar to the vCCI·MIP-1β complex and suggest that electrostatic interactions provide a major contribution to binding. Fluorescence anisotropy results on variants of eotaxin-1 further confirm the critical roles of the charged residues in eotaxin-1. In addition, the binding affinity between vCCI and other wild type CC chemokines, MCP-1 (monocyte chemoattractant protein-1), MIP-1β, and RANTES (regulated on activation normal T cell expressed and secreted), were determined as 1.1, 1.2, and 0.22 nm, respectively. To our knowledge, this is the first work quantitatively measuring the binding affinity between vCCI and multiple CC chemokines.

  4. Constitutive and inflammatory induction of alpha and beta chemokines in human first trimester forebrain astrocytes and neurons.

    PubMed

    Bakhiet, Moiz; Mousa, Alyaa; Seiger, Ake; Andersson, Jan

    2002-05-01

    Chemokine effects on leukocyte infiltration into the central nervous system (CNS) are key events in the inflammatory processes of neuroimmunologic and neuroinfectious diseases. Because, chemokines may play important roles in proliferation and differentiation of brain cells and in the initiation and progression of CNS inflammatory disorders, we analyzed constitutive and inflammatory-induced expression of alpha and beta chemokines in human first trimester forebrain cells. Constitutive induction of IL-8, MIP-1alpha, MIP-1beta, MCP-1 and regulated on activation, normal T-cell expressed, and secreted (Rantes) was detected in cryostat sections of embryonic forebrains in an age-dependent manner. Dissociated cell cultures were studied for spontaneous chemokine induction and after stimulation with the trypanosome lymphocyte triggering factor (TLTF), a novel trypanokine secreted by African trypanosomes that triggers a complex of immune responses. LPS and variant surface glycoprotein (VSG) were used as controls. In cultures, unstimulated cells expressed minimal chemokine levels except for Rantes. In response to TLTF and LPS, but not VSG, all chemokines were highly induced at the mRNA and protein levels in a dose- and age-dependent manner. Combined assays (in situ hybridization and immunohistochemistry) revealed that astrocytes and neurons are major sources for chemokines. These results illustrate the ability of resident brain cells to constitutively express chemokine genes, which may suggest an important role for chemokines during brain development. Furthermore, TLTF-induced chemokine expression in astrocytes and neurons indicate the capacity of TLTF to provoke neuroinflammation in the brain, which may have important therapeutic implications for the neurological manifestations of African trypanosomiasis. PMID:12009570

  5. Pathophysiological roles of chemokines in human reproduction: an overview.

    PubMed

    Kitaya, Kotaro; Yamada, Hisao

    2011-05-01

    Chemokines are a group of small cytokines that have an ability to induce leukocyte migration. Chemokines exert their functions by binding and activating specific G protein-coupled receptors. Studies have unveiled pleiotropic bioactivities of chemokines in various phenomena ranging from immunomodulation, embryogenesis, and homeostasis to pathogenesis. In the mammalian reproductive system, chemokines unexceptionally serve in multimodal events that are closely associated with establishment, maintenance, and deterioration of fecundity. The aim of this review is to update the knowledge on chemokines in male and female genital organs, with a focus on their potential pathophysiological roles in human reproduction.

  6. Chemokine receptors in airway disease: which receptors to target?

    PubMed

    Owen, C

    2001-01-01

    Many disease states within the airway result in the co-ordinated infiltration of key inflammatory cells. The cellular influx is choreographed through the temporal and spatially-regulated expression of chemokines, which potentiate the migration of cells along gradients of chemotactic ligands. Chemokines act as ligands for the chemokine receptors; a distinct class of G-protein-coupled receptor. Over 40 chemokine ligands and 18 chemokine receptors have been identified on human cells. Chemokine receptors are divided into several classes; the two most prominent of which are the CC- and CXC-chemokine receptors, classified through the spatial arrangement of two conserved cysteine residues. The role of chemokine receptors such as CCR2, CCR3, CCR4, CCR8 and the CXC chemokine receptors; CXCR1 and CXCR2 on cell types of relevance to respiratory diseases such as asthma, chronic obstructive pulmonary disease (COPD) and chronic bronchitis will be explored in this review. Chemokines have proven to be amenable drug targets for the development of low molecular weight antagonists by the pharmaceutical industry. So far, no chemokine receptor antagonist has entered the clinic in trials for respiratory disease, but over the next few years it is expected that many will do so, at which time the potential of these exciting new targets will be fully realised.

  7. Identification of a Sustained Neurogenic Zone at the Dorsal Surface of the Adult Mouse Hippocampus and Its Regulation by the Chemokine SDF-1

    PubMed Central

    Belmadani, Abdelhak; Ren, Dongjun; Bhattacharyya, Bula J.; Rothwangl, Katharina B.; Hope, Thomas J.; Perlman, Harris; Miller, Richard J.

    2015-01-01

    We identified a previously unknown neurogenic region at the dorsal surface of the hippocampus; (the “subhippocampal zone,” SHZ) in the adult brain. Using a reporter mouse in which SHZ cells and their progeny could be traced through the expression of EGFP under the control of the CXCR4 chemokine receptor promoter we observed the presence of a pool of EGFP expressing cells migrating in direction of the dentate gyrus (DG), which is maintained throughout adulthood. This population appeared to originate from the SHZ where cells entered a caudal migratory stream (aCMS) that included the fimbria, the meninges and the DG. Deletion of CXCR4 from neural stem cells (NSCs) or neuroinflammation resulted in the appearance of neurons in the DG, which were the result of migration of NSCs from the SHZ. Some of these neurons were ectopically placed. Our observations indicate that the SHZ is a neurogenic zone in the adult brain through migration of NSCs in the aCMS. Regulation of CXCR4 signaling in these cells may be involved in repair of the DG and may also give rise to ectopic granule cells in the DG in the context of neuropathology. PMID:25656357

  8. Identification of a sustained neurogenic zone at the dorsal surface of the adult mouse hippocampus and its regulation by the chemokine SDF-1.

    PubMed

    Belmadani, Abdelhak; Ren, Dongjun; Bhattacharyya, Bula J; Rothwangl, Katharina B; Hope, Thomas J; Perlman, Harris; Miller, Richard J

    2015-11-01

    We identified a previously unknown neurogenic region at the dorsal surface of the hippocampus; (the "subhippocampal zone," SHZ) in the adult brain. Using a reporter mouse in which SHZ cells and their progeny could be traced through the expression of EGFP under the control of the CXCR4 chemokine receptor promoter we observed the presence of a pool of EGFP expressing cells migrating in direction of the dentate gyrus (DG), which is maintained throughout adulthood. This population appeared to originate from the SHZ where cells entered a caudal migratory stream (aCMS) that included the fimbria, the meninges and the DG. Deletion of CXCR4 from neural stem cells (NSCs) or neuroinflammation resulted in the appearance of neurons in the DG, which were the result of migration of NSCs from the SHZ. Some of these neurons were ectopically placed. Our observations indicate that the SHZ is a neurogenic zone in the adult brain through migration of NSCs in the aCMS. Regulation of CXCR4 signaling in these cells may be involved in repair of the DG and may also give rise to ectopic granule cells in the DG in the context of neuropathology.

  9. The cyclophilin-binding agent Sanglifehrin A is a dendritic cell chemokine and migration inhibitor.

    PubMed

    Immecke, Sabrina N; Baal, Nelli; Wilhelm, Jochen; Bechtel, Juliane; Knoche, Angela; Bein, Gregor; Hackstein, Holger

    2011-01-01

    Sanglifehrin A (SFA) is a cyclophilin-binding immunosuppressant but the immunobiology of action is poorly understood. We and others have reported that SFA inhibits IL-12 production and antigen uptake in dendritic cells (DC) and exhibits lower activity against lymphocytes. Here we show that SFA suppresses DC chemokine production and migration. Gene expression analysis and subsequent protein level confirmation revealed that SFA suppressed CCL5, CCL17, CCL19, CXCL9 and CXCL10 expression in human monocyte-derived DC (moDC). A systems biology analysis, Onto Express, confirmed that SFA interferes with chemokine-chemokine receptor gene expression with the highest impact. Direct comparison with the related agent cyclosporine A (CsA) and dexamethasone indicated that SFA uniquely suppresses moDC chemokine expression. Competitive experiments with a 100-fold molar excess of CsA and with N-Methyl-Val-4-cyclosporin, representing a nonimmunosuppressive derivative of CsA indicated chemokine suppression through a cyclophilin-A independent pathway. Functional assays confirmed reduced migration of CD4+ Tcells and moDCs to supernatant of SFA-exposed moDCs. Vice versa, SFA-exposed moDC exhibited reduced migration against CCL19. Moreover, SFA suppressed expression of the ectoenzyme CD38 that was reported to regulate DC migration and cytokine production. These results identify SFA as a DC chemokine and migration inhibitor and provide novel insight into the immunobiology of SFA. PMID:21483789

  10. The Cyclophilin-Binding Agent Sanglifehrin A Is a Dendritic Cell Chemokine and Migration Inhibitor

    PubMed Central

    Immecke, Sabrina N.; Baal, Nelli; Wilhelm, Jochen; Bechtel, Juliane; Knoche, Angela; Bein, Gregor; Hackstein, Holger

    2011-01-01

    Sanglifehrin A (SFA) is a cyclophilin-binding immunosuppressant but the immunobiology of action is poorly understood. We and others have reported that SFA inhibits IL-12 production and antigen uptake in dendritic cells (DC) and exhibits lower activity against lymphocytes. Here we show that SFA suppresses DC chemokine production and migration. Gene expression analysis and subsequent protein level confirmation revealed that SFA suppressed CCL5, CCL17, CCL19, CXCL9 and CXCL10 expression in human monocyte-derived DC (moDC). A systems biology analysis, Onto Express, confirmed that SFA interferes with chemokine-chemokine receptor gene expression with the highest impact. Direct comparison with the related agent cyclosporine A (CsA) and dexamethasone indicated that SFA uniquely suppresses moDC chemokine expression. Competitive experiments with a 100-fold molar excess of CsA and with N-Methyl-Val-4-cyclosporin, representing a nonimmunosuppressive derivative of CsA indicated chemokine suppression through a cyclophilin-A independent pathway. Functional assays confirmed reduced migration of CD4+ Tcells and moDCs to supernatant of SFA-exposed moDCs. Vice versa, SFA-exposed moDC exhibited reduced migration against CCL19. Moreover, SFA suppressed expression of the ectoenzyme CD38 that was reported to regulate DC migration and cytokine production. These results identify SFA as a DC chemokine and migration inhibitor and provide novel insight into the immunobiology of SFA. PMID:21483789

  11. A specific PTPRC/CD45 phosphorylation event governed by stem cell chemokine CXCL12 regulates primitive hematopoietic cell motility.

    PubMed

    Williamson, Andrew J K; Pierce, Andrew; Jaworska, Ewa; Zhou, Cong; Aspinall-O'Dea, Mark; Lancashire, Lee; Unwin, Richard D; Abraham, Sheela A; Walker, Michael J; Cadecco, Sara; Spooncer, Elaine; Holyoake, Tessa L; Whetton, Anthony D

    2013-11-01

    CXCL12 governs cellular motility, a process deregulated by hematopoietic stem cell oncogenes such as p210-BCR-ABL. A phosphoproteomics approach to the analysis of a hematopoietic progenitor cell line treated with CXCL12 and the Rac 1 and 2 inhibitor NSC23766 has been employed to objectively discover novel mechanisms for regulation of stem cells in normal and malignant hematopoiesis. The proteomic data sets identified new aspects of CXCL12-mediated signaling and novel features of stem cell regulation. We also identified a novel phosphorylation event in hematopoietic progenitor cells that correlated with motile response and governed by the chemotactic factor CXCL12. The novel phosphorylation site on PTPRC/CD45; a protein tyrosine phosphatase, was validated by raising an antibody to the site and also using a mass spectrometry absolute quantification strategy. Site directed mutagenesis and inhibitor studies demonstrated that this single phosphorylation site governs hematopoietic progenitor cell and lymphoid cell motility, lies downstream from Rac proteins and potentiates Src signaling. We have also demonstrated that PTPRC/CD45 is down-regulated in leukemogenic tyrosine kinase expressing cells. The use of discovery proteomics has enabled further understanding of the regulation of PTPRC/CD45 and its important role in cellular motility in progenitor cells.

  12. Chemokines in CNS injury and repair.

    PubMed

    Jaerve, Anne; Müller, Hans Werner

    2012-07-01

    Recruitment of inflammatory cells is known to drive the secondary damage cascades that are common to injuries of the central nervous system (CNS). Cell activation and infiltration to the injury site is orchestrated by changes in the expression of chemokines, the chemoattractive cytokines. Reducing the numbers of recruited inflammatory cells by the blocking of the action of chemokines has turned out be a promising approach to diminish neuroinflammation and to improve tissue preservation and neovascularization. In addition, several chemokines have been shown to be essential for stem/progenitor cell attraction, their survival, differentiation and cytokine production. Thus, chemokines might indirectly participate in remyelination, neovascularization and neuroprotection, which are important prerequisites for CNS repair after trauma. Moreover, CXCL12 promotes neurite outgrowth in the presence of growth inhibitory CNS myelin and enhances axonal sprouting after spinal cord injury (SCI). Here, we review current knowledge about the exciting functions of chemokines in CNS trauma, including SCI, traumatic brain injury and stroke. We identify common principles of chemokine action and discuss the potentials and challenges of therapeutic interventions with chemokines. PMID:22700007

  13. Regulation of inflammasome activation

    PubMed Central

    Man, Si Ming; Kanneganti, Thirumala-Devi

    2015-01-01

    Summary Inflammasome biology is one of the most exciting and rapidly growing areas in immunology. Over the past 10 years, inflammasomes have been recognized for their roles in the host defense against invading pathogens and in the development of cancer, autoinflammatory, metabolic, and neurodegenerative diseases. Assembly of an inflammasome complex requires cytosolic sensing of pathogen-associated molecular patterns or danger-associated molecular patterns by a nucleotide-binding domain and leucine-rich repeat receptor (NLR) or absent in melanoma 2-like receptor (ALR). NLRs and ALRs engage caspase-1, in most cases requiring the adapter protein apoptosis-associated speck-like protein containing a CARD (ASC), to catalyze proteolytic cleavage of pro-interleukin-1β (pro-IL-1β) and pro-IL-18 and drive pyroptosis. Recent studies indicate that caspase-8, caspase-11, IL-1R–associated kinases (IRAK), and receptor-interacting protein (RIP) kinases contribute to inflammasome functions. In addition, post-translational modifications, including ubiquitination, deubiquitination, phosphorylation, and degradation, control almost every aspect of inflammasome activities. Genetic studies indicate that mutations in NLRP1, NLRP3, NLRC4, and AIM2 are linked to the development of autoinflammatory diseases, enterocolitis, and cancer. Overall, these findings transform our understanding of the basic biology and clinical relevance of inflammasomes. In this review, we provide an overview of the latest development of inflammasome research and discuss how inflammasome activities govern health and disease. PMID:25879280

  14. Characterization and expression analysis of an interferon-γ2 induced chemokine receptor CXCR3 in common carp (Cyprinus carpio L.).

    PubMed

    Chadzinska, M; Golbach, L; Pijanowski, L; Scheer, M; Verburg-van Kemenade, B M L

    2014-11-01

    Chemokine and chemokine receptor signalling pairs play a crucial role in regulation of cell migration, morphogenesis, and cell activation. Expressed in mammals on activated T and NK cells, chemokine receptor CXCR3 binds interferon-γ inducible chemokines CXCL9-11 and CCL21. Here we sequenced the carp CXCR3 chemokine receptor and showed its relationship to CXCR3a receptors found in other teleosts. We found high expression of the CXCR3 gene in most of the organs and tissues of the immune system and in immune-related tissues such as gills and gut, corroborating a predominantly immune-related function. The very high expression in gill and gut moreover indicates a role for CXCR3 in cell recruitment during infection. High in vivo expression of CXCR3 at later stages of inflammation, as well as its in vitro sensitivity to IFN-γ2 stimulation indicate that in carp, CXCR3 is involved in macrophage-mediated responses. Moreover, as expression of the CXCR3 and CXCb genes coincides in the focus of inflammation and as both the CXCb chemokines and the CXCR3 receptor are significantly up-regulated upon IFN-γ stimulation it is hypothesized that CXCb chemokines may be putative ligands for CXCR3. PMID:25036761

  15. Chemokine-coupled β2 integrin–induced macrophage Rac2–Myosin IIA interaction regulates VEGF-A mRNA stability and arteriogenesis

    PubMed Central

    Morrison, Alan R.; Yarovinsky, Timur O.; Young, Bryan D.; Moraes, Filipa; Ross, Tyler D.; Ceneri, Nicolle; Zhang, Jiasheng; Zhuang, Zhen W.; Sinusas, Albert J.; Pardi, Ruggero; Schwartz, Martin A.; Simons, Michael

    2014-01-01

    Myeloid cells are important contributors to arteriogenesis, but their key molecular triggers and cellular effectors are largely unknown. We report, in inflammatory monocytes, that the combination of chemokine receptor (CCR2) and adhesion receptor (β2 integrin) engagement leads to an interaction between activated Rac2 and Myosin 9 (Myh9), the heavy chain of Myosin IIA, resulting in augmented vascular endothelial growth factor A (VEGF-A) expression and induction of arteriogenesis. In human monocytes, CCL2 stimulation coupled to ICAM-1 adhesion led to rapid nuclear-to-cytosolic translocation of the RNA-binding protein HuR. This activation of HuR and its stabilization of VEGF-A mRNA were Rac2-dependent, and proteomic analysis for Rac2 interactors identified the 226 kD protein Myh9. The level of induced Rac2–Myh9 interaction strongly correlated with the degree of HuR translocation. CCL2-coupled ICAM-1 adhesion-driven HuR translocation and consequent VEGF-A mRNA stabilization were absent in Myh9−/− macrophages. Macrophage VEGF-A production, ischemic tissue VEGF-A levels, and flow recovery to hind limb ischemia were impaired in myeloid-specific Myh9−/− mice, despite preserved macrophage recruitment to the ischemic muscle. Micro-CT arteriography determined the impairment to be defective induced arteriogenesis, whereas developmental vasculogenesis was unaffected. These results place the macrophage at the center of ischemia-induced arteriogenesis, and they establish a novel role for Myosin IIA in signal transduction events modulating VEGF-A expression in tissue. PMID:25180062

  16. Mechanisms and implications of air pollution particle associations with chemokines

    SciTech Connect

    Seagrave, JeanClare

    2008-11-01

    Inflammation induced by inhalation of air pollutant particles has been implicated as a mechanism for the adverse health effects associated with exposure to air pollution. The inflammatory response is associated with upregulation of various pro-inflammatory cytokines and chemokines. We have previously shown that diesel exhaust particles (DEP), a significant constituent of air pollution particulate matter in many urban areas, bind and concentrate IL-8, an important human neutrophil-attracting chemokine, and that the chemokine remains biologically active. In this report, we examine possible mechanisms of this association and the effects on clearance of the chemokine. The binding appears to be the result of ionic interactions between negatively charged particles and positively charged chemokine molecules, possibly combined with intercalation into small pores in the particles. The association is not limited to diesel exhaust particles and IL-8: several other particle types also adsorb the chemokine and several other cytokines are adsorbed onto the diesel particles. However, there are wide ranges in the effectiveness of various particle types and various cytokines. Finally, male Fisher 344 rats were intratracheally instilled with chemokine alone or combined with diesel exhaust or silica particles under isofluorane anesthesia. In contrast to silica particles, which do not bind the chemokine, the presence of diesel exhaust particles, which bind the chemokine, prolonged the retention of the chemokine.

  17. Mechanisms and Implications of Air Pollution Particle Associations with Chemokines

    PubMed Central

    Seagrave, JeanClare

    2008-01-01

    Inflammation induced by inhalation of air pollutant particles has been implicated as a mechanism for the adverse health effects associated with exposure to air pollution. The inflammatory response is associated with upregulation of various pro-inflammatory cytokines and chemokines. We have previously shown that diesel exhaust particles (DEP), a significant constituent of air pollution particulate matter in many urban areas, bind and concentrate IL-8, an important human neutrophil-attracting chemokine, and that the chemokine remains biologically active. In this report, we examine possible mechanisms of this association and the effects on clearance of the chemokine. The binding appears to be the result of ionic interactions between negatively charged particles and positively charged chemokine molecules, possibly combined with intercalation into small pores in the particles. The association is not limited to diesel exhaust particles and IL-8: several other particle types also adsorb the chemokine and several other cytokines are adsorbed onto the diesel particles. However, there are wide ranges in the effectiveness of various particle types and various cytokines. Finally, male Fisher 344 rats were intratracheally instilled with chemokine alone or combined with diesel exhaust or silica particles under isofluorane anesthesia. In contrast to silica particles, which do not bind the chemokine, the presence of diesel exhaust particles, which bind the chemokine, prolonged the retention of the chemokine. PMID:18755206

  18. mTORC2-PKBα/Akt1 Serine 473 phosphorylation axis is essential for regulation of FOXP3 Stability by chemokine CCL3 in psoriasis.

    PubMed

    Chen, Ling; Wu, Jinjin; Pier, Eric; Zhao, Yun; Shen, Zhu

    2013-02-01

    The connection between infections and acute guttate psoriasis (AGP) outbreaks/chronic plaque psoriasis (CPP) exacerbation has been known for years. Impaired function of FOXP3+Tregs in psoriasis has been identified. However, the mechanisms behind these two observations have not been fully interpreted. In the present study, we provide evidence to support chemokine CCL3 as one of the vital links between infections and FOXP3 stability in the psoriatic microenvironment. We found that serum CCL3, strongly induced by microorganism infections including streptococcus, was closely correlated with FOXP3 levels in CD4+CD25+T cells of patients with psoriasis. CCL3 manipulated FOXP3 stability in a concentration-dependent bidirectional manner. High-concentration CCL3 decreased FOXP3 stability by promoting FOXP3's degradation through K48-linkage ubiquitination. This degradation was mainly dependent on upregulation of Serine 473 phosphorylation of the PKBα/Akt1 isoform, and almost independent of mTORC1 (mammalian target of rapamycin complex 1) activity. On the other hand, low-concentration CCL3 could enhance FOXP3 stability by the maintenance of the PKC pathway and the restriction of the PKB/Akt pathway. We further demonstrated that enhancing FOXP3 stability by low-concentration CCL3 attributed, at least partly, to the prevention of cytoplasmic Sin1, a vital component of mTORC2, nuclear translocation. Our results suggest vital roles for CCL3-mTORC2-isoform PKB/Akt1 S473 phosphorylation axis in FOXP3+Tregs and the development of psoriasis.

  19. Molecular Basis of Chemokine CXCL5-Glycosaminoglycan Interactions.

    PubMed

    Sepuru, Krishna Mohan; Nagarajan, Balaji; Desai, Umesh R; Rajarathnam, Krishna

    2016-09-23

    Chemokines, a large family of highly versatile small soluble proteins, play crucial roles in defining innate and adaptive immune responses by regulating the trafficking of leukocytes, and also play a key role in various aspects of human physiology. Chemokines share the characteristic feature of reversibly existing as monomers and dimers, and their functional response is intimately coupled to interaction with glycosaminoglycans (GAGs). Currently, nothing is known regarding the structural basis or molecular mechanisms underlying CXCL5-GAG interactions. To address this missing knowledge, we characterized the interaction of a panel of heparin oligosaccharides to CXCL5 using solution NMR, isothermal titration calorimetry, and molecular dynamics simulations. NMR studies indicated that the dimer is the high-affinity GAG binding ligand and that lysine residues from the N-loop, 40s turn, β3 strand, and C-terminal helix mediate binding. Isothermal titration calorimetry indicated a stoichiometry of two oligosaccharides per CXCL5 dimer. NMR-based structural models reveal that these residues form a contiguous surface within a monomer and, interestingly, that the GAG-binding domain overlaps with the receptor-binding domain, indicating that a GAG-bound chemokine cannot activate the receptor. Molecular dynamics simulations indicate that the roles of the individual lysines are not equivalent and that helical lysines play a more prominent role in determining binding geometry and affinity. Further, binding interactions and GAG geometry in CXCL5 are novel and distinctly different compared with the related chemokines CXCL1 and CXCL8. We conclude that a finely tuned balance between the GAG-bound dimer and free soluble monomer regulates CXCL5-mediated receptor signaling and function.

  20. Molecular Basis of Chemokine CXCL5-Glycosaminoglycan Interactions.

    PubMed

    Sepuru, Krishna Mohan; Nagarajan, Balaji; Desai, Umesh R; Rajarathnam, Krishna

    2016-09-23

    Chemokines, a large family of highly versatile small soluble proteins, play crucial roles in defining innate and adaptive immune responses by regulating the trafficking of leukocytes, and also play a key role in various aspects of human physiology. Chemokines share the characteristic feature of reversibly existing as monomers and dimers, and their functional response is intimately coupled to interaction with glycosaminoglycans (GAGs). Currently, nothing is known regarding the structural basis or molecular mechanisms underlying CXCL5-GAG interactions. To address this missing knowledge, we characterized the interaction of a panel of heparin oligosaccharides to CXCL5 using solution NMR, isothermal titration calorimetry, and molecular dynamics simulations. NMR studies indicated that the dimer is the high-affinity GAG binding ligand and that lysine residues from the N-loop, 40s turn, β3 strand, and C-terminal helix mediate binding. Isothermal titration calorimetry indicated a stoichiometry of two oligosaccharides per CXCL5 dimer. NMR-based structural models reveal that these residues form a contiguous surface within a monomer and, interestingly, that the GAG-binding domain overlaps with the receptor-binding domain, indicating that a GAG-bound chemokine cannot activate the receptor. Molecular dynamics simulations indicate that the roles of the individual lysines are not equivalent and that helical lysines play a more prominent role in determining binding geometry and affinity. Further, binding interactions and GAG geometry in CXCL5 are novel and distinctly different compared with the related chemokines CXCL1 and CXCL8. We conclude that a finely tuned balance between the GAG-bound dimer and free soluble monomer regulates CXCL5-mediated receptor signaling and function. PMID:27471273

  1. CXC chemokines and chemokine receptors in gastric cancer: From basic findings towards therapeutic targeting

    PubMed Central

    Lee, Hyo Jin; Song, Ik-Chan; Yun, Hwan-Jung; Jo, Deog-Yeon; Kim, Samyong

    2014-01-01

    Gastric cancer is the fourth most common cancer, and the second-highest cause of cancer-related deaths worldwide. Despite extensive research to identify novel diagnostic and therapeutic agents, patients with advanced gastric cancer suffer from a poor quality of life and poor prognosis, and treatment is dependent mainly on conventional cytotoxic chemotherapy. To improve the quality of life and survival of gastric cancer patients, a better understanding of the underlying molecular pathologies, and their application towards the development of novel targeted therapies, is urgently needed. Chemokines are a group of small proteins associated with cytoskeletal rearrangements, the directional migration of several cell types during development and physiology, and the host immune response via interactions with G-protein coupled receptors. There is also growing evidence to suggest that chemokines not only play a role in the immune system, but are also involved in the development and progression of tumors. In gastric cancer, CXC chemokines and chemokine receptors regulate the trafficking of cells in and out of the tumor microenvironment. CXC chemokines and their receptors can also directly influence tumorigenesis by modulating tumor transformation, survival, growth, invasion and metastasis, as well as indirectly by regulating angiogenesis, and tumor-leukocyte interactions. In this review, we will focus on the roles of CXC chemokines and their receptors in the development, progression, and metastasis of gastric tumors, and discuss their therapeutic potential for gastric cancer. PMID:24587647

  2. CXC and CC chemokines as angiogenic modulators in nonhaematological tumors.

    PubMed

    Santoni, Matteo; Bracarda, Sergio; Nabissi, Massimo; Massari, Francesco; Conti, Alessandro; Bria, Emilio; Tortora, Giampaolo; Santoni, Giorgio; Cascinu, Stefano

    2014-01-01

    Chemokines are a superfamily of structurally homologous heparin-binding proteins that includes potent inducers and inhibitors of angiogenesis. The imbalance between angiogenic and angiostatic chemokine activities can lead to abnormalities, such as chronic inflammation, dysplastic transformation, and even tumor development and spreading. In this review, we summarize the current literature regarding the role of chemokines as modulators of tumor angiogenesis and their potential role as therapeutic targets in patients with nonhaematological tumors.

  3. CXC and CC Chemokines as Angiogenic Modulators in Nonhaematological Tumors

    PubMed Central

    Bracarda, Sergio; Nabissi, Massimo; Massari, Francesco; Bria, Emilio; Tortora, Giampaolo; Santoni, Giorgio; Cascinu, Stefano

    2014-01-01

    Chemokines are a superfamily of structurally homologous heparin-binding proteins that includes potent inducers and inhibitors of angiogenesis. The imbalance between angiogenic and angiostatic chemokine activities can lead to abnormalities, such as chronic inflammation, dysplastic transformation, and even tumor development and spreading. In this review, we summarize the current literature regarding the role of chemokines as modulators of tumor angiogenesis and their potential role as therapeutic targets in patients with nonhaematological tumors. PMID:24971349

  4. Profiling Heparin-Chemokine Interactions Using Synthetic Tools

    PubMed Central

    de Paz, Jose L.; Moseman, E. Ashley; Noti, Christian; Polito, Laura; von Andrian, Ulrich H.; Seeberger, Peter H.

    2009-01-01

    Glycosaminoglycans (GAGs), such as heparin or heparan sulfate, are required for the in vivo function of chemokines. Chemokines play a crucial role in the recruitment of leukocyte subsets to sites of inflammation and lymphocytes trafficking. GAG-chemokine interactions mediate cell migration and determine which leukocyte subsets enter tissues. Identifying the exact GAC sequences that bind to particular chemokines is key to understand chemokine function at the molecular level and develop strategies to interfere with chemokine-mediated processes. Here, we characterize the heparin binding profiles of eight chemokines (CCL21, IL-8, CXCL12, CXCL13, CCL19, CCL25, CCL28, and CXCL16) by employing heparin microarrays containing a small library of synthetic heparin oligosaccharides. The chemokines differ significantly in their interactions with heparin oligosaccharides: While some chemokines, (e.g., CCL21) strongly bind to a hexasaccharide containing the GlcNSO3(6-OSO3)-IdoA(2-OSO3) repeating unit, CCL19 does not bind and CXCL12 binds only weakly. The carbohydrate microarray binding results were validated by surface plasmon resonance experiments. In vitro chemotaxis assays revealed that dendrimers coated with the fully sulfated heparin hexasaccharide inhibit lymphocyte migration toward CCL21. Migration toward CXCL12 or CCL19 was not affected. These in vitro homing assays indicate that multivalent synthetic heparin dendrimers inhibit the migration of lymphocytes toward certain chemokine gradients by blocking the formation of a chemokine concentration gradient on GAG endothelial chains. These findings are in agreement with preliminary in vivo measurements of circulating lymphocytes. The results presented here contribute to the understanding of GAG-chemokine interactions, a first step toward the design of novel drugs that modulate chemokine activity. PMID:18030990

  5. CsCCL17, a CC chemokine of Cynoglossus semilaevis, induces leukocyte trafficking and promotes immune defense against viral infection.

    PubMed

    Hu, Yong-Hua; Zhang, Jian

    2015-08-01

    CC chemokines are the largest subfamily of chemokines, which are important components of the innate immune system. To date, sequences of several CC chemokines have been identified in half-smooth tongue sole (Cynoglossus semilaevis); however, the activities and functions of these putative chemokines remain unknown. Herein, we characterized a CC chemokine, CsCCL17, from tongue sole, and examined its activity. CsCCL17 contains a 303 bp open reading frame, which encodes a polypeptide of 100 amino acids with a molecular mass of 12 kDa CsCCL17 is phylogenetically related to the CCL17/22 group of CC chemokines and possesses the typical arrangement of four cysteines and an SCCR motif found in known CC chemokines. Under normal physiological conditions, CsCCL17 expression was detected in spleen, liver, heart, gill, head kidney, muscle, brain, and intestine. When the fish were infected by bacterial and viral pathogens, CsCCL17 expression was significantly up-regulated in a time-dependent manner. Chemotactic analysis showed that recombinant CsCCL17 (rCsCCL17) induced migration of peripheral blood leukocytes. A mutagenesis study showed that when the two cysteine residues in the SCCR motif were replaced by serine, no apparent chemotactic activity was observed in the mutant protein rCsCCL17M. rCsCCL17 enhanced the resistance of tongue sole against viral infection, but rCsCCL17M lacked this antiviral effect. Taken together, these findings indicate that CsCCL17 is a functional CC chemokine with the ability to recruit leukocytes and enhance host immune defense in a manner that requires the conserved SCCR motif.

  6. Chemokine-dependent T cell migration requires aquaporin-3–mediated hydrogen peroxide uptake

    PubMed Central

    Chikuma, Shunsuke; Sugiyama, Yoshinori; Kabashima, Kenji; Verkman, Alan S.; Inoue, Shintaro; Miyachi, Yoshiki

    2012-01-01

    Chemokine-dependent trafficking is indispensable for the effector function of antigen-experienced T cells during immune responses. In this study, we report that the water/glycerol channel aquaporin-3 (AQP3) is expressed on T cells and regulates their trafficking in cutaneous immune reactions. T cell migration toward chemokines is dependent on AQP3-mediated hydrogen peroxide (H2O2) uptake but not the canonical water/glycerol transport. AQP3-mediated H2O2 transport is essential for the activation of the Rho family GTPase Cdc42 and the subsequent actin dynamics. Coincidentally, AQP3-deficient mice are defective in the development of hapten-induced contact hypersensitivity, which is attributed to the impaired trafficking of antigen-primed T cells to the hapten-challenged skin. We therefore suggest that AQP3-mediated H2O2 uptake is required for chemokine-dependent T cell migration in sufficient immune response. PMID:22927550

  7. Adrenocortical Activity and Emotion Regulation.

    ERIC Educational Resources Information Center

    Stansbury, Kathy; Gunnar, Megan R.

    1994-01-01

    This essay argues that the activity of the hypothalamic-pituitary-adrenocortical (HPA) system does not appear to be related to emotion regulation processes in children, although individual differences in emotion processes related to negative emotion temperaments appear to be associated with individual differences in HPA reactivity among normally…

  8. Myocardin Regulates Vascular Smooth Muscle Cell Inflammatory Activation and Disease

    PubMed Central

    Ackers-Johnson, Matthew; Talasila, Amarnath; Sage, Andrew P; Long, Xiaochun; Bot, Ilze; Morrell, Nicholas W; Bennett, Martin R; Miano, Joseph M.; Sinha, Sanjay

    2015-01-01

    Objective Atherosclerosis, the cause of 50% of deaths in westernised societies, is widely regarded as a chronic vascular inflammatory disease. Vascular smooth muscle cell (VSMC) inflammatory activation in response to local pro-inflammatory stimuli contributes to disease progression and is a pervasive feature in developing atherosclerotic plaques. Therefore, it is of considerable therapeutic importance to identify mechanisms that regulate the VSMC inflammatory response. Approach and Results We report that myocardin, a powerful myogenic transcriptional coactivator, negatively regulates VSMC inflammatory activation and vascular disease. Myocardin levels are reduced during atherosclerosis, in association with phenotypic switching of smooth muscle cells. Myocardin deficiency accelerates atherogenesis in hypercholesterolemic ApoE−/− mice. Conversely, increased myocardin expression potently abrogates the induction of an array of inflammatory cytokines, chemokines and adhesion molecules in VSMCs. Expression of myocardin in VSMCs reduces lipid uptake, macrophage interaction, chemotaxis and macrophage-endothelial tethering in vitro, and attenuates monocyte accumulation within developing lesions in vivo. These results demonstrate that endogenous levels of myocardin are a critical regulator of vessel inflammation. Conclusions We propose myocardin as a guardian of the contractile, non-inflammatory VSMC phenotype, with loss of myocardin representing a critical permissive step in the process of phenotypic transition and inflammatory activation, at the onset of vascular disease. PMID:25614278

  9. Neutrophils regulate the expression of cytokines, chemokines and nitric oxide synthase/nitric oxide in mice injected with Bothrops atrox venom.

    PubMed

    Escocard, Rita de Cássia Mothé; Kanashiro, Milton Masahiko; Petretski, Jorge Hudson; Azevedo-Silva, Juliana; Queiroz de Carvalho, Eulógio Carlos; Dias da Silva, Wilmar; Kipnis, Thereza Liberman

    2006-01-01

    Bothrops atrox crude venom injected intraperitoneal (i.p.) into BALB/c mice induced local afflux of inflammatory cells, one neutrophil-rich peak after 6h and another macrophage-rich peak after 48 h. A similar pattern of local cell afflux plus edema, Delta lesions of some skeletal muscle cells, and hemorrhage were observed in mice intramuscular (i.m.) injected with the venom. Measurement of serum cytokines in neutrophil-depleted (by anti-mouse rat monoclonal antibody (mAb) RB6-8C5) and non-depleted BALB/c mice was performed by ELISA. With the exception of IL-1beta (78 pg/ml), higher levels of IL-6 (1348 pg/ml), MIP-1beta (437 pg/ml) and MIP-2 (904 pg/ml) were observed in neutrophil-depleted mice, in comparison to the values found in non-neutrophil depleted mice: IL-1beta (437 pg/ml), IL-6 (750 pg/ml), MIP-1beta (165 pg/ml) and MIP-2 (90 pg/ml). TNF-alpha was not detected. NO was detected (18 microM) 24h after venom injection in neutrophil-depleted mice. RT-PCR using representative primers detected expression of mRNA in cells from BALB/c mice injected with B. atrox venom: (a) for IL-1beta, IL-6, inducible nitric oxide synthase (iNOS), CXCR2, MIP-2 and RANTES in cells from mice that were neutrophil-depleted or not; (b) for CCR1, CCR5 and MIP-1beta in cells from neutrophil-depleted mice; (c) for MIP-1alpha in cells from non-neutrophil-depleted mice; (d) TNF-alpha and TGF-beta were not detected in either of the mice. These results indicate that neutrophils play a role in regulating the production of some cytokines and chemokines as well as locally expressed or liberated iNOS/NO in tissues injected with B. atrox crude venom. PMID:16446169

  10. Chemokines: established and novel targets in atherosclerosis

    PubMed Central

    Koenen, Rory R; Weber, Christian

    2011-01-01

    In their role as small chemotactic cytokines, chemokines are crucial mediators and regulators of leukocyte trafficking during immune surveillance and inflammation. Their involvement in the development and progression of inflammatory diseases has been subject of intense investigation. Concordantly, the chemokine system has been explored in search for therapeutic targets to prevent or treat inflammatory disorders, such as atherosclerosis. Targeting the chemokine system offers various entry points for a causative treatment of this widespread and chronic illness. Although this approach has encountered some setbacks, several innovative compounds are currently in an advanced stage of development. In this review, the current standing of this dynamic field is highlighted and the potential advantages and drawbacks of particular strategies are discussed. PMID:22038924

  11. Chemokines and Chemokine Receptors in the Development of Lupus Nephritis

    PubMed Central

    2016-01-01

    Lupus nephritis (LN) is a major cause of morbidity and mortality in the patients with systemic lupus erythematosus (SLE), an autoimmune disease with damage to multiple organs. Leukocyte recruitment into the inflamed kidney is a critical step to promote LN progression, and the chemokine/chemokine receptor system is necessary for leukocyte recruitment. In this review, we summarize recent studies on the roles of chemokines and chemokine receptors in the development of LN and discuss the potential and hurdles of developing novel, chemokine-based drugs to treat LN. PMID:27403037

  12. Systemic chemokine levels, coronary heart disease, and ischemic stroke events

    PubMed Central

    Canouï-Poitrine, F.; Luc, G.; Mallat, Z.; Machez, E.; Bingham, A.; Ferrieres, J.; Ruidavets, J.-B.; Montaye, M.; Yarnell, J.; Haas, B.; Arveiler, D.; Morange, P.; Kee, F.; Evans, A.; Amouyel, P.; Ducimetiere, P.

    2011-01-01

    Objectives: To quantify the association between systemic levels of the chemokine regulated on activation normal T-cell expressed and secreted (RANTES/CCL5), interferon-γ-inducible protein-10 (IP-10/CXCL10), monocyte chemoattractant protein-1 (MCP-1/CCL2), and eotaxin-1 (CCL11) with future coronary heart disease (CHD) and ischemic stroke events and to assess their usefulness for CHD and ischemic stroke risk prediction in the PRIME Study. Methods: After 10 years of follow-up of 9,771 men, 2 nested case-control studies were built including 621 first CHD events and 1,242 matched controls and 95 first ischemic stroke events and 190 matched controls. Standardized hazard ratios (HRs) for each log-transformed chemokine were estimated by conditional logistic regression. Results: None of the 4 chemokines were independent predictors of CHD, either with respect to stable angina or to acute coronary syndrome. Conversely, RANTES (HR = 1.70; 95% confidence interval [CI] 1.05–2.74), IP-10 (HR = 1.53; 95% CI 1.06–2.20), and eotaxin-1 (HR = 1.59; 95% CI 1.02–2.46), but not MCP-1 (HR = 0.99; 95% CI 0.68–1.46), were associated with ischemic stroke independently of traditional cardiovascular risk factors, hs-CRP, and fibrinogen. When the first 3 chemokines were included in the same multivariate model, RANTES and IP-10 remained predictive of ischemic stroke. Their addition to a traditional risk factor model predicting ischemic stroke substantially improved the C-statistic from 0.6756 to 0.7425 (p = 0.004). Conclusions: In asymptomatic men, higher systemic levels of RANTES and IP-10 are independent predictors of ischemic stroke but not of CHD events. RANTES and IP-10 may improve the accuracy of ischemic stroke risk prediction over traditional risk factors. PMID:21849651

  13. An inflammatory CC chemokine of Cynoglossus semilaevis is involved in immune defense against bacterial infection.

    PubMed

    Li, Yong-xin; Sun, Jin-sheng; Sun, Li

    2011-09-01

    Chemokines are a family of small cytokines that regulate leukocyte migration. Based on the arrangement of the first two cysteine residues, chemokines are classified into four groups called CXC(α), CC(β), C, and CX(3)C. In this study, we identified a CC chemokine, CsCCK1, from half-smooth tongue sole (Cynoglossus semilaevis) and analyzed its biological activity. The deduced amino acid sequence of CsCCK1 contains 111 amino acid residues and is phylogenetically belonging to the CCL19/21/25 group of CC chemokines. CsCCK1 possesses a DCCL motif that is highly conserved among CC chemokines. Quantitative real time RT-PCR analysis showed that the expression of CsCCK1 was relatively abundant in immune organs under normal physiological conditions and was upregulated by experimental infection of a bacterial pathogen. Purified recombinant CsCCK1 (rCsCCK1) induced chemotaxis in peripheral blood leukocytes (PBL) of both tongue sole and turbot (Scophthalmus maximus) in a dose-dependent manner. Mutation of the CC residues in the DCCL motif by serine substitution completely abolished the biological activity of rCsCCK1. When rCsCCK1, but not the mutant protein, was added to the cell culture of PBL, it enhanced cellular resistance against intracellular bacterial infection. Taken together, these results indicate that CsCCK1 is a functional CC chemokine whose biological activity depends on the DCCL motif and that CsCCK1 plays a role in host immune defense against bacterial infection.

  14. Targeting of TGF-β-activated protein kinase 1 inhibits chemokine (C-C motif) receptor 7 expression, tumor growth and metastasis in breast cancer

    PubMed Central

    Hung, Wen-Chun; Hou, Ming-Feng

    2015-01-01

    TGF-β-activated protein kinase 1 (TAK1) is a critical mediator in inflammation, immune response and cancer development. Our previous study demonstrated that activation of TAK1 increases the expression of chemokine (C-C motif) receptor 7 (CCR7) and promotes lymphatic invasion ability of breast cancer cells. However, the expression and association of activated TAK1 and CCR7 in breast tumor tissues is unknown and the therapeutic effect by targeting TAK1 is also unclear. We showed that activated TAK1 (as indicated by phospho-TAK1) and its binding protein TAB1 are strongly expressed in breast tumor tissues (77% and 74% respectively). In addition, increase of phospho-TAK1 or TAB1 is strongly associated with over-expression of CCR7. TAK1 inhibitor 5Z-7-Oxozeaenol (5Z-O) inhibited TAK1 activity, suppressed downstream signaling pathways including p38, IκB kinase (IKK) and c-Jun N-terminal kinase (JNK) and reduced CCR7 expression in metastatic MDA-MB-231 cells. In addition, 5Z-O repressed NF-κB- and c-JUN-mediated transcription of CCR7 gene. Knockdown of TAB1 attenuated CCR7 expression and tumor growth in an orthotopic animal study. More importantly, lymphatic invasion and lung metastasis were suppressed. Collectively, our results demonstrate that constitutive activation of TAK1 is frequently found in human breast cancer and this kinase is a potential therapeutic target for this cancer. PMID:25557171

  15. Epac Activation Regulates Human Mesenchymal Stem Cells Migration and Adhesion.

    PubMed

    Yu, Jiao-Le; Deng, Ruixia; Chung, Sookja K; Chan, Godfrey Chi-Fung

    2016-04-01

    How to enhance the homing of human mesenchymal stem cells (hMSCs) to the target tissues remains a clinical challenge nowadays. To overcome this barrier, the mechanism responsible for the hMSCs migration and engraftment has to be defined. Currently, the exact mechanism involved in migration and adhesion of hMSCs remains unknown. Exchange protein directly activated by cAMP (Epac), a novel protein discovered in cAMP signaling pathway, may have a potential role in regulating cells adhesion and migration by triggering the downstream Rap family signaling cascades. However, the exact role of Epac in cells homing is elusive. Our study evaluated the role of Epac in the homing of hMSCs. We confirmed that hMSCs expressed functional Epac and its activation enhanced the migration and adhesion of hMSCs significantly. The Epac activation was further found to be contributed directly to the chemotactic responses induced by stromal cell derived factor-1 (SDF-1) which is a known chemokine in regulating hMSCs homing. These findings suggested Epac is connected to the SDF-1 signaling cascades. In conclusion, our study revealed that Epac plays a role in hMSCs homing by promoting adhesion and migration. Appropriate manipulation of Epac may enhance the homing of hMSCs and facilitate their future clinical applications. PMID:26727165

  16. Production of Recombinant Chemokines and Validation of Refolding.

    PubMed

    Veldkamp, Christopher T; Koplinski, Chad A; Jensen, Davin R; Peterson, Francis C; Smits, Kaitlin M; Smith, Brittney L; Johnson, Scott K; Lettieri, Christina; Buchholz, Wallace G; Solheim, Joyce C; Volkman, Brian F

    2016-01-01

    The diverse roles of chemokines in normal immune function and many human diseases have motivated numerous investigations into the structure and function of this family of proteins. Recombinant chemokines are often used to study how chemokines coordinate the trafficking of immune cells in various biological contexts. A reliable source of biologically active protein is vital for any in vitro or in vivo functional analysis. In this chapter, we describe a general method for the production of recombinant chemokines and robust techniques for efficient refolding that ensure consistently high biological activity. Considerations for initiating development of protocols consistent with Current Good Manufacturing Practices (cGMPs) to produce biologically active chemokines suitable for use in clinical trials are also discussed. PMID:26921961

  17. CC-Chemokine Ligand 2 (CCL2) Suppresses High Density Lipoprotein (HDL) Internalization and Cholesterol Efflux via CC-Chemokine Receptor 2 (CCR2) Induction and p42/44 Mitogen-activated Protein Kinase (MAPK) Activation in Human Endothelial Cells.

    PubMed

    Sun, Run-Lu; Huang, Can-Xia; Bao, Jin-Lan; Jiang, Jie-Yu; Zhang, Bo; Zhou, Shu-Xian; Cai, Wei-Bin; Wang, Hong; Wang, Jing-Feng; Zhang, Yu-Ling

    2016-09-01

    High density lipoprotein (HDL) has been proposed to be internalized and to promote reverse cholesterol transport in endothelial cells (ECs). However, the mechanism underlying these processes has not been studied. In this study, we aim to characterize HDL internalization and cholesterol efflux in ECs and regulatory mechanisms. We found mature HDL particles were reduced in patients with coronary artery disease (CAD), which was associated with an increase in CC-chemokine ligand 2 (CCL2). In cultured primary human coronary artery endothelial cells and human umbilical vein endothelial cells, we determined that CCL2 suppressed the binding (4 °C) and association (37 °C) of HDL to/with ECs and HDL cellular internalization. Furthermore, CCL2 inhibited [(3)H]cholesterol efflux to HDL/apoA1 in ECs. We further found that CCL2 induced CC-chemokine receptor 2 (CCR2) expression and siRNA-CCR2 reversed CCL2 suppression on HDL binding, association, internalization, and on cholesterol efflux in ECs. Moreover, CCL2 induced p42/44 mitogen-activated protein kinase (MAPK) phosphorylation via CCR2, and p42/44 MAPK inhibition reversed the suppression of CCL2 on HDL metabolism in ECs. Our study suggests that CCL2 was elevated in CAD patients. CCL2 suppressed HDL internalization and cholesterol efflux via CCR2 induction and p42/44 MAPK activation in ECs. CCL2 induction may contribute to impair HDL function and form atherosclerosis in CAD.

  18. CC-Chemokine Ligand 2 (CCL2) Suppresses High Density Lipoprotein (HDL) Internalization and Cholesterol Efflux via CC-Chemokine Receptor 2 (CCR2) Induction and p42/44 Mitogen-activated Protein Kinase (MAPK) Activation in Human Endothelial Cells *

    PubMed Central

    Sun, Run-Lu; Huang, Can-Xia; Bao, Jin-Lan; Jiang, Jie-Yu; Zhang, Bo; Zhou, Shu-Xian; Cai, Wei-Bin; Wang, Hong; Wang, Jing-Feng; Zhang, Yu-Ling

    2016-01-01

    High density lipoprotein (HDL) has been proposed to be internalized and to promote reverse cholesterol transport in endothelial cells (ECs). However, the mechanism underlying these processes has not been studied. In this study, we aim to characterize HDL internalization and cholesterol efflux in ECs and regulatory mechanisms. We found mature HDL particles were reduced in patients with coronary artery disease (CAD), which was associated with an increase in CC-chemokine ligand 2 (CCL2). In cultured primary human coronary artery endothelial cells and human umbilical vein endothelial cells, we determined that CCL2 suppressed the binding (4 °C) and association (37 °C) of HDL to/with ECs and HDL cellular internalization. Furthermore, CCL2 inhibited [3H]cholesterol efflux to HDL/apoA1 in ECs. We further found that CCL2 induced CC-chemokine receptor 2 (CCR2) expression and siRNA-CCR2 reversed CCL2 suppression on HDL binding, association, internalization, and on cholesterol efflux in ECs. Moreover, CCL2 induced p42/44 mitogen-activated protein kinase (MAPK) phosphorylation via CCR2, and p42/44 MAPK inhibition reversed the suppression of CCL2 on HDL metabolism in ECs. Our study suggests that CCL2 was elevated in CAD patients. CCL2 suppressed HDL internalization and cholesterol efflux via CCR2 induction and p42/44 MAPK activation in ECs. CCL2 induction may contribute to impair HDL function and form atherosclerosis in CAD. PMID:27458015

  19. Actions of Thyroid Hormone Analogues on Chemokines.

    PubMed

    Davis, Paul J; Glinsky, Gennadi V; Lin, Hung-Yun; Mousa, Shaker A

    2016-01-01

    The extracellular domain of plasma membrane integrin αvβ3 contains a receptor for thyroid hormone (L-thyroxine, T4; 3,5,3'-triiodo-L-thyronine, T3); this receptor also binds tetraiodothyroacetic acid (tetrac), a derivative of T4. Tetrac inhibits the binding of T4 and T3 to the integrin. Fractalkine (CX3CL1) is a chemokine relevant to inflammatory processes in the CNS that are microglia-dependent but also important to normal brain development. Expression of the CX3CL1 gene is downregulated by tetrac, suggesting that T4 and T3 may stimulate fractalkine expression. Independently of its specific receptor (CX3CR1), fractalkine binds to αvβ3 at a site proximal to the thyroid hormone-tetrac receptor and changes the physical state of the integrin. Tetrac also affects expression of the genes for other CNS-relevant chemokines, including CCL20, CCL26, CXCL2, CXCL3, and CXCL10. The chemokine products of these genes are important to vascularity of the brain, particularly of the choroid plexus, to inflammatory processes in the CNS and, in certain cases, to neuroprotection. Thyroid hormones are known to contribute to regulation of each of these CNS functions. We propose that actions of thyroid hormone and hormone analogues on chemokine gene expression contribute to regulation of inflammatory processes in brain and of brain blood vessel formation and maintenance. PMID:27493972

  20. Actions of Thyroid Hormone Analogues on Chemokines

    PubMed Central

    Glinsky, Gennadi V.

    2016-01-01

    The extracellular domain of plasma membrane integrin αvβ3 contains a receptor for thyroid hormone (L-thyroxine, T4; 3,5,3′-triiodo-L-thyronine, T3); this receptor also binds tetraiodothyroacetic acid (tetrac), a derivative of T4. Tetrac inhibits the binding of T4 and T3 to the integrin. Fractalkine (CX3CL1) is a chemokine relevant to inflammatory processes in the CNS that are microglia-dependent but also important to normal brain development. Expression of the CX3CL1 gene is downregulated by tetrac, suggesting that T4 and T3 may stimulate fractalkine expression. Independently of its specific receptor (CX3CR1), fractalkine binds to αvβ3 at a site proximal to the thyroid hormone-tetrac receptor and changes the physical state of the integrin. Tetrac also affects expression of the genes for other CNS-relevant chemokines, including CCL20, CCL26, CXCL2, CXCL3, and CXCL10. The chemokine products of these genes are important to vascularity of the brain, particularly of the choroid plexus, to inflammatory processes in the CNS and, in certain cases, to neuroprotection. Thyroid hormones are known to contribute to regulation of each of these CNS functions. We propose that actions of thyroid hormone and hormone analogues on chemokine gene expression contribute to regulation of inflammatory processes in brain and of brain blood vessel formation and maintenance. PMID:27493972

  1. Association of MIF, but not type I interferon-induced chemokines, with increased disease activity in Asian patients with systemic lupus erythematosus

    PubMed Central

    Connelly, K. L.; Kandane-Rathnayake, R.; Hoi, A.; Nikpour, Mandana; Morand, E. F.

    2016-01-01

    Ethnicity is a key factor impacting on disease severity in SLE, but molecular mechanisms of these associations are unknown. Type I IFN and MIF have each been associated with SLE pathogenesis. We investigated whether increased SLE severity in Asian patients is associated with either MIF or Type I IFN. SLE patients (n = 151) had prospective recording of disease variables. Serum MIF, and a validated composite score of three Type I IFN-inducible chemokines (IFNCK:CCL2, CXCL10, CCL19) were measured. Associations of MIF and IFNCK score with disease activity were assessed, with persistent active disease (PAD) used as a marker of high disease activity over a median 2.6 years follow up. In univariable analysis, MIF, IFNCK score and Asian ethnicity were significantly associated with PAD. Asian ethnicity was associated with higher MIF but not IFNCK score. In multivariable logistic regression analysis, MIF (OR3.62 (95% CI 1.14,11.5), p = 0.03) and Asian ethnicity (OR3.00 (95% CI 1.39,6.46), p < 0.01) but not IFNCK were significantly associated with PAD. These results potentially support an effect of MIF, but not Type I IFN, in heightened SLE disease severity in Asian SLE. The associations of MIF and Asian ethnicity with PAD are at least partly independent. PMID:27453287

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

    PubMed

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

    2016-09-01

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

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

    PubMed

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

    2016-09-01

    EGFR signaling regulates macrophage function, but its role in bacterial infection has not been investigated. Here, we assessed the role of macrophage EGFR signaling during infection with Helicobacter pylori, a bacterial pathogen that causes persistent inflammation and gastric cancer. EGFR was phosphorylated in murine and human macrophages during H. pylori infection. In human gastric tissues, elevated levels of phosphorylated EGFR were observed throughout the histologic cascade from gastritis to carcinoma. Deleting Egfr in myeloid cells attenuated gastritis and increased H. pylori burden in infected mice. EGFR deficiency also led to a global defect in macrophage activation that was associated with decreased cytokine, chemokine, and NO production. We observed similar alterations in macrophage activation and disease phenotype in the Citrobacter rodentium model of murine infectious colitis. Mechanistically, EGFR signaling activated NF-κB and MAPK1/3 pathways to induce cytokine production and macrophage activation. Although deletion of Egfr had no effect on DC function, EGFR-deficient macrophages displayed impaired Th1 and Th17 adaptive immune responses to H. pylori, which contributed to decreased chronic inflammation in infected mice. Together, these results indicate that EGFR signaling is central to macrophage function in response to enteric bacterial pathogens and is a potential therapeutic target for infection-induced inflammation and associated carcinogenesis. PMID:27482886

  4. Molecular Basis of Glycosaminoglycan Heparin Binding to the Chemokine CXCL1 Dimer*

    PubMed Central

    Poluri, Krishna Mohan; Joseph, Prem Raj B.; Sawant, Kirti V.; Rajarathnam, Krishna

    2013-01-01

    Glycosaminoglycan (GAG)-bound and soluble chemokine gradients in the vasculature and extracellular matrix mediate neutrophil recruitment to the site of microbial infection and sterile injury in the host tissue. However, the molecular principles by which chemokine-GAG interactions orchestrate these gradients are poorly understood. This, in part, can be directly attributed to the complex interrelationship between the chemokine monomer-dimer equilibrium and binding geometry and affinities that are also intimately linked to GAG length. To address some of this missing knowledge, we have characterized the structural basis of heparin binding to the murine CXCL1 dimer. CXCL1 is a neutrophil-activating chemokine and exists as both monomers and dimers (Kd = 36 μm). To avoid interference from monomer-GAG interactions, we designed a trapped dimer (dCXCL1) by introducing a disulfide bridge across the dimer interface. We characterized the binding of GAG heparin octasaccharide to dCXCL1 using solution NMR spectroscopy. Our studies show that octasaccharide binds orthogonally to the interhelical axis and spans the dimer interface and that heparin binding enhances the structural integrity of the C-terminal helical residues and stability of the dimer. We generated a quadruple mutant (H20A/K22A/K62A/K66A) on the basis of the binding data and observed that this mutant failed to bind heparin octasaccharide, validating our structural model. We propose that the stability enhancement of dimers upon GAG binding regulates in vivo neutrophil trafficking by increasing the lifetime of “active” chemokines, and that this structural knowledge could be exploited for designing inhibitors that disrupt chemokine-GAG interactions and neutrophil homing to the target tissue. PMID:23864653

  5. Differential Chemokine Signature between Human Preadipocytes and Adipocytes

    PubMed Central

    Ignacio, Rosa Mistica C.; Gibbs, Carla R.; Lee, Eun-Sook

    2016-01-01

    Obesity is characterized as an accumulation of adipose tissue mass represented by chronic, low-grade inflammation. Obesity-derived inflammation involves chemokines as important regulators contributing to the pathophysiology of obesity-related diseases such as cardiovascular disease, diabetes and some cancers. The obesity-driven chemokine network is poorly understood. Here, we identified the profiles of chemokine signature between human preadipocytes and adipocytes, using PCR arrays and qRT-PCR. Both preadipocytes and adipocytes showed absent or low levels in chemokine receptors in spite of some changes. On the other hand, the chemokine levels of CCL2, CCL7-8, CCL11, CXCL1-3, CXCL6 and CXCL10-11 were dominantly expressed in preadipocytes compared to adipocytes. Interestingly, CXCL14 was the most dominant chemokine expressed in adipocytes compared to preadipocytes. Moreover, there is significantly higher protein level of CXCL14 in conditioned media from adipocytes. In addition, we analyzed the data of the chemokine signatures in adipocytes obtained from healthy lean and obese postmenopausal women based on Gene Expression Omnibus (GEO) dataset. Adipocytes from obese individuals had significantly higher levels in chemokine signature as follows: CCL2, CCL13, CCL18-19, CCL23, CCL26, CXCL1, CXCL3 and CXCL14, as compared to those from lean ones. Also, among the chemokine networks, CXCL14 appeared to be the highest levels in adipocytes from both lean and obese women. Taken together, these results identify CXCL14 as an important chemokine induced during adipogenesis, requiring further research elucidating its potential therapeutic benefits in obesity. PMID:27340388

  6. Chemokine-guided cell migration and motility in zebrafish development.

    PubMed

    Bussmann, Jeroen; Raz, Erez

    2015-05-12

    Chemokines are vertebrate-specific, structurally related proteins that function primarily in controlling cell movements by activating specific 7-transmembrane receptors. Chemokines play critical roles in a large number of biological processes and are also involved in a range of pathological conditions. For these reasons, chemokines are at the focus of studies in developmental biology and of clinically oriented research aimed at controlling cancer, inflammation, and immunological diseases. The small size of the zebrafish embryos, their rapid external development, and optical properties as well as the large number of eggs and the fast expansion in genetic tools available make this model an extremely useful one for studying the function of chemokines and chemokine receptors in an in vivo setting. Here, we review the findings relevant to the role that chemokines play in the context of directed single-cell migration, primarily in neutrophils and germ cells, and compare it to the collective cell migration of the zebrafish lateral line. We present the current knowledge concerning the formation of the chemokine gradient, its interpretation within the cell, and the molecular mechanisms underlying the cellular response to chemokine signals during directed migration.

  7. Role of p38 MAPK and NF-kB for chemokine release in coculture of human eosinophils and bronchial epithelial cells.

    PubMed

    Wong, C K; Wang, C B; Ip, W K; Tian, Y P; Lam, C W K

    2005-01-01

    Eosinophils are principal effector cells of inflammation in allergic asthma, characterized by their accumulation and infiltration at inflammatory sites mediated by the chemokine eotaxin and their interaction with adhesion molecules expressed on bronchial epithelial cells. We investigated the modulation of nuclear factor-kappaB (NF-kappaB) and the mitogen-activated protein kinase (MAPK) pathway on the in vitro release of chemokines including regulated upon activation normal T cell expressed and secreted (RANTES), monokine induced by interferon-gamma (MIG), monocyte chemoattractant protein-1 (MCP-1), interleukin (IL)-8, and interferon-inducible protein-10 (IP-10) upon the interaction of human bronchial epithelial BEAS-2B cells and eosinophils. Gene expression of chemokines was evaluated by RT-PCR and the induction amount of chemokines quantified by cytometric bead array. NF-kappaB and p38 MAPK activities were assessed by electrophoretic mobility shift assay and Western blot, respectively. The interaction of eosinophils and BEAS-2B cells was found to up-regulate the gene expression of the chemokines IL-8, MCP-1, MIG, RANTES and IP-10 expression in BEAS-2B cells, and to significantly elevate the release of the aforementioned chemokines except RANTES in a coculture of BEAS-2B cells and eosinophils. IkappaB-alpha phosphorylation inhibitor, BAY 11-7082, and p38 MAPK inhibitor, SB 203580 could decrease the release of IL-8, IP-10 and MCP-1 in the coculture. Together, the above results show that the induction of the release of chemokines in a coculture of epithelial cells and eosinophils are regulated by p38 MAPK and NF-kappaB activities of BEAS-2B cells, at least partly, through intercellular contact. Our findings therefore shed light on the future development of more effective agents for allergic and inflammatory diseases.

  8. Chemokines in cancer related inflammation

    SciTech Connect

    Allavena, Paola; Germano, Giovanni; Marchesi, Federica; Mantovani, Alberto

    2011-03-10

    Chemokines are key players of the cancer-related inflammation. Chemokine ligands and receptors are downstream of genetic events that cause neoplastic transformation and are abundantly expressed in chronic inflammatory conditions which predispose to cancer. Components of the chemokine system affect multiple pathways of tumor progression including: leukocyte recruitment, neo-angiogenesis, tumor cell proliferation and survival, invasion and metastasis. Evidence in pre-clinical and clinical settings suggests that the chemokine system represents a valuable target for the development of innovative therapeutic strategies.

  9. Chemokines, costimulatory molecules and fusion proteins for the immunotherapy of solid tumors.

    PubMed

    Lechner, Melissa G; Russell, Sarah M; Bass, Rikki S; Epstein, Alan L

    2011-11-01

    In this article, the role of chemokines and costimulatory molecules in the immunotherapy of experimental murine solid tumors and immunotherapy used in ongoing clinical trials are presented. Chemokine networks regulate physiologic cell migration that may be disrupted to inhibit antitumor immune responses or co-opted to promote tumor growth and metastasis in cancer. Recent studies highlight the potential use of chemokines in cancer immunotherapy to improve innate and adaptive cell interactions and to recruit immune effector cells into the tumor microenvironment. Another critical component of antitumor immune responses is antigen priming and activation of effector cells. Reciprocal expression and binding of costimulatory molecules and their ligands by antigen-presenting cells and naive lymphocytes ensures robust expansion, activity and survival of tumor-specific effector cells in vivo. Immunotherapy approaches using agonist antibodies or fusion proteins of immunomodulatory molecules significantly inhibit tumor growth and boost cell-mediated immunity. To localize immune stimulation to the tumor site, a series of fusion proteins consisting of a tumor-targeting monoclonal antibody directed against tumor necrosis and chemokines or costimulatory molecules were generated and tested in tumor-bearing mice. While several of these reagents were initially shown to have therapeutic value, combination therapies with methods to delete suppressor cells had the greatest effect on tumor growth. In conclusion, a key conclusion that has emerged from these studies is that successful immunotherapy will require both advanced methods of immunostimulation and the removal of immunosuppression in the host.

  10. Chemokine interaction with synergy-inducing molecules: fine tuning modulation of cell trafficking

    PubMed Central

    Cecchinato, Valentina; D’Agostino, Gianluca; Raeli, Lorenzo; Uguccioni, Mariagrazia

    2016-01-01

    Directed migration and arrest of leukocytes during homeostasis, inflammation, and tumor development is mediated by the chemokine system, which governs leukocyte migration and activities. Although we understand well the effects of different chemokines one by one, much less was known about the potential consequences of the concomitant expression of multiple chemokines or of their interaction with inflammatory molecules on leukocyte migration and functions. In the past 10 yr, several studies revealed the existence of additional features of chemokines: they can antagonize chemokine receptors or synergize with other chemokines, also by forming heterocomplexes. Moreover, recent data show that not only chemokines but also the alarmin high-mobility group box 1 can for a complex with CXCL12, enhancing its potency on CXCR4. The molecular mechanism underlying the effect of the heterocomplex has been partially elucidated, whereas its structure is a matter of current investigations. The present review discusses the current knowledge and relevance of the functions of heterocomplexes formed between chemokines or between the chemokine CXCL12 and the alarmin high-mobility group box 1. These studies highlight the importance of taking into account, when approaching innovative therapies targeting the chemokine system, also the fact that some chemokines and molecules released in inflammation, can considerably affect the activity of chemokine receptor agonists. PMID:26715684

  11. Cytokine and chemokine expression profiles in response to Mycobacterium tuberculosis stimulation are altered in HIV-infected compared to HIV-uninfected subjects with active tuberculosis.

    PubMed

    Waruk, Jillian L M; Machuki, Zipporah; Mesa, Christine; Juno, Jennifer A; Anzala, Omu; Sharma, Meenu; Ball, T Blake; Oyugi, Julius; Kiazyk, Sandra

    2015-09-01

    Mycobacterium tuberculosis (Mtb) infects nearly 2 million people annually and is the most common cause of death in HIV-infected individuals. Tuberculosis (TB) diagnostics cater to HIV-uninfected individuals in non-endemic countries, are expensive, slow, and lack sensitivity for those most affected. Patterns of soluble immune markers from Mtb-stimulated immune cells are not well defined in HIV co-infection. We assessed immune differences between HIV-infected and HIV-uninfected individuals with active TB utilizing IFNγ-based QuantiFERON®-TB Gold In-Tube (QFT) testing in Nairobi, Kenya. Excess QFT supernatants were used to measure cytokine and chemokine responses by a 17-plex bead array. Mtb/HIV co-infected participants were significantly less likely to be QFT+ (47.2% versus 84.2% in the HIV-uninfected group), and demonstrated lower expression of all cytokines except for IFNα2. Receiver operator characteristic analyses identified IL-1α as a potential marker of co-infection. Among HIV-infected individuals, CD4+ T cell count correlated weakly with the expression of several analytes. Co-expression analysis highlighted differences in immune profiles between the groups. These data suggest that there is a unique and detectable Mtb-specific immune response in co-infection. A better understanding of Mtb immunology can translate into much needed immunodiagnostics with enhanced sensitivity in HIV-infected individuals, facilitating their opportunity to obtain live-saving treatment.

  12. Increased expression of the inflammatory chemokine CXC chemokine ligand 9/monokine induced by interferon-gamma in lymphoid tissues of rhesus macaques during simian immunodeficiency virus infection and acquired immunodeficiency syndrome.

    PubMed

    Reinhart, Todd A; Fallert, Beth A; Pfeifer, Melanie E; Sanghavi, Sonali; Capuano, Saverio; Rajakumar, Premeela; Murphey-Corb, Michael; Day, Richard; Fuller, Craig L; Schaefer, Todd M

    2002-05-01

    Chemokines are important mediators of cell trafficking during immune inductive and effector activities, and dysregulation of their expression might contribute to the pathogenesis of human immunodeficiency virus type 1 and the related simian immunodeficiency virus (SIV). To understand better the effects of SIV infection on lymphoid tissues in rhesus macaques, we examined chemokine messenger RNA (mRNA) expression patterns by using DNA filter array hybridization. Of the 34 chemokines examined, the interferon gamma (IFN-gamma)-inducible chemokine CXC chemokine ligand 9/monokine induced by interferon-gamma (CXCL9/Mig) was one of the most highly up-regulated chemokines in rhesus macaque spleen tissue early after infection with pathogenic SIV. The relative levels of expression of CXCL9/Mig mRNA in spleen and lymph nodes were significantly increased after infection with SIV in both quantitative image capture and analysis and real-time reverse transcriptase-polymerase chain reaction assays. In addition, in situ hybridization for CXCL9/Mig mRNA revealed that the patterns of expression were altered after SIV infection. Associated with the increased expression of CXCL9/Mig were increased numbers of IFN-gamma mRNA-positive cells in tissues and reduced percentages of CXC chemokine receptor (CXCR) 3(+)/CD3(+) and CXCR3(+)/CD8(+) lymphocytes in peripheral blood. We propose that SIV replication in vivo initiates IFN-gamma-driven positive-feedback loops in lymphoid tissues that disrupt the trafficking of effector T lymphocytes and lead to chronic local inflammation, thereby contributing to immunopathogenesis.

  13. 'Reverse gear' cellular movement mediated by chemokines.

    PubMed

    Zlatopolskiy, A; Laurence, J

    2001-08-01

    We sought to model the mechanism by which leucocytes may be actively repulsed by a beta-chemokine signal. This model is used to interpret an apparent paradox in chemokine biology, whereby high levels of a T-cell chemoattractant, stromal cell derived factor-1 (SDF-1), are present in bone marrow and thymic tissues despite a paucity of mature T lymphocytes in these areas. We postulate the differential involvement in cell migration of the two binding sites on SDF-1 for its sole receptor, CXCR4, depending on whether high or low concentrations of SDF-1 are encountered by the cell. Site choice would be mediated by divergent affinities of the two binding interactions. We also propose differential signalling following SDF-1/CXCR4 interactions on the plasma membrane versus ligand/receptor complexes in endocytic vesicles. Preliminary data showing divergent susceptibility to kinase inhibitors depending on whether a cell is attracted to or repulsed by SDF-1, are consistent with this model. In terms of physical movement toward or away from a chemokine gradient, we compare the cycling of surface receptors during migration to the caterpillar drive of a tractor, which can change direction simply by altering the direction of rotation of its threads. Finally, the potential clinical implications of concentration-dependent, chemokine-based cell attraction and repulsion are discussed. PMID:11488980

  14. Upregulation of chemokine receptor CCR10 is essential for glioma proliferation, invasion and patient survival

    PubMed Central

    Chen, Lingchao; Liu, Xing; Zhang, Hai-Yan; Du, Wenzong; Qin, Zhiyong; Yao, Yu; Mao, Ying; Zhou, Liangfu

    2014-01-01

    Human gliomas are characterized by their invasion of normal brain structures irrespective of their grade of malignancy. Tumor cell invasion share many similarities with leukocyte trafficking, which is critically regulated by chemokines and their receptors. Here we report that the chemokine receptor CCR10 is highly expressed in human glioblastoma compared with control brain tissue. In vitro, signaling through CCL27-CCR10 mediates activation of p-Akt, and subsequently induces proliferation and invasive responses. Cell proliferation and invasion promoted by CCL27 were blocked by inhibition of p-Akt or CCR10. In vivo, down-regulation of CCR10 significantly impairs growth of glioma. Clinically, High CCR10 expression in GBM correlated with p-Akt, shorter overall survival and progression-free survival (P < 0.05). Together, these findings suggest that elevated CCR10 is a critical molecular event associated with gliomagenesis. PMID:25149529

  15. Targeting Rac1 signaling inhibits streptococcal M1 protein-induced CXC chemokine formation, neutrophil infiltration and lung injury.

    PubMed

    Zhang, Songen; Rahman, Milladur; Zhang, Su; Song, Lei; Herwald, Heiko; Thorlacius, Henrik

    2013-01-01

    Infections with Streptococcus pyogenes exhibit a wide spectrum of infections ranging from mild pharyngitis to severe Streptococcal toxic shock syndrome (STSS). The M1 serotype of Streptococcus pyogenes is most commonly associated with STSS. In the present study, we hypothesized that Rac1 signaling might regulate M1 protein-induced lung injury. We studied the effect of a Rac1 inhibitor (NSC23766) on M1 protein-provoked pulmonary injury. Male C57BL/6 mice received NSC23766 prior to M1 protein challenge. Bronchoalveolar fluid and lung tissue were harvested for quantification of neutrophil recruitment, edema and CXC chemokine formation. Neutrophil expression of Mac-1 was quantified by use of flow cytometry. Quantitative RT-PCR was used to determine gene expression of CXC chemokines in alveolar macrophages. Treatment with NSC23766 decreased M1 protein-induced neutrophil infiltration, edema formation and tissue injury in the lung. M1 protein challenge markedly enhanced Mac-1 expression on neutrophils and CXC chemokine levels in the lung. Inhibition of Rac1 activity had no effect on M1 protein-induced expression of Mac-1 on neutrophils. However, Rac1 inhibition markedly decreased M1 protein-evoked formation of CXC chemokines in the lung. Moreover, NSC23766 completely inhibited M1 protein-provoked gene expression of CXC chemokines in alveolar macrophages. We conclude that these novel results suggest that Rac1 signaling is a significant regulator of neutrophil infiltration and CXC chemokine production in the lung. Thus, targeting Rac1 activity might be a potent strategy to attenuate streptococcal M1 protein-triggered acute lung damage.

  16. Sphingosine kinase 1 regulates tumor necrosis factor-mediated RANTES induction through p38 mitogen-activated protein kinase but independently of nuclear factor κB activation.

    PubMed

    Adada, Mohamad M; Orr-Gandy, K Alexa; Snider, Ashley J; Canals, Daniel; Hannun, Yusuf A; Obeid, Lina M; Clarke, Christopher J

    2013-09-20

    Sphingosine kinase 1 (SK1) produces the pro-survival sphingolipid sphingosine 1-phosphate and has been implicated in inflammation, proliferation, and angiogenesis. Recent studies identified TRAF2 as a sphingosine 1-phosphate target, implicating SK1 in activation of the NF-κB pathway, but the functional consequences of this connection on gene expression are unknown. Here, we find that loss of SK1 potentiates induction of the chemokine RANTES (regulated on activation, normal T cell expressed and secreted; also known as CCL5) in HeLa cells stimulated with TNF-α despite RANTES induction being highly dependent on the NF-κB pathway. Additionally, we find that SK1 is not required for TNF-induced IKK phosphorylation, IκB degradation, nuclear translocation of NF-κB subunits, and transcriptional NF-κB activity. In contrast, loss of SK1 prevented TNF-induced phosphorylation of p38 MAPK, and inhibition of p38 MAPK, like SK1 knockdown, also potentiates RANTES induction. Finally, in addition to RANTES, loss of SK1 also potentiated the induction of multiple chemokines and cytokines in the TNF response. Taken together, these data identify a potential and novel anti-inflammatory function of SK1 in which chemokine levels are suppressed through SK1-mediated activation of p38 MAPK. Furthermore, in this system, activation of NF-κB is dissociated from SK1, suggesting that the interaction between these pathways may be more complex than currently thought.

  17. Altered responsiveness to chemokines due to targeted disruption of SHIP

    PubMed Central

    Kim, Chang H.; Hangoc, Giao; Cooper, Scott; Helgason, Cheryl D.; Yew, Sandie; Humphries, R. Keith; Krystal, Gerald; Broxmeyer, Hal E.

    1999-01-01

    SHIP has been implicated in negative signaling in a number of hematopoietic cell types and is postulated to downregulate phosphatidylinositol-3-kinase– (PI-3K–) initiated events in diverse receptor signaling pathways. Because PI-3K is implicated in chemokine signaling, we investigated whether SHIP plays any role in cellular responses to chemokines. We found that a number of immature and mature hematopoietic cells from SHIP-deficient mice manifested enhanced directional migration (chemotaxis) in response to the chemokines stromal cell–derived factor-1 (SDF-1) and B-lymphocyte chemoattractant (BLC). SHIP–/– cells were also more active in calcium influx and actin polymerization in response to SDF-1. However, colony formation by SHIP-deficient hematopoietic progenitor cell (HPCs) was not inhibited by 13 myelosuppressive chemokines that normally inhibit proliferation of HPCs. These altered biologic activities of chemokines on SHIP-deficient cells are not caused by simple modulation of chemokine receptor expression in SHIP-deficient mice, implicating SHIP in the modulation of chemokine-induced signaling and downstream effects. J. Clin. Invest. 104:1751–1759 (1999). PMID:10606629

  18. Chemokine and Chemokine Receptor Polymorphisms in Bipolar Disorder

    PubMed Central

    Tokac, Damla; Tuzun, Erdem; Gulec, Huseyin; Yılmaz, Vuslat; Bireller, Elif Sinem; Cakmakoglu, Bedia

    2016-01-01

    Objective Bipolar disorder (BD) is a debilitating psychiatric disease with unknown etiology. Recent studies have shown inflammation as a potential contributing factor of BD pathogenesis. However, potential associations between chemokine and chemokine receptor polymorphisms and BD have been fundamentally understudied. To identify participation of chemokines in BD pathogenesis, we examined genetic variants of several chemokine and chemokine receptor genes. Methods The study population comprised 200 patients with BD and 195 age- and sex-matched healthy controls. Genotyping of monocyte chemotactic protein 1 (MCP-1) A2518G, CCR2 V64I, CCR5 Δ32, CCR5 A55029G, stromal cell-derived factor 1 (SDF-1) 3'A, and CXCR4 C138T polymorphisms was performed using polymerase chain reaction and restriction enzyme digestion. Results We found that CCR5-Δ32 II and CXCR4-C138T C+ genotype frequencies contributed to an increased risk for BD. However, no statistical significance could be obtained with these genotypes after Bonferroni correction. A significant asssociation was only found with MCP-1 GG and G+ genotypes, which were markedly more prevalent in patients with BD and these genotypes seemed to significantly increase the risk for BD even after Bonferroni correction. Conclusion Our findings indicate an association between genetic variants of certain chemokine and chemokine receptor (especially MCP-1) genes and BD. The exact mechanisms by which these variants contribute to BD pathogenesis and their clinical implications need to be further investigated. PMID:27757133

  19. Monocyte-Induced Prostate Cancer Cell Invasion is Mediated by Chemokine ligand 2 and Nuclear Factor-κB Activity

    PubMed Central

    Lindholm, Paul F; Sivapurapu, Neela; Jovanovic, Borko; Kajdacsy-Balla, André

    2015-01-01

    Study Background The tumor microenvironment contains inflammatory cells which can influence cancer growth and progression; however the mediators of these effects vary with different cancer types. The mechanisms by which prostate cancer cells communicate with monocytes to promote cancer progression are incompletely understood. This study tested prostate cancer cell and monocyte interactions that lead to increased prostate cancer cell invasion. Methods We analyzed the prostate cancer cell invasion and NF-κB activity and cytokine expression during interaction with monocyte-lineage cells in co-cultures. The roles of monocyte chemotactic factor (MCP-1/CCL2) and NF-κB activity for co-culture induced prostate cancer invasion were tested. Clinical prostate cancer NF-κB expression was analyzed by immunohistochemistry. Results In co-cultures of prostate cancer cell lines with monocyte-lineage cells, (C-C motif) ligand 2 (CCL2) levels were significantly increased when compared with monocytes or cancer cells cultured alone. Prostate cancer cell invasion was induced by recombinant CCL2 in a dose dependent manner, similar to co-cultures with monocytes. The monocyte-induced prostate cancer cell invasion was inhibited by CCL2 neutralizing antibodies and by the CCR2 inhibitor, RS102895. Prostate cancer cell invasion and CCL2 expression induced in the co-cultures was inhibited by Lactacystin and Bay11-7082 NF-κB inhibitors. Prostate cancer cell NF-κB DNA binding activity depended on CCL2 dose and was inhibited by CCL2 neutralizing antibodies. Clinical prostate cancer NF-κB expression correlated with tumor grade. Conclusions Co-cultures with monocyte-lineage cell lines stimulated increased prostate cancer cell invasion through increased CCL2 expression and increased prostate cancer cell NF-κB activity. CCL2 and NF-κB may be useful therapeutic targets to interfere with inflammation-induced prostate cancer invasion. PMID:26317041

  20. Suppressive effects of Bifidobacterium longum on the production of Th2-attracting chemokines induced with T cell-antigen-presenting cell interactions.

    PubMed

    Iwabuchi, Noriyuki; Takahashi, Noritoshi; Xiao, Jin-Zhong; Yonezawa, Sumiko; Yaeshima, Tomoko; Iwatsuki, Keiji; Hachimura, Satoshi

    2009-04-01

    In human trials, Bifidobacterium longum BB536 alleviates subjective symptoms of Japanese cedar pollinosis, an IgE-mediated type I allergy caused by exposure to Japanese cedar, and significantly suppresses the increase of plasma thymus- and activation-regulated chemokine (TARC) associated with pollen dispersion. In the present study, we investigated the suppressive effects of BB536 on the production of T helper type 2 (Th2)-attracting chemokines, such as TARC and macrophage-derived chemokine (MDC), together with the mechanisms of their production. Murine splenocytes were cultured with heat-killed BB536, and the levels of Th2-attracting chemokines in the supernatants were measured. TARC and MDC were produced in cultures without stimulation, and the production was significantly suppressed by BB536. These chemokines were produced by antigen-presenting cells (APCs) of splenocytes stimulated with an anti-CD40 antibody. Furthermore, TARC production was induced with granulocyte macrophage colony-stimulating factor that was produced by T cells and dendritic cells. BB536 suppressed MDC production induced with the anti-CD40 antibody by APCs from the spleen, mesenteric lymph nodes (MLNs) and Peyer's patches, and it suppressed TARC production by APCs from the spleen and MLNs. These results indicate that BB536 suppresses the production of Th2-attracting chemokines induced by the T cell-APC interaction, suggesting a novel mechanism for alleviating symptoms of allergic disorders by probiotics.

  1. Methemoglobin-induced signaling and chemokine responses in human alveolar epithelial cells

    PubMed Central

    Mumby, Sharon; Ramakrishnan, Latha; Evans, Timothy W.; Griffiths, Mark J. D.

    2013-01-01

    Diffuse alveolar hemorrhage is characterized by the presence of red blood cells and free hemoglobin in the alveoli and complicates a number of serious medical and surgical lung conditions including the pulmonary vasculitides and acute respiratory distress syndrome. In this study we investigated the hypothesis that exposure of human alveolar epithelial cells to hemoglobin and its breakdown products regulates chemokine release via iron- and oxidant-mediated activation of the transcription factor NF-κB. Methemoglobin alone stimulated the release of IL-8 and MCP-1 from A549 cells via activation of the NF-κB pathway; additionally, IL-8 required ERK activation and MCP-1 required JNK activation. Neither antioxidants nor iron chelators and knockdown of ferritin heavy and light chains affected these responses, indicating that iron and reactive oxygen species are not involved in the response of alveolar epithelial cells to methemoglobin. Incubation of primary cultures of human alveolar type 2 cells with methemoglobin resulted in a similar pattern of chemokine release and signaling pathway activation. In summary, we have shown for the first time that methemoglobin induced chemokine release from human lung epithelial cells independent of iron- and redox-mediated signaling involving the activation of the NF-κB and MAPK pathways. Decompartmentalization of hemoglobin may be a significant proinflammatory stimulus in a variety of lung diseases. PMID:24142518

  2. Dual-Color Luciferase Complementation for Chemokine Receptor Signaling.

    PubMed

    Luker, Kathryn E; Luker, Gary D

    2016-01-01

    Chemokine receptors may share common ligands, setting up potential competition for ligand binding, and association of activated receptors with downstream signaling molecules such as β-arrestin. Determining the "winner" of competition for shared effector molecules is essential for understanding integrated functions of chemokine receptor signaling in normal physiology, disease, and response to therapy. We describe a dual-color click beetle luciferase complementation assay for cell-based analysis of interactions of two different chemokine receptors, CXCR4 and ACKR3, with the intracellular scaffolding protein β-arrestin 2. This assay provides real-time quantification of receptor activation and signaling in response to chemokine CXCL12. More broadly, this general imaging strategy can be applied to quantify interactions of any set of two proteins that interact with a common binding partner.

  3. Effect of interleukin-17 on the expression of chemokines in gingival epithelial cells.

    PubMed

    Takahashi, Naoki; Okui, Takafumi; Tabeta, Koichi; Yamazaki, Kazuhisa

    2011-10-01

    The role of interleukin (IL)-17 in cellular communication in inflammation has been well described, and a positive correlation between the severity of periodontitis and the level of IL-17 was reported. Although epithelial cells are a major target of IL-17, little is known about the effect of IL-17 on the production of chemokines by human gingival epithelial cells (HGECs). We evaluated the effects of IL-17 on the expression of CXCL8 and CCL2 by HGECs using quantitative real-time PCR and ELISA. In addition, the role of the nuclear factor (NF)-κB signalling pathway in the IL-17-mediated expression of chemokines was assessed using a specific inhibitor. Stimulation with IL-17 up-regulated the expression of CXCL8 mRNA but not of CCL2 mRNA in HGECs, whereas tumour necrosis factor-α (TNF-α) elevated the expression of mRNA for both chemokines. Stimulation with IL-17 up-regulated the secretion of CXCL8 protein, but not the secretion of CCL2 protein. The effect of IL-17 on CXCL8 production was suppressed using an anti-IL-17R Ig, suggesting a role for a specific receptor-ligand interaction. Inhibition of the NF-κB signalling pathway demonstrated that NF-κB activation is required for the CXCL8 expression in HGECs. In conclusion, IL-17 is involved in the regulation of the innate immune response in HGECs by inducing CXCL8 production.

  4. The effect of HIV coinfection, HAART and TB treatment on cytokine/chemokine responses to Mycobacterium tuberculosis (Mtb) antigens in active TB patients and latently Mtb infected individuals.

    PubMed

    Kassa, Desta; de Jager, Wilco; Gebremichael, Gebremedhin; Alemayehu, Yodit; Ran, Leonie; Fransen, Justin; Wolday, Dawit; Messele, Tsehaynesh; Tegbaru, Belete; Ottenhoff, Tom H M; van Baarle, Debbie

    2016-01-01

    Identification of Mtb specific induced cytokine/chemokine host biomarkers could assist in developing novel diagnostic, prognostic and therapeutic tools for TB. Levels of IFN-γ, IL-2, IL-17, IL-10, IP-10 and MIP-1α were measured in supernatants of whole blood stimulated with Mtb specific fusion protein ESAT-6/CFP-10 using xMAP technology. The study groups were HIV positive TB patients (HIV(+)TB(+)), HIV negative TB patients (HIV(-)TB(+)), HIV positive tuberculin skin test positive (TST+) (HIV(+)TST(+)), HIV negative TST+ (HIV(-)TST(+)), and HIV(-)TST(-) individuals. Compared to HIV(-)TST(-), latent TB infection led to increased levels of IP-10, IFN-γ and IL-17, while levels of IL-2 and IP-10 were increased with active TB. Levels of IFN-γ, IL-17, MIP-1α, and IL-10 were increased in HIV(-)TST(+) individuals compared to HIV(-)TB(+) patients. HIV coinfection decreased the level of IFN-γ, IL-17, IP-10 and IL-2. After six months (M6) of anti-TB treatment (ATT) in HIV(-)TB(+) patients, IFN-γ, IL-10, and MIP-1α levels normalized. After M6 and M18 of ATT plus HAART in HIV(+)TB(+) patients, levels of MIP-1α and IL-10 normalized, while this was not the case for IFN-γ, IL-2, IL-17, and IP-10 levels. In HIV(+)TST(+) patients on HAART, levels of IFN-γ, IL-17, IL-10 and MIP-1α normalized, while no change in the levels of IL-2 and IP-10 were observed. In conclusion, the simultaneous measurement of IFN-γ, IL-17 and IP-10 may assist in diagnosing LTBI; IL-2 and IP-10 may assist in diagnosing active TB; while IFN-γ, IL-17, MIP-1α, and IL-10 levels could help to discriminate LTBI and active TB. In addition, IL-10 and MIP-1α levels could help to monitor responses to TB treatment and HAART.

  5. Emerging Concepts and Approaches for Chemokine-Receptor Drug Discovery

    PubMed Central

    O’Hayre, Morgan; Salanga, Catherina L.; Handel, Tracy M.; Hamel, Damon J.

    2010-01-01

    Importance of the field Chemokine receptors are G protein-coupled receptors (GPCRs) most noted for their role in cell migration. However, inappropriate utilization or regulation of these receptors is implicated in many inflammatory diseases, cancer and HIV, making them important drug targets. Areas covered in this review Allostery, oligomerization, and ligand bias are presented as they pertain to chemokine receptors and their associated pathologies. Specific examples of each are described from the recent literature and their implications are discussed in terms of drug discovery efforts targeting chemokine receptors. What the reader will gain Insight into the expanding view of the multitude of pharmacological variables that need to be considered or that may be exploited in chemokine receptor drug discovery. Take home message Since 2007, two drugs targeting chemokine receptors have been approved by the FDA, Maraviroc for preventing HIV infection and Mozobil™ for hematopoietic stem cell mobilization. While these successes permit optimism for chemokine receptors as drug targets, only recently has the complexity of this system begun to be appreciated. The concepts of allosteric inhibitors, biased ligands and functional selectivity raise the possibility that drugs with precisely-defined properties can be developed. Other complexities such as receptor oligomerization and tissue-specific functional states of receptors also offer opportunities for increased target and response specificity, although it will be more challenging to translate these ideas into approved therapeutics compared to traditional approaches. PMID:21132095

  6. The chemokine CCL2 increases Nav1.8 sodium channel activity in primary sensory neurons through a Gβγ-dependent mechanism.

    PubMed

    Belkouch, Mounir; Dansereau, Marc-André; Réaux-Le Goazigo, Annabelle; Van Steenwinckel, Juliette; Beaudet, Nicolas; Chraibi, Ahmed; Melik-Parsadaniantz, Stéphane; Sarret, Philippe

    2011-12-14

    Changes in function of voltage-gated sodium channels in nociceptive primary sensory neurons participate in the development of peripheral hyperexcitability that occurs in neuropathic and inflammatory chronic pain conditions. Among them, the tetrodotoxin-resistant (TTX-R) sodium channel Na(v)1.8, primarily expressed by small- and medium-sized dorsal root ganglion (DRG) neurons, substantially contributes to the upstroke of action potential in these neurons. Compelling evidence also revealed that the chemokine CCL2 plays a critical role in chronic pain facilitation via its binding to CCR2 receptors. In this study, we therefore investigated the effects of CCL2 on the density and kinetic properties of TTX-R Na(v)1.8 currents in acutely small/medium dissociated lumbar DRG neurons from naive adult rats. Whole-cell patch-clamp recordings demonstrated that CCL2 concentration-dependently increased TTX-resistant Na(v)1.8 current densities in both small- and medium-diameter sensory neurons. Incubation with CCL2 also shifted the activation and steady-state inactivation curves of Na(v)1.8 in a hyperpolarizing direction in small sensory neurons. No change in the activation and inactivation kinetics was, however, observed in medium-sized nociceptive neurons. Our electrophysiological recordings also demonstrated that the selective CCR2 antagonist INCB3344 [N-[2-[[(3S,4S)-1-E4-(1,3-benzodioxol-5-yl)-4-hydroxycyclohexyl]-4-ethoxy-3-pyrrolidinyl]amino]-2-oxoethyl]-3-(trifluoromethyl)benzamide] blocks the potentiation of Na(v)1.8 currents by CCL2 in a concentration-dependent manner. Furthermore, the enhancement in Na(v)1.8 currents was prevented by pretreatment with pertussis toxin (PTX) or gallein (a Gβγ inhibitor), indicating the involvement of Gβγ released from PTX-sensitive G(i/o)-proteins in the cross talk between CCR2 and Na(v)1.8. Together, our data clearly demonstrate that CCL2 may excite primary sensory neurons by acting on the biophysical properties of Na(v)1.8 currents

  7. The chemokine system in experimental and clinical hematology.

    PubMed

    Bruserud, Øystein; Kittang, Astrid Olsnes

    2010-01-01

    The chemokine family consists of approximately 50 small (8-14 kDa), basic proteins that are expressed and released by a wide range of normal and malignant cells. Based on their molecular structure, these cytokines are divided into the two major subgroups CCL and CXCL chemokines that bind to CCR or CXCR receptors, respectively. These mediators are important for regulation of cell viability, proliferation, differentiation, and migration. Chemokines are important for cell migration during embryogenesis; they are involved in the regulation of complex processes like local recruitment of inflammatory cells, angiogenesis, and regulation of normal as well as leukemic hematopoiesis. Chemokines can be constitutively released by malignant hematopoietic cells as well as by bone marrow stromal cells. This bidirectional crosstalk between malignant hematopoietic cells and neighboring stromal cells may therefore be important for the development and clinical presentation of malignant diseases, and the chemokines or their receptors may also represent a target for specific anticancer therapy at the molecular level. PMID:20369318

  8. The Human Cutaneous Chemokine System

    PubMed Central

    McCully, Michelle L.; Moser, Bernhard

    2011-01-01

    Irrespective of the immune status, the vast majority of all lymphocytes reside in peripheral tissues whereas those present in blood only amount to a small fraction of the total. It has been estimated that T cells in healthy human skin outnumber those present in blood by at least a factor of two. How lymphocytes within these two compartments relate to each other is not well understood. However, mounting evidence suggest that the study of T cell subsets present in peripheral blood does not reflect the function of their counterparts at peripheral sites. This is especially true under steady-state conditions whereby long-lived memory T cells in healthy tissues, notably those in epithelial tissues at body surfaces, are thought to fulfill a critical immune surveillance function by contributing to the first line of defense against a series of local threats, including microbes, tumors, and toxins, and by participating in wound healing. The relative scarcity of information regarding peripheral T cells and the factors regulating their localization is primarily due to inherent difficulties in obtaining healthy tissue for the extraction and study of immune cells on a routine basis. This is most certainly true for humans. Here, we review our current understanding of T cell homing to human skin and compare it when possible with gut-selective homing. We also discuss candidate chemokines that may account for the tissue selectivity in this process and present a model whereby CCR8, and its ligand CCL1, selectively regulate the homeostatic migration of memory lymphocytes to skin tissue. PMID:22566823

  9. Therapeutic implications of chemokine-mediated pathways in atherosclerosis: realistic perspectives and utopias.

    PubMed

    Apostolakis, Stavros; Amanatidou, Virginia; Spandidos, Demetrios A

    2010-09-01

    Current perspectives on the pathogenesis of atherosclerosis strongly support the involvement of inflammatory mediators in the establishment and progression of atherosclerostic lesions. Chemokine-mediated mechanisms are potent regulators of such processes by orchestrating the interactions of inflammatory cellular components of the peripheral blood with cellular components of the arterial wall. The increasing evidence supporting the role of chemokine pathways in atherosclerosis renders chemokine ligands and their receptors potential therapeutic targets. In the following review, we aim to highlight the special structural and functional features of chemokines and their receptors in respect to their roles in atherosclerosis, and examine to what extent available data can be applied in disease management practices.

  10. The histone deacetylase inhibitor suberoylanilide hydroxamic acid induces apoptosis, down-regulates the CXCR4 chemokine receptor and impairs migration of chronic lymphocytic leukemia cells

    PubMed Central

    Stamatopoulos, Basile; Meuleman, Nathalie; De Bruyn, Cécile; Delforge, Alain; Bron, Dominique; Lagneaux, Laurence

    2010-01-01

    Background Chronic lymphocytic leukemia is a neoplastic disorder that arises largely as a result of defective apoptosis leading to chemoresistance. Stromal cell-derived factor-1 and its receptor, CXCR4, have been shown to play an important role in chronic lymphocytic leukemia cell trafficking and survival. Design and Methods Since histone acetylation is involved in the modulation of gene expression, we evaluated the effects of suberoylanilide hydroxamic acid, a histone deacetylase inhibitor, on chronic lymphocytic leukemia cells and in particular on cell survival, CXCR4 expression, migration, and drug sensitization. Results Here, we showed that treatment with suberoylanilide hydroxamic acid (20 μM) for 48 hours induced a decrease in chronic lymphocytic leukemia cell viability via apoptosis (n=20, P=0.0032). Using specific caspase inhibitors, we demonstrated the participation of caspases-3, -6 and -8, suggesting an activation of the extrinsic pathway. Additionally, suberoylanilide hydroxamic acid significantly decreased CXCR4 mRNA (n=10, P=0.0010) and protein expression (n=40, P<0.0001). As a result, chronic lymphocytic leukemia cell migration in response to stromal cell-derived factor-1 (n=23, P<0.0001) or through bone marrow stromal cells was dramatically impaired. Consequently, suberoylanilide hydroxamic acid reduced the protective effect of the microenvironment and thus sensitized chronic lymphocytic leukemia cells to chemotherapy such as fludarabine. Conclusions In conclusion, suberoylanilide hydroxamic acid induces apoptosis in chronic lymphocytic leukemia cells via the extrinsic pathway and down-regulates CXCR4 expression leading to decreased cell migration. Suberoylanilide hydroxamic acid in combination with other drugs represents a promising therapeutic approach to inhibiting migration, chronic lymphocytic leukemia cell survival and potentially overcoming drug resistance. PMID:20145270

  11. Long non-coding RNA-GAS5 acts as a tumor suppressor in bladder transitional cell carcinoma via regulation of chemokine (C-C motif) ligand 1 expression

    PubMed Central

    CAO, QIFENG; WANG, NING; QI, JUAN; GU, ZHENGQIN; SHEN, HAIBO

    2016-01-01

    Long non-coding RNAs (lncRNAs) have important roles in diverse biological processes, including transcriptional regulation, cell growth and tumorigenesis. The present study aimed to investigate whether lncRNA-growth arrest-specific (GAS)5 regulated bladder cancer progression via regulation of chemokine (C-C) ligand (CCL)1 expression. The viability of BLX bladder cancer cells was detected using a Cell Counting kit-8 assay, and cell apoptosis was assessed by annexin V-propidium iodide double-staining. The expression levels of specific genes and proteins were analyzed by reverse transcription-quantitative polymerase chain reaction and western blotting, respectively. In addition, cells were transfected with small interfering (si)RNAs or recombinant GAS5 in order to silence or overexpress GAS5, respectively. The results of the present study demonstrated that knockdown of GAS5 expression promoted bladder cancer cell proliferation, whereas overexpression of GAS5 suppressed cell proliferation. Furthermore, knockdown of GAS5 resulted in an increased percentage of cells in S and G2 phase, and a decreased percentage of cells in G1 phase. In addition, the present study performed a hierarchical cluster analysis of differentially expressed lncRNAs in bladder cancer cells and detected that CCL1 overexpression resulted in an upregulation of GAS5, which may improve the ability of cells to regulate a stress response in vitro. Furthermore, knockdown of GAS5 expression increased the mRNA and protein expression of CCL1 in bladder cancer cells. Gain-of-function and loss-of-function studies demonstrated that GAS5 was able to inhibit bladder cancer cell proliferation, at least in part, by suppressing the expression of CCL1. The results of the present study demonstrated that GAS5 was able to suppress bladder cancer cell proliferation, at least partially, by suppressing the expression of CCL1. The results of the present study may provide a basis for developing novel effective treatment

  12. (+)-Nootkatone inhibits tumor necrosis factor α/interferon γ-induced production of chemokines in HaCaT cells.

    PubMed

    Choi, Hyeon-Jae; Lee, Jin-Hwee; Jung, Yi-Sook

    2014-05-01

    Chemokines are important mediators of cell migration, and thymus and activation-regulated chemokine (TARC/CCL17) and macrophage-derived chemokine (MDC/CCL22) are well-known typical inflammatory chemokines involved in atopic dermatitis (AD). (+)-Nootkatone is the major component of Cyperus rotundus. (+)-Nootkatone has antiallergic, anti-inflammatory, and antiplatelet activities. The purpose of this study was to investigate the effect of (+)-nootkatone on tumor necrosis factor α (TNF-α)/interferon γ (IFN-γ)-induced expression of Th2 chemokines in HaCaT cells. We found that (+)-nootkatone inhibited the TNF-α/IFN-γ-induced expression of TARC/CCL17 and MDC/CCL22 mRNA in HaCaT cells. It also significantly inhibited TNF-α/IFN-γ-induced activation of nuclear factor kappa B (NF-κB), p38 mitogen-activated protein kinase (MAPK), and protein kinase Cζ (PKCζ). Furthermore, we showed that PKCζ and p38 MAPK contributed to the inhibition of TNF-α/IFN-γ-induced TARC/CCL17 and MDC/CCL22 expression by blocking IκBα degradation in HaCaT cells. Taken together, these results suggest that (+)-nootkatone may suppress TNF-α/IFN-γ-induced TARC/CCL17 and MDC/CCL22 expression in HaCaT cells by inhibiting of PKCζ and p38 MAPK signaling pathways that lead to activation of NF-κB. We propose that (+)-nootkatone may be a useful therapeutic candidate for inflammatory skin diseases such as AD. PMID:24704449

  13. Transmembrane chemokines act as receptors in a novel mechanism termed inverse signaling

    PubMed Central

    Hattermann, Kirsten; Gebhardt, Henrike; Krossa, Sebastian; Ludwig, Andreas; Lucius, Ralph

    2016-01-01

    The transmembrane chemokines CX3CL1/fractalkine and CXCL16 are widely expressed in different types of tumors, often without an appropriate expression of their classical receptors. We observed that receptor-negative cancer cells could be stimulated by the soluble chemokines. Searching for alternative receptors we detected that all cells expressing or transfected with transmembrane chemokine ligands bound the soluble chemokines with high affinity and responded by phosphorylation of intracellular kinases, enhanced proliferation and anti-apoptosis. This activity requires the intracellular domain and apparently the dimerization of the transmembrane chemokine ligand. Thus, shed soluble chemokines can generate auto- or paracrine signals by binding and activating their transmembrane forms. We term this novel mechanism “inverse signaling”. We suppose that inverse signaling is an autocrine feedback and fine-tuning system in the communication between cells that in tumors supports stabilization and proliferation. DOI: http://dx.doi.org/10.7554/eLife.10820.001 PMID:26796342

  14. Single-Cell Analysis of Mast Cell Degranulation Induced by Airway Smooth Muscle-Secreted Chemokines

    PubMed Central

    Manning, Benjamin M.; Meyer, Audrey F.; Gruba, Sarah M.; Haynes, Christy L.

    2015-01-01

    Background Asthma is a chronic inflammatory disease characterized by narrowed airways, bronchial hyper-responsiveness, mucus hyper-secretion, and airway remodeling. Mast cell (MC) infiltration into airway smooth muscle (ASM) is a defining feature of asthma, and ASM regulates the inflammatory response by secreting chemokines, including CXCL10 and CCL5. Single cell analysis offers a unique approach to study specific cellular signaling interactions within large and complex signaling networks such as the inflammatory microenvironment in asthma. Methods Carbon fiber microelectrode amperometry was used to study the effects of ASM–secreted chemokines on mouse peritoneal MC degranulation. Results MC degranulation in response to CXCL10 and CCL5 was monitored at the single cell level. Relative to IgE-mediated degranulation, CXCL10- and CCL5-stimulated MCs released a decreased amount of serotonin per granule with fewer release events per cell. Decreased serotonin released per granule was correlated with increased spike half-width and rise-time values. Conclusions MCs are directly activated with ASM-associated chemokines. CXCL10 and CCL5 induce less robust MC degranulation compared to IgE- and A23187-stimulation. The kinetics of MC degranulation are signaling pathway-dependent, suggesting a biophysical mechanism of regulated degranulation that incorporates control over granule trafficking, transport, and docking machinery. General Significance The biophysical mechanisms, including variations in number of exocytotic release events, serotonin released per granule, and the membrane kinetics of exocytosis that underlie MC degranulation in response to CXCL10 and CCL5 were characterized at the single cell level. These findings clarify the function of ASM-derived chemokines as instigators of MC degranulation relative to classical mechanisms of MC stimulation. PMID:25986989

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

    PubMed Central

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

    2016-01-01

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

  16. Induction of interleukin-8 by Naegleria fowleri lysates requires activation of extracellular signal-regulated kinase in human astroglial cells.

    PubMed

    Kim, Jong-Hyun; Sohn, Hae-Jin; Lee, Sang-Hee; Kwon, Daeho; Shin, Ho-Joon

    2012-08-01

    Naegleria fowleri is a pathogenic free-living amoeba which causes primary amoebic meningoencephalitis in humans and experimental animals. To investigate the mechanisms of such inflammatory diseases, potential chemokine gene activation in human astroglial cells was investigated following treatment with N. fowleri lysates. We demonstrated that N. fowleri are potent inducers for the expression of interleukin-8 (IL-8) genes in human astroglial cells which was preceded by activation of extracellular signal-regulated kinase (ERK). In addition, N. fowleri lysates induces the DNA binding activity of activator protein-1 (AP-1), an important transcription factor for IL-8 induction. The specific mitogen-activated protein kinase kinase/ERK inhibitor, U0126, blocks N. fowleri-mediated AP-1 activation and subsequent IL-8 induction. N. fowleri-induced IL-8 expression requires activation of ERK in human astroglial cells. These findings indicate that treatment of N. fowleri on human astroglial cells leads to the activation of AP-1 and subsequent expression of IL-8 which are dependent on ERK activation. These results may help understand the N. fowleri-mediated upregulation of chemokine and cytokine expression in the astroglial cells.

  17. Kinetic mRNA Profiling in a Rat Model of Left-Ventricular Hypertrophy Reveals Early Expression of Chemokines and Their Receptors

    PubMed Central

    Nemska, Simona; Monassier, Laurent; Gassmann, Max; Frossard, Nelly; Tavakoli, Reza

    2016-01-01

    Left-ventricular hypertrophy (LVH), a risk factor for heart failure and death, is characterized by cardiomyocyte hypertrophy, interstitial cell proliferation, and leukocyte infiltration. Chemokines interacting with G protein-coupled chemokine receptors may play a role in LVH development by promoting recruitment of activated leukocytes or modulating left-ventricular remodeling. Using a pressure overload-induced kinetic model of LVH in rats, we examined during 14 days the expression over time of chemokine and chemokine receptor mRNAs in left ventricles from aortic-banded vs sham-operated animals. Two phases were clearly distinguished: an inflammatory phase (D3-D5) with overexpression of inflammatory genes such as il-1ß, tnfa, nlrp3, and the rela subunit of nf-kb, and a hypertrophic phase (D7-D14) where anp overexpression was accompanied by a heart weight/body weight ratio that increased by more than 20% at D14. No cardiac dysfunction was detectable by echocardiography at the latter time point. Of the 36 chemokines and 20 chemokine receptors analyzed by a Taqman Low Density Array panel, we identified at D3 (the early inflammatory phase) overexpression of mRNAs for the monocyte chemotactic proteins CCL2 (12-fold increase), CCL7 (7-fold increase), and CCL12 (3-fold increase), for the macrophage inflammatory proteins CCL3 (4-fold increase), CCL4 (2-fold increase), and CCL9 (2-fold increase), for their receptors CCR2 (4-fold increase), CCR1 (3-fold increase), and CCR5 (3-fold increase), and for CXCL1 (8-fold increase) and CXCL16 (2-fold increase). During the hypertrophic phase mRNA expression of chemokines and receptors returned to the baseline levels observed at D0. Hence, this first exhaustive study of chemokine and chemokine receptor mRNA expression kinetics reports early expression of monocyte/macrophage-related chemokines and their receptors during the development of LVH in rats, followed by regulation of inflammation as LVH progresses. PMID:27525724

  18. Gene profile of chemokines on hepatic stellate cells of schistosome-infected mice and antifibrotic roles of CXCL9/10 on liver non-parenchymal cells.

    PubMed

    Liang, Yue-jin; Luo, Jie; Lu, Qiao; Zhou, Ying; Wu, Hai-wei; Zheng, Dan; Ren, Yong-ya; Sun, Ke-yi; Wang, Yong; Zhang, Zhao-song

    2012-01-01

    Hepatic stellate cells (HSCs) play a key role in the development of liver fibrosis caused by schistosomiasis. Chemokines were widely expressed and involved in cellular activation, proliferation and migration in inflammatory and infectious diseases. However, little is known about the expressions of chemokines on HSCs in the schistosoma infection. In addition, the roles of chemokines in pathogenesis of liver fibrosis are not totally clear. In our study, we used microarray to analyze the temporal gene expressions of primary HSCs isolated from mice with both acute and chronic schistosomiasis. Our microarray data showed that most of the chemokines expressed on HSCs were upregulated at 3 weeks post-infection (p.i) when the egg granulomatous response was not obviously evoked in the liver. However, some of them like CXCL9, CXCL10 and CXCL11 were subsequently decreased at 6 weeks p.i when the granulomatous response reached the peak. In the chronic stage, most of the differentially expressed chemokines maintained persistent high-abundances. Furthermore, several chemokines including CCR2, CCR5, CCR7, CXCR3, CXCR4, CCL2, CCL5, CCL21, CXCL9 and CXCL10 were expressed by HCSs and the abundances of them were changed following the praziquantel treatment in the chronic stage, indicating that chemokines were possibly necessary for the persistence of the chronic stage. In vitro experiments, hepatic non-parenchymal cells, primary HSCs and human HSCs line LX-2 were stimulated by chemokines. The results showed that CXCL9 and CXCL10, but not CXCL11 or CXCL4, significantly inhibited the gene expressions of Col1α1, Col3α1 and α-SMA, indicating the potential anti-fibrosis effect of CXCL9 and CXCL10 in schistosomiasis. More interestingly, soluble egg antigen (SEA) of Schistosoma japonicum was able to inhibit transcriptional expressions of some chemokines by LX-2 cells, suggesting that SEA was capable of regulating the expression pattern of chemokine family and modulating the hepatic immune

  19. Selected CC and CXC chemokines in children with atopic asthma

    PubMed Central

    Machura, Edyta; Mazur, Bogdan; Chrobak, Ewelina; Ziora, Katarzyna; Ziora, Dariusz; Kasperska-Zajac, Alicja

    2016-01-01

    Introduction There are only limited data on CC and CXC chemokines regulation in children with asthma. Aim We compared the serum profile of selected CC and CXC chemokines in patients with atopic asthma and healthy children. Material and methods Serum concentration of CC chemokines RANTES, MCP-1, and CXC chemokines IP-10, MIG, IL-8, RANTES was measured using cytometric bead array in 44 children with atopic asthma and 17 healthy subjects. Results The concentration of RANTES was significantly higher and the MIG level was lower in all children with asthma as compared to their control counterparts. We observed increased RANTES and decreased MIG levels also in patients with stable asthma when compared with children in the control group. The IP-10 concentration was similar between the whole asthma group and healthy controls, while significantly increased levels of this chemokine in acute asthma have been observed when compared to stable asthma. For MCP-1 and IL-8, the serum concentration was similar in all compared groups. The MIG concentration correlated positively with IP-10, IL-8, and CRP levels and negatively with the eosinophil count. A negative correlation between the IP-10 and eosinophil count and a negative correlation between FEV1 and IP-10 were found. Conclusions An increased serum RANTES level in children with asthma may result in enhancement of Th2 lymphocyte recruitment into the airway. A decreased expression of Th1 chemokine MIG in children with stable asthma may contribute to a diminished antagonizing effect on Th2 cytokine production and hence intensify Th2 predominance. An increased IP-10 level in children during an asthma attack suggest that this chemokine is a serological marker of disease exacerbation. PMID:27279817

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

    PubMed

    Onoprienko, L V

    2011-01-01

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

  1. Serum concentration of macrophage-derived chemokine may be a useful inflammatory marker for assessing severity of atopic dermatitis in infants and young children.

    PubMed

    Leung, Ting Fan; Ma, Kwok Chiu; Hon, Kam Lun; Lam, Christopher W K; Wan, Helene; Li, Chung Yi; Chan, Iris H S

    2003-08-01

    Chemokines are responsible for the trafficking of leukocytes to sites of inflammation. Serum chemokine levels were previously shown to be increased in adult patients with atopic dermatitis (AD). We tested whether serum concentrations of chemokines, including macrophage-derived chemokine (MDC), thymus and activation-regulated chemokine (TARC), eotaxin (EOX), interferon gamma inducible protein 10 (IP-10) and monocyte chemotactic protein 1 (MCP-1), are useful inflammatory markers for assessing AD severity in infants and young children. To investigate this, we assessed the severity of AD clinically using the SCORing Atopic Dermatitis (SCORAD) index system. Serum chemokine concentrations were determined by sandwich enzyme immunoassay. Twenty AD patients with a median age of 2.1 years [interquartile range (IQR): 0.6-4.2] were recruited. Their SCORAD score was 23.5 (12.5-33.5). Serum concentrations of MDC, TARC, EOX, IP-10 and MCP-1 were 2551 (1978-3935), 1469 (1125-3070), 68 (57-85), 126 (101-226) and 518 (419-614) pg/ml, respectively. Serum MDC levels correlated with SCORAD (r = 0.608, p = 0.004) and its extent (r = 0.629, p = 0.003) and intensity (r = 0.557, p = 0.011) components. Serum TARC concentration showed weaker correlation with extent (r = 0.474, p = 0.035) and intensity (r = 0.465, p = 0.039) of skin involvement but not SCORAD. The median serum levels of MDC (3131 vs. 2394 pg/ml; p = 0.031) and EOX (80 vs. 61 pg/ml; p = 0.046) were also higher in children with moderate as compared with mild AD. The other chemokines did not correlate with AD severity. In conclusion, our results suggest that serum MDC concentration may be a useful inflammatory marker for assessing AD severity in infants and young children. PMID:12911508

  2. Association of haemolytic uraemic syndrome with dysregulation of chemokine receptor expression in circulating monocytes.

    PubMed

    Ramos, Maria Victoria; Ruggieri, Matias; Panek, Analia Cecilia; Mejias, Maria Pilar; Fernandez-Brando, Romina Jimena; Abrey-Recalde, Maria Jimena; Exeni, Andrea; Barilari, Catalina; Exeni, Ramon; Palermo, Marina Sandra

    2015-08-01

    Haemolytic uraemic syndrome (HUS) is the major complication of Escherichia coli gastrointestinal infections that are Shiga toxin (Stx) producing. Monocytes contribute to HUS evolution by producing cytokines that sensitize endothelial cells to Stx action and migration to the injured kidney. As CC chemokine receptors (CCRs) are involved in monocyte recruitment to injured tissue, we analysed the contribution of these receptors to the pathogenesis of HUS. We analysed CCR1, CCR2 and CCR5 expression in peripheral monocytes from HUS patients during the acute period, with healthy children as controls. We observed an increased expression of CCRs per cell in monocytes from HUS patients, accompanied by an increase in the absolute number of monocytes CCR1+, CCR2+ and CCR5+. It is interesting that prospective analysis confirmed that CCR1 expression positively correlated with HUS severity. The evaluation of chemokine levels in plasma showed that regulated on activation of normal T-cell-expressed and -secreted (RANTES) protein was reduced in plasma from patients with severe HUS, and this decrease correlated with thrombocytopenia. Finally, the expression of the higher CCRs was accompanied by a loss of functionality which could be due to a mechanism for desensitization to compensate for altered receptor expression. The increase in CCR expression correlates with HUS severity, suggesting that the dysregulation of these receptors might contribute to an increased risk of renal damage. Activated monocytes could be recruited by chemokines and then receptors could be dysregulated. The dysregulation of CCRs and their ligands observed during the acute period suggests that a chemokine pathway would participate in HUS development.

  3. Biased and G Protein-Independent Signaling of Chemokine Receptors

    PubMed Central

    Steen, Anne; Larsen, Olav; Thiele, Stefanie; Rosenkilde, Mette M.

    2014-01-01

    Biased signaling or functional selectivity occurs when a 7TM-receptor preferentially activates one of several available pathways. It can be divided into three distinct forms: ligand bias, receptor bias, and tissue or cell bias, where it is mediated by different ligands (on the same receptor), different receptors (with the same ligand), or different tissues or cells (for the same ligand–receptor pair). Most often biased signaling is differentiated into G protein-dependent and β-arrestin-dependent signaling. Yet, it may also cover signaling differences within these groups. Moreover, it may not be absolute, i.e., full versus no activation. Here we discuss biased signaling in the chemokine system, including the structural basis for biased signaling in chemokine receptors, as well as in class A 7TM receptors in general. This includes overall helical movements and the contributions of micro-switches based on recently published 7TM crystals and molecular dynamics studies. All three forms of biased signaling are abundant in the chemokine system. This challenges our understanding of “classic” redundancy inevitably ascribed to this system, where multiple chemokines bind to the same receptor and where a single chemokine may bind to several receptors – in both cases with the same functional outcome. The ubiquitous biased signaling confers a hitherto unknown specificity to the chemokine system with a complex interaction pattern that is better described as promiscuous with context-defined roles and different functional outcomes in a ligand-, receptor-, or cell/tissue-defined manner. As the low number of successful drug development plans implies, there are great difficulties in targeting chemokine receptors; in particular with regard to receptor antagonists as anti-inflammatory drugs. Un-defined and putative non-selective targeting of the complete cellular signaling system could be the underlying cause of lack of success. Therefore, biased ligands could be the solution

  4. Lesion progression in apoE-deficient mice: implication of chemokines and effect of the AT1 angiotensin II receptor antagonist irbesartan.

    PubMed

    Martin, Geneviève; Dol, Frédérique; Marés, Anne-Marie; Berezowski, Vincent; Staels, Bart; Hum, Dean W; Schaeffer, Paul; Herbert, Jean-Marc

    2004-02-01

    We recently described that a treatment with the angiotensin AT1 receptor antagonist irbesartan inhibits atherosclerotic lesion development, macrophage accumulation, and monocyte chemoattractant protein-1 (MCP-1) as well as the chemokine KC expression in apolipoprotein E-deficient (apoE-deficient) mice. The present study addresses whether these and other chemokines are expressed not only during the initiation but also during the development of atherosclerotic lesions and whether irbesartan can inhibit the expression of these chemokines during lesion progression. The time course of lesion development was assessed in apoE-deficient mice aged 1 to 9 months and the relative expression of chemokines was quantified by RT-PCR. Significant lesion formation already appeared in 3-month-old apoE-deficient mice, and progressed further to the age of 9 months. The expression of MCP-1 and KC (the mouse homologue of Groalpha), was induced at 1 month in apoE-deficient as compared with wild type (C57/Bl6) mice, and was observed before any detectable histologic changes. MCP-1 and KC expression remained high during lesion progression. The expression of macrophage inflammatory protein-2 (MIP-2, the mouse Grobeta/gamma homologue) and macrophage inflammatory protein-1alpha (MIP-1alpha) was increased in lesions from 4-month-old mice onward, whereas Regulated upon Activation of Normal T-cells Expressed and Secreted (RANTES) was significantly induced in 6- to 9-month-old mice only. Irbesartan (50 mg/kg/d) administered from the age of 3 months onward significantly reduced the progression of the lesions as well as the expression of the chemokines. A short-term treatment with irbesartan significantly inhibited the expression of MCP-1 and KC, suggesting that activation of the renin-angiotensin system is involved in up-regulation of these chemokines and that this effect represents a potential mechanism by which irbesartan inhibits plaque development and progression.

  5. Neutrophils from pulmonary tuberculosis patients show augmented levels of chemokines MIP-1α, IL-8 and MCP-1 which further increase upon in vitro infection with mycobacterial strains.

    PubMed

    Hilda, J Nancy; Narasimhan, Meenakshi; Das, Sulochana D

    2014-08-01

    Neutrophils being innate cells initiate the immune defence against mycobacteria by sending signals to other immune cells. Chemokines being the vital link in signaling processes, it is of interest to study their secretion by neutrophils as a response to tuberculosis infection. The levels of various chemokines (MIP-1α, MCP-1, IL-8 and IP-10) and chemokine receptors (CXCR1, CXCR2 and CCR1) in neutrophils from healthy individuals and pulmonary tuberculosis patients were studied following infection with Mycobacterium tuberculosis strains (clinical--S7 and S10 and laboratory--H37Rv). The release of MIP-1α, IL-8 and MCP-1 is found to be greatly increased in patient neutrophils. Mycobacterial strains differentially influenced neutrophils affecting the release of chemokines to different extent. H37Rv significantly increased the release of MIP-1α and IL-8 in both normals and tuberculosis patients, while S10 up regulated only the release of MIP-1α in patients. Thus, during tuberculosis, neutrophils undergo functional alteration to combat infection. While H37Rv is greatly recognized by neutrophils and triggers the release of chemokines, clinical strains by some means try to suppress immune activation of neutrophils in their favor.

  6. New paradigms in chemokine receptor signal transduction: Moving beyond the two-site model.

    PubMed

    Kleist, Andrew B; Getschman, Anthony E; Ziarek, Joshua J; Nevins, Amanda M; Gauthier, Pierre-Arnaud; Chevigné, Andy; Szpakowska, Martyna; Volkman, Brian F

    2016-08-15

    Chemokine receptor (CKR) signaling forms the basis of essential immune cellular functions, and dysregulated CKR signaling underpins numerous disease processes of the immune system and beyond. CKRs, which belong to the seven transmembrane domain receptor (7TMR) superfamily, initiate signaling upon binding of endogenous, secreted chemokine ligands. Chemokine-CKR interactions are traditionally described by a two-step/two-site mechanism, in which the CKR N-terminus recognizes the chemokine globular core (i.e. site 1 interaction), followed by activation when the unstructured chemokine N-terminus is inserted into the receptor TM bundle (i.e. site 2 interaction). Several recent studies challenge the structural independence of sites 1 and 2 by demonstrating physical and allosteric links between these supposedly separate sites. Others contest the functional independence of these sites, identifying nuanced roles for site 1 and other interactions in CKR activation. These developments emerge within a rapidly changing landscape in which CKR signaling is influenced by receptor PTMs, chemokine and CKR dimerization, and endogenous non-chemokine ligands. Simultaneous advances in the structural and functional characterization of 7TMR biased signaling have altered how we understand promiscuous chemokine-CKR interactions. In this review, we explore new paradigms in CKR signal transduction by considering studies that depict a more intricate architecture governing the consequences of chemokine-CKR interactions. PMID:27106080

  7. New paradigms in chemokine receptor signal transduction: Moving beyond the two-site model.

    PubMed

    Kleist, Andrew B; Getschman, Anthony E; Ziarek, Joshua J; Nevins, Amanda M; Gauthier, Pierre-Arnaud; Chevigné, Andy; Szpakowska, Martyna; Volkman, Brian F

    2016-08-15

    Chemokine receptor (CKR) signaling forms the basis of essential immune cellular functions, and dysregulated CKR signaling underpins numerous disease processes of the immune system and beyond. CKRs, which belong to the seven transmembrane domain receptor (7TMR) superfamily, initiate signaling upon binding of endogenous, secreted chemokine ligands. Chemokine-CKR interactions are traditionally described by a two-step/two-site mechanism, in which the CKR N-terminus recognizes the chemokine globular core (i.e. site 1 interaction), followed by activation when the unstructured chemokine N-terminus is inserted into the receptor TM bundle (i.e. site 2 interaction). Several recent studies challenge the structural independence of sites 1 and 2 by demonstrating physical and allosteric links between these supposedly separate sites. Others contest the functional independence of these sites, identifying nuanced roles for site 1 and other interactions in CKR activation. These developments emerge within a rapidly changing landscape in which CKR signaling is influenced by receptor PTMs, chemokine and CKR dimerization, and endogenous non-chemokine ligands. Simultaneous advances in the structural and functional characterization of 7TMR biased signaling have altered how we understand promiscuous chemokine-CKR interactions. In this review, we explore new paradigms in CKR signal transduction by considering studies that depict a more intricate architecture governing the consequences of chemokine-CKR interactions.

  8. Cloning and expression analysis of three novel CC chemokine genes from Japanese flounder (Paralichthys olivaceus).

    PubMed

    Zou, Gang-gang; Nozaki, Reiko; Kondo, Hidehiro; Hirono, Ikuo

    2014-10-01

    Chemokines are small cytokines secreted by various cell types. They not only function in cell activation, differentiation and trafficking, but they also have influences on many biological processes. In this study, three novel CC chemokine genes Paol-SCYA105, 106 and 107 in Japanese flounder (Paralichthys olivaceus) were cloned and characterized. Paol-SCYA105 was mainly detected in gill, kidney and spleen, Paol-SCYA106 was detected in all tissues examined and Paol-SCYA107 was mainly detected in the spleen and kidney. Paol-SCYA105 and Paol-SCYA106 gene expressions peaked in kidney at day 3 after viral hemorrhagic septicemia virus infection and decreased at day 6, but Paol-SCYA106 still remained at a high level at day 6. Paol-SCYA107 gene expression was significantly up-regulated in kidney at day 6 after viral hemorrhagic septicemia virus infection. In response to infection by Gram-negative Edwardsiella tarda and Gram-positive Streptococcus iniae in kidney, only Paol-SCYA106 gene expression significantly increased. Together, these results indicate that these three novel CC chemokines are involved in the immune response against pathogen infections.

  9. International Union of Basic and Clinical Pharmacology. [corrected]. LXXXIX. Update on the extended family of chemokine receptors and introducing a new nomenclature for atypical chemokine receptors.

    PubMed

    Bachelerie, Francoise; Ben-Baruch, Adit; Burkhardt, Amanda M; Combadiere, Christophe; Farber, Joshua M; Graham, Gerard J; Horuk, Richard; Sparre-Ulrich, Alexander Hovard; Locati, Massimo; Luster, Andrew D; Mantovani, Alberto; Matsushima, Kouji; Murphy, Philip M; Nibbs, Robert; Nomiyama, Hisayuki; Power, Christine A; Proudfoot, Amanda E I; Rosenkilde, Mette M; Rot, Antal; Sozzani, Silvano; Thelen, Marcus; Yoshie, Osamu; Zlotnik, Albert

    2014-01-01

    Sixteen years ago, the Nomenclature Committee of the International Union of Pharmacology approved a system for naming human seven-transmembrane (7TM) G protein-coupled chemokine receptors, the large family of leukocyte chemoattractant receptors that regulates immune system development and function, in large part by mediating leukocyte trafficking. This was announced in Pharmacological Reviews in a major overview of the first decade of research in this field [Murphy PM, Baggiolini M, Charo IF, Hébert CA, Horuk R, Matsushima K, Miller LH, Oppenheim JJ, and Power CA (2000) Pharmacol Rev 52:145-176]. Since then, several new receptors have been discovered, and major advances have been made for the others in many areas, including structural biology, signal transduction mechanisms, biology, and pharmacology. New and diverse roles have been identified in infection, immunity, inflammation, development, cancer, and other areas. The first two drugs acting at chemokine receptors have been approved by the U.S. Food and Drug Administration (FDA), maraviroc targeting CCR5 in human immunodeficiency virus (HIV)/AIDS, and plerixafor targeting CXCR4 for stem cell mobilization for transplantation in cancer, and other candidates are now undergoing pivotal clinical trials for diverse disease indications. In addition, a subfamily of atypical chemokine receptors has emerged that may signal through arrestins instead of G proteins to act as chemokine scavengers, and many microbial and invertebrate G protein-coupled chemokine receptors and soluble chemokine-binding proteins have been described. Here, we review this extended family of chemokine receptors and chemokine-binding proteins at the basic, translational, and clinical levels, including an update on drug development. We also introduce a new nomenclature for atypical chemokine receptors with the stem ACKR (atypical chemokine receptor) approved by the Nomenclature Committee of the International Union of Pharmacology and the Human Genome

  10. International Union of Pharmacology. LXXXIX. Update on the Extended Family of Chemokine Receptors and Introducing a New Nomenclature for Atypical Chemokine Receptors

    PubMed Central

    Bachelerie, Francoise; Ben-Baruch, Adit; Burkhardt, Amanda M.; Combadiere, Christophe; Farber, Joshua M.; Graham, Gerard J.; Horuk, Richard; Sparre-Ulrich, Alexander Hovard; Locati, Massimo; Luster, Andrew D.; Mantovani, Alberto; Matsushima, Kouji; Nibbs, Robert; Nomiyama, Hisayuki; Power, Christine A.; Proudfoot, Amanda E. I.; Rosenkilde, Mette M.; Rot, Antal; Sozzani, Silvano; Thelen, Marcus; Yoshie, Osamu; Zlotnik, Albert

    2014-01-01

    Sixteen years ago, the Nomenclature Committee of the International Union of Pharmacology approved a system for naming human seven-transmembrane (7TM) G protein-coupled chemokine receptors, the large family of leukocyte chemoattractant receptors that regulates immune system development and function, in large part by mediating leukocyte trafficking. This was announced in Pharmacological Reviews in a major overview of the first decade of research in this field [Murphy PM, Baggiolini M, Charo IF, Hébert CA, Horuk R, Matsushima K, Miller LH, Oppenheim JJ, and Power CA (2000) Pharmacol Rev 52:145–176]. Since then, several new receptors have been discovered, and major advances have been made for the others in many areas, including structural biology, signal transduction mechanisms, biology, and pharmacology. New and diverse roles have been identified in infection, immunity, inflammation, development, cancer, and other areas. The first two drugs acting at chemokine receptors have been approved by the U.S. Food and Drug Administration (FDA), maraviroc targeting CCR5 in human immunodeficiency virus (HIV)/AIDS, and plerixafor targeting CXCR4 for stem cell mobilization for transplantation in cancer, and other candidates are now undergoing pivotal clinical trials for diverse disease indications. In addition, a subfamily of atypical chemokine receptors has emerged that may signal through arrestins instead of G proteins to act as chemokine scavengers, and many microbial and invertebrate G protein-coupled chemokine receptors and soluble chemokine-binding proteins have been described. Here, we review this extended family of chemokine receptors and chemokine-binding proteins at the basic, translational, and clinical levels, including an update on drug development. We also introduce a new nomenclature for atypical chemokine receptors with the stem ACKR (atypical chemokine receptor) approved by the Nomenclature Committee of the International Union of Pharmacology and the Human

  11. Differential expression of chemokines, chemokine receptors and proteinases by foreign body giant cells (FBGCs) and osteoclasts.

    PubMed

    Khan, Usman A; Hashimi, Saeed M; Khan, Shershah; Quan, Jingjing; Bakr, Mahmoud M; Forwood, Mark R; Morrison, Nigel M

    2014-07-01

    Osteoclasts and foreign body giant cells (FBGCs) are both derived from the fusion of macropahges. These cells are seen in close proximity during foreign body reactions, therefore it was assumed that they might interact with each other. The aim was to identify important genes that are expressed by osteoclasts and FBGCs which can be used to understand peri-implantitis and predict the relationship of these cells during foreign body reactions. Bone marrow macrophages (BMM) were treated with receptor activator of nuclear factor kappa B ligand (RANKL) to produce osteoclasts. Quantitative PCR (qPCR) was used to identify the genes that were expressed by osteoclasts and FBGCs compared to macrophage controls. TRAP staining was used to visualise the cells while gelatine zymography and western blots were used for protein expression. Tartrate-resistant acid phosphatase (TRAP), matrix metallo proteinase 9 (MMP9), nuclear factor of activated T cells 1 (NFATc1), cathepsin K (CTSK) and RANK were significantly lower in FBGCs compared to osteoclasts. Inflammation specific chemokines such as monocyte chemotactic protein (MCP1 also called CCL2), macrophage inflammatory protein 1 alpha (MIP1α), MIP1β and MIP1γ, and their receptors CCR1, CCR3 and CCR5, were highly expressed by FBGCs. FBGCs were negative for osteoclast specific markers (RANK, NFATc1, CTSK). FBGCs expressed chemokines such as CCL2, 3, 5 and 9 while osteoclasts expressed the receptors for these chemokines i.e. CCR1, 2 and 3. Our findings show that osteoclast specific genes are not expressed by FBGCs and that FBGCs interact with osteoclasts during foreign body reaction through chemokines.

  12. Streptococcal M1 protein triggers chemokine formation, neutrophil infiltration, and lung injury in an NFAT-dependent manner.

    PubMed

    Zhang, Songen; Zhang, Su; Garcia-Vaz, Eliana; Herwald, Heiko; Gomez, Maria F; Thorlacius, Henrik

    2015-06-01

    Streptococcus pyogenes of the M1 serotype can cause STSS, which is associated with significant morbidity and mortality. The purpose of the present study was to examine the role of NFAT signaling in M1 protein-induced lung injury. NFAT-luc mice were treated with the NFAT inhibitor A-285222 before administration of the M1 protein. Neutrophil infiltration, edema, and CXC chemokines were quantified in the lung, 4 h after challenge with the M1 protein. Flow cytometry was used to determine Mac-1 expression. Challenge with the M1 protein increased NFAT-dependent transcriptional activity in the lung, spleen, and liver in NFAT-luc mice. Administration of the NFAT inhibitor A-285222 abolished M1 protein-evoked NFAT activation in the lung, spleen, and liver. M1 protein challenge induced neutrophil recruitment, edema, and CXC chemokine production in the lung, as well as up-regulation of Mac-1 on circulating neutrophils. Inhibition of NFAT activity attenuated M1 protein-induced neutrophil infiltration by 77% and edema formation by 50% in the lung. Moreover, administration of A-285222 reduced M1 protein-evoked pulmonary formation of CXC chemokine >80%. In addition, NFAT inhibition decreased M1 protein-triggered Mac-1 up-regulation on neutrophils. These findings indicate that NFAT signaling controls pulmonary infiltration of neutrophils in response to streptococcal M1 protein via formation of CXC chemokines and neutrophil expression of Mac-1. Thus, the targeting of NFAT activity might be a useful way to ameliorate lung injury in streptococcal infections.

  13. Cytokine and Chemokine Profile in Amicrobial Pustulosis of the Folds

    PubMed Central

    Marzano, Angelo V.; Tavecchio, Simona; Berti, Emilio; Gelmetti, Carlo; Cugno, Massimo

    2015-01-01

    Abstract Autoinflammation has recently been suggested in the pathogenesis of neutrophilic dermatoses but systematic studies on their cytokine profile are lacking. Notably, amicrobial pustulosis of the folds (APF), classified among neutrophilic dermatoses, has been studied only in small case series. In our University Hospital, we conducted an observational study on 15 APF patients, analyzing their clinical and laboratory features with a follow-up of 9 months to 20 years. Skin cytokine pattern of 9 of them was compared to that of 6 normal controls. In all patients, primary lesions were pustules symmetrically involving the skin folds and anogenital region with a chronic-relapsing course and responding to corticosteroids. Dapsone, cyclosporine, and tumor necrosis factor blockers were effective in refractory cases. In skin samples, the expressions of interleukin (IL)-1β, pivotal cytokine in autoinflammation, and its receptors I and II were significantly higher in APF (P = 0.005, 0.018, and 0.034, respectively) than in controls. Chemokines responsible for neutrophil recruitment such as IL-8 (P = 0.003), CXCL 1/2/3 (C-X-C motif ligand 1/2/3) (P = 0.010), CXCL 16 (P = 0.045), and RANTES (regulated on activation, normal T cell expressed and secreted) (P = 0.034) were overexpressed. Molecules involved in tissue damage like matrix metalloproteinase-2 (MMP-2) (P = 0.010) and MMP-9 (P = 0.003) were increased. APF is a pustular neutrophilic dermatosis with a typical distribution in all patients. The disorder may coexist with an underlying autoimmune/dysimmune disease but is often associated only with a few autoantibodies without a clear autoimmunity. The overexpression of cytokines/chemokines and molecules amplifying the inflammatory network supports the view that APF has an important autoinflammatory component. PMID:26683967

  14. Atypical Chemokine Receptors and Their Roles in the Resolution of the Inflammatory Response

    PubMed Central

    Bonecchi, Raffaella; Graham, Gerard J.

    2016-01-01

    Chemokines and their receptors are key mediators of the inflammatory process regulating leukocyte extravasation and directional migration into inflamed and infected tissues. The control of chemokine availability within inflamed tissues is necessary to attain a resolving environment and when this fails chronic inflammation ensues. Accordingly, vertebrates have adopted a number of mechanisms for removing chemokines from inflamed sites to help precipitate resolution. Over the past 15 years, it has become apparent that essential players in this process are the members of the atypical chemokine receptor (ACKR) family. Broadly speaking, this family is expressed on stromal cell types and scavenges chemokines to either limit their spatial availability or to remove them from in vivo sites. Here, we provide a brief review of these ACKRs and discuss their involvement in the resolution of inflammatory responses and the therapeutic implications of our current knowledge. PMID:27375622

  15. Pouncing on the chemokine receptor Chimera.

    PubMed

    Mascolini, M

    1997-08-01

    Scientists are seeking to unravel the mystery of chemokine receptors in an attempt to develop treatments for HIV infection; however, receptor experts are realizing that the picture is more complicated than they first imagined. Scientists want to know, among other things, what parts of each coreceptor are essential for viral fusion with target cells, what makes macrophage-tropic viruses switch their preference to T-lymphocytes, why HIV goes after chemokine receptors in the first place, and how fusion and entry occur. Other issues discussed include whether blocking coreceptors for HIV will actually curb this disease, virus turnover in monkey studies showing that SIV may go through the cycle as many as 100 times per day, and studies showing that the first days of infection may predict the course of disease. Final comments concern the use of ritonavir plus indinavir in treatment combinations for children with HIV and the latest progress toward vaccine development. Understanding these and other puzzles might help scientists to develop drugs to block receptors active in HIV infection and perhaps curb HIV. More than 14 biotechnology and pharmaceutical firms are working to design coreceptor blockers, despite the opinions of several leading researchers that the drugs are not terribly promising. Dr. Anthony Fauci, director of the National Institute for Allergy and Infectious Disease (NIAID), notes that a famous attempt to block HIV's primary receptor failed, and David Ho, the man who demonstrated why CD4 would not work as therapy, is similarly cautious. According to Ho, drug makers will have no trouble developing compounds that keep HIV off chemokine receptors, such as CCR5 or CXCR4, but whether those compounds will slow disease progression is another question. PMID:11364629

  16. 50 CFR 665.964 - Regulated activities.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 50 Wildlife and Fisheries 13 2014-10-01 2014-10-01 false Regulated activities. 665.964 Section 665.964 Wildlife and Fisheries FISHERY CONSERVATION AND MANAGEMENT, NATIONAL OCEANIC AND ATMOSPHERIC ADMINISTRATION, DEPARTMENT OF COMMERCE (CONTINUED) FISHERIES IN THE WESTERN PACIFIC Rose Atoll Marine...

  17. 50 CFR 665.964 - Regulated activities.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 50 Wildlife and Fisheries 13 2013-10-01 2013-10-01 false Regulated activities. 665.964 Section 665.964 Wildlife and Fisheries FISHERY CONSERVATION AND MANAGEMENT, NATIONAL OCEANIC AND ATMOSPHERIC ADMINISTRATION, DEPARTMENT OF COMMERCE (CONTINUED) FISHERIES IN THE WESTERN PACIFIC Rose Atoll Marine...

  18. Stoichiometry and geometry of the CXC chemokine receptor 4 complex with CXC ligand 12: Molecular modeling and experimental validation

    PubMed Central

    Kufareva, Irina; Stephens, Bryan S.; Holden, Lauren G.; Qin, Ling; Zhao, Chunxia; Kawamura, Tetsuya; Abagyan, Ruben; Handel, Tracy M.

    2014-01-01

    Chemokines and their receptors regulate cell migration during development, immune system function, and in inflammatory diseases, making them important therapeutic targets. Nevertheless, the structural basis of receptor:chemokine interaction is poorly understood. Adding to the complexity of the problem is the persistently dimeric behavior of receptors observed in cell-based studies, which in combination with structural and mutagenesis data, suggest several possibilities for receptor:chemokine complex stoichiometry. In this study, a combination of computational, functional, and biophysical approaches was used to elucidate the stoichiometry and geometry of the interaction between the CXC-type chemokine receptor 4 (CXCR4) and its ligand CXCL12. First, relevance and feasibility of a 2:1 stoichiometry hypothesis was probed using functional complementation experiments with multiple pairs of complementary nonfunctional CXCR4 mutants. Next, the importance of dimers of WT CXCR4 was explored using the strategy of dimer dilution, where WT receptor dimerization is disrupted by increasing expression of nonfunctional CXCR4 mutants. The results of these experiments were supportive of a 1:1 stoichiometry, although the latter could not simultaneously reconcile existing structural and mutagenesis data. To resolve the contradiction, cysteine trapping experiments were used to derive residue proximity constraints that enabled construction of a validated 1:1 receptor:chemokine model, consistent with the paradigmatic two-site hypothesis of receptor activation. The observation of a 1:1 stoichiometry is in line with accumulating evidence supporting monomers as minimal functional units of G protein-coupled receptors, and suggests transmission of conformational changes across the dimer interface as the most probable mechanism of altered signaling by receptor heterodimers. PMID:25468967

  19. Stoichiometry and geometry of the CXC chemokine receptor 4 complex with CXC ligand 12: molecular modeling and experimental validation.

    PubMed

    Kufareva, Irina; Stephens, Bryan S; Holden, Lauren G; Qin, Ling; Zhao, Chunxia; Kawamura, Tetsuya; Abagyan, Ruben; Handel, Tracy M

    2014-12-16

    Chemokines and their receptors regulate cell migration during development, immune system function, and in inflammatory diseases, making them important therapeutic targets. Nevertheless, the structural basis of receptor:chemokine interaction is poorly understood. Adding to the complexity of the problem is the persistently dimeric behavior of receptors observed in cell-based studies, which in combination with structural and mutagenesis data, suggest several possibilities for receptor:chemokine complex stoichiometry. In this study, a combination of computational, functional, and biophysical approaches was used to elucidate the stoichiometry and geometry of the interaction between the CXC-type chemokine receptor 4 (CXCR4) and its ligand CXCL12. First, relevance and feasibility of a 2:1 stoichiometry hypothesis was probed using functional complementation experiments with multiple pairs of complementary nonfunctional CXCR4 mutants. Next, the importance of dimers of WT CXCR4 was explored using the strategy of dimer dilution, where WT receptor dimerization is disrupted by increasing expression of nonfunctional CXCR4 mutants. The results of these experiments were supportive of a 1:1 stoichiometry, although the latter could not simultaneously reconcile existing structural and mutagenesis data. To resolve the contradiction, cysteine trapping experiments were used to derive residue proximity constraints that enabled construction of a validated 1:1 receptor:chemokine model, consistent with the paradigmatic two-site hypothesis of receptor activation. The observation of a 1:1 stoichiometry is in line with accumulating evidence supporting monomers as minimal functional units of G protein-coupled receptors, and suggests transmission of conformational changes across the dimer interface as the most probable mechanism of altered signaling by receptor heterodimers.

  20. Structure of mouse IP-10, a chemokine

    SciTech Connect

    Jabeen, Talat; Leonard, Philip; Jamaluddin, Haryati; Acharya, K. Ravi

    2008-06-01

    The structure of mouse IP-10 shows a novel tetrameric association. Interferon-γ-inducible protein (IP-10) belongs to the CXC class of chemokines and plays a significant role in the pathophysiology of various immune and inflammatory responses. It is also a potent angiostatic factor with antifibrotic properties. The biological activities of IP-10 are exerted by interactions with the G-protein-coupled receptor CXCR3 expressed on Th1 lymphocytes. IP-10 thus forms an attractive target for structure-based rational drug design of anti-inflammatory molecules. The crystal structure of mouse IP-10 has been determined and reveals a novel tetrameric association. In the tetramer, two conventional CXC chemokine dimers are associated through their N-terminal regions to form a 12-stranded elongated β-sheet of ∼90 Å in length. This association differs significantly from the previously studied tetramers of human IP-10, platelet factor 4 and neutrophil-activating peptide-2. In addition, heparin- and receptor-binding residues were mapped on the surface of IP-10 tetramer. Two heparin-binding sites were observed on the surface and were present at the interface of each of the two β-sheet dimers. The structure supports the formation of higher order oligomers of IP-10, as observed in recent in vivo studies with mouse IP-10, which will have functional relevance.

  1. (+)-Nootkatone inhibits tumor necrosis factor α/interferon γ-induced production of chemokines in HaCaT cells

    SciTech Connect

    Choi, Hyeon-Jae; Lee, Jin-Hwee; Jung, Yi-Sook

    2014-05-02

    Highlights: • (+)-Nootkatone inhibits TNF-α/IFN-γ-induced TARC and MDC expression in HaCaT cells. • PKCζ, p38 MAPK, or NF-κB mediate TNF-α/IFN-γ-induced TARC and MDC expression. • (+)-Nootkatone inhibits TNF-α/IFN-γ-induced activation of PKCζ, p38 MAPK, or NF-κB. • (+)-Nootkatone suppresses chemokine expression by inhibiting of PKCζ and p38 pathways. - Abstract: Chemokines are important mediators of cell migration, and thymus and activation-regulated chemokine (TARC/CCL17) and macrophage-derived chemokine (MDC/CCL22) are well-known typical inflammatory chemokines involved in atopic dermatitis (AD). (+)-Nootkatone is the major component of Cyperus rotundus. (+)-Nootkatone has antiallergic, anti-inflammatory, and antiplatelet activities. The purpose of this study was to investigate the effect of (+)-nootkatone on tumor necrosis factor α (TNF-α)/interferon γ (IFN-γ)-induced expression of Th2 chemokines in HaCaT cells. We found that (+)-nootkatone inhibited the TNF-α/IFN-γ-induced expression of TARC/CCL17 and MDC/CCL22 mRNA in HaCaT cells. It also significantly inhibited TNF-α/IFN-γ-induced activation of nuclear factor kappa B (NF-κB), p38 mitogen-activated protein kinase (MAPK), and protein kinase Cζ (PKCζ). Furthermore, we showed that PKCζ and p38 MAPK contributed to the inhibition of TNF-α/IFN-γ-induced TARC/CCL17 and MDC/CCL22 expression by blocking IκBα degradation in HaCaT cells. Taken together, these results suggest that (+)-nootkatone may suppress TNF-α/IFN-γ-induced TARC/CCL17 and MDC/CCL22 expression in HaCaT cells by inhibiting of PKCζ and p38 MAPK signaling pathways that lead to activation of NF-κB. We propose that (+)-nootkatone may be a useful therapeutic candidate for inflammatory skin diseases such as AD.

  2. Aryl hydrocarbon receptor signaling regulates NF-κB RelB activation during dendritic-cell differentiation

    PubMed Central

    Vogel, Christoph F A; Wu, Dalei; Goth, Samuel R; Baek, Jaeeun; Lollies, Anna; Domhardt, Rowena; Grindel, Annemarie; Pessah, Isaac N

    2013-01-01

    How the aryl hydrocarbon receptor (AhR) regulates dendritic-cell (DC) differentiation is unknown. We show that activation of AhR by 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) caused enhanced differentiation from immature DCs (IDCs) to mature DCs (MDCs) in the bone-marrow-derived DCs (BMDC) from B6 wild-type mice but not in the BMDCs from AhR-null mice as indicated by the expression of CD11c and class II major histocompatibility complex (MHC). Enhanced maturation of BMDCs was associated with elevated levels of CD86 and an increased AhR-dependent nuclear accumulation of nuclear factor-kappa-light-chain enhancer of activated B cell (NF-κB) member RelB in BMDCs. The expression of interleukin (IL) 10 and chemokine DC-CK1 was suppressed, whereas that of CXCL2, CXCL3 and IL-22 was significantly increased in AhR-activated BMDCs. Furthermore, TCDD induced expression of the regulatory enzymes indoleamine 2,3-dioxygenase (IDO1) and indoleamine 2,3-dioxygenase-like 1 (IDO2). Increased expression of IDO2 was associated with coexpression of the cell-surface marker CCR6. Interestingly, mRNA expression of the chemokine receptor CCR6 was drastically decreased in AhR-null IDCs and MDCs. Overall, these data demonstrate that AhR modifies the maturation of BMDCs associated with the induction of the regulatory enzyme IDO and altered expression of cytokine, chemokines and DC-specific surface markers and receptors. PMID:23999131

  3. Aryl hydrocarbon receptor signaling regulates NF-κB RelB activation during dendritic-cell differentiation.

    PubMed

    Vogel, Christoph F A; Wu, Dalei; Goth, Samuel R; Baek, Jaeeun; Lollies, Anna; Domhardt, Rowena; Grindel, Annemarie; Pessah, Isaac N

    2013-10-01

    How the aryl hydrocarbon receptor (AhR) regulates dendritic-cell (DC) differentiation is unknown. We show that activation of AhR by 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) caused enhanced differentiation from immature DCs (IDCs) to mature DCs (MDCs) in the bone-marrow-derived DCs (BMDC) from B6 wild-type mice but not in the BMDCs from AhR-null mice as indicated by the expression of CD11c and class II major histocompatibility complex (MHC). Enhanced maturation of BMDCs was associated with elevated levels of CD86 and an increased AhR-dependent nuclear accumulation of nuclear factor-kappa-light-chain enhancer of activated B cell (NF-κB) member RelB in BMDCs. The expression of interleukin (IL) 10 and chemokine DC-CK1 was suppressed, whereas that of CXCL2, CXCL3 and IL-22 was significantly increased in AhR-activated BMDCs. Furthermore, TCDD induced expression of the regulatory enzymes indoleamine 2,3-dioxygenase (IDO1) and indoleamine 2,3-dioxygenase-like 1 (IDO2). Increased expression of IDO2 was associated with coexpression of the cell-surface marker CCR6. Interestingly, mRNA expression of the chemokine receptor CCR6 was drastically decreased in AhR-null IDCs and MDCs. Overall, these data demonstrate that AhR modifies the maturation of BMDCs associated with the induction of the regulatory enzyme IDO and altered expression of cytokine, chemokines and DC-specific surface markers and receptors. PMID:23999131

  4. Chemokine CXCL1 mediated neutrophil recruitment: Role of glycosaminoglycan interactions.

    PubMed

    Sawant, Kirti V; Poluri, Krishna Mohan; Dutta, Amit K; Sepuru, Krishna Mohan; Troshkina, Anna; Garofalo, Roberto P; Rajarathnam, Krishna

    2016-01-01

    The chemokine CXCL1/MGSA plays a pivotal role in the host immune response by recruiting and activating neutrophils for microbial killing at the tissue site. CXCL1 exists reversibly as monomers and dimers, and mediates its function by binding glycosaminoglycans (GAG) and CXCR2 receptor. We recently showed that both monomers and dimers are potent CXCR2 agonists, the dimer is the high-affinity GAG ligand, lysine and arginine residues located in two non-overlapping domains mediate GAG interactions, and there is extensive overlap between GAG and receptor-binding domains. To understand how these structural properties influence in vivo function, we characterized peritoneal neutrophil recruitment of a trapped monomer and trapped dimer and a panel of WT lysine/arginine to alanine mutants. Monomers and dimers were active, but WT was more active indicating synergistic interactions promote recruitment. Mutants from both domains showed reduced GAG heparin binding affinities and reduced neutrophil recruitment, providing compelling evidence that both GAG-binding domains mediate in vivo trafficking. Further, mutant of a residue that is involved in both GAG binding and receptor signaling showed the highest reduction in recruitment. We conclude that GAG interactions and receptor activity of CXCL1 monomers and dimers are fine-tuned to regulate neutrophil trafficking for successful resolution of tissue injury. PMID:27625115

  5. Chemokine CXCL1 mediated neutrophil recruitment: Role of glycosaminoglycan interactions

    PubMed Central

    Sawant, Kirti V.; Poluri, Krishna Mohan; Dutta, Amit K.; Sepuru, Krishna Mohan; Troshkina, Anna; Garofalo, Roberto P.; Rajarathnam, Krishna

    2016-01-01

    The chemokine CXCL1/MGSA plays a pivotal role in the host immune response by recruiting and activating neutrophils for microbial killing at the tissue site. CXCL1 exists reversibly as monomers and dimers, and mediates its function by binding glycosaminoglycans (GAG) and CXCR2 receptor. We recently showed that both monomers and dimers are potent CXCR2 agonists, the dimer is the high-affinity GAG ligand, lysine and arginine residues located in two non-overlapping domains mediate GAG interactions, and there is extensive overlap between GAG and receptor-binding domains. To understand how these structural properties influence in vivo function, we characterized peritoneal neutrophil recruitment of a trapped monomer and trapped dimer and a panel of WT lysine/arginine to alanine mutants. Monomers and dimers were active, but WT was more active indicating synergistic interactions promote recruitment. Mutants from both domains showed reduced GAG heparin binding affinities and reduced neutrophil recruitment, providing compelling evidence that both GAG-binding domains mediate in vivo trafficking. Further, mutant of a residue that is involved in both GAG binding and receptor signaling showed the highest reduction in recruitment. We conclude that GAG interactions and receptor activity of CXCL1 monomers and dimers are fine-tuned to regulate neutrophil trafficking for successful resolution of tissue injury. PMID:27625115

  6. Indole-3-carbinol and 3’, 3’-diindolylmethane modulate androgen effect up-regulation on C-C chemokine ligand 2 and monocyte attraction to prostate cancer cells

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Inflammation has a role in prostate tumorigenesis. Recruitment of inflammatory monocytes to the tumor site is mediated by C-C chemokine ligand 2 (CCL2) through binding to its receptor CCR2. We hypothesized that androgen could modulate CCL2 expression in hormone-responsive prostate cancer cells, and ...

  7. Src regulates the activity of SIRT2

    SciTech Connect

    Choi, You Hee; Kim, Hangun; Lee, Sung Ho; Jin, Yun-Hye; Lee, Kwang Youl

    2014-07-25

    Highlights: • Src decreases the protein levels of Sirt2. • Src inhibitor and knockdown of Src increase the protein levels of Sirt2. • Src interacts with and phosphorylates Sirt2. • Src regulate the activity of Sirt2. - Abstract: SIRT2 is a mammalian member of the Sirtuin family of NAD{sup +}-dependent protein deacetylases. The tyrosine kinase Src is involved in a variety of cellular signaling pathways, leading to the induction of DNA synthesis, cell proliferation, and cytoskeletal reorganization. The function of SIRT2 is modulated by post-translational modifications; however, the precise molecular signaling mechanism of SIRT2 through interactions with c-Src has not yet been established. In this study, we investigated the potential regulation of SIRT2 function by c-Src. We found that the protein levels of SIRT2 were decreased by c-Src, and subsequently rescued by the addition of a Src specific inhibitor, SU6656, or by siRNA-mediated knockdown of c-Src. The c-Src interacts with and phosphorylates SIRT2 at Tyr104. c-Src also showed the ability to regulate the deacetylation activity of SIRT2. Investigation on the phosphorylation of SIRT2 suggested that this was the method of c-Src-mediated SIRT2 regulation.

  8. Multiple Glycosaminoglycan-binding Epitopes of Monocyte Chemoattractant Protein-3/CCL7 Enable It to Function as a Non-oligomerizing Chemokine*

    PubMed Central

    Salanga, Catherina L.; Dyer, Douglas P.; Kiselar, Janna G.; Gupta, Sayan; Chance, Mark R.; Handel, Tracy M.

    2014-01-01

    The interaction of chemokines with glycosaminoglycans (GAGs) facilitates the formation of localized chemokine gradients that provide directional signals for migrating cells. In this study, we set out to understand the structural basis and impact of the differing oligomerization propensities of the chemokines monocyte chemoattractant protein (MCP)-1/CCL2 and MCP-3/CCL7 on their ability to bind GAGs. These chemokines provide a unique comparison set because CCL2 oligomerizes and oligomerization is required for its full in vivo activity, whereas CCL7 functions as a monomer. To identify the GAG-binding determinants of CCL7, an unbiased hydroxyl radical footprinting approach was employed, followed by a focused mutagenesis study. Compared with the size of the previously defined GAG-binding epitope of CCL2, CCL7 has a larger binding site, consisting of multiple epitopes distributed along its surface. Furthermore, surface plasmon resonance (SPR) studies indicate that CCL7 is able to bind GAGs with an affinity similar to CCL2 but higher than the non-oligomerizing variant, CCL2(P8A), suggesting that, in contrast to CCL2, the large cluster of GAG-binding residues in CCL7 renders oligomerization unnecessary for high affinity binding. However, the affinity of CCL7 is more sensitive than CCL2 to the density of heparan sulfate on the SPR surfaces; this is likely due to the inability of CCL7 to oligomerize because CCL2(P8A) also binds significantly less tightly to low than high density heparan sulfate surfaces compared with CCL2. Together, the data suggest that CCL7 and CCL2 are non-redundant chemokines and that GAG chain density may provide a mechanism for regulating the accumulation of chemokines on cell surfaces. PMID:24727473

  9. Chemokines in the limbal form of vernal keratoconjunctivitis

    PubMed Central

    El-Asrar, A.; Struyf, S.; Al-Kharashi, S.; Missotten, L.; Van Damme, J.; Geboes, K.

    2000-01-01

    BACKGROUND/AIMS—Chemokines are a family of low molecular weight cytokines that attract and activate leucocytes. The CC chemokines act on eosinophils, basophils, monocytes, and lymphocytes, suggesting that they play an important part in allergic diseases. The aims of this study were to investigate the expression of the CC chemokines, RANTES, eotaxin, monocyte chemotactic protein (MCP) 1, MCP-2, and MCP-3 in the conjunctiva of patients with vernal keratoconjunctivitis (VKC) and to determine the cellular source of these chemokines.
METHODS—Conjunctival biopsy specimens from nine subjects with active VKC, and six control subjects were studied by immunohistochemical techniques using a panel of monoclonal and polyclonal antibodies directed against RANTES, eotaxin, MCP-1, MCP-2, and MCP-3. The phenotype of inflammatory cells expressing chemokines was examined by sequential double immunohistochemistry.
RESULTS—In the normal conjunctiva, superficial epithelial cells showed a constitutive, weak cytoplasmic expression of eotaxin. Few inflammatory cells in the perivascular areas expressed RANTES, MCP-1, MCP-2, and MCP-3. In VKC specimens, the epithelium showed intense cytoplasmic eotaxin staining in all cells, and cytoplasmic RANTES staining mainly in the superficial layers. Furthermore, RANTES and eotaxin were expressed on the vascular endothelium mainly in the upper substantia propria. Compared with normal controls, VKC specimens showed significantly more inflammatory cells expressing RANTES, eotaxin, MCP-1, and MCP-3 (p<0.001, 0.0028, 0.0092, and <0.001, respectively). In VKC specimens, the numbers of inflammatory cells expressing RANTES were significantly higher than the numbers of inflammatory cells expressing eotaxin, MCP-1, and MCP-2 (all p values <0.001). Colocalisation studies revealed that the majority of inflammatory cells expressing chemokines were CD68 positive monocytes/macrophages.
CONCLUSIONS—These results demonstrate an increase in the

  10. The relevance of chemokine signalling in modulating inherited and age-related retinal degenerations.

    PubMed

    Luhmann, Ulrich Fo; Robbie, Scott J; Bainbridge, James Wb; Ali, Robin R

    2014-01-01

    Systemic monocytes, tissue resident macrophages, dendritic cells and microglia have specific roles in immune surveillance and maintenance of tissue homeostasis and are key regulator and effector cells of the local immune response to acute and chronic tissue injury.Two major signalling pathways that differentially define trafficking behaviour and activation of systemic and local myeloid cell populations in response to exogenous and endogenous inflammatory stimuli are the Ccl2-Ccr2 and the Cx3cl1-Cx3cr1 chemokine pathways.Alterations in these pathways have been implicated in controlling myeloid cell activation during normal ageing and in age-related retinal degenerations, including age-related macular degeneration (AMD).We review the evidence for how altered chemokine signalling in acute and chronic inflammatory conditions regulate local and systemic myeloid cell responses in the retina and how this may contribute to or attenuate pathology in inherited and age-related retinal diseases. We discuss the role of environmental factors (e.g. light exposure) and the influence of genetic factors on the manifestation of pathology in experimental models and in human patients and how we envisage harnessing this knowledge for the development of targeted, more broadly applicable anti-inflammatory treatment strategies for a wide range of retinal degenerations.

  11. Identification of a novel CXCL1-like chemokine gene in macaques and its inactivation in hominids.

    PubMed

    Nomiyama, Hisayuki; Otsuka-Ono, Kaori; Miura, Retsu; Osada, Naoki; Terao, Keiji; Yoshie, Osamu; Kusuda, Jun

    2007-01-01

    Chemokines are a rapidly evolving cytokine gene family. Because of various genome rearrangements after divergence of primates and rodents, humans and mice have different sets of chemokine genes, with humans having members outnumbering those of mice. Here, we report the occurrence of lineage-specific chemokine gene generation or inactivation events within primates. By using human chemokine sequences as queries, we isolated a novel cynomolgus macaque CXC chemokine cDNA. The encoded chemokine, termed CXCL1L (from CXCL1-like) showed the highest similarity to human CXCL1. A highly homologous gene was also found in the rhesus macaque genome. By comparing the genome organization of the major CXC chemokine clusters among the primates, we found that one copy of the duplicated CXCL1 genes turned into a pseudogene in the hominids, whereas the gene in macaques has been maintained as a functionally active CXCL1L. In addition, cynomolgus macaque was found to contain an additional CXC chemokine highly homologous to CXCL3, termed CXCL3L (from CXCL3-like). These results demonstrate the birth-and-death process of a new gene in association with gene duplication within the primates.

  12. Defective Chemokine Production in T-Leukemia Cell Lines and its Possible Functional Role

    PubMed Central

    Ivanoff, Jyrki; Ivanoff, Anna

    2000-01-01

    Peripheral blood lymphocytes and T-cell clones produced nanogram quantities of the chemokines RANTES, MIP-lα, MIP-lβ, MCP-l, IL-8 and GRO-α as well as the motogenic cytokine HGF. In contrast, various T-leukemia cell lines at different stages of differentiation did not produce the same chemokines/cytokines. In order to study the possible functional importance of the poor chemokine production different T-cell lines were compared with respect to development of motile forms and migration on extracellular matrix components in the absence and presence of various chemokines. RANTES, MIP-1α, MIP-1β, IL-8, GRO-α and lymphotactin did not augment the development of motile forms including the size and appearance of the pseudopodia activity of the T-leukemia cell lines. The T-cell lines migrated spontaneously on/to fibronectin in a Boyden chamber assay system. Chemokines augmented the migration of the T-leukemia cell lines on fibronectin in the Boyden system in a chemotactic fashion with peak responses at 10 to 50 ng/ml. Thus, the production of chemokines is defective, in neoplastic T-lymphocytes. The defective chemokine production does not seem to play any major role for the basic locomotor capacity of the cells but may modulate the responsiveness to exogenous chemokines. PMID:11097202

  13. Regulators of Slc4 bicarbonate transporter activity

    PubMed Central

    Thornell, Ian M.; Bevensee, Mark O.

    2015-01-01

    The Slc4 family of transporters is comprised of anion exchangers (AE1-4), Na+-coupled bicarbonate transporters (NCBTs) including electrogenic Na/bicarbonate cotransporters (NBCe1 and NBCe2), electroneutral Na/bicarbonate cotransporters (NBCn1 and NBCn2), and the electroneutral Na-driven Cl-bicarbonate exchanger (NDCBE), as well as a borate transporter (BTR1). These transporters regulate intracellular pH (pHi) and contribute to steady-state pHi, but are also involved in other physiological processes including CO2 carriage by red blood cells and solute secretion/reabsorption across epithelia. Acid-base transporters function as either acid extruders or acid loaders, with the Slc4 proteins moving HCO−3 either into or out of cells. According to results from both molecular and functional studies, multiple Slc4 proteins and/or associated splice variants with similar expected effects on pHi are often found in the same tissue or cell. Such apparent redundancy is likely to be physiologically important. In addition to regulating pHi, a HCO−3 transporter contributes to a cell's ability to fine tune the intracellular regulation of the cotransported/exchanged ion(s) (e.g., Na+ or Cl−). In addition, functionally similar transporters or splice variants with different regulatory profiles will optimize pH physiology and solute transport under various conditions or within subcellular domains. Such optimization will depend on activated signaling pathways and transporter expression profiles. In this review, we will summarize and discuss both well-known and more recently identified regulators of the Slc4 proteins. Some of these regulators include traditional second messengers, lipids, binding proteins, autoregulatory domains, and less conventional regulators. The material presented will provide insight into the diversity and physiological significance of multiple members within the Slc4 gene family. PMID:26124722

  14. Simian cytomegalovirus encodes five rapidly evolving chemokine receptor homologues.

    PubMed

    Sahagun-Ruiz, Alfredo; Sierra-Honigmann, Ana Maria; Krause, Philip; Murphy, Philip M

    2004-01-01

    Many herpesviruses, poxviruses and retroviruses encode proteins related to chemokines and chemokine receptors. The first one discovered, US28 of human cytomegalovirus (HCMV), is a 7-transmembrane domain G protein-coupled chemokine receptor able to activate diverse cellular responses, including cell migration and gene expression. A related ORF named US27 is adjacent to US28, but no functions have been defined yet. Recently ORFs 3-7, a cluster of five concatenated ORFs with highest homology to US28 and mammalian chemokine receptors, were sequenced from a prototype "stealth virus", an African green monkey simian CMV (SCMV)-related entity with unusual fungal, bacterial and mammalian gene homologues. Stealth viruses have not yet been independently replicated in tissue culture, and therefore their biological significance remains unclear. ORF3, ORF4, ORF5 and ORF6 are complete ORFs whereas the sequence of ORF7 is incomplete. In the present study, we identified five corresponding ORFs in the genome of a clinical isolate of bonafide simian CMV (SCMV), strain 9610. We found substantial differences between the SCMV and "stealth virus" ORFs, especially for ORF5 where there are 31% non-identities at the amino acid level. Four conserved genes unrelated to chemokines (64K/CAP, DNBI, UL32, and IE2) in SCMV and HCMV had on average 52% identity at the deduced amino acid level, whereas the corresponding values for the SCMV ORFs versus US28 ranged from 21% to 30%, suggesting rapid gene diversification in this cluster. Consistent with this, the amino acid identity for any pairwise comparison among the SCMV ORFs is only 21-52%. The chemokine receptor homologues are estimated to comprise approximately 2-3% of the SCMV genome. HCMV US27 and US28 homologues have also been identified in the chimpanzee CMV genome, whereas mouse and rat CMV lack chemokine receptor homologues. This genomic analysis indicates that SCMV has an unusually high concentration of US28-related chemokine receptor

  15. Anti-infective peptide IDR-1002 augments monocyte chemotaxis towards CCR5 chemokines.

    PubMed

    Madera, Laurence; Hancock, Robert E W

    2015-08-28

    Innate defense regulator (IDR) peptides are a class of immunomodulators which enhance and modulate host innate immune responses against microbial pathogens. While IDR-mediated protection against a range of bacterial pathogens is dependent on enhanced monocyte recruitment to the site of infection, the mechanisms through which they increase monocyte trafficking remain unclear. In this study, anti-infective peptide IDR-1002 was shown to enhance monocyte chemotaxis towards chemokines CCL3 and CCL5. This enhancement correlated with the selective upregulation of CCR5 surface expression by peptide-treated monocytes. It was found that IDR-1002 enhancement of monocyte chemotaxis was fully dependent on CCR5 function. Furthermore, IDR-1002 enhanced chemokine-induced monocyte p38 MAPK phosphorylation in a CCR5-dependent fashion. Overall, these results indicate that peptide IDR-1002 can selectively influence monocyte recruitment by host chemokines through the regulation of chemokine receptors. PMID:26168734

  16. Team Regulation, Regulation of Social Activities or Co-Regulation: Different Labels for Effective Regulation of Learning in CSCL

    ERIC Educational Resources Information Center

    Saab, Nadira

    2012-01-01

    Computer-supported collaborative learning (CSCL) is an approach to learning in which learners can actively and collaboratively construct knowledge by means of interaction and joint problem solving. Regulation of learning is especially important in the domain of CSCL. Next to the regulation of task performance, the interaction between learners who…

  17. Identification and expression analysis of a CC chemokine from cobia (Rachycentron canadum).

    PubMed

    Feng, Juan; Su, Youlu; Guo, Zhixun; Xu, Liwen; Sun, Xiuxiu; Wang, Yunxin

    2013-06-01

    Chemokines are small, secreted cytokine peptides known principally for their ability to induce migration and activation of leukocyte populations and regulate the immune response mechanisms. The cobia (Rachycentron canadum), a marine finfish species, has a great potential for net cage aquaculture in the South China Sea. We isolated and characterized a CC chemokine cDNA from cobia-designated RcCC2. Its cDNA is 783 bp in length and encodes a putative protein of 110 amino acids. Homology and phylogenetic analysis revealed that the RcCC2 gene, which contains four conserved cysteine residues, shares a high degree of similarity with other known CC chemokine sequences and is closest to the CCL19/21 clade. The mRNA of RcCC2 is expressed constitutively in all tested tissues, including gill, liver, muscle, spleen, kidney, head kidney, skin, brain, stomach, intestine and heart, but not blood, with the highest level of expression in gill and liver. The reverse transcription quantitative polymerase chain reaction was used to examine the expression of the RcCC2 gene in immune-related tissues, including head kidney, spleen and liver, following intraperitoneal injection of the viral mimic polyriboinosinic polyribocytidylic acid, formalin-killed Vibrio carchariae (bacterial vaccine) and phosphate-buffered saline as a control. RcCC2 gene expression was up-regulated differentially in head kidney, spleen and liver during 12 h after challenge. These results indicate that the RcCC2 gene is inducible and is involved in immune responses, suggesting RcCC2 has an important role in the early stage of viral and bacterial infections.

  18. Chemokines as Therapeutic Targets to Improve Healing Efficiency of Chronic Wounds

    PubMed Central

    Satish, Latha

    2015-01-01

    Significance: Impaired wound healing leading to chronic wounds is an important clinical problem that needs immediate attention to develop new effective therapies. Members of the chemokine family seem to be attractive and amenable to stimulate the healing process in chronic wounds. Targeting specific chemokines and/or their receptors has the potential to modify chronic inflammation to acute inflammation, which will hasten the healing process. Recent Advances: Over the years, expression levels of various chemokines and their receptors have been identified as key players in the inflammatory phase of wound healing. In addition, they contribute to regulating other phases of wound healing making them key targets for novel therapies. Understanding the signaling pathways of these chemokines will provide valuable clues for modulating their function to enhance the wound healing process. Critical Issues: Inflammation, an important first-stage process in wound healing, is dysregulated in chronic wounds; emerging studies show that chemokines play a crucial role in regulating inflammation. The knowledge gained so far is still limited in understanding the enormous complexity of the chemokine network during inflammation not just in chronic wounds but also in acute (normal) wounds. A much better understanding of the individual chemokines will pave the way for better targets and therapies to improve the healing efficiency of chronic wounds. Future Directions: Effective understanding of the interaction of chemokines and their receptors during chronic wound healing would facilitate the design of novel therapeutic drugs. Development of chemokine-based drugs targeting specific inflammatory cells will be invaluable in the treatment of chronic wounds, in which inflammation plays a major role. PMID:26543679

  19. Activities and regulation of peptidoglycan synthases

    PubMed Central

    Egan, Alexander J. F.; Biboy, Jacob; van't Veer, Inge; Breukink, Eefjan; Vollmer, Waldemar

    2015-01-01

    Peptidoglycan (PG) is an essential component in the cell wall of nearly all bacteria, forming a continuous, mesh-like structure, called the sacculus, around the cytoplasmic membrane to protect the cell from bursting by its turgor. Although PG synthases, the penicillin-binding proteins (PBPs), have been studied for 70 years, useful in vitro assays for measuring their activities were established only recently, and these provided the first insights into the regulation of these enzymes. Here, we review the current knowledge on the glycosyltransferase and transpeptidase activities of PG synthases. We provide new data showing that the bifunctional PBP1A and PBP1B from Escherichia coli are active upon reconstitution into the membrane environment of proteoliposomes, and that these enzymes also exhibit DD-carboxypeptidase activity in certain conditions. Both novel features are relevant for their functioning within the cell. We also review recent data on the impact of protein–protein interactions and other factors on the activities of PBPs. As an example, we demonstrate a synergistic effect of multiple protein–protein interactions on the glycosyltransferase activity of PBP1B, by its cognate lipoprotein activator LpoB and the essential cell division protein FtsN. PMID:26370943

  20. Molecular mechanisms regulating NLRP3 inflammasome activation

    PubMed Central

    Jo, Eun-Kyeong; Kim, Jin Kyung; Shin, Dong-Min; Sasakawa, Chihiro

    2016-01-01

    Inflammasomes are multi-protein signaling complexes that trigger the activation of inflammatory caspases and the maturation of interleukin-1β. Among various inflammasome complexes, the NLRP3 inflammasome is best characterized and has been linked with various human autoinflammatory and autoimmune diseases. Thus, the NLRP3 inflammasome may be a promising target for anti-inflammatory therapies. In this review, we summarize the current understanding of the mechanisms by which the NLRP3 inflammasome is activated in the cytosol. We also describe the binding partners of NLRP3 inflammasome complexes activating or inhibiting the inflammasome assembly. Our knowledge of the mechanisms regulating NLRP3 inflammasome signaling and how these influence inflammatory responses offers further insight into potential therapeutic strategies to treat inflammatory diseases associated with dysregulation of the NLRP3 inflammasome. PMID:26549800

  1. Role of Conserved Disulfide Bridges and Aromatic Residues in Extracellular Loop 2 of Chemokine Receptor CCR8 for Chemokine and Small Molecule Binding.

    PubMed

    Barington, Line; Rummel, Pia C; Lückmann, Michael; Pihl, Heidi; Larsen, Olav; Daugvilaite, Viktorija; Johnsen, Anders H; Frimurer, Thomas M; Karlshøj, Stefanie; Rosenkilde, Mette M

    2016-07-29

    Chemokine receptors play important roles in the immune system and are linked to several human diseases. The initial contact of chemokines with their receptors depends on highly specified extracellular receptor features. Here we investigate the importance of conserved extracellular disulfide bridges and aromatic residues in extracellular loop 2 (ECL-2) for ligand binding and activation in the chemokine receptor CCR8. We used inositol 1,4,5-trisphosphate accumulation and radioligand binding experiments to determine the impact of receptor mutagenesis on both chemokine and small molecule agonist and antagonist binding and action in CCR8. We find that the seven-transmembrane (TM) receptor conserved disulfide bridge (7TM bridge) linking transmembrane helix III (TMIII) and ECL-2 is crucial for chemokine and small molecule action, whereas the chemokine receptor conserved disulfide bridge between the N terminus and TMVII is needed only for chemokines. Furthermore, we find that two distinct aromatic residues in ECL-2, Tyr(184) (Cys + 1) and Tyr(187) (Cys + 4), are crucial for binding of the CC chemokines CCL1 (agonist) and MC148 (antagonist), respectively, but not for small molecule binding. Finally, using in silico modeling, we predict an aromatic cluster of interaction partners for Tyr(187) in TMIV (Phe(171)) and TMV (Trp(194)). We show in vitro that these residues are crucial for the binding and action of MC148, thus supporting their participation in an aromatic cluster with Tyr(187) This aromatic cluster appears to be present in a large number of CC chemokine receptors and thereby could play a more general role to be exploited in future drug development targeting these receptors. PMID:27226537

  2. Magnetoreception Regulates Male Courtship Activity in Drosophila.

    PubMed

    Wu, Chia-Lin; Fu, Tsai-Feng; Chiang, Meng-Hsuan; Chang, Yu-Wei; Her, Jim-Long; Wu, Tony

    2016-01-01

    The possible neurological and biophysical effects of magnetic fields on animals is an area of active study. Here, we report that courtship activity of male Drosophila increases in a magnetic field and that this effect is regulated by the blue light-dependent photoreceptor cryptochrome (CRY). Naïve male flies exhibited significantly increased courtship activities when they were exposed to a ≥ 20-Gauss static magnetic field, compared with their behavior in the natural environment (0 Gauss). CRY-deficient flies, cryb and crym, did not show an increased courtship index in a magnetic field. RNAi-mediated knockdown of cry in cry-GAL4-positive neurons disrupted the increased male courtship activity in a magnetic field. Genetically expressing cry under the control of cry-GAL4 in the CRY-deficient flies restored the increase in male courtship index that occurred in a magnetic field. Interestingly, artificially activating cry-GAL4-expressing neurons, which include large ventral lateral neurons and small ventral lateral neurons, via expression of thermosensitive cation channel dTrpA1, also increased the male courtship index. This enhancement was abolished by the addition of the cry-GAL80 transgene. Our results highlight the phenomenon of increased male courtship activity caused by a magnetic field through CRY-dependent magnetic sensation in CRY expression neurons in Drosophila. PMID:27195955

  3. Magnetoreception Regulates Male Courtship Activity in Drosophila

    PubMed Central

    Wu, Chia-Lin; Fu, Tsai-Feng; Chiang, Meng-Hsuan; Chang, Yu-Wei; Her, Jim-Long; Wu, Tony

    2016-01-01

    The possible neurological and biophysical effects of magnetic fields on animals is an area of active study. Here, we report that courtship activity of male Drosophila increases in a magnetic field and that this effect is regulated by the blue light-dependent photoreceptor cryptochrome (CRY). Naïve male flies exhibited significantly increased courtship activities when they were exposed to a ≥ 20-Gauss static magnetic field, compared with their behavior in the natural environment (0 Gauss). CRY-deficient flies, cryb and crym, did not show an increased courtship index in a magnetic field. RNAi-mediated knockdown of cry in cry-GAL4-positive neurons disrupted the increased male courtship activity in a magnetic field. Genetically expressing cry under the control of cry-GAL4 in the CRY-deficient flies restored the increase in male courtship index that occurred in a magnetic field. Interestingly, artificially activating cry-GAL4-expressing neurons, which include large ventral lateral neurons and small ventral lateral neurons, via expression of thermosensitive cation channel dTrpA1, also increased the male courtship index. This enhancement was abolished by the addition of the cry-GAL80 transgene. Our results highlight the phenomenon of increased male courtship activity caused by a magnetic field through CRY-dependent magnetic sensation in CRY expression neurons in Drosophila. PMID:27195955

  4. Regulation of pokemon 1 activity by sumoylation.

    PubMed

    Roh, Hee-Eun; Lee, Min-Nyung; Jeon, Bu-Nam; Choi, Won-Il; Kim, Yoo-Jin; Yu, Mi-Young; Hur, Man-Wook

    2007-01-01

    Pokemon 1 is a proto-oncogenic transcriptional regulator that contains a POZ domain at the N-terminus and four Kruppel-like zinc fingers at the C-terminus. Pokemon 1 plays an important role in adipogenesis, osteogenesis, oncogenesis, and transcription of NF-kB responsive genes. Recent reports have shown that biological activities of transcription factors are regulated by sumolylation. We investigated whether Pokemon 1 is post-translationally modified by sumoylation and whether the modification affects Pokemon 1's transcriptional properties. We found that Pokemon 1 is sumoylated in vitro and in vivo. Upon careful analysis of the amino acid sequence of Pokemon 1, we found ten potential sumoylation sites located at lysines 61, 354, 371, 379, 383, 396, 486, 487, 536 and 539. We mutated each of these amino acids into arginine and tested whether the mutation could affect the transcriptional properties of Pokemon 1 on the Pokemon 1 responsive genes, such as ADH5/FDH and pG5-FRE-Luc. Wild-type Pokemon 1 potently represses transcription of ADH5/FDH. Most of the mutants, however, were weaker transcription repressors and repressed transcription 1.3-3.3 fold less effective. Although potential sumoylation sites were located close to the DNA binding domain or the nuclear localization sequence, the mutations did not alter nuclear localization or DNA binding activity. In addition, on the pG5-FRE-Luc test promoter construct, ectopic SUMO-1 repressed transcription in the presence of Pokemon 1. The sumoylation target lysine residue at amino acid 61, which is located in the middle of the POZ-domain, is important because K61R mutation resulted in a much weaker molecular interaction with corepressors. Our data suggest that Pokemon 1's activity as a transcription factor may involve sumoylation, and that sumoylation might be important in the regulation of transcription by Pokemon 1. PMID:17595526

  5. Regulation of pokemon 1 activity by sumoylation.

    PubMed

    Roh, Hee-Eun; Lee, Min-Nyung; Jeon, Bu-Nam; Choi, Won-Il; Kim, Yoo-Jin; Yu, Mi-Young; Hur, Man-Wook

    2007-01-01

    Pokemon 1 is a proto-oncogenic transcriptional regulator that contains a POZ domain at the N-terminus and four Kruppel-like zinc fingers at the C-terminus. Pokemon 1 plays an important role in adipogenesis, osteogenesis, oncogenesis, and transcription of NF-kB responsive genes. Recent reports have shown that biological activities of transcription factors are regulated by sumolylation. We investigated whether Pokemon 1 is post-translationally modified by sumoylation and whether the modification affects Pokemon 1's transcriptional properties. We found that Pokemon 1 is sumoylated in vitro and in vivo. Upon careful analysis of the amino acid sequence of Pokemon 1, we found ten potential sumoylation sites located at lysines 61, 354, 371, 379, 383, 396, 486, 487, 536 and 539. We mutated each of these amino acids into arginine and tested whether the mutation could affect the transcriptional properties of Pokemon 1 on the Pokemon 1 responsive genes, such as ADH5/FDH and pG5-FRE-Luc. Wild-type Pokemon 1 potently represses transcription of ADH5/FDH. Most of the mutants, however, were weaker transcription repressors and repressed transcription 1.3-3.3 fold less effective. Although potential sumoylation sites were located close to the DNA binding domain or the nuclear localization sequence, the mutations did not alter nuclear localization or DNA binding activity. In addition, on the pG5-FRE-Luc test promoter construct, ectopic SUMO-1 repressed transcription in the presence of Pokemon 1. The sumoylation target lysine residue at amino acid 61, which is located in the middle of the POZ-domain, is important because K61R mutation resulted in a much weaker molecular interaction with corepressors. Our data suggest that Pokemon 1's activity as a transcription factor may involve sumoylation, and that sumoylation might be important in the regulation of transcription by Pokemon 1.

  6. Enhancement of Chemokine Function as an Immunomodulatory Strategy Employed by Human Herpesviruses

    PubMed Central

    Viejo-Borbolla, Abel; Martinez-Martín, Nadia; Nel, Hendrik J.; Rueda, Patricia; Martín, Rocío; Blanco, Soledad; Arenzana-Seisdedos, Fernando; Thelen, Marcus; Fallon, Padraic G.; Alcamí, Antonio

    2012-01-01

    Herpes simplex virus (HSV) types 1 and 2 are highly prevalent human neurotropic pathogens that cause a variety of diseases, including lethal encephalitis. The relationship between HSV and the host immune system is one of the main determinants of the infection outcome. Chemokines play relevant roles in antiviral response and immunopathology, but the modulation of chemokine function by HSV is not well understood. We have addressed the modulation of chemokine function mediated by HSV. By using surface plasmon resonance and crosslinking assays we show that secreted glycoprotein G (SgG) from both HSV-1 and HSV-2 binds chemokines with high affinity. Chemokine binding activity was also observed in the supernatant of HSV-2 infected cells and in the plasma membrane of cells infected with HSV-1 wild type but not with a gG deficient HSV-1 mutant. Cell-binding and competition experiments indicate that the interaction takes place through the glycosaminoglycan-binding domain of the chemokine. The functional relevance of the interaction was determined both in vitro, by performing transwell assays, time-lapse microscopy, and signal transduction experiments; and in vivo, using the air pouch model of inflammation. Interestingly, and in contrast to what has been observed for previously described viral chemokine binding proteins, HSV SgGs do not inhibit chemokine function. On the contrary, HSV SgGs enhance chemotaxis both in vitro and in vivo through increasing directionality, potency and receptor signaling. This is the first report, to our knowledge, of a viral chemokine binding protein from a human pathogen that increases chemokine function and points towards a previously undescribed strategy of immune modulation mediated by viruses. PMID:22319442

  7. Chemokine gene expression in the brains of mice with lymphocytic choriomeningitis.

    PubMed Central

    Asensio, V C; Campbell, I L

    1997-01-01

    Chemokines are pivotal in the trafficking of leukocytes. In the present study, we examined the expression of multiple chemokine genes during the course of lymphocytic choriomeningitis (LCM) in mice. In noninfected mice, no detectable chemokine gene expression was found in the brain; however, by day 3 postinfection, the induction of a number of chemokine mRNAs was observed as follows (in order from the greatest to the least): cytokine responsive gene-2 or interferon-inducible 10-kDa protein (Crg-2/IP-10), RANTES, monocyte chemotactic protein-1 (MCP-1), macrophage inflammatory protein-1 (MIP-1beta), and MCP-3. At day 6 postinfection, the expression of these chemokine mRNAs was increased, and low expression of lymphotactin, C10, MIP-2, and MIP-1alpha mRNAs was detectable. Transcript for T-cell activation-3 was not detectable in the brain at any time following LCM virus (LCMV) infection. With some exceptions, a pattern of chemokine gene expression similar to that in the brain was observed in the peripheral organs of LCMV-infected mice. Mice that lacked expression of gamma interferon developed LCM and had a qualitatively similar but quantitatively reduced cerebral chemokine gene expression profile. In contrast, little or no chemokine gene expression was detectable in the brains of LCMV-infected athymic mice which did not develop LCM. Expression of Crg-2/IP-10 RNA was localized to predominantly resident cells of the central nervous system (CNS) and overlapped with sites of viral infection and immune cell infiltration. These findings demonstrate the expression of a number of chemokine genes in the brains of mice infected with LCMV. The pattern of chemokine gene expression in LCM may profoundly influence the characteristic phenotype and response of leukocytes in the brain and contribute to the immunopathogenesis of this fatal CNS infection. PMID:9311871

  8. Comparative study of CXC chemokines modulation in brown trout (Salmo trutta) following infection with a bacterial or viral pathogen.

    PubMed

    Gorgoglione, Bartolomeo; Zahran, Eman; Taylor, Nick G H; Feist, Stephen W; Zou, Jun; Secombes, Christopher J

    2016-03-01

    Chemokine modulation in response to pathogens still needs to be fully characterised in fish, in view of the recently described novel chemokines present. This paper reports the first comparative study of CXC chemokine genes transcription in salmonids (brown trout), with a particular focus on the fish specific CXC chemokines (CXCL_F). Adopting new primer sets, optimised to specifically target mRNA, a RT-qPCR gene screening was carried out. Constitutive gene expression was assessed first in six tissues from SPF brown trout. Transcription modulation was next investigated in kidney and spleen during septicaemic infection induced by a RNA virus (Viral Haemorrhagic Septicaemia virus, genotype Ia) or by a Gram negative bacterium (Yersinia ruckeri, ser. O1/biot. 2). From each target organ specific pathogen burden, measured detecting VHSV-glycoprotein or Y. ruckeri 16S rRNA, and IFN-γ gene expression were analysed for their correlation to chemokine transcription. Both pathogens modulated CXC chemokine gene transcript levels, with marked up-regulation seen in some cases, and with both temporal and tissue specific effects apparent. For example, Y. ruckeri strongly induced chemokine transcription in spleen within 24h, whilst VHS generally induced the largest increases at 3d.p.i. in both tissues. This study gives clues to the role of the novel CXC chemokines, in comparison to the other known CXC chemokines in salmonids. PMID:26866873

  9. Comparative study of CXC chemokines modulation in brown trout (Salmo trutta) following infection with a bacterial or viral pathogen.

    PubMed

    Gorgoglione, Bartolomeo; Zahran, Eman; Taylor, Nick G H; Feist, Stephen W; Zou, Jun; Secombes, Christopher J

    2016-03-01

    Chemokine modulation in response to pathogens still needs to be fully characterised in fish, in view of the recently described novel chemokines present. This paper reports the first comparative study of CXC chemokine genes transcription in salmonids (brown trout), with a particular focus on the fish specific CXC chemokines (CXCL_F). Adopting new primer sets, optimised to specifically target mRNA, a RT-qPCR gene screening was carried out. Constitutive gene expression was assessed first in six tissues from SPF brown trout. Transcription modulation was next investigated in kidney and spleen during septicaemic infection induced by a RNA virus (Viral Haemorrhagic Septicaemia virus, genotype Ia) or by a Gram negative bacterium (Yersinia ruckeri, ser. O1/biot. 2). From each target organ specific pathogen burden, measured detecting VHSV-glycoprotein or Y. ruckeri 16S rRNA, and IFN-γ gene expression were analysed for their correlation to chemokine transcription. Both pathogens modulated CXC chemokine gene transcript levels, with marked up-regulation seen in some cases, and with both temporal and tissue specific effects apparent. For example, Y. ruckeri strongly induced chemokine transcription in spleen within 24h, whilst VHS generally induced the largest increases at 3d.p.i. in both tissues. This study gives clues to the role of the novel CXC chemokines, in comparison to the other known CXC chemokines in salmonids.

  10. Regulation of Aicda expression and AID activity.

    PubMed

    Zan, Hong; Casali, Paolo

    2013-03-01

    Activation-induced cytidine deaminase (AID) is expressed in a B cell differentiation stage-specific fashion and is essential for immunoglobulin (Ig) gene class switch DNA recombination (CSR) and somatic hypermutation (SHM). CSR and SHM play a central role in the maturation of antibody and autoantibody responses. AID displays a mutagenic activity by catalyzing targeted deamination of deoxycytidine (dC) residues in DNA resulting in dU:dG mismatches, which are processed into point-mutations in SHM or double-strand breaks (DSBs) in CSR. Although AID specifically targets the Ig gene loci (IgH, Igκ and Igλ), it can also home into a wide array of non-Ig genes in B-and non-B-cell backgrounds. Aberrant expression of AID is associated with multiple diseases such as allergy, inflammation, autoimmunity and cancer. In autoimmune systemic lupus erythematosus, dysregulated AID expression underpins increased CSR, SHM and autoantibody production. As a potent mutator, AID is under stringent transcriptional, post-transcriptional and post-translational regulation. AID is also regulated in its targeting and enzymatic function. In resting naïve or memory B cells, AID transcripts and protein are undetectable. These, however, are readily and significantly up-regulated in B cells induced to undergo CSR and/or SHM. Transcription factors, such as HoxC4 and NF-κB, which are up-regulated in a B cell lineage-and/or differentiation stage-specific manner, regulate the induction of AID. HoxC4 induces AID expression by directly binding to the AID gene promoter through an evolutionarily conserved 5'-ATTT-3' motif. HoxC4 is induced by the same stimuli that induce AID and CSR. It is further up-regulated by estrogen through three estrogen responsive elements in its promoter region. The targeting of AID to switch (S) regions is mediated by 14-3-3 adaptor proteins, which specifically bind to 5'-AGCT-3' repeats that are exist at high frequency in S region cores. Like HoxC4, 14-3-3 adaptors are induced

  11. Analysis of CC chemokine and chemokine receptor expression in solid ovarian tumours

    PubMed Central

    Scotton, C; Milliken, D; Wilson, J; Raju, S; Balkwill, F

    2001-01-01

    To understand the chemokine network in a tissue, both chemokine and chemokine receptor expression should be studied. Human epithelial ovarian tumours express a range of chemokines but little is known about the expression and localisation of chemokine receptors. With the aim of understanding chemokine action in this cancer, we investigated receptors for CC–chemokines and their ligands in 25 biopsies of human ovarian cancer. CC–chemokine receptor mRNA was generally absent from solid tumours, the exception being CCR1 which was detected in samples from 75% of patients. CCR1 mRNA localised to macrophages and lymphocytes and there was a correlation between numbers of CD8+ and CCR1 expressing cells (P = 0.031). mRNA for 6 CC-chemokines was expressed in a majority of tumour samples. In a monocytic cell line in vitro, we found that CCR1 mRNA expression was increased 5-fold by hypoxia. We suggest that the CC-chemokine network in ovarian cancer is controlled at the level of CC-chemokine receptors and this may account for the phenotypes of infiltrating cells found in these tumours. The leukocyte infiltrate may contribute to tumour growth and spread by providing growth survival factors and matrix metalloproteases. Thus, CCR1 may be a novel therapeutic target in ovarian cancer. http://www.bjcancer.com © 2001 Cancer Research Campaignhttp://www.bjcancer.com PMID:11556842

  12. Regulation of polymorphonuclear cell activation by thrombopoietin.

    PubMed Central

    Brizzi, M F; Battaglia, E; Rosso, A; Strippoli, P; Montrucchio, G; Camussi, G; Pegoraro, L

    1997-01-01

    Thrombopoietin (TPO) regulates early and late stages of platelet formation as well as platelet activation. TPO exerts its effects by binding to the receptor, encoded by the protooncogene c-mpl, that is expressed in a large number of cells of hematopoietic origin. In this study, we evaluated the expression of c-Mpl and the effects of TPO on human polymorphonuclear cells (PMN). We demonstrate that PMN express the TPO receptor c-Mpl and that TPO induces STAT1 tyrosine phosphorylation and the formation of a serum inducible element complex containing STAT1. The analysis of biological effects of TPO on PMN demonstrated that TPO, at concentrations of 1-10 ng/ml, primes the response of PMN to n-formyl-met-leu-phe (FMLP) by inducing an early oxidative burst. TPO-induced priming on FMLP-stimulated PMN was also detected on the tyrosine phosphorylation of a protein with a molecular mass of approximately 28 kD. Moreover, we demonstrated that TPO by itself was able to stimulate, at doses ranging from 0.05 to 10 ng/ml, early release and delayed synthesis of interleukin 8 (IL-8). Thus, our data indicate that, in addition to sustaining megakaryocytopoiesis, TPO may have an important role in regulating PMN activation. PMID:9120001

  13. Expression patterns of cytokines and chemokines genes in human hepatoma cells.

    PubMed

    Shin, Eui-Cheol; Choi, Youn-Hee; Kim, Ji Su; Kim, Se Jong; Park, Jeon Han

    2002-10-01

    Various cytokines and chemokines play a role in carcinogenesis. However, no study has previously been undertaken to investigate comprehensively the expressions of cytokines and chemokines in hepatoma cells. In this study, we determined which cytokines and chemokines are expressed in hepatoma cells. Recently, it was reported that the expressions of several chemokines could be increased by Fas stimulus in many normal and cancer cells. Therefore, we also investigated whether chemokines expression is regulated by Fas ligation. To address this issue, we performed RNase protection assays upon 13 cytokines and 8 chemokines genes in 10 human hepatoma cell lines, comprising 8 hepatitis B virus (HBV)-associated hepatoma cell lines. Transforming growth factor-beta2 (TGF-beta2) was found to be expressed in 8 HBV-associated hepatoma cell lines, and to be potently expressed in 5 cell lines; however, the mRNA expressions of interleukin-10 (IL-10), IL-12, interferon-gamma(IFN-gamma) and tumor necrosis factor-alpha(TNF-alpha) were not detected in any cell lines examined. Among the chemokines investigated in this study, IL-8 was expressed by 8 HBV- associated hepatoma cell lines, and monocyte chemoattractant protein-1 (MCP-1) by 7 HBV-associated hepatoma cell lines. However, the mRNA expressions of macrophage inflammatory protein-1alpha(MIP-1alpha), MIP-1beta, interferon-inducible protein-10 (IP-10), RANTES, lymphotactin and I-309 were either very weak or undetectable. Fas ligation did not increase chemokines expression in hepatoma cells. Conclusively, TGF-beta2, IL-8 and MCP-1 were overexpressed in HBV-associated hepatoma cells, and the expressions of chemokines were not increased by Fas ligation in human hepatoma cells.

  14. Redox regulation of methionine aminopeptidase 2 activity.

    PubMed

    Chiu, Joyce; Wong, Jason W H; Hogg, Philip J

    2014-05-23

    Protein translation is initiated with methionine in eukaryotes, and the majority of proteins have their N-terminal methionine removed by methionine aminopeptidases (MetAP1 and MetAP2) prior to action. Methionine removal can be important for protein function, localization, or stability. No mechanism of regulation of MetAP activity has been identified. MetAP2, but not MetAP1, contains a single Cys(228)-Cys(448) disulfide bond that has an -RHStaple configuration and links two β-loop structures, which are hallmarks of allosteric disulfide bonds. From analysis of crystal structures and using mass spectrometry and activity assays, we found that the disulfide bond exists in oxidized and reduced states in the recombinant enzyme. The disulfide has a standard redox potential of -261 mV and is efficiently reduced by the protein reductant, thioredoxin, with a rate constant of 16,180 m(-1) s(-1). The MetAP2 disulfide bond also exists in oxidized and reduced states in glioblastoma tumor cells, and stressing the cells by oxygen or glucose deprivation results in more oxidized enzyme. The Cys(228)-Cys(448) disulfide is at the rim of the active site and is only three residues distant from the catalytic His(231), which suggested that cleavage of the bond would influence substrate hydrolysis. Indeed, oxidized and reduced isoforms have different catalytic efficiencies for hydrolysis of MetAP2 peptide substrates. These findings indicate that MetAP2 is post-translationally regulated by an allosteric disulfide bond, which controls substrate specificity and catalytic efficiency.

  15. The chemokine SDF-1 activates the integrins LFA-1, VLA-4, and VLA-5 on immature human CD34(+) cells: role in transendothelial/stromal migration and engraftment of NOD/SCID mice.

    PubMed

    Peled, A; Kollet, O; Ponomaryov, T; Petit, I; Franitza, S; Grabovsky, V; Slav, M M; Nagler, A; Lider, O; Alon, R; Zipori, D; Lapidot, T

    2000-06-01

    Hematopoietic stem cell homing and engraftment require several adhesion interactions, which are not fully understood. Engraftment of nonobese/severe combined immunodeficiency (NOD/SCID) mice by human stem cells is dependent on the major integrins very late activation antigen-4 (VLA-4); VLA-5; and to a lesser degree, lymphocyte function associated antigen-1 (LFA-1). Treatment of human CD34(+) cells with antibodies to either VLA-4 or VLA-5 prevented engraftment, and treatment with anti-LFA-1 antibodies significantly reduced the levels of engraftment. Activation of CD34(+) cells, which bear the chemokine receptor CXCR4, with stromal derived factor 1 (SDF-1) led to firm adhesion and transendothelial migration, which was dependent on LFA-1/ICAM-1 (intracellular adhesion molecule-1) and VLA-4/VCAM-1 (vascular adhesion molecule-1). Furthermore, SDF-1-induced polarization and extravasation of CD34(+)/CXCR4(+) cells through the extracellular matrix underlining the endothelium was dependent on both VLA-4 and VLA-5. Our results demonstrate that repopulating human stem cells functionally express LFA-1, VLA-4, and VLA-5. Furthermore, this study implies a novel approach to further advance clinical transplantation. PMID:10828007

  16. Synthesis of some CC chemokines and their receptors in the synovium in rheumatoid arthritis.

    PubMed

    Zhebrun, D A; Totolyan, Areg A; Maslyanskii, A L; Titov, A G; Patrukhin, A P; Kostareva, A A; Gol'tseva, I S

    2014-12-01

    We studied the expression of some CC chemokines and their receptors in the synovium of patients with rheumatoid arthritis, osteoarthrosis, and a history of joint injury. In patients with rheumatoid arthritis, the levels mRNA for some angiogenic and proinflammatory chemokines (CCL5/RANTES, CCL11/eotaxin, CCL24/eotaxin-2, and CCL26/eotaxin-3) and their receptors (CCR1, CCR2, CCR3, CCR4, and CCR5) was elevated. mRNA expression correlated with activity, stage, and serological status of rheumatoid arthritis. Obtained data confirm the importance of CC chemokines as mediators of angiogenesis and inflammation in the synovium in rheumatoid arthritis.

  17. Endoglin regulates cyclooxygenase-2 expression and activity.

    PubMed

    Jerkic, Mirjana; Rivas-Elena, Juan V; Santibanez, Juan F; Prieto, Marta; Rodríguez-Barbero, Alicia; Perez-Barriocanal, Fernando; Pericacho, Miguel; Arévalo, Miguel; Vary, Calvin P H; Letarte, Michelle; Bernabeu, Carmelo; López-Novoa, Jose M

    2006-08-01

    The endoglin heterozygous (Eng(+/-)) mouse, which serves as a model of hereditary hemorrhagic telangiectasia (HHT), was shown to express reduced levels of endothelial NO synthase (eNOS) with impaired activity. Because of intricate changes in vasomotor function in the Eng(+/-) mice and the potential interactions between the NO- and prostaglandin-producing pathways, we assessed the expression and function of cyclooxygenase (COX) isoforms. A specific upregulation of COX-2 in the vascular endothelium and increased urinary excretion of prostaglandin E(2) were observed in the Eng(+/-) mice. Specific COX-2 inhibition with parecoxib transiently increased arterial pressure in Eng(+/-) but not in Eng(+/+) mice. Transfection of endoglin in L6E9 myoblasts, shown previously to stimulate eNOS expression, led to downregulation of COX-2 with no change in COX-1. In addition, COX-2 promoter activity and protein levels were inversely correlated with endoglin levels, in doxycyclin-inducible endothelial cells. Chronic NO synthesis inhibition with N(omega)-nitro-l-arginine methyl ester induced a marked increase in COX-2 only in the normal Eng(+/+) mice. N(omega)-nitro-l-arginine methyl ester also increased COX-2 expression and promoter activity in doxycyclin-inducible endoglin expressing endothelial cells, but not in control cells. The level of COX-2 expression following transforming growth factor-beta1 treatment was less in endoglin than in mock transfected L6E9 myoblasts and was higher in human endothelial cells silenced for endoglin expression. Our results indicate that endoglin is involved in the regulation of COX-2 activity. Furthermore, reduced endoglin levels and associated impaired NO production may be responsible, at least in part, for augmented COX-2 expression and activity in the Eng(+/-) mice. PMID:16840721

  18. Cxc Chemokine Receptor 5 Expression Defines Follicular Homing T Cells with B Cell Helper Function

    PubMed Central

    Schaerli, Patrick; Willimann, Katharina; Lang, Alois B.; Lipp, Martin; Loetscher, Pius; Moser, Bernhard

    2000-01-01

    Leukocyte traffic through secondary lymphoid tissues is finely tuned by chemokines. We have studied the functional properties of a human T cell subset marked by the expression of CXC chemokine receptor 5 (CXCR5). Memory but not naive T cells from tonsils are CXCR5+ and migrate in response to the B cell–attracting chemokine 1 (BCA-1), which is selectively expressed by reticular cells and blood vessels within B cell follicles. Tonsillar CXCR5+ T cells do not respond to other chemokines present in secondary lymphoid tissues, including secondary lymphoid tissue chemokine (SLC), EBV-induced molecule 1 ligand chemokine (ELC), and stromal cell–derived factor 1 (SDF-1). The involvement of tonsillar CXCR5+ T cells in humoral immune responses is suggested by their localization in the mantle and light zone germinal centers of B cell follicles and by the concomitant expression of activation and costimulatory markers, including CD69, HLA-DR, and inducible costimulator (ICOS). Peripheral blood CXCR5+ T cells also belong to the CD4+ memory T cell subset but, in contrast to tonsillar cells, are in a resting state and migrate weakly to chemokines. CXCR5+ T cells are very inefficient in the production of cytokines but potently induce antibody production during coculture with B cells. These properties portray CXCR5+ T cells as a distinct memory T cell subset with B cell helper function, designated here as follicular B helper T cells (TFH). PMID:11104798

  19. Expression patterns of chemokine receptors on circulating T cells from myelodysplastic syndrome patients.

    PubMed

    Sand, Kristoffer Evebø; Rye, Kristin Paulsen; Mannsåker, Bård; Bruserud, Oystein; Kittang, Astrid Olsnes

    2013-02-01

    Chemokines and their receptors are involved in the recruitment of leukocytes to sites of inflammation. Recently, chemokine expression signatures have been reported to convey a prognostic value in myelodysplastic syndrome (MDS) patients. In the present study, we investigated the chemokine receptor repertoire on fresh peripheral blood lymphocytes from 31 (22 low-risk and 9 high-risk) patients affected by MDS. Chemokine receptor expression was studied in defined T-cell subsets using eight-color flow cytometry. MDS patients exhibited quantitative differences in peripheral lymphocyte subpopulations. In addition, T cells obtained from MDS patients expressed a chemokine receptor pattern suggesting a dominance of mature and activated T cells. This is illustrated by increased levels of CCR3, CCR5, CX3CR1 and/or by a decreased abundance of CCR7 in defined T-cell subsets. The T-cell subset distribution appears to differ between the peripheral blood and the bone marrow of MDS patients, suggesting a preferential recruitment of specific T-cell subsets to the latter compartment. Alteration in chemokine receptor expression can develop over time even in patients that are considered clinically stable. Elevated expression levels of CXCR4 by CD8(+) cells were associated with prolonged patient survival and reduced numbers of bone marrow blasts. We conclude that immunological abnormalities in MDS also involve chemokine receptors on different subsets of T cells, and that these changes may have a prognostic value.

  20. Alantolactone from Saussurea lappa Exerts Antiinflammatory Effects by Inhibiting Chemokine Production and STAT1 Phosphorylation in TNF-α and IFN-γ-induced in HaCaT cells.

    PubMed

    Lim, Hye-Sun; Jin, Sung-Eun; Kim, Ohn-Soon; Shin, Hyeun-Kyoo; Jeong, Soo-Jin

    2015-07-01

    Skin inflammation is the most common condition seen in dermatology practice and can be caused by various allergic reactions and certain toxins or chemicals. In the present study, we investigated the antiinflammatory effects of Saussurea lappa, a medicinal herb, and its marker compounds alantolactone, caryophyllene, costic acid, costunolide, and dehydrocostuslactone in the HaCaT human keratinocyte cell line. HaCaT cells were stimulated with tumor necrosis factor-alpha (TNF-α) and interferon-gamma (IFN-γ), and treated with S. lappa or each of five marker compounds. Chemokine production and expression were analyzed by enzyme-linked immunosorbent assay and reverse transcription-polymerase chain reaction, respectively. Phosphorylation of signal transducer and activator of transcription (STAT) 1 was determined by immunoblotting. Stimulation with TNF-α and IFN-γ significantly increased the production of the following chemokines: thymus-regulated and activation-regulated chemokine (TARC): regulated on activation, normal T-cell expressed and secreted (RANTES): macrophage-derived chemokine (MDC): and interleukin-8 (IL-8). By contrast, S. lappa and the five marker compounds significantly reduced the production of these chemokines by TNF-α and IFN-γ-treated cells. S. lappa and alantolactone suppressed the TNF-α and IFN-γ-stimulated increase in the phosphorylation of STAT1. Our results demonstrate that alantolactone from S. lappa suppresses TNF-α and IFN-γ-induced production of RANTES and IL-8 by blocking STAT1 phosphorylation in HaCaT cells. PMID:25881570

  1. Performance Status in Elderly Patients With Acute Myeloid Leukemia: Exploring Gene Expression Signatures of Cytokines and Chemokines

    PubMed Central

    Nipp, Ryan D.

    2015-01-01

    Acute myeloid leukemia (AML) is an aggressive disease that predominantly affects elderly patients. Cytokines and chemokines are major players in the pathogenesis of AML. They regulate the disease course and play a deleterious role in the progression of AML. The geriatric population is particularly vulnerable to these mediators as these cytokines and chemokines are also implicated in the development of frailty, fatigue, and declining cognitive function. It is the combination of these adverse effects of cytokines and chemokines that affect performance status and, in turn, the poor prognosis in this age group. Cytokines and chemokines are emerging as therapeutic targets in AML. Future endeavors to treat AML will likely involve cytokines and chemokines as attempts are made to disrupt the bone marrow environment. By modulating the bone marrow stroma, the goal is to create an environment less favorable to AML cells and more favorable to the effects of chemotherapy against AML. PMID:23783402

  2. Induction of intercellular adhesion molecule-1 on human brain endothelial cells by HIV-1 gp120: role of CD4 and chemokine coreceptors.

    PubMed

    Stins, Monique F; Pearce, Donna; Di Cello, Francescopaolo; Erdreich-Epstein, Anat; Pardo, Carlos A; Sik Kim, Kwang

    2003-12-01

    Central nervous system dysfunction is commonly observed in children with HIV-1 infection, but the mechanisms whereby HIV-1 causes encephalopathy are not completely understood. We have previously shown that human brain microvascular endothelial cells (HBMEC) from children are responsive to gp120 derived from X4 HIV-1 by increasing expression of intercellular adhesion molecule (ICAM)-1 and vascular cell adhesion molecule-1. However, the mechanisms involved in gp120-mediated up-regulation of cell adhesion molecule expression is unclear. In the present study, we found that gp120 derived from both X4 and R5 HIV-1 induced increased expression of ICAM-1 on HBMEC, but the degree of this up-regulation differed among the various HBMEC isolates. The up-regulation of ICAM-1 was inhibited by anti-CD4 antibodies as well as by specific antibodies directed against chemokine receptors and small-molecule coreceptor inhibitors. Anti-CD4 antibodies inhibited the increase in ICAM-1 expression mediated by gp120 derived from X4 and R5 HIV-1, whereas antibodies against chemokine receptors displayed a differential inhibition depending on the source of gp120. Both X4 and R5 gp120-induced ICAM-1 expression was sensitive to pertussis toxin and involved the nuclear factor-kB pathway. These findings indicate a direct involvement of CD4 and a differential involvement of chemokine receptors in the activation of pediatric HBMEC by X4 and R5 gp120. The activation of brain endothelium of children by HIV-1 protein gp120 by way of CD4 and chemokine receptors may have implications for the pathogenesis of HIV-1 encephalopathy in the pediatric population.

  3. Serum levels of the homeostatic B cell chemokine, CXCL13, are elevated during HIV infection.

    PubMed

    Widney, Daniel P; Breen, Elizabeth C; Boscardin, W John; Kitchen, Scott G; Alcantar, Juan M; Smith, Jeffrey B; Zack, Jerome A; Detels, Roger; Martínez-Maza, Otoniel

    2005-11-01

    HIV infection is associated with B cell dysfunction, which includes B cell hyperactivation, hypergammaglobulinemia, impaired production of antibodies against specific antigens, and a loss of B cell memory. Because lymph node architecture is progressively destroyed during HIV infection, it is possible that normal B cell trafficking is impaired as well, which could be a cause or a result of these abnormalities. Because the homeostatic chemokine, CXCL13 (BLC, BCA-1), is a major regulator of B cell trafficking, we assessed circulating levels of this molecule in HIV infection. Serum levels of CXCL13 were seen to be progressively elevated in HIV disease. Serum levels of CXCL13 correlated strongly with those of the inflammation-associated chemokine, inducible protein-10 (IP-10), in subjects who had advanced HIV disease, and more moderately with levels of soluble CD30 (sCD30), sCD27, and sCD23. CXCL13 levels also correlated moderately with viral load and showed a significant decline after use of highly active antiretroviral treatment (HAART). Elevated levels of CXCL13 could cause impaired or altered trafficking of B cells during HIV infection and could contribute to the previously reported loss of CXCR5, the receptor for CXCL13, from the surface of circulating B cells in HIV infection. PMID:16318584

  4. The chemokine receptor CCR7 promotes mammary tumorigenesis through amplification of stem-like cells.

    PubMed

    Boyle, S T; Ingman, W V; Poltavets, V; Faulkner, J W; Whitfield, R J; McColl, S R; Kochetkova, M

    2016-01-01

    The chemokine receptor CCR7 is widely implicated in breast cancer pathobiology. Although recent reports correlated high CCR7 levels with more advanced tumor grade and poor prognosis, limited in vivo data are available regarding its specific function in mammary gland neoplasia and the underlying mechanisms involved. To address these questions we generated a bigenic mouse model of breast cancer combined with CCR7 deletion, which revealed that CCR7 ablation results in a considerable delay in tumor onset as well as significantly reduced tumor burden. Importantly, CCR7 was found to exert its function by regulating mammary cancer stem-like cells in both murine and human tumors. In vivo experiments showed that loss of CCR7 activity either through deletion or pharmacological antagonism significantly decreased functional pools of stem-like cells in mouse primary mammary tumors, providing a mechanistic explanation for the tumor-promoting role of this chemokine receptor. These data characterize the oncogenic properties of CCR7 in mammary epithelial neoplasia and point to a new route for therapeutic intervention to target evasive cancer stem cells.

  5. Vesicular Trafficking and Signaling for Cytokine and Chemokine Secretion in Mast Cells

    PubMed Central

    Blank, Ulrich; Madera-Salcedo, Iris Karina; Danelli, Luca; Claver, Julien; Tiwari, Neeraj; Sánchez-Miranda, Elizabeth; Vázquez-Victorio, Genaro; Ramírez-Valadez, Karla Alina; Macias-Silva, Marina; González-Espinosa, Claudia

    2014-01-01

    Upon activation mast cells (MCs) secrete numerous inflammatory compounds stored in their cytoplasmic secretory granules by a process called anaphylactic degranulation, which is responsible for type I hypersensitivity responses. Prestored mediators include histamine and MC proteases but also some cytokines and growth factors making them available within minutes for a maximal biological effect. Degranulation is followed by the de novo synthesis of lipid mediators such as prostaglandins and leukotrienes as well as a vast array of cytokines, chemokines, and growth factors, which are responsible for late phase inflammatory responses. While lipid mediators diffuse freely out of the cell through lipid bilayers, both anaphylactic degranulation and secretion of cytokines, chemokines, and growth factors depends on highly regulated vesicular trafficking steps that occur along the secretory pathway starting with the translocation of proteins to the endoplasmic reticulum. Vesicular trafficking in MCs also intersects with endocytic routes, notably to form specialized cytoplasmic granules called secretory lysosomes. Some of the mediators like histamine reach granules via specific vesicular monoamine transporters directly from the cytoplasm. In this review, we try to summarize the available data on granule biogenesis and signaling events that coordinate the complex steps that lead to the release of the inflammatory mediators from the various vesicular carriers in MCs. PMID:25295038

  6. Chemokines, macrophage inflammatory protein-2 and stromal cell-derived factor-1{alpha}, suppress amyloid {beta}-induced neurotoxicity

    SciTech Connect

    Raman, Dayanidhi; Milatovic, Snjezana-Zaja; Milatovic, Dejan; Fan, Guo-Huang; Richmond, Ann

    2011-11-15

    Alzheimer's disease (AD) is characterized by a progressive cognitive decline and accumulation of neurotoxic oligomeric peptides amyloid-{beta} (A{beta}). Although the molecular events are not entirely known, it has become evident that inflammation, environmental and other risk factors may play a causal, disruptive and/or protective role in the development of AD. The present study investigated the ability of the chemokines, macrophage inflammatory protein-2 (MIP-2) and stromal cell-derived factor-1{alpha} (SDF-1{alpha}), the respective ligands for chemokine receptors CXCR2 and CXCR4, to suppress A{beta}-induced neurotoxicity in vitro and in vivo. Pretreatment with MIP-2 or SDF-1{alpha} significantly protected neurons from A{beta}-induced dendritic regression and apoptosis in vitro through activation of Akt, ERK1/2 and maintenance of metalloproteinase ADAM17 especially with SDF-1{alpha}. Intra-cerebroventricular (ICV) injection of A{beta} led to reduction in dendritic length and spine density of pyramidal neurons in the CA1 area of the hippocampus and increased oxidative damage 24 h following the exposure. The A{beta}-induced morphometric changes of neurons and increase in biomarkers of oxidative damage, F{sub 2}-isoprostanes, were significantly inhibited by pretreatment with the chemokines MIP-2 or SDF-1{alpha}. Additionally, MIP-2 or SDF-1{alpha} was able to suppress the aberrant mislocalization of p21-activated kinase (PAK), one of the proteins involved in the maintenance of dendritic spines. Furthermore, MIP-2 also protected neurons against A{beta} neurotoxicity in CXCR2-/- mice, potentially through observed up regulation of CXCR1 mRNA. Understanding the neuroprotective potential of chemokines is crucial in defining the role for their employment during the early stages of neurodegeneration. -- Research highlights: Black-Right-Pointing-Pointer Neuroprotective ability of the chemokines MIP2 and CXCL12 against A{beta} toxicity. Black-Right-Pointing-Pointer MIP-2 or

  7. Involvement of chemokine receptors in breast cancer metastasis

    NASA Astrophysics Data System (ADS)

    Müller, Anja; Homey, Bernhard; Soto, Hortensia; Ge, Nianfeng; Catron, Daniel; Buchanan, Matthew E.; McClanahan, Terri; Murphy, Erin; Yuan, Wei; Wagner, Stephan N.; Barrera, Jose Luis; Mohar, Alejandro; Verástegui, Emma; Zlotnik, Albert

    2001-03-01

    Breast cancer is characterized by a distinct metastatic pattern involving the regional lymph nodes, bone marrow, lung and liver. Tumour cell migration and metastasis share many similarities with leukocyte trafficking, which is critically regulated by chemokines and their receptors. Here we report that the chemokine receptors CXCR4 and CCR7 are highly expressed in human breast cancer cells, malignant breast tumours and metastases. Their respective ligands CXCL12/SDF-1α and CCL21/6Ckine exhibit peak levels of expression in organs representing the first destinations of breast cancer metastasis. In breast cancer cells, signalling through CXCR4 or CCR7 mediates actin polymerization and pseudopodia formation, and subsequently induces chemotactic and invasive responses. In vivo, neutralizing the interactions of CXCL12/CXCR4 significantly impairs metastasis of breast cancer cells to regional lymph nodes and lung. Malignant melanoma, which has a similar metastatic pattern as breast cancer but also a high incidence of skin metastases, shows high expression levels of CCR10 in addition to CXCR4 and CCR7. Our findings indicate that chemokines and their receptors have a critical role in determining the metastatic destination of tumour cells.

  8. Substance P primes lipoteichoic acid- and Pam3CysSerLys4-mediated activation of human mast cells by up-regulating Toll-like receptor 2.

    PubMed

    Tancowny, Brian P; Karpov, Victor; Schleimer, Robert P; Kulka, Marianna

    2010-10-01

    Substance P (SP) is a neuropeptide with neuroimmunoregulatory activity that may play a role in susceptibility to infection. Human mast cells, which are important in innate immune responses, were analysed for their responses to pathogen-associated molecules via Toll-like receptors (TLRs) in the presence of SP. Human cultured mast cells (LAD2) were activated by SP and TLR ligands including lipopolysaccharide (LPS), Pam3CysSerLys4 (Pam3CSK4) and lipoteichoic acid (LTA), and mast cell leukotriene and chemokine production was assessed by enzyme-linked immunosorbent assay (ELISA) and gene expression by quantitative PCR (qPCR). Mast cell degranulation was determined using a β-hexosaminidase (β-hex) assay. SP treatment of LAD2 up-regulated mRNA for TLR2, TLR4, TLR8 and TLR9 while anti-immunoglobulin E (IgE) stimulation up-regulated expression of TLR4 only. Flow cytometry and western blot confirmed up-regulation of TLR2 and TLR8. Pretreatment of LAD2 with SP followed by stimulation with Pam3CSK4 or LTA increased production of leukotriene C4 (LTC(4) ) and interleukin (IL)-8 compared with treatment with Pam3CSK4 or LTA alone (>2-fold; P<0·01). SP alone activated 5-lipoxygenase (5-LO) nuclear translocation but also augmented Pam3CSK4 and LTA-mediated 5-LO translocation. Pam3CSK4, LPS and LTA did not induce LAD2 degranulation. SP primed LTA and Pam3CSK4-mediated activation of JNK, p38 and extracellular-signal-regulated kinase (ERK) and activated the nuclear translocation of c-Jun, nuclear factor (NF)-κB, activating transcription factor 2 (ATF-2) and cyclic-AMP-responsive element binding protein (CREB) transcription factors. Pretreatment with SP followed by LTA stimulation synergistically induced production of chemokine (C-X-C motif) ligand 8 (CXCL8)/IL-8, chemokine (C-C motif) ligand 2 (CCL2)/monocyte chemotactic protein 1 (MCP-1), tumour necrosis factor (TNF) and IL-6 protein. SP primes TLR2-mediated activation of human mast cells by up-regulating TLR expression and

  9. Cyfip1 Regulates Presynaptic Activity during Development

    PubMed Central

    Hsiao, Kuangfu; Harony-Nicolas, Hala; Buxbaum, Joseph D.

    2016-01-01

    Copy number variations encompassing the gene encoding Cyfip1 have been associated with a variety of human diseases, including autism and schizophrenia. Here we show that juvenile mice hemizygous for Cyfip1 have altered presynaptic function, enhanced protein translation, and increased levels of F-actin. In developing hippocampus, reduced Cyfip1 levels serve to decrease paired pulse facilitation and increase miniature EPSC frequency without a change in amplitude. Higher-resolution examination shows these changes to be caused primarily by an increase in presynaptic terminal size and enhanced vesicle release probability. Short hairpin-mediated knockdown of Cyfip1 coupled with expression of mutant Cyfip1 proteins indicates that the presynaptic alterations are caused by dysregulation of the WAVE regulatory complex. Such dysregulation occurs downstream of Rac1 as acute exposure to Rac1 inhibitors rescues presynaptic responses in culture and in hippocampal slices. The data serve to highlight an early and essential role for Cyfip1 in the generation of normally functioning synapses and suggest a means by which changes in Cyfip1 levels could impact the generation of neural networks and contribute to abnormal and maladaptive behaviors. SIGNIFICANCE STATEMENT Several developmental brain disorders have been associated with gene duplications and deletions that serve to increase or decrease levels of encoded proteins. Cyfip1 is one such protein, but the role it plays in brain development is poorly understood. We asked whether decreased Cyfip1 levels altered the function of developing synapses. The data show that synapses with reduced Cyfip1 are larger and release neurotransmitter more rapidly. These effects are due to Cyfip1's role in actin polymerization and are reversed by expression of a Cyfip1 mutant protein retaining actin regulatory function or by inhibiting Rac1. Thus, Cyfip1 has a more prominent early role regulating presynaptic activity during a stage of development when

  10. Activity and Regulation of Archaeal DNA Alkyltransferase

    PubMed Central

    Perugino, Giuseppe; Vettone, Antonella; Illiano, Giuseppina; Valenti, Anna; Ferrara, Maria C.; Rossi, Mosè; Ciaramella, Maria

    2012-01-01

    Agents that form methylation adducts in DNA are highly mutagenic and carcinogenic, and organisms have evolved specialized cellular pathways devoted to their repair, including DNA alkyltransferases. These are proteins conserved in eucarya, bacteria and archaea, acting by a unique reaction mechanism, which leads to direct repair of DNA alkylation damage and irreversible protein alkylation. The alkylated form of DNA alkyltransferases is inactive, and in eukaryotes, it is rapidly directed to degradation. We report here in vitro and in vivo studies on the DNA alkyltransferase from the thermophilic archaeon Sulfolobus solfataricus (SsOGT). The development of a novel, simple, and sensitive fluorescence-based assay allowed a careful characterization of the SsOGT biochemical and DNA binding activities. In addition, transcriptional and post-translational regulation of SsOGT by DNA damage was studied. We show that although the gene transcription is induced by alkylating agent treatment, the protein is degraded in vivo by an alkylation-dependent mechanism. These experiments suggest a striking conservation, from archaea to humans, of this important pathway safeguarding genome stability. PMID:22167184

  11. 76 FR 12364 - Agency Information Collection Activities: Bonded Warehouse Regulations

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-03-07

    ... SECURITY U.S. Customs and Border Protection Agency Information Collection Activities: Bonded Warehouse... Bonded Warehouse Regulations. This request for comment is being made pursuant to the Paperwork Reduction... concerning the following information collection: Title: Bonded Warehouse Regulations. OMB Number:...

  12. CXC chemokine signaling in the liver: Impact on repair and regeneration

    PubMed Central

    Van Sweringen, Heather L.; Sakai, Nozomu; Tevar, Amit D.; Burns, Justin M.; Edwards, Michael J.; Lentsch, Alex B.

    2011-01-01

    The process of liver repair and regeneration following hepatic injury is complex and relies on a temporally coordinated integration of several key signaling pathways. Pathways activated by members of the CXC family of chemokines play important roles in the mechanisms of liver repair and regeneration through their effects on hepatocytes. However, little is known about the signaling pathways utilized by CXC chemokine receptors in hepatocytes. Here we review our current understanding of the pathways involved in both CXC chemokine receptor signaling in other cell types, most notably neutrophils, and similar pathways operant during hepatocyte proliferation/liver regeneration in order to formulate a basis for the function of CXC chemokine receptor signaling in hepatocytes. PMID:21626524

  13. Extracellular Nucleotides Can Induce Chemokine (C-C motif) Ligand 2 Expression in Human Vascular Smooth Muscle Cells

    PubMed Central

    Kim, Jeung-Il; Kim, Hye-Young; Kim, Sun-Mi; Lee, Sae-A; Son, Yong-Hae; Eo, Seong-Kug; Rhim, Byung-Yong

    2011-01-01

    To understand the roles of purinergic receptors and cellular molecules below the receptors in the vascular inflammatory response, we determined if extracellular nucleotides up-regulated chemokine expression in vascular smooth muscle cells (VSMCs). Human aortic smooth muscle cells (AoSMCs) abundantly express P2Y1, P2Y6, and P2Y11 receptors, which all respond to extracellular nucleotides. Exposure of human AoSMCs to NAD+, an agonist of the human P2Y11 receptor, and NADP+ as well as ATP, an agonist for P2Y1 and P2Y11 receptors, caused increase in chemokine (C-C motif) ligand 2 gene (CCL2) transcript and CCL2 release; however, UPT did not affect CCL2 expression. CCL2 release by NAD+ and NADP+ was inhibited by a concentration dependent manner by suramin, an antagonist of P2-purinergic receptors. NAD+ and NADP+ activated protein kinase C and enhanced phosphorylation of mitogen-activated protein kinases and Akt. NAD+- and NADP+-mediated CCL2 release was significantly attenuated by SP6001250, U0126, LY294002, Akt inhibitor IV, RO318220, GF109203X, and diphenyleneiodium chloride. These results indicate that extracellular nucleotides can promote the proinflammatory VSMC phenotype by up-regulating CCL2 expression, and that multiple cellular elements, including phosphatidylinositol 3-kinase, Akt, protein kinase C, and mitogen-activated protein kinases, are involved in that process. PMID:21461238

  14. Cytokines, Chemokines, and Chemokine Receptors Quantitative Expressions in Patients with Ovarian Cancer

    PubMed Central

    Rezaeifard, Somayeh; Razmkhah, Mahboobeh; Robati, Minoo; Momtahan, Mozhdeh; Ghaderi, Abbas

    2015-01-01

    Background Cytokines, chemokines, and chemokine receptors regulate the proliferation and survival of tumor cells, angiogenesis, and metastasis to other organs. This network of ligands and receptors has been used in molecular targeting of cancer. Methods We compared the mRNA expression of CXCR3, CXCL-10, CXCR4, CXCL-12, IL-4, and IL-10 in tissues of benign and malignant ovarian tumors by qRT-PCR method and evaluated serum IL-10 and CA-125 content of these patients by ELISA during one year. Results Our result showed a trend toward a higher expression of CXCR4 in malignant ovarian tissues compared with the benign ovarian cysts (P>0.05). However, SDF-1, IP-10, IL-4, CXCR3, and IL-10 had a lower trend in mRNA expression in malignant ovarian tissues compared to the benign cyst tissues. Except for IL-4 (P=0.01) and SDF-1 (P=0.02), the data for other factors were not statistically significant. A trend toward higher concentration of IL-10 was observed in the serum of ovarian cancer patients compared to those with benign cysts; however, the difference was not significant. CA-125 concentration in the serum of ovarian cancer patients was higher than that of benign cyst patients (P=0.05). Conclusion According to results obtained, we hypothesize that the lower expression of SDF-1 in malignant tissues may have an important role in ovarian tumor growth. However, this hypothesis requires more investigation. Higher levels of CA125 and IL-10 in the serum of patients might indicate that the combination of these biomarkers could be used for distinguishing patients with ovarian cancer from those with benign cysts.   PMID:25999622

  15. Interference with glycosaminoglycan-chemokine interactions with a probe to alter leukocyte recruitment and inflammation in vivo.

    PubMed

    Li, Sandra; Pettersson, Ulrika S; Hoorelbeke, Bart; Kolaczkowska, Elzbieta; Schelfhout, Katrien; Martens, Erik; Kubes, Paul; Van Damme, Jo; Phillipson, Mia; Opdenakker, Ghislain

    2014-01-01

    In vivo leukocyte recruitment is not fully understood and may result from interactions of chemokines with glycosaminoglycans/GAGs. We previously showed that chlorite-oxidized oxyamylose/COAM binds the neutrophil chemokine GCP-2/CXCL6. Here, mouse chemokine binding by COAM was studied systematically and binding affinities of chemokines to COAM versus GAGs were compared. COAM and heparan sulphate bound the mouse CXC chemokines KC/CXCL1, MIP-2/CXCL2, IP-10/CXCL10 and I-TAC/CXCL11 and the CC chemokine RANTES/CCL5 with affinities in the nanomolar range, whereas no binding interactions were observed for mouse MCP-1/CCL2, MIP-1α/CCL3 and MIP-1β/CCL4. The affinities of COAM-interacting chemokines were similar to or higher than those observed for heparan sulphate. Although COAM did not display chemotactic activity by itself, its co-administration with mouse GCP-2/CXCL6 and MIP-2/CXCL2 or its binding of endogenous chemokines resulted in fast and cooperative peritoneal neutrophil recruitment and in extravasation into the cremaster muscle in vivo. These local GAG mimetic features by COAM within tissues superseded systemic effects and were sufficient and applicable to reduce LPS-induced liver-specific neutrophil recruitment and activation. COAM mimics glycosaminoglycans and is a nontoxic probe for the study of leukocyte recruitment and inflammation in vivo. PMID:25093679

  16. Heterologous Quaternary Structure of CXCL12 and its Relationship to the CC Chemokine Family

    SciTech Connect

    Murphy, J.; Yuan, H; Kong, Y; Xiong, Y; Lolis, E

    2010-01-01

    X-ray crystallographic studies reveal that CXCL12 is able to form multiple dimer types, a traditional CXC dimer and a 'CC-like' form. Phylogenetic analysis of all known human chemokines demonstrates CXCL12 is more closely related to the CC chemokine class than other CXC chemokines. These observations indicate that CXCL12 contains genomic and structural elements characteristic of both CXC and CC chemokines.Chemokines are members of a superfamily of proteins involved in the migration of cells to the proper anatomical position during embryonic development or in response to infection or stress during an immune response. There are two major (CC and CXC) and two minor (CX3C and XC) families based on the sequence around the first conserved cysteine. The topology of all structures is essentially identical with a flexible N-terminal region of 3-8 amino acids, a 10-20 residue N-terminal loop, a short 3{sub 10}-helix, three {beta}-strands, and a {alpha}-helix. The major consequence of the subtle difference between the families occurs at the oligomeric level. Monomers of the CC, CXC, and CX3C families form dimers in a family-specific manner. The XCL1 chemokine is a monomer that can interconvert between two folded states. All chemokines activate GPCRs according to family-specificity, however there are a few examples of chemokines crossing the family boundary to function as antagonists. A two-stage mechanism for chemokine activation of GPCRs has been proposed. The N-terminal region of the receptor interacts with the chemokine, followed by receptor activation by the chemokine N-terminal region. Monomeric chemokines have been demonstrated to be the active form for receptor function. There are numerous examples of both chemokines and their receptors forming dimers. While family-specific dimerization may be an attractive explanation for why specific chemokines only activate GPCRs within their own family, the role of dimers in the function of chemokines has not been resolved. Given

  17. CC and CXC chemokines are pivotal mediators of cerebral injury in ischaemic stroke.

    PubMed

    Mirabelli-Badenier, Marisol; Braunersreuther, Vincent; Viviani, Giorgio Luciano; Dallegri, Franco; Quercioli, Alessandra; Veneselli, Edvige; Mach, François; Montecucco, Fabrizio

    2011-03-01

    The definition of ischaemic stroke has been recently updated as an acute episode of neurological dysfunction caused by focal brain, spinal cord, or retinal ischaemia in the presence of a cerebral infarction. This "tissular" definition has highlighted the importance of pathophysiological processes underlying cerebral damage. In particular, post- ischaemic inflammation in the brain and in the blood stream could influence crucial steps of the tissue injury/repair cascade. CC and CXC chemokines orchestrate the inflammatory response in atherosclerotic plaque vulnerability and cerebral infarction. These molecules exert their activities through the binding to selective transmembrane receptors. CC and CXC chemokines modulate crucial processes (such as inflammatory cell recruitment and activation, neuronal survival, neoangiogenesis). On the other hand, CXC chemokines could also modulate stem cell homing, thus favouring tissue repair. Given this evidence, both CC and CXC chemokines could represent promising therapeutic targets in primary and secondary prevention of ischaemic stroke. Only preliminary studies have been performed investigating treatments with selective chemokine agonists/antagonists. In this review, we will update evidence on the role and the potential therapeutic strategies targeting CC and CXC chemokines in the pathophysiology of ischaemic stroke. PMID:21174009

  18. Interferons Induce CXCR3-cognate Chemokine Production by Human Metastatic Melanoma

    PubMed Central

    Dengel, Lynn T.; Norrod, Allison G.; Gregory, Briana L.; Clancy-Thompson, Eleanor; Burdick, Marie D.; Strieter, Robert M.; Slingluff, Craig L.; Mullins, David W.

    2010-01-01

    Immune-mediated cancer regression requires tumor infiltration by Ag-specific effector T cells, but lymphocytes are commonly sparse in melanoma metastases. Activated T cells express CXCR3, whose cognate chemokines are CXCL9/MIG, CXCL10/IP-10 and CXCL11/I-TAC. Little is known about expression of these chemokines in lymph node (LN) metastases of melanoma. We evaluated whether metastatic melanoma induces these CXCR3-cognate chemokines in human LN-derived tissues. Also, because these chemokines can be induced by interferon (IFN), we evaluated whether type I or II IFNs (IFN-α or IFN-γ, respectively) can modulate chemokine expression in an in vitro model of the human tumor microenvironment. Production of CXCL9-11 by melanoma-infiltrated nodes (MIN) was no different than tumor-free nodes (TFN); both produced less chemokine than activated LN (sentinel immunized nodes, SIN). These data suggest melanoma infiltration into LN neither induces nor reduces CXCL9-11. Stimulation with IFN-α or IFN-γ increased production of CXCL10-11 from MIN, but not TFN or SIN. IFN-γ also increased production of CXCL9 in MIN. In IFN-treated SIN, CD14+ cells were the primary source of CXCL9-11, whereas melanoma cells were the source of chemokine in MIN. Melanoma cells in MIN express IFN receptors. Consistent with these observations, multiple human melanoma lines expressed IFN receptors and produced CXCL9-11 in response to IFN treatment. Thus, melanoma infiltration of LN is insufficient to induce the production of CXCL9-11, but melanoma may be a significant source of IFN-induced chemokines. Collectively, these data suggest that IFN-α or IFN-γ may act in the tumor microenvironment to increase the chemotactic gradient for CXCR3+ T cells. PMID:20948440

  19. Dynamics and thermodynamic properties of CXCL7 chemokine.

    PubMed

    Herring, Charles A; Singer, Christopher M; Ermakova, Elena A; Khairutdinov, Bulat I; Zuev, Yuriy F; Jacobs, Donald J; Nesmelova, Irina V

    2015-11-01

    Chemokines form a family of signaling proteins mainly responsible for directing the traffic of leukocytes, where their biological activity can be modulated by their oligomerization state. We characterize the dynamics and thermodynamic stability of monomer and homodimer structures of CXCL7, one of the most abundant platelet chemokines, using experimental methods that include circular dichroism (CD) and nuclear magnetic resonance (NMR) spectroscopy, and computational methods that include the anisotropic network model (ANM), molecular dynamics (MD) simulations and the distance constraint model (DCM). A consistent picture emerges for the effects of dimerization and Cys5-Cys31 and Cys7-Cys47 disulfide bonds formation. The presence of disulfide bonds is not critical for maintaining structural stability in the monomer or dimer, but the monomer is destabilized more than the dimer upon removal of disulfide bonds. Disulfide bonds play a key role in shaping the characteristics of native state dynamics. The combined analysis shows that upon dimerization flexibly correlated motions are induced between the 30s and 50s loop within each monomer and across the dimer interface. Interestingly, the greatest gain in flexibility upon dimerization occurs when both disulfide bonds are present, and the homodimer is least stable relative to its two monomers. These results suggest that the highly conserved disulfide bonds in chemokines facilitate a structural mechanism that is tuned to optimally distinguish functional characteristics between monomer and dimer. PMID:26297927

  20. Chemokine Function in Periodontal Disease and Oral Cavity Cancer

    PubMed Central

    Sahingur, Sinem Esra; Yeudall, W. Andrew

    2015-01-01

    The chemotactic cytokines, or chemokines, comprise a superfamily of polypeptides with a wide range of activities that include recruitment of immune cells to sites of infection and inflammation, as well as stimulation of cell proliferation. As such, they function as antimicrobial molecules and play a central role in host defenses against pathogen challenge. However, their ability to recruit leukocytes and potentiate or prolong the inflammatory response may have profound implications for the progression of oral diseases such as chronic periodontitis, where tissue destruction may be widespread. Moreover, it is increasingly recognized that chronic inflammation is a key component of tumor progression. Interaction between cancer cells and their microenvironment is mediated in large part by secreted factors such as chemokines, and serves to enhance the malignant phenotype in oral and other cancers. In this article, we will outline the biological and biochemical mechanisms of chemokine action in host–microbiome interactions in periodontal disease and in oral cancer, and how these may overlap and contribute to pathogenesis. PMID:25999952

  1. Microbial corruption of the chemokine system: an expanding paradigm.

    PubMed

    Pease, J E; Murphy, P M

    1998-06-01

    The chemokine signaling system includes more than 40 secreted pro-inflammatory peptides and 12 G protein-coupled receptors that together orchestrate specific leukocyte trafficking in the mammalian immune system, ideally for anti- microbial defense and tissue repair processes. Paradoxically and perversely, some chemokines and chemokine receptors are also promicrobial factors and facilitate infectious disease, the result of either exploitation or subversion by specific microbes. Two modes of exploitation are known: usage of cellular chemokine receptors for cell entry by intracellular pathogens, including HIV, and usage of virally-encoded chemokine receptors for host cell proliferation. Likewise, two modes of subversion are known: virally-encoded chemokine antagonists and virally-encoded chemokine scavengers. Understanding how microbes turn the tables on the chemokine system may point to new methods to prevent or treat infection, or, more generally, to treat inappropriate chemokine-mediated inflammation.

  2. Feasibility of the Use of Combinatorial Chemokine Arrays to Study Blood and CSF in Multiple Sclerosis

    PubMed Central

    Plavina, Tatiana; Czerkowicz, Julie; Goelz, Susan; Ranger, Ann; Cadavid, Diego; Browning, Jeffrey L.

    2013-01-01

    Meningeal inflammation, including the presence of semi-organized tertiary lymphoid tissue, has been associated with cortical pathology at autopsy in secondary progressive multiple sclerosis (SPMS).  Accessible and robust biochemical markers of cortical inflammation for use in SPMS clinical trials are needed.  Increased levels of chemokines in the cerebrospinal fluid (CSF) can report on inflammatory processes occurring in the cerebral cortex of MS patients.  A multiplexed chemokine array that included BAFF, a high sensitivity CXCL13 assay and composite chemokine scores were developed to explore differences in lymphoid (CXCL12, CXCL13, CCL19 and CCL21) and inflammatory (CCL2, CXCL9, CXCL10 and CXCL11) chemokines in a small pilot study.  Paired CSF and serum samples were obtained from healthy controls (n=12), relapsing-remitting MS (RRMS) (n=21) and SPMS (N=12). A subset of the RRMS patients (n = 9) was assessed upon disease exacerbation and 1 month later following iv methylprednisone. SPMS patients were sampled twice to ascertain stability. Both lymphoid and inflammatory chemokines were elevated in RRMS and SPMS with the highest levels found in the active RRMS group. Inflammatory and lymphoid chemokine signatures were defined and generally correlated with each other. This small exploratory clinical study shows the feasibility of measuring complex and potentially more robust chemokine signatures in the CSF of MS patients during clinical trials. No differences were found between stable RRMS and SPMS. Future trials with larger patient cohorts with this chemokine array are needed to further characterize the differences, or the lack thereof, between stable RRMS and SPMS.    PMID:24278364

  3. A chemokine-binding domain in the tumor necrosis factor receptor from variola (smallpox) virus.

    PubMed

    Alejo, Alí; Ruiz-Argüello, M Begoña; Ho, Yin; Smith, Vincent P; Saraiva, Margarida; Alcami, Antonio

    2006-04-11

    Variola virus (VaV) is the causative agent of smallpox, one of the most devastating diseases encountered by man, that was eradicated in 1980. The deliberate release of VaV would have catastrophic consequences on global public health. However, the mechanisms that contribute to smallpox pathogenesis are poorly understood at the molecular level. The ability of viruses to evade the host defense mechanisms is an important determinant of viral pathogenesis. Here we show that the tumor necrosis factor receptor (TNFR) homologue CrmB encoded by VaV functions not only as a soluble decoy TNFR but also as a highly specific binding protein for several chemokines that mediate recruitment of immune cells to mucosal surfaces and the skin, sites of virus entry and viral replication at late stages of smallpox. CrmB binds chemokines through its C-terminal domain, which is unrelated to TNFRs, was named smallpox virus-encoded chemokine receptor (SECRET) domain and uncovers a family of poxvirus chemokine inhibitors. An active SECRET domain was found in another viral TNFR (CrmD) and three secreted proteins encoded by orthopoxviruses. These findings identify a previously undescribed chemokine-binding and inhibitory domain unrelated to host chemokine receptors and a mechanism of immune modulation in VaV that may influence smallpox pathogenesis.

  4. The {beta}-chemokines CCL2 and CCL7 are two novel differentiation factors for midbrain dopaminergic precursors and neurons

    SciTech Connect

    Edman, Linda C.; Mira, Helena; Arenas, Ernest

    2008-06-10

    {beta}-chemokines are secreted factors that regulate diverse functions in the adult brain, such as neuro-immune responses and neurotransmission, but their function in the developing brain is largely unknown. We recently found that the orphan nuclear receptor, Nurr1, up regulates CCL2 and CCL7 in neural stem cells, suggesting a possible function of {beta}-chemokines in midbrain development. Here we report that two {beta}-chemokines, CCL2 and CCL7, and two of their receptors, CCR1 and CCR2, are expressed and developmentally regulated in the ventral midbrain (VM). Moreover, we found that the expression of CCL7 was down regulated in the Nurr1 knockout mice, linking CCL7 to dopamine (DA) neuron development. When the function of CCL2 and CCL7 was examined, we found that they selectively enhanced the differentiation of Nurr1+ precursors into DA neurons, but not their survival or progenitor proliferation in primary precursor cultures. Moreover, both CCL2 and CCL7 promoted neuritogenesis in midbrain DA neuron cultures. Thus, our results show for the first time a function of {beta}-chemokines in the developing brain and identify {beta}-chemokines as novel class of pro-differentiation factors for midbrain DA neurons. These data also suggest that {beta}-chemokines may become useful tools to enhance the differentiation of DA cell preparations for cell replacement therapy and drug discovery in Parkinson's disease (PD)

  5. CCR2 chemokine receptor signaling mediates pain in experimental osteoarthritis

    PubMed Central

    Miller, Rachel E.; Tran, Phuong B.; Das, Rosalina; Ghoreishi-Haack, Nayereh; Ren, Dongjun; Miller, Richard J.; Malfait, Anne-Marie

    2012-01-01

    Osteoarthritis is one of the leading causes of chronic pain, but almost nothing is known about the mechanisms and molecules that mediate osteoarthritis-associated joint pain. Consequently, treatment options remain inadequate and joint replacement is often inevitable. Here, we use a surgical mouse model that captures the long-term progression of knee osteoarthritis to longitudinally assess pain-related behaviors and concomitant changes in the innervating dorsal root ganglia (DRG). We demonstrate that monocyte chemoattractant protein (MCP)-1 (CCL2) and its high-affinity receptor, chemokine (C-C motif) receptor 2 (CCR2), are central to the development of pain associated with knee osteoarthritis. After destabilization of the medial meniscus, mice developed early-onset secondary mechanical allodynia that was maintained for 16 wk. MCP-1 and CCR2 mRNA, protein, and signaling activity were temporarily up-regulated in the innervating DRG at 8 wk after surgery. This result correlated with the presentation of movement-provoked pain behaviors, which were maintained up to 16 wk. Mice that lack Ccr2 also developed mechanical allodynia, but this started to resolve from 8 wk onwards. Despite severe allodynia and structural knee joint damage equal to wild-type mice, Ccr2-null mice did not develop movement-provoked pain behaviors at 8 wk. In wild-type mice, macrophages infiltrated the DRG by 8 wk and this was maintained through 16 wk after surgery. In contrast, macrophage infiltration was not observed in Ccr2-null mice. These observations suggest a key role for the MCP-1/CCR2 pathway in establishing osteoarthritis pain. PMID:23185004

  6. Chemokines and chemokine receptors as novel therapeutic targets in rheumatoid arthritis (RA): inhibitory effects of traditional Chinese medicinal components.

    PubMed

    Chen, Xin; Oppenheim, Joost J; Howard, O M Zack

    2004-10-01

    Chemokines belong to a large family of inflammatory cytokines responsible for migration and accumulation of leukocytes at inflammatory sites. Over the past decade, accumulating evidence indicated a crucial role for chemokines and chemokine receptors in the pathophysiology of rheumatoid arthritis (RA). RA is a chronic autoimmune disease in which the synovial tissue is heavily infiltrated by leukocytes. Chemokines play an important role in the infiltration, localization, retention of infiltrating leukocytes and generation of ectopic germinal centers in the inflamed synovium. Recent evidence also suggests that identification of inhibitors directly targeting chemokines or their receptors may provide a novel therapeutic strategy in RA. Traditional Chinese medicines (TCMs) have a long history in the treatment of inflammatory joint disease. The basis for the clinical benefits of TCM remains largely unclear. Our studies have led to the identification of numerous novel chemokine/chemokine receptor inhibitors present in anti-inflammatory TCMs. All of these inhibitors were previously reported by other researchers to have anti-arthritic effect, which may be attributable, at least in part, to their inhibitory effect on chemokine and/or chemokine receptor. Therefore, identification of agents capable of targeting chemokine/chemokine receptor interactions has suggested a mechanism of action for several TCM components and provided a means of identifying additional anti-RA TCM. Thus, this approach may lead to the discovery of new inhibitors of chemokines or chemokine receptors that can be used to treat diseases associated with inappropriately overactive chemokine mediated inflammatory reactions.

  7. Sex Hormones' Regulation of Rodent Physical Activity: A Review

    PubMed Central

    Lightfoot, J. Timothy

    2008-01-01

    There is a large body of emerging literature suggesting that physical activity is regulated to a varying extent by biological factors. Available animal data strongly suggests that there is a differential regulation of physical activity by sex and that the majority of this differential regulation is mediated by estrogen/testosterone pathways with females in many animal species having higher daily activity levels than males. The purpose of this manuscript is to review the mechanisms by which estrogen, progesterone, and testosterone affect the regulation of physical daily activity. This review lays the foundation for future investigations in humans as well as discussions about relative disease risk mediated by differential biological regulation of physical activity by sex. PMID:18449357

  8. JAK tyrosine kinases promote hierarchical activation of Rho and Rap modules of integrin activation.

    PubMed

    Montresor, Alessio; Bolomini-Vittori, Matteo; Toffali, Lara; Rossi, Barbara; Constantin, Gabriela; Laudanna, Carlo

    2013-12-23

    Lymphocyte recruitment is regulated by signaling modules based on the activity of Rho and Rap small guanosine triphosphatases that control integrin activation by chemokines. We show that Janus kinase (JAK) protein tyrosine kinases control chemokine-induced LFA-1- and VLA-4-mediated adhesion as well as human T lymphocyte homing to secondary lymphoid organs. JAK2 and JAK3 isoforms, but not JAK1, mediate CXCL12-induced LFA-1 triggering to a high affinity state. Signal transduction analysis showed that chemokine-induced activation of the Rho module of LFA-1 affinity triggering is dependent on JAK activity, with VAV1 mediating Rho activation by JAKs in a Gαi-independent manner. Furthermore, activation of Rap1A by chemokines is also dependent on JAK2 and JAK3 activity. Importantly, activation of Rap1A by JAKs is mediated by RhoA and PLD1, thus establishing Rap1A as a downstream effector of the Rho module. Thus, JAK tyrosine kinases control integrin activation and dependent lymphocyte trafficking by bridging chemokine receptors to the concurrent and hierarchical activation of the Rho and Rap modules of integrin activation.

  9. Matrix metalloproteinases and chemokines in the gingival crevicular fluid during orthodontic tooth movement.

    PubMed

    Capelli, Jonas; Kantarci, Alpdogan; Haffajee, Anne; Teles, Ricardo Palmier; Fidel, Rivail; Figueredo, Carlos Marcelo

    2011-12-01

    Matrix metalloproteinases (MMPs) and monocyte chemoattractants are key modulators of the biological mechanisms triggered in the periodontium by mechanical forces. The gingival crevicular fluid (GCF) provides a non-invasive method to assess longitudinally the release of inflammatory mediators during orthodontic tooth movement. The goal of this study was to examine the GCF levels of MMP-3, MMP-9, and MMP-13 and of the chemokines macrophage inflammatory protein (MIP)-1β, monocyte chemoattractant protein (MCP)-1, and regulated on activation normal T cells expressed and secreted (RANTES) at different time points during orthodontic tooth movement. Fourteen subjects (three males and 11 females, 18.8 ± 4.8 years of age; range from 12 to 28 years) had their maxillary canines retracted. Thirty-second GCF samples were collected from the tension and pressure sides 7 days prior to the activation of the orthodontic appliance, on the day of activation, and after 1 and 24 hours, and 14, 21, and 80 days of constant force application. The volume of GCF was measured and samples analysed using a multiplexed bead immunoassay for the content of the six target molecules. Differences in the mean GFC volumes and mean level for each analyte over time were assessed using the Friedman test, and differences between the tension and pressure sides at each time point with the Mann-Whitney test. The mean levels of the three MMPs changed significantly over time but only at the compression side (P < 0.05, Friedman test). The GCF levels of the three chemokines were not affected by the application of mechanical stress. The levels of MMPs in GCF at the pressure side are modulated by the application of orthodontic force. PMID:21389074

  10. Requirement of the Chemokine Receptor CXCR3 for Acute Allograft Rejection

    PubMed Central

    Hancock, Wayne W.; Lu, Bao; Gao, Wei; Csizmadia, Vilmos; Faia, Kerrie; King, Jennifer A.; Smiley, Stephen T.; Ling, Mai; Gerard, Norma P.; Gerard, Craig

    2000-01-01

    Chemokines provide signals for activation and recruitment of effector cells into sites of inflammation, acting via specific G protein–coupled receptors. However, in vitro data demonstrating the presence of multiple ligands for a given chemokine receptor, and often multiple receptors for a given chemokine, have led to concerns of biologic redundancy. Here we show that acute cardiac allograft rejection is accompanied by progressive intragraft production of the chemokines interferon (IFN)-γ–inducible protein of 10 kD (IP-10), monokine induced by IFN-γ (Mig), and IFN-inducible T cell α chemoattractant (I-TAC), and by infiltration of activated T cells bearing the corresponding chemokine receptor, CXCR3. We used three in vivo models to demonstrate a role for CXCR3 in the development of transplant rejection. First, CXCR3-deficient (CXCR3−/−) mice showed profound resistance to development of acute allograft rejection. Second, CXCR3−/− allograft recipients treated with a brief, subtherapeutic course of cyclosporin A maintained their allografts permanently and without evidence of chronic rejection. Third, CXCR+/+ mice treated with an anti-CXCR3 monoclonal antibody showed prolongation of allograft survival, even if begun after the onset of rejection. Taken in conjunction with our findings of CXCR3 expression in rejecting human cardiac allografts, we conclude that CXCR3 plays a key role in T cell activation, recruitment, and allograft destruction. PMID:11085753

  11. Solution structure of the complex between poxvirus-encoded CC chemokine inhibitor vCCI and human MIP-1β

    SciTech Connect

    Zhang, Li; DeRider, Michele; McCornack, Milissa A.; Jao, Chris; Isern, Nancy G.; Ness, Traci; Moyer, Richard; Liwang, Patricia J.

    2006-09-19

    Chemokines (chemotactic cytokines) comprise a large family of proteins that recruit and activate leukocytes, giving chemokines a major role in both the immune response and inflammation-related diseases. The poxvirus-encoded viral CC chemokine inhibitor (vCCI) binds to many CC chemokines with high affinity, acting as a potent inhibitor of chemokine action. We have used heteronuclear multidimensional NMR to determine the first structure of an orthopoxvirus vCCI in complex with a human CC chemokine MIP-1β. vCCI binds to the chemokine with 1:1 stoichiometry, using residues from its β-sheet II to interact with the a surface of MIP-1β that includes the N-terminus, the following residues in the so-called N-loop20’s region, and the 40’s loop. This structure reveals a general strategy of vCCI for selective chemokine binding, as vCCI appears to interact most stronglyinteracts most directly with residues that are conserved among a subset of CC chemokines, but are not conservednot among the other chemokine subfamilies. This structure reveals a general strategy of vCCI for selective chemokine binding. Chemokines play critical roles in the immune system, causing chemotaxis of a variety of cells to sites of infection and inflammation, as well as mediating cell homing and immune system development 1(Baggiolini 2001). To date, about 50 chemokines have been identified, and these small proteins (7-14 kDa) are believed to function by binding with endothelial or matrix glycosaminoglycans to form a concentration gradient that is then sensed by high affinity, 7-transmembrane domain G-protein coupled chemokine receptors on the surface of immune cells surface. The chemokine system is critical for host defense in healthy individuals, butand can also lead to diseases including asthma, arthritis, and atherosclerosis in the case of malfunction, often due to inappropriate inflammation and subsequent tissue damage 2(Gerard and Rollins 2001). There are four subfamilies of chemokines, CC

  12. Cysteine cathepsin activity regulation by glycosaminoglycans.

    PubMed

    Novinec, Marko; Lenarčič, Brigita; Turk, Boris

    2014-01-01

    Cysteine cathepsins are a group of enzymes normally found in the endolysosomes where they are primarily involved in intracellular protein turnover but also have a critical role in MHC II-mediated antigen processing and presentation. However, in a number of pathologies cysteine cathepsins were found to be heavily upregulated and secreted into extracellular milieu, where they were found to degrade a number of extracellular proteins. A major role in modulating cathepsin activities play glycosaminoglycans, which were found not only to facilitate their autocatalytic activation including at neutral pH, but also to critically modulate their activities such as in the case of the collagenolytic activity of cathepsin K. The interaction between cathepsins and glycosaminoglycans will be discussed in more detail.

  13. Mig and IP-10: CXC chemokines that target lymphocytes.

    PubMed

    Farber, J M

    1997-03-01

    Mig and IP-10 are related members of the CXC subfamily of the chemokine family of cytokines. The murine Mig (MuMig), human IP-10, and the mouse homologue of IP-10, Crg-2, were all identified due to the dramatic inductions of their genes in monocytic cells treated with interferon-gamma (IFN-gamma). Studies using recombinant (r) human proteins show that, unlike most other CXC chemokines, rHuMig and rIP-10 have no activity on neutrophils but appear to target lymphocytes specifically. rHuMig and rIP-10 are active as chemotactic factors for stimulated, but not for resting, T cells. Studies done in vitro and in vivo have shown that rHuMig and rIP-10 share additional activities, including inhibition of neovascularization, inhibition of hematopoietic progenitor cells, and anti-tumor effects. rHuMig and rIP-10 show reciprocal desensitization on activated T cells and have been demonstrated to share a receptor, CXCR3. The genes for both MuMig and Crg-2 are highly expressed in multiple tissues during experimental viral and protozoan infections in mice, but their patterns of expression differ. This suggests that the Migs and IP-10/Crg-2 may play roles in host defense and that, despite their similar activities assayed in vitro, Mig and IP-10/Crg-2 may serve non-redundant functions in vivo.

  14. Elevated Urinary T Helper 1 Chemokine Levels in Newly Diagnosed Hypertensive Obese Children

    PubMed Central

    Övünç Hacıhamdioğlu, Duygu; Zeybek, Cengiz; Gök, Faysal; Pekel, Aysel; Muşabak, Uğur

    2015-01-01

    Objective: Increasing evidence suggests that T helper (Th) cells play a significant role in the pathogenesis of hypertension. The aim of this study was to evaluate the effect of obesity and anti-hypertensive treatment on urinary Th1 chemokines. Methods: The study groups consisted of three types of patients: hypertensive obese, healthy, and non-hypertensive obese. Pre-treatment and post-treatment samples of the hypertensive obese group and one sample from the other two groups were evaluated for urinary chemokine: regulated on activation, normal T cell expressed and secreted (RANTES), interferon-gamma-inducible protein 10 (IP10), and monokine induced by interferon-gamma (MIG). In the hypertensive obese group, urine microalbumin: creatinine ratio was examined before and after treatment. We recommended lifestyle changes to all patients. Captopril was started in those who could not be controlled with lifestyle changes and those who had stage 2 hypertension. Results: Twenty-four hypertensive obese (mean age 13.1), 27 healthy (mean age 11.2) and 22 non-hypertensive obese (mean age 11.5) children were investigated. The pre-treatment urine albumin: creatinine ratio was positively correlated with pre-treatment MIG levels (r=0.41, p<0.05). RANTES was significantly higher in the pre-treatment hypertensive and non-hypertensive obese group than in the controls. The urinary IP10 and MIG levels were higher in the pre-treatment hypertensive obese group than in the non-hypertensive obese. Comparison of the pre- and post-treatment values indicated significant decreases in RANTES, IP10, and MIG levels in the hypertensive obese group (p<0.05). Conclusion: Th1 cells could be activated in obese hypertensive children before the onset of clinical indicators of target organ damage. Urinary RANTES seemed to be affected by both hypertension and obesity, and urinary IP10 and MIG seemed to be affected predominantly by hypertension. PMID:26831550

  15. Dual effects of noradrenaline on astroglial production of chemokines and pro-inflammatory mediators

    PubMed Central

    2013-01-01

    Background Noradrenaline (NA) is known to limit neuroinflammation. However, the previously described induction by NA of a chemokine involved in the progression of immune/inflammatory processes, such as chemokine (C-C motif) ligand 2 (CCL2)/monocyte chemotactic protein-1 (MCP-1), apparently contradicts NA anti-inflammatory actions. In the current study we analyzed NA regulation of astroglial chemokine (C-X3-C motif) ligand 1 (CX3CL1), also known as fractalkine, another chemokine to which both neuroprotective and neurodegenerative actions have been attributed. In addition, NA effects on other chemokines and pro-inflammatory mediators were also analyzed. Methods Primary astrocyte-enriched cultures were obtained from neonatal Wistar rats. These cells were incubated for different time durations with combinations of NA and lipopolysaccharide (LPS). The expression and synthesis of different proteins was measured by RT-PCR and enzyme-linked immunosorbent assay (ELISA) or enzyme immunoassays. Data were analyzed by one-way analysis of variance (ANOVA), followed by Newman-Keuls multiple comparison tests. Results The data presented here show that in control conditions, NA induces the production of CX3CL1 in rat cultured astrocytes, but in the presence of an inflammatory stimulus, such as LPS, NA has the opposite effect inhibiting CX3CL1 production. This inversion of NA effect was also observed for MCP-1. Based on the observation of this dual action, NA regulation of different chemokines and pro-inflammatory cytokines was also analyzed, observing that in most cases NA exerts an inhibitory effect in the presence of LPS. One characteristic exception was the induction of cyclooxygenase-2 (COX-2), where a summative effect was detected for both LPS and NA. Conclusion These data suggest that NA effects on astrocytes can adapt to the presence of an inflammatory agent reducing the production of certain cytokines, while in basal conditions NA may have the opposite effect and help to

  16. Overview of Complement Activation and Regulation

    PubMed Central

    Noris, Marina; Remuzzi, Giuseppe

    2013-01-01

    Summary Complement is an important component of the innate immune system that is crucial for defense from microbial infections and for clearance of immune complexes and injured cells. In normal conditions complement is tightly controlled by a number of fluid-phase and cell surface proteins to avoid injury to autologous tissues. When complement is hyperactivated, as occurs in autoimmune diseases or in subjects with dysfunctional regulatory proteins, it drives a severe inflammatory response in numerous organs. The kidney appears to be particularly vulnerable to complement-mediated inflammatory injury. Injury may derive from deposition of circulating active complement fragments in glomeruli, but complement locally produced and activated in the kidney also may have a role. Many kidney disorders have been linked to abnormal complement activation, including immune-complex–mediated glomerulonephritis and rare genetic kidney diseases, but also tubulointerstitial injury associated with progressive proteinuric diseases or ischemia-reperfusion. PMID:24161035

  17. Dietary Methanol Regulates Human Gene Activity

    PubMed Central

    Komarova, Tatiana V.; Sheshukova, Ekaterina V.; Kosorukov, Vyacheslav S.; Kiryanov, Gleb I.; Dorokhov, Yuri L.

    2014-01-01

    Methanol (MeOH) is considered to be a poison in humans because of the alcohol dehydrogenase (ADH)-mediated conversion of MeOH to formaldehyde (FA), which is toxic. Our recent genome-wide analysis of the mouse brain demonstrated that an increase in endogenous MeOH after ADH inhibition led to a significant increase in the plasma MeOH concentration and a modification of mRNA synthesis. These findings suggest endogenous MeOH involvement in homeostasis regulation by controlling mRNA levels. Here, we demonstrate directly that study volunteers displayed increasing concentrations of MeOH and FA in their blood plasma when consuming citrus pectin, ethanol and red wine. A microarray analysis of white blood cells (WBC) from volunteers after pectin intake showed various responses for 30 significantly differentially regulated mRNAs, most of which were somehow involved in the pathogenesis of Alzheimer's disease (AD). There was also a decreased synthesis of hemoglobin mRNA, HBA and HBB, the presence of which in WBC RNA was not a result of red blood cells contamination because erythrocyte-specific marker genes were not significantly expressed. A qRT-PCR analysis of volunteer WBCs after pectin and red wine intake confirmed the complicated relationship between the plasma MeOH content and the mRNA accumulation of both genes that were previously identified, namely, GAPDH and SNX27, and genes revealed in this study, including MME, SORL1, DDIT4, HBA and HBB. We hypothesized that human plasma MeOH has an impact on the WBC mRNA levels of genes involved in cell signaling. PMID:25033451

  18. Chemokines and Chemokine Receptors in Susceptibility to HIV-1 Infection and Progression to AIDS

    PubMed Central

    Chatterjee, Animesh; Rathore, Anurag; Vidyant, Sanjukta; Kakkar, Kavita; Dhole, Tapan N.

    2012-01-01

    A multitude of host genetic factors plays a crucial role in susceptibility to HIV-1 infection and progression to AIDS, which is highly variable among individuals and populations. This review focuses on the chemokine-receptor and chemokine genes, which were extensively studied because of their role as HIV co-receptor or co-receptor competitor and influences the susceptibility to HIV-1 infection and progression to AIDS in HIV-1 infected individuals. PMID:22377730

  19. Keratinocytes-associated chemokines and enzymatically quiescent heparanase induce the binding of resting CD4+ T cells.

    PubMed

    Hershkoviz, R; Marikovsky, M; Gilat, D; Lider, O

    1996-02-01

    Whether the chemokines macrophage inflammatory protein-1 beta (MIP-1 beta) and regulated on activation normal T expressed and secreted (RANTES), which interact specifically with glycosaminoglycans and thus mediate the recruitment, attachment, and migration of leukocytes to vascular endothelia and extracellular matrix, are also involved in interactions between CD4+ murine T lymphocytes and keratinocytes was examined. We have previously observed that depending on the local pH, a mammalian extracellular matrix-degrading enzyme, endo-beta-D glucuronidase (heparanase), which cleaves heparin sulfate proteoglycans, can function wither as an enzyme or as an adhesion molecule for CD4+ T lymphocytes. Herein, the involvement of heparanase in T cell-keratinocyte interactions was also probed. At 37 degree C and pH 7.2, radioactively labeled MIP-1 beta, RANTES, and heparanase bound to confluent layers of resting keratinocytes in a saturable and an heparan sulfate- or heparin-dependent manner, and thereby induced the adhesion of resting CD4+ T cells to keratinocytes. At a relatively acidic pH characteristic of inflammatory milieu, enzymatically active heparanase did not bind to the keratinocytes but, rather, inhibited the binding of MIP-1beta, RANTES, and the enzymatically quiescent heparanase to keratinocytes. These results suggest that certain chemokines and heparanase may function to restrict passing leukocytes, notable T lymphocytes, in the cutaneous micro-environment, a site which is continuously challenged with antigens. These keratinocyte-bound lymphocytes can serve as a reservoir of immediate responders to immunological stimuli. PMID:8601723

  20. Structure-function analysis of the extracellular domains of the Duffy antigen/receptor for chemokines: characterization of antibody and chemokine binding sites.

    PubMed

    Tournamille, Christophe; Filipe, Anne; Wasniowska, Kazimiera; Gane, Pierre; Lisowska, Elwira; Cartron, Jean-Pierre; Colin, Yves; Le Van Kim, Caroline

    2003-09-01

    The Duffy antigen/receptor for chemokines (DARC), a seven-transmembrane glycoprotein carrying the Duffy (Fy) blood group, acts as a widely expressed promiscuous chemokine receptor. In a structure-function study, we analysed the binding of chemokines and anti-Fy monoclonal antibodies (mAbs) to K562 cells expressing 39 mutant forms of DARC with alanine substitutions spread out on the four extracellular domains (ECDs). Using synthetic peptides, we defined previously the Fy6 epitope (22-FEDVW-26), and we characterized the Fya epitope as the linear sequence 41-YGANLE-46. In agreement with these results, mutations of F22-E23, V25 and Y41, G42, N44, L45 on ECD1 abolished the binding of anti-Fy6 and anti-Fya mAbs to K562 cells respectively, Anti-Fy3 binding was abolished by D58-D59 (ECD1), R124 (ECD2), D263 and D283 (ECD4) substitutions. Mutations of C51 (ECD1), C129 (ECD2), C195 (ECD3) and C276 (ECD4 severely reduced anti-Fy3 and CXC-chemokine ligand 8 (CXCL-8) binding. CXCL-8 binding was also abrogated by mutations of F22-E23, P50 (ECD1) and D263, R267, D283 (ECD4). These results defined the Fya epitope and suggested that (1) two disulphide bridges are involved in the creation of an active chemokine binding pocket; (2) a limited number of amino acids in ECDs 1-4 participate in CXCL-8 binding; and (3) Fy3 is a conformation-dependent epitope involving all ECDs. We also showed that N-glycosylation of DARC occurred on N16SS and did not influence antibody and chemokine binding.

  1. Emerging importance of chemokine receptor CXCR3 and its ligands in cardiovascular diseases.

    PubMed

    Altara, Raffaele; Manca, Marco; Brandão, Rita D; Zeidan, Asad; Booz, George W; Zouein, Fouad A

    2016-04-01

    The CXC chemokines, CXCL4, -9, -10, -11, CXCL4L1, and the CC chemokine CCL21, activate CXC chemokine receptor 3 (CXCR3), a cell-surface G protein-coupled receptor expressed mainly by Th1 cells, cytotoxic T (Tc) cells and NK cells that have a key role in immunity and inflammation. However, CXCR3 is also expressed by vascular smooth muscle and endothelial cells, and appears to be important in controlling physiological vascular function. In the last decade, evidence from pre-clinical and clinical studies has revealed the participation of CXCR3 and its ligands in multiple cardiovascular diseases (CVDs) of different aetiologies including atherosclerosis, hypertension, cardiac hypertrophy and heart failure, as well as in heart transplant rejection and transplant coronary artery disease (CAD). CXCR3 ligands have also proven to be valid biomarkers for the development of heart failure and left ventricular dysfunction, suggesting an underlining pathophysiological relation between levels of these chemokines and the development of adverse cardiac remodelling. The observation that several of the above-mentioned chemokines exert biological actions independent of CXCR3 provides both opportunities and challenges for developing effective drug strategies. In this review, we provide evidence to support our contention that CXCR3 and its ligands actively participate in the development and progression of CVDs, and may additionally have utility as diagnostic and prognostic biomarkers.

  2. Emerging importance of chemokine receptor CXCR3 and its ligands in cardiovascular diseases.

    PubMed

    Altara, Raffaele; Manca, Marco; Brandão, Rita D; Zeidan, Asad; Booz, George W; Zouein, Fouad A

    2016-04-01

    The CXC chemokines, CXCL4, -9, -10, -11, CXCL4L1, and the CC chemokine CCL21, activate CXC chemokine receptor 3 (CXCR3), a cell-surface G protein-coupled receptor expressed mainly by Th1 cells, cytotoxic T (Tc) cells and NK cells that have a key role in immunity and inflammation. However, CXCR3 is also expressed by vascular smooth muscle and endothelial cells, and appears to be important in controlling physiological vascular function. In the last decade, evidence from pre-clinical and clinical studies has revealed the participation of CXCR3 and its ligands in multiple cardiovascular diseases (CVDs) of different aetiologies including atherosclerosis, hypertension, cardiac hypertrophy and heart failure, as well as in heart transplant rejection and transplant coronary artery disease (CAD). CXCR3 ligands have also proven to be valid biomarkers for the development of heart failure and left ventricular dysfunction, suggesting an underlining pathophysiological relation between levels of these chemokines and the development of adverse cardiac remodelling. The observation that several of the above-mentioned chemokines exert biological actions independent of CXCR3 provides both opportunities and challenges for developing effective drug strategies. In this review, we provide evidence to support our contention that CXCR3 and its ligands actively participate in the development and progression of CVDs, and may additionally have utility as diagnostic and prognostic biomarkers. PMID:26888559

  3. 15 CFR 922.102 - Prohibited or otherwise regulated activities.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 15 Commerce and Foreign Trade 3 2012-01-01 2012-01-01 false Prohibited or otherwise regulated activities. 922.102 Section 922.102 Commerce and Foreign Trade Regulations Relating to Commerce and Foreign Trade (Continued) NATIONAL OCEANIC AND ATMOSPHERIC ADMINISTRATION, DEPARTMENT OF COMMERCE OCEAN AND COASTAL RESOURCE MANAGEMENT NATIONAL...

  4. 15 CFR 922.193 - Prohibited or otherwise regulated activities.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 15 Commerce and Foreign Trade 3 2011-01-01 2011-01-01 false Prohibited or otherwise regulated activities. 922.193 Section 922.193 Commerce and Foreign Trade Regulations Relating to Commerce and Foreign Trade (Continued) NATIONAL OCEANIC AND ATMOSPHERIC ADMINISTRATION, DEPARTMENT OF COMMERCE OCEAN AND COASTAL RESOURCE MANAGEMENT NATIONAL...

  5. Physical Activity and Self-Regulation Strategy Use in Adolescents

    ERIC Educational Resources Information Center

    Matthews, James; Moran, Aidan

    2011-01-01

    Objective: To examine the degree to which the use of selected theoretically derived self-regulation strategies (eg, goal setting) could predict adolescents' self-reported leisure-time physical activity behavior. Method: Two hundred thirty-three (M age = 15.88) high school students completed measures assessing their self-regulation strategy use and…

  6. Genetic variants in the chemokines and chemokine receptors in Chagas disease.

    PubMed

    Flórez, Oscar; Martín, Javier; González, Clara Isabel

    2012-08-01

    Clinical symptoms of Chagas' disease occur in 30% of the individuals infected with Trypanosoma cruzi and are characterised by heart inflammation and dysfunction. Chemokines and chemokine receptors control the migration of leukocytes during the inflammatory process and are involved in the modulation of Th1 or Th2 responses. To determine their influence, we investigated the possible role of CCL5/RANTES and CXCL8/IL8 chemokines, and CCR2 and CCR5 chemokines receptors cluster gene polymorphisms with the development of chagasic cardiomyopathy. Our study included 260 Chagas seropositive individuals (asymptomatic, n=130; cardiomyopathic, n=130) from an endemic area of Colombia. Genotyping was performed by polymerase chain reaction restriction fragment length polymorphism (PCR-RFLP) and TaqMan SNP genotyping assay. We found statistically significant differences in the distribution of the CCR5 human haplogroup (HH)-A (p=0.027; OR=3.78, 95% CI=1.04-13.72). Moreover, we found that the CCR5-2733 G and CCR5-2554 T alleles are associated, respectively, with a reduced risk of susceptibility and severity to develop chagasic cardiomyopathy. No other associations were found to be significant for the other polymorphisms analysed in the CCR5, CCR2, CCL5/RANTES and CXCL8/IL8 genes. Our data suggest that the analysed chemokines and chemokine receptor genetic variants have a weak but important association with the development of chagasic cardiomyopathy in the population under study.

  7. Chemokine/chemokine receptor pair CCL20/CCR6 in human colorectal malignancy: An overview

    PubMed Central

    Frick, Vilma Oliveira; Rubie, Claudia; Keilholz, Ulrich; Ghadjar, Pirus

    2016-01-01

    Chemokines belong to a superfamily of small, cytokine-like proteins, which induce multiple physiological functions, particularly cytoskeletal rearrangement and compartment-specific migration through their interaction with G-protein-coupled receptors. Chemokines and their receptors have been widely acknowledged as essential and selective mediators in leukocyte migration in inflammatory response. It is now established that the chemokine/chemokine receptor system is also used by cancer cells to direct lymphatic and haematogenous spreading and additionally has an impact on the site of metastatic growth of different tumours. In recent years an increasing number of studies have drawn attention to CC-chemokine cysteine motif chemokine ligand 20 (CCL20) and its physiological sole receptor CCR6 to play a role in the onset, development and metastatic spread of various gastrointestinal cancer entities. Among various cancer types CCR6 was also demonstrated to be significantly overexpressed in colorectal cancer (CRC) and stimulation by its physiological ligand CCL20 has been reported to promote CRC cell proliferation and migration in vitro. Further, the CCL20/CCR6 system apparently plays a role in the organ-selective liver metastasis of CRC. Here we review the literature on expression patterns of CCL20 and CCR6 and their physiological interactions as well as the currently presumed role of CCL20 and CCR6 in the formation of CRC and the development of liver metastasis, providing a potential basis for novel treatment strategies. PMID:26811629

  8. Renalase regulates peripheral and central dopaminergic activities

    PubMed Central

    Serrão, Maria Paula; Soares-Silva, Isabel; Fernandes-Cerqueira, Cátia; Simões-Silva, Liliana; Pinho, Maria João; Remião, Fernando; Sampaio-Maia, Benedita; Desir, Gary V.; Pestana, Manuel

    2014-01-01

    Renalase is a recently identified FAD/NADH-dependent amine oxidase mainly expressed in kidney that is secreted into blood and urine where it was suggested to metabolize catecholamines. The present study evaluated central and peripheral dopaminergic activities in the renalase knockout (KO) mouse model and examined the changes induced by recombinant renalase (RR) administration on plasma and urine catecholamine levels. Compared with wild-type (WT) mice, KO mice presented increased plasma levels of epinephrine (Epi), norepinephrine (NE), and dopamine (DA) that were accompanied by increases in the urinary excretion of Epi, NE, DA. In addition, the KO mice presented an increase in urinary DA-to-l-3,4-dihydroxyphenylalanine (l-DOPA) ratios without changes in renal tubular aromatic-l-amino acid decarboxylase (AADC) activity. By contrast, the in vivo administration of RR (1.5 mg/kg sc) to KO mice was accompanied by significant decreases in plasma levels of Epi, DA, and l-DOPA as well as in urinary excretion of Epi, DA, and DA-to-l-DOPA ratios notwithstanding the accompanied increase in renal AADC activity. In addition, the increase in renal DA output observed in renalase KO mice was accompanied by an increase in the expression of the L-type amino acid transporter like (LAT) 1 that is reversed by the administration of RR in these animals. These results suggest that the overexpression of LAT1 in the renal cortex of the renalase KO mice might contribute to the enhanced l-DOPA availability/uptake and consequently to the activation of the renal dopaminergic system in the presence of renalase deficiency. PMID:25411385

  9. Ragweed-allergic subjects have decreased serum levels of chemokines CCL2, CCL3, CCL4 and CCL5 out of the pollen season

    PubMed Central

    Kostova, Zhivka; Batsalova, Tsvetelina; Moten, Dzhemal; Teneva, Ivanka

    2016-01-01

    CC-chemokines are important mediators of the allergic responses and regulate the cell trafficking. The aim of this study was to examine the serum levels of CCL2/MCP-1, CCL3/MIP-1α, CCL4/MIP-1β and CCL5/RANTES, and to determine whether there are differences between ragweed-allergic subjects and healthy individuals out of the pollen season. Peripheral blood samples were collected from 24 subjects allergic to ragweed pollen and 12 healthy controls. Serum concentrations of chemokines/cytokines were measured by an enzyme-linked immunosorbent assay. We observed significantly decreased concentrations of CCL2/MCP-1, CCL3/MIP-1α, CCL4/MIP-1β and CCL5/RANTES in the sera of ragweed-allergic patients compared to the healthy individuals (32.2 vs. 106.4 pg/ml, 89.5 vs. 135.7 pg/ml, 63.4 vs. 119.2 pg/ml and 11.2 vs. 18.1 ng/ml, respectively, p < 0.01). In contrast to the CC-chemokines, the serum levels of IL-8/CXCL8 showed a significant increase (p < 0.05) in the allergic group compared to the non-allergic subjects. Interleukin 4 levels were similar in both groups. In the sera of allergic patients, we have also detected significantly elevated levels of ragweed-specific IgE and IgG. However, decreased serum concentrations of the four CC-chemokines and elevated levels of IL-8/CXCL8 can be used as biomarkers for more accurate evaluation of the allergic status of patients with pollen allergy out of the season, to study the mechanisms for activation/inhibition of the subclinical allergic responses and for development of therapeutic strategies. PMID:26862308

  10. p21-activated kinase 2 regulates HSPC cytoskeleton, migration, and homing via CDC42 activation and interaction with β-Pix.

    PubMed

    Reddy, Pavankumar N G; Radu, Maria; Xu, Ke; Wood, Jenna; Harris, Chad E; Chernoff, Jonathan; Williams, David A

    2016-04-21

    Cytoskeletal remodeling of hematopoietic stem and progenitor cells (HSPCs) is essential for homing to the bone marrow (BM). The Ras-related C3 botulinum toxin substrate (Rac)/cell division control protein 42 homolog (CDC42) effector p21-activated kinase (Pak2) has been implicated in HSPC homing and engraftment. However, the molecular pathways mediating Pak2 functions in HSPCs are unknown. Here, we demonstrate that both Pak2 kinase activity and its interaction with the PAK-interacting exchange factor-β (β-Pix) are required to reconstitute defective ITALIC! Pak2 (ITALIC! Δ/Δ)HSPC homing to the BM. Pak2 serine/threonine kinase activity is required for stromal-derived factor-1 (SDF1α) chemokine-induced HSPC directional migration, whereas Pak2 interaction with β-Pix is required to regulate the velocity of HSPC migration and precise F-actin assembly. Lack of SDF1α-induced filopodia and associated abnormal cell protrusions seen in ITALIC! Pak2 (ITALIC! Δ/Δ)HSPCs were rescued by wild-type (WT) Pak2 but not by a Pak2-kinase dead mutant (KD). Expression of a β-Pix interaction-defective mutant of Pak2 rescued filopodia formation but led to abnormal F-actin bundles. Although CDC42 has previously been considered an upstream regulator of Pak2, we found a paradoxical decrease in baseline activation of CDC42 in ITALIC! Pak2 (ITALIC! Δ/Δ)HSPCs, which was rescued by expression of Pak2-WT but not by Pak2-KD; defective homing of ITALIC! Pak2-deleted HSPCs was rescued by constitutive active CDC42. These data demonstrate that both Pak2 kinase activity and its interaction with β-Pix are essential for HSPC filopodia formation, cytoskeletal integrity, and homing via activation of CDC42. Taken together, we provide mechanistic insights into the role of Pak2 in HSPC migration and homing.

  11. Temperature Regulator for Actively Cooled Structures

    NASA Technical Reports Server (NTRS)

    Blosser, Max (Inventor); Kelly, H. Neale (Inventor)

    1995-01-01

    In active cooling of a structure it is beneficial to use a plurality of passages for conducting coolant to various portions of the structure. Since most structures do not undergo isotropic thermal loads it is desirable to allow for variation in coolant flow to each area of the structure. The present invention allows for variable flow by a variation of the area of a portion of each of the coolant passages. Shape memory alloys and bi-material springs are used to produce passages that change flow area as a function of temperature.

  12. Transferring the C-terminus of the chemokine CCL21 to CCL19 confers enhanced heparin binding.

    PubMed

    Barmore, Austin J; Castex, Sally M; Gouletas, Brittany A; Griffith, Alex J; Metz, Slater W; Muelder, Nicolas G; Populin, Michael J; Sackett, David M; Schuster, Abigail M; Veldkamp, Christopher T

    2016-09-01

    Chemokines direct the migration of cells during various immune processes and are involved in many disease states. For example, CCL19 and CCL21, through activation of the CCR7 receptor, recruit dendritic cells and naïve T-cells to the secondary lymphoid organs aiding in balancing immune response and tolerance. However, CCL19 and CCL21 can also direct the metastasis of CCR7 expressing cancers. Chemokine binding to glycosaminoglycans, such as heparin, is as important to chemokine function as receptor activation. CCL21 is unique in that it contains an extended C-terminus not found in other chemokines like CCL19. Deletion of this extended C-terminus reduces CCL21's affinity for heparin and transferring the CCL21 C-terminus to CCL19 enhances heparin binding mainly through non-specific, electrostatic interactions. PMID:27338641

  13. Kinase active Misshapen regulates Notch signaling in Drosophila melanogaster.

    PubMed

    Mishra, Abhinava K; Sachan, Nalani; Mutsuddi, Mousumi; Mukherjee, Ashim

    2015-11-15

    Notch signaling pathway represents a principal cellular communication system that plays a pivotal role during development of metazoans. Drosophila misshapen (msn) encodes a protein kinase, which is related to the budding yeast Ste20p (sterile 20 protein) kinase. In a genetic screen, using candidate gene approach to identify novel kinases involved in Notch signaling, we identified msn as a novel regulator of Notch signaling. Data presented here suggest that overexpression of kinase active form of Msn exhibits phenotypes similar to Notch loss-of-function condition and msn genetically interacts with components of Notch signaling pathway. Kinase active form of Msn associates with Notch receptor and regulate its signaling activity. We further show that kinase active Misshapen leads to accumulation of membrane-tethered form of Notch. Moreover, activated Msn also depletes Armadillo and DE-Cadherin from adherens junctions. Thus, this study provides a yet unknown mode of regulation of Notch signaling by Misshapen. PMID:26431585

  14. Suppression of silent information regulator 1 activity in noncancerous tissues of hepatocellular carcinoma: Possible association with non-B non-C hepatitis pathogenesis

    PubMed Central

    Konishi, Hideyuki; Shirabe, Ken; Nakagawara, Hidekazu; Harimoto, Norifumi; Yamashita, Yo-Ichi; Ikegami, Toru; Yoshizumi, Tomoharu; Soejima, Yuji; Oda, Yoshinao; Maehara, Yoshihiko

    2015-01-01

    Silent information regulator 1 (SIRT1) is a nicotinamide adenine dinucleotide (NAD+)-dependent protein deacetylase. In mice, mSirt1 deficiency causes the onset of fatty liver via regulation of the hepatic nutrient metabolism pathway. In this study, we demonstrate SIRT1 expression, activity and NAD+ regulation using noncancerous liver tissue specimens from hepatocellular carcinoma patients with non-B non-C (NBNC) hepatitis. SIRT1 expression levels were higher in NBNC patients than in healthy donors, while SIRT1 histone H3K9 deacetylation activity was suppressed in NBNC patients. In the liver of hepatitis patients, decreased NAD+ amounts and its regulatory enzyme nicotinamide phosphoribosyltransferase expression levels were observed, and this led to inhibition of SIRT1 activity. SIRT1 expression was associated with HIF1 protein accumulation in both the NBNC liver and liver cancer cell lines. These results may indicate that the NBNC hepatitis liver is exposed to hypoxic conditions. In HepG2 cells, hypoxia induced inflammatory chemokines, such as CXCL10 and MCP-1. These inductions were suppressed in rich NAD+ condition, and by SIRT1 activator treatment. In conclusion, hepatic SIRT1 activity was repressed in NBNC patients, and normalization of NAD+ amounts and activation of SIRT1 could improve the inflammatory condition in the liver of NBNC hepatitis patients. PMID:25736100

  15. Upregulation of expression of the chemokine receptor CCR5 by hydrogen peroxide in human monocytes.

    PubMed

    Lehoux, Geneviève; Le Gouill, Christian; Stankova, Jana; Rola-Pleszczynski, Marek

    2003-02-01

    The objective of this study was to test the hypothesis that an oxidative stress can serve as a signal to regulate the expression of CCR5. When human monocytes were exposed to graded concentration of hydrogen peroxide (H(2)O(2)), CCR5 mRNA levels increased maximally at 4 h of exposure to 200 microM of H(2)O(2) and decreased by 24 h of treatment. Pretreatment of monocytes with the NF-kappaB inhibitor BAY 11-8072 blocked the H(2)O(2)-induced augmentation of CCR5 mRNA expression, suggesting a role for this transcription factor in the regulation of CCR5 expression. CCR5 protein expression on the plasma membrane was also increased by treatment with H(2)O(2,) as assessed by flow cytometry. This was accompanied by enhanced responsiveness of H(2)O(2)-pretreated monocytes to the CCR5 ligand MIP-1beta in terms of chemotaxis and c-fos gene activation. Our results suggest that oxidative stress may indeed modulate the expression of chemokine receptors and thus contribute to regulation of the inflammatory process.

  16. Upregulation of expression of the chemokine receptor CCR5 by hydrogen peroxide in human monocytes.

    PubMed Central

    Lehoux, Geneviève; Le Gouill, Christian; Stankova, Jana; Rola-Pleszczynski, Marek

    2003-01-01

    The objective of this study was to test the hypothesis that an oxidative stress can serve as a signal to regulate the expression of CCR5. When human monocytes were exposed to graded concentration of hydrogen peroxide (H(2)O(2)), CCR5 mRNA levels increased maximally at 4 h of exposure to 200 microM of H(2)O(2) and decreased by 24 h of treatment. Pretreatment of monocytes with the NF-kappaB inhibitor BAY 11-8072 blocked the H(2)O(2)-induced augmentation of CCR5 mRNA expression, suggesting a role for this transcription factor in the regulation of CCR5 expression. CCR5 protein expression on the plasma membrane was also increased by treatment with H(2)O(2,) as assessed by flow cytometry. This was accompanied by enhanced responsiveness of H(2)O(2)-pretreated monocytes to the CCR5 ligand MIP-1beta in terms of chemotaxis and c-fos gene activation. Our results suggest that oxidative stress may indeed modulate the expression of chemokine receptors and thus contribute to regulation of the inflammatory process. PMID:12745546

  17. Cytokine and Chemokine Profile in Amicrobial Pustulosis of the Folds: Evidence for Autoinflammation.

    PubMed

    Marzano, Angelo V; Tavecchio, Simona; Berti, Emilio; Gelmetti, Carlo; Cugno, Massimo

    2015-12-01

    Autoinflammation has recently been suggested in the pathogenesis of neutrophilic dermatoses but systematic studies on their cytokine profile are lacking. Notably, amicrobial pustulosis of the folds (APF), classified among neutrophilic dermatoses, has been studied only in small case series. In our University Hospital, we conducted an observational study on 15 APF patients, analyzing their clinical and laboratory features with a follow-up of 9 months to 20 years. Skin cytokine pattern of 9 of them was compared to that of 6 normal controls. In all patients, primary lesions were pustules symmetrically involving the skin folds and anogenital region with a chronic-relapsing course and responding to corticosteroids. Dapsone, cyclosporine, and tumor necrosis factor blockers were effective in refractory cases. In skin samples, the expressions of interleukin (IL)-1β, pivotal cytokine in autoinflammation, and its receptors I and II were significantly higher in APF (P = 0.005, 0.018, and 0.034, respectively) than in controls. Chemokines responsible for neutrophil recruitment such as IL-8 (P = 0.003), CXCL 1/2/3 (C-X-C motif ligand 1/2/3) (P = 0.010), CXCL 16 (P = 0.045), and RANTES (regulated on activation, normal T cell expressed and secreted) (P = 0.034) were overexpressed. Molecules involved in tissue damage like matrix metalloproteinase-2 (MMP-2) (P = 0.010) and MMP-9 (P = 0.003) were increased. APF is a pustular neutrophilic dermatosis with a typical distribution in all patients. The disorder may coexist with an underlying autoimmune/dysimmune disease but is often associated only with a few autoantibodies without a clear autoimmunity. The overexpression of cytokines/chemokines and molecules amplifying the inflammatory network supports the view that APF has an important autoinflammatory component. PMID:26683967

  18. Inflammatory microenvironment and expression of chemokines in hepatocellular carcinoma

    PubMed Central

    Han, Ke-Qi; He, Xue-Qun; Ma, Meng-Yu; Guo, Xiao-Dong; Zhang, Xue-Min; Chen, Jie; Han, Hui; Zhang, Wei-Wei; Zhu, Quan-Gang; Nian, Hua; Ma, Li-Jun

    2015-01-01

    AIM: To study the inflammatory microenvironment and expression of chemokines in hepatocellular carcinoma (HCC) in nude mice. METHODS: CBRH-7919 HCC cells were injected into the subcutaneous region of nude mice. Beginning two weeks after the challenge, tumor growth was measured every week for six weeks. The stromal microenvironment and inflammatory cell infiltration was assessed by immunohistochemistry in paired tumor and adjacent peritumoral samples, and macrophage phenotype was assessed using double-stain immunohistochemistry incorporating expression of an intracellular enzyme. A chemokine PCR array, comprised of 98 genes, was used to screen differential gene expressions, which were validated by Western blotting. Additionally, expression of identified chemokines was knocked-down by RNA interference, and the effect on tumor growth was assessed. RESULTS: Inflammatory cell infiltrates are a key feature of adjacent peritumoral tissues with increased macrophage, neutrophil, and T cell (specifically helper and activated subsets) infiltration. Macrophages within adjacent peritumoral tissues express inducible nitric oxide synthase, suggestive of a proinflammatory phenotype. Fifty-one genes were identified in tumor tissues during the progression period, including 50 that were overexpressed (including CXCL1, CXCL2 and CXCL3) and three that were underexpressed (CXCR1, Ifg and Actb). RNA interference of CXCL1 in the CBRH-7919 cells decreased the growth of tumors in nude mice and inhibited expression of CXCL2, CXCL3 and interleukin-1β protein. CONCLUSION: These findings suggest that CXCL1 plays a critical role in tumor growth and may serve as a potential molecular target for use in HCC therapy. PMID:25944999

  19. Negative regulation of mTOR activation by diacylglycerol kinases

    PubMed Central

    Gorentla, Balachandra K.; Wan, Chi-Keung

    2011-01-01

    The engagement of TCR induces T-cell activation, which initiates multiple characteristic changes such as increase in cell size, cell division, and the production of cytokines and other effector molecules. The mammalian target of rapamycin (mTOR) regulates protein synthesis, transcription, cell survival, and autophagy. Critical roles of mTOR in T-cell activation and effector/memory differentiation have been revealed using chemical inhibitors or by genetic ablation of mTOR in T cells. However, the connection between mTOR signaling and other signaling cascades downstream of TCR is unclear. We demonstrate that diacylglycerol (DAG) and TCR engagement activate signaling in both mTOR complexes 1 and 2 through the activation of the Ras–mitogen-activated protein kinase/extracellular signal–regulated kinase 1/2 (Mek1/2)–extracellular signal–regulated kinase 1/2 (Erk1/2)–activator protein 1 (AP-1), known collectively as the Ras-Mek1/2-Erk1/2-AP-1 pathway. Deficiency of RasGRP1 or inhibition of Mek1/2 activity drastically decreases TCR-induced mTOR activation, whereas constitutively active Ras or Mek1 promotes mTOR activation. Although constitutively active Akt promotes TCR-induced mTOR activation, such activation is attenuated by Mek1/2 inhibition. We demonstrated further that DAG kinases (DGKs) α and ζ, which terminate DAG-mediated signaling, synergistically inhibit TCR-induced mTOR activation by inhibiting the Ras-Mek1/2-Erk/12 pathway. These observations provide novel insights into the regulation of mTOR activation. PMID:21310925

  20. Interferon-Inducible CXC Chemokines Directly Contribute to Host Defense against Inhalational Anthrax in a Murine Model of Infection

    PubMed Central

    Crawford, Matthew A.; Burdick, Marie D.; Glomski, Ian J.; Boyer, Anne E.; Barr, John R.; Mehrad, Borna; Strieter, Robert M.; Hughes, Molly A.

    2010-01-01

    Chemokines have been found to exert direct, defensin-like antimicrobial activity in vitro, suggesting that, in addition to orchestrating cellular accumulation and activation, chemokines may contribute directly to the innate host response against infection. No observations have been made, however, demonstrating direct chemokine-mediated promotion of host defense in vivo. Here, we show that the murine interferon-inducible CXC chemokines CXCL9, CXCL10, and CXCL11 each exert direct antimicrobial effects in vitro against Bacillus anthracis Sterne strain spores and bacilli including disruptions in spore germination and marked reductions in spore and bacilli viability as assessed using CFU determination and a fluorometric assay of metabolic activity. Similar chemokine-mediated antimicrobial activity was also observed against fully virulent Ames strain spores and encapsulated bacilli. Moreover, antibody-mediated neutralization of these CXC chemokines in vivo was found to significantly increase host susceptibility to pulmonary B. anthracis infection in a murine model of inhalational anthrax with disease progression characterized by systemic bacterial dissemination, toxemia, and host death. Neutralization of the shared chemokine receptor CXCR3, responsible for mediating cellular recruitment in response to CXCL9, CXCL10, and CXCL11, was not found to increase host susceptibility to inhalational anthrax. Taken together, our data demonstrate a novel, receptor-independent antimicrobial role for the interferon-inducible CXC chemokines in pulmonary innate immunity in vivo. These data also support an immunomodulatory approach for effectively treating and/or preventing pulmonary B. anthracis infection, as well as infections caused by pathogenic and potentially, multi-drug resistant bacteria including other spore-forming organisms. PMID:21124994

  1. Effect of a topical steroid on gene expressions for chemokines in mice with contact hypersensitivity.

    PubMed

    Mitsui, Gaku; Hirano, Takeo; Niwano, Yoshimi; Mitsui, Kazutaka; Ohara, Osamu; Yanagihara, Satoshi; Kato, Masatoshi

    2004-01-01

    Effects of a topical corticosteroid drug, diflucortolone valerate, on the mRNA expressions for four CC- and four CXC-chemokines, which have been reported to be associated with recruitment of different kinds of proinflammatory and inflammatory cells, were investigated by RT-PCR in mice with 2,4,6-trinitrochlorobenzene (TNCB)-induced contact hypersensitivity (CHS) response. All of the eight gene expressions were clearly up-regulated in the lesion site of the CHS response up to 24 h post-challenge of TNCB at which ear swelling response reached a peak, so that heavy infiltration of inflammatory cells consisting mainly of mononuclear cells and neutrophils was likely induced by these chemokines. Topical treatment with diflucortolone valerate suppressed completely the infiltrates as well as the ear swelling response. In addition, the up-regulation of gene expressions for these eight chemokines were suppressed by the treatment, indicating that the corticosteroid drug attenuates the expression of chemokine genes essential for orientating nonspecific skin response to hapten-specific CHS response through the recruitment of inflammatory cells from the circulation into the tissue site. PMID:14975360

  2. Identification of a cobia (Rachycentron canadum) CC chemokine gene and its involvement in the inflammatory response.

    PubMed

    Su, Youlu; Guo, Zhixun; Xu, Liwen; Jiang, Jingzhe; Wang, Jiangyong; Feng, Juan

    2012-01-01

    The chemokines regulate immune cell migration under inflammatory and physiological conditions. We investigated a CC chemokine gene (RcCC1) from cobia (Rachycentron canadum). The full-length RcCC1 cDNA is comprised 673 nucleotides and encodes a four-cysteine arrangement 99-amino-acid protein typical of known CC chemokines. The genomic DNA of RcCC1 consists of three exons and two introns. Phylogenetic analysis showed that RcCC1 was closest to the MIP group of CC chemokines. Quantitative real-time RT-PCR (qRT-PCR) analysis revealed RcCC1 was constitutively expressed in all tissues examined, with relative strong expression in gill, blood, kidney, spleen, and head kidney. The RcCC1 transcripts in the head kidney, spleen, and liver were quickly up-regulated after stimulation with formalin-inactivated Vibrio carchariae (bacterial vaccine) or polyriboinosinic polyribocytidylic acid (poly I:C). These results indicate RcCC1 not only plays a role in homeostasis, but also may be involved in inflammatory responses to bacterial and viral infection.

  3. Analysis of Chemokine Receptor Trafficking by Site-Specific Biotinylation.

    PubMed

    Liebick, Marcel; Schläger, Christian; Oppermann, Martin

    2016-01-01

    Chemokine receptors undergo internalization and desensitization in response to ligand activation. Internalized receptors are either preferentially directed towards recycling pathways (e.g. CCR5) or sorted for proteasomal degradation (e.g. CXCR4). Here we describe a method for the analysis of receptor internalization and recycling based on specific Bir A-mediated biotinylation of an acceptor peptide coupled to the receptor, which allows a more detailed analysis of receptor trafficking compared to classical antibody-based detection methods. Studies on constitutive internalization of the chemokine receptors CXCR4 (12.1% ± 0.99% receptor internalization/h) and CCR5 (13.7% ± 0.68%/h) reveals modulation of these processes by inverse (TAK779; 10.9% ± 0.95%/h) or partial agonists (Met-CCL5; 15.6% ± 0.5%/h). These results suggest an actively driven internalization process. We also demonstrate the advantages of specific biotinylation compared to classical antibody detection during agonist-induced receptor internalization, which may be used for immunofluorescence analysis as well. Site-specific biotinylation may be applicable to studies on trafficking of transmembrane proteins, in general.

  4. Analysis of Chemokine Receptor Trafficking by Site-Specific Biotinylation

    PubMed Central

    Liebick, Marcel; Schläger, Christian; Oppermann, Martin

    2016-01-01

    Chemokine receptors undergo internalization and desensitization in response to ligand activation. Internalized receptors are either preferentially directed towards recycling pathways (e.g. CCR5) or sorted for proteasomal degradation (e.g. CXCR4). Here we describe a method for the analysis of receptor internalization and recycling based on specific Bir A-mediated biotinylation of an acceptor peptide coupled to the receptor, which allows a more detailed analysis of receptor trafficking compared to classical antibody-based detection methods. Studies on constitutive internalization of the chemokine receptors CXCR4 (12.1% ± 0.99% receptor internalization/h) and CCR5 (13.7% ± 0.68%/h) reveals modulation of these processes by inverse (TAK779; 10.9% ± 0.95%/h) or partial agonists (Met-CCL5; 15.6% ± 0.5%/h). These results suggest an actively driven internalization process. We also demonstrate the advantages of specific biotinylation compared to classical antibody detection during agonist-induced receptor internalization, which may be used for immunofluorescence analysis as well. Site-specific biotinylation may be applicable to studies on trafficking of transmembrane proteins, in general. PMID:27310579

  5. Heparanase augments inflammatory chemokine production from colorectal carcinoma cell lines.

    PubMed

    Tsunekawa, Naoki; Higashi, Nobuaki; Kogane, Yusuke; Waki, Michihiko; Shida, Hiroaki; Nishimura, Yoshio; Adachi, Hayamitsu; Nakajima, Motowo; Irimura, Tatsuro

    2016-01-22

    To explore possible roles of heparanase in cancer-host crosstalk, we examined whether heparanase influences expression of inflammatory chemokines in colorectal cancer cells. Murine colorectal carcinoma cells incubated with heparanase upregulated MCP-1, KC, and RANTES genes and released MCP-1 and KC proteins. Heparanase-dependent production of IL-8 was detected in two human colorectal carcinoma cell lines. Addition of a heparanase inhibitor Heparastatin (SF4) did not influence MCP-1 production, while both latent and mature forms of heparanase augmented MCP-1 release, suggesting that heparanase catalytic activity was dispensable for MCP-1 production. In contrast, addition of heparin to the medium suppressed MCP-1 release in a dose-dependent manner. Similarly, targeted suppression of Ext1 by RNAi significantly suppressed cell surface expression of heparan sulfate and MCP-1 production in colon 26 cells. Taken together, it is concluded that colon 26 cells transduce the heparanase-mediated signal through heparan sulfate binding. We propose a novel function for heparanase independent of its endoglycosidase activity, namely as a stimulant for chemokine production. PMID:26713365

  6. Regulation of Activation Induced Deaminase (AID) by Estrogen.

    PubMed

    Pauklin, Siim

    2016-01-01

    Regulation of Activation Induced Deaminase (AID) by the hormone estrogen has important implications for understanding adaptive immune responses as well as the involvement of AID in autoimmune diseases and tumorigenesis. This chapter describes the general laboratory techniques for analyzing AID expression and activity induced by estrogen, focusing on the isolation and preparation of cells for hormone treatment and the subsequent analysis of AID responsiveness to estrogen at the RNA level and for determining the regulation of AID activity via estrogen by analyzing Ig switch circle transcripts and mutations in switch region loci.

  7. Absence of canonical active chromatin marks in developmentally regulated genes

    PubMed Central

    Ruiz-Romero, Marina; Corominas, Montserrat; Guigó, Roderic

    2015-01-01

    The interplay of active and repressive histone modifications is assumed to play a key role in the regulation of gene expression. In contrast to this generally accepted view, we show that transcription of genes temporally regulated during fly and worm development occurs in the absence of canonically active histone modifications. Conversely, strong chromatin marking is related to transcriptional and post-transcriptional stability, an association that we also observe in mammals. Our results support a model in which chromatin marking is associated to stable production of RNA, while unmarked chromatin would permit rapid gene activation and de-activation during development. In this case, regulation by transcription factors would play a comparatively more important regulatory role. PMID:26280901

  8. Molecular cloning, characterization and expression analysis of a CC chemokine gene from miiuy croaker (Miichthys miiuy).

    PubMed

    Cheng, Yuanzhi; Sun, Yuena; Shi, Ge; Wang, Rixin; Xu, Tianjun

    2012-12-01

    Chemokines are a family of structurally related chemotactic cytokines that regulate the migration of leukocytes, under both physiological and inflammatory conditions. A partial cDNA of CC chemokine gene designed as Mimi-CC3 was isolated from miiuy croaker (Miichthys miiuy) spleen cDNA library. Unknown 3' part of the cDNA was amplified by 3'-RACE. The complete cDNA of Mimi-CC3 contains an 89-nt 5'-UTR, a 303-nt open reading frame and a 441-nt 3'-UTR. Three exons and two introns were identified in Mimi-CC3. The deduced Mimi-CC3 protein sequences contain a 22 amino acids signal peptide and a 78 amino acids mature polypeptide, which possesses the typical arrangement of four cysteines as found in other known CC chemokines. It shares low amino acid sequence identities with most other fish and mammalian CC chemokines (less than 54.1 %), but shares very high identities with large yellow croaker CC chemokine (94.6 %). Phylogenetic analysis showed that Mimi-CC3 gene may have an orthologous relationship with mammalian/amphibian CCL25 gene. Tissue expression distributed analysis showed that Mimi-CC3 gene was constitutively expressed in all nine tissues examined, although at different levels. Upon stimulated with Vibrio anguillarum, the time-course analysis using a real-time PCR showed that Mimi-CC3 transcript in kidney and liver was obviously up-regulated and reached the peak levels, followed by a recovery. Mimi-CC3 expression in kidney was more strongly increased than in liver. However, down-regulation was observed in spleen. These results indicated that Mimi-CC3 plays important roles in miiuy croaker immune response as well as in homeostatic mechanisms.

  9. Haplotype structure and linkage disequilibrium in chemokine and chemokine receptor genes

    PubMed Central

    2004-01-01

    To dissect the haplotype structure of candidate genes for disease association studies, it is important to understand the nature of genetic variation at these loci in different populations. We present a survey of haplotype structure and linkage disequilibrium of chemokine and chemokine receptor genes in 11 geographically-distinct population samples (n = 728). Chemokine proteins are involved in intercellular signalling and the immune response. These molecules are important modulators of human immunodeficiency virus (HIV)-1 infection and the progression of the acquired immune deficiency syndrome, tumour development and the metastatic process of cancer. To study the extent of genetic variation in this gene family, single nucleotide polymorphisms (SNPs) from 13 chemokine and chemokine receptor genes were genotyped using the 5' nuclease assay (TaqMan). SNP haplotypes, estimated from unphased genotypes using the Expectation-Maximization-algorithm, are described in a cluster of four CC-chemokine receptor genes (CCR3, CCR2, CCR5 and CCRL2) on chromosome 3p21, and a cluster of three CC-chemokine genes [MPIF-1 (CCL23) PARC (CCL18) and MIP- 1α (CCL3)] on chromosome 17q11-12. The 32 base pair (bp) deletion in exon 4 of CCR5 was also included in the haplotype analysis of 3p21. A total of 87.5 per cent of the variation of 14 biallelic loci scattered over 150 kilobases of 3p21 is explained by 11 haplotypes which have a frequency of at least 1 per cent in the total sample. An analysis of haplotype blocks in this region indicates recombination between CCR2 and CCR5, although long-range pairwise linkage disequilibrium across the region appears to remain intact on two common haplotypes. A reduced-median network demonstrates a clear relationship between 3p21 haplotypes, rooted by the putative ancestral haplotype determined by direct sequencing of four primate species. Analysis of six SNPs on 17q11-12 indicates that 97.5 per cent of the variation is explained by 15 haplotypes

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

    PubMed Central

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

    2015-01-01

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

  11. Chromatin Remodeling Inactivates Activity Genes and Regulates Neural Coding

    PubMed Central

    Hill, Kelly K.; Hemberg, Martin; Reddy, Naveen C.; Cho, Ha Y.; Guthrie, Arden N.; Oldenborg, Anna; Heiney, Shane A.; Ohmae, Shogo; Medina, Javier F.; Holy, Timothy E.; Bonni, Azad

    2016-01-01

    Activity-dependent transcription influences neuronal connectivity, but the roles and mechanisms of inactivation of activity-dependent genes have remained poorly understood. Genome-wide analyses in the mouse cerebellum revealed that the nucleosome remodeling and deacetylase (NuRD) complex deposits the histone variant H2A.z at promoters of activity-dependent genes, thereby triggering their inactivation. Purification of translating mRNAs from synchronously developing granule neurons (Sync-TRAP) showed that conditional knockout of the core NuRD subunit Chd4 impairs inactivation of activity-dependent genes when neurons undergo dendrite pruning. Chd4 knockout or expression of NuRD-regulated activity genes impairs dendrite pruning. Imaging of behaving mice revealed hyperresponsivity of granule neurons to sensorimotor stimuli upon Chd4 knockout. Our findings define an epigenetic mechanism that inactivates activity-dependent transcription and regulates dendrite patterning and sensorimotor encoding in the brain. PMID:27418512

  12. Developmental regulation of aromatase activity in the rat hypothalamus

    SciTech Connect

    Lephart, E.D.

    1989-01-01

    The brain of all mammalian species studied thus far contain an enzymatic activity (aromatase) that catalyzes the conversion of androgens to estrogens. The activity is highest during prenatal development and contributes to the establishment of sex differences which determine adult gonadotropin secretion patterns and reproductive behavior. The studies presented in this dissertation represent a systematic effort to elucidate the mechanism(s) that control the initiation of and contribute to maintaining rat hypothalamic aromatase activity during pre- and postnatal development. Aromatase enzyme activity was measured by the {sup 3}H{sub 2}O release assay or by traditional estrogen product isolation. Brain aromatase mRNA was detected by hybridization to a cDNA encoding rat aromatase cytochrome P-450. In both males and females the time of puberty was associated with a decline in hypothalamic aromatase activity. This decline may represent a factor underlying the peri-pubertal decrease in the sensitivity to gonadal steroid feedback that accompanies completion of puberty. The results also indicate that androgens regulate brain aromatase levels during both the prepubertal and peri-pubertal stages of sexual development and that this regulation is transiently lost in young adults. Utilizing a hypothalamic organotypic culture system, aromatase activity in vitro was maintained for as long as two days. The results of studies of a variety of hormonal and metabolic regulators suggest that prenatal aromatase activity is regulated by factor(s) that function independently from the classical cyclic AMP and protein kinase C trans-membrane signaling pathways.

  13. Adoption activities on the Internet: a call for regulation.

    PubMed

    Roby, Jini L; White, Holly

    2010-07-01

    There is a growing practice of adoption services on the Internet with varying degrees of regulation, depending on whether it is domestic infant adoption, public foster care adoption, or international adoption. Regulation is particularly lacking in domestic infant adoptions, with Web sites connecting prospective birth and adoptive parents, sometimes through an adoption brokerage service. International adoptions can also be plagued by unethical practices as the Internet has become available in both developed and developing countries. These activities, although offering the benefits of privacy and convenience, also pose serious problems of potential fraud, exploitation, and, most important, lack of professional consideration of the child's best interest. In this article, the authors review the landscape of current Internet-based adoption activities, examine the benefits and risks of Internet-based adoption activities, and call for social work self-regulation and leadership. PMID:20632655

  14. Adoption activities on the Internet: a call for regulation.

    PubMed

    Roby, Jini L; White, Holly

    2010-07-01

    There is a growing practice of adoption services on the Internet with varying degrees of regulation, depending on whether it is domestic infant adoption, public foster care adoption, or international adoption. Regulation is particularly lacking in domestic infant adoptions, with Web sites connecting prospective birth and adoptive parents, sometimes through an adoption brokerage service. International adoptions can also be plagued by unethical practices as the Internet has become available in both developed and developing countries. These activities, although offering the benefits of privacy and convenience, also pose serious problems of potential fraud, exploitation, and, most important, lack of professional consideration of the child's best interest. In this article, the authors review the landscape of current Internet-based adoption activities, examine the benefits and risks of Internet-based adoption activities, and call for social work self-regulation and leadership.

  15. The chemokine CXCL16 modulates neurotransmitter release in hippocampal CA1 area

    PubMed Central

    Di Castro, Maria Amalia; Trettel, Flavia; Milior, Giampaolo; Maggi, Laura; Ragozzino, Davide; Limatola, Cristina

    2016-01-01

    Chemokines have several physio-pathological roles in the brain. Among them, the modulation of synaptic contacts and neurotransmission recently emerged as crucial activities during brain development, in adulthood, upon neuroinflammation and neurodegenerative diseases. CXCL16 is a chemokine normally expressed in the brain, where it exerts neuroprotective activity against glutamate-induced damages through cross communication with astrocytes and the involvement of the adenosine receptor type 3 (A3R) and the chemokine CCL2. Here we demonstrated for the first time that CXCL16 exerts a modulatory activity on inhibitory and excitatory synaptic transmission in CA1 area. We found that CXCL16 increases the frequency of the miniature inhibitory synaptic currents (mIPSCs) and the paired-pulse ratio (PPR) of evoked IPSCs (eIPSCs), suggesting a presynaptic modulation of the probability of GABA release. In addition, CXCL16 increases the frequency of the miniature excitatory synaptic currents (mEPSCs) and reduces the PPR of evoked excitatory transmission, indicating that the chemokine also modulates and enhances the release of glutamate. These effects were not present in the A3RKO mice and in WT slices treated with minocycline, confirming the involvement of A3 receptors and introducing microglial cells as key mediators of the modulatory activity of CXCL16 on neurons. PMID:27721466

  16. Down-regulated peroxisome proliferator-activated receptor γ (PPARγ) in lung epithelial cells promotes a PPARγ agonist-reversible proinflammatory phenotype in chronic obstructive pulmonary disease (COPD).

    PubMed

    Lakshmi, Sowmya P; Reddy, Aravind T; Zhang, Yingze; Sciurba, Frank C; Mallampalli, Rama K; Duncan, Steven R; Reddy, Raju C

    2014-03-01

    Chronic obstructive pulmonary disease (COPD) is a progressive inflammatory condition and a leading cause of death, with no available cure. We assessed the actions in pulmonary epithelial cells of peroxisome proliferator-activated receptor γ (PPARγ), a nuclear hormone receptor with anti-inflammatory effects, whose role in COPD is largely unknown. We found that PPARγ was down-regulated in lung tissue and epithelial cells of COPD patients, via both reduced expression and phosphorylation-mediated inhibition, whereas pro-inflammatory nuclear factor-κB (NF-κB) activity was increased. Cigarette smoking is the main risk factor for COPD, and exposing airway epithelial cells to cigarette smoke extract (CSE) likewise down-regulated PPARγ and activated NF-κB. CSE also down-regulated and post-translationally inhibited the glucocorticoid receptor (GR-α) and histone deacetylase 2 (HDAC2), a corepressor important for glucocorticoid action and whose down-regulation is thought to cause glucocorticoid insensitivity in COPD. Treating epithelial cells with synthetic (rosiglitazone) or endogenous (10-nitro-oleic acid) PPARγ agonists strongly up-regulated PPARγ expression and activity, suppressed CSE-induced production and secretion of inflammatory cytokines, and reversed its activation of NF-κB by inhibiting the IκB kinase pathway and by promoting direct inhibitory binding of PPARγ to NF-κB. In contrast, PPARγ knockdown via siRNA augmented CSE-induced chemokine release and decreases in HDAC activity, suggesting a potential anti-inflammatory role of endogenous PPARγ. The results imply that down-regulation of pulmonary epithelial PPARγ by cigarette smoke promotes inflammatory pathways and diminishes glucocorticoid responsiveness, thereby contributing to COPD pathogenesis, and further suggest that PPARγ agonists may be useful for COPD treatment.

  17. Epigenetic regulator Lid maintains germline stem cells through regulating JAK-STAT signaling pathway activity

    PubMed Central

    Tarayrah, Lama; Li, Yuping; Gan, Qiang; Chen, Xin

    2015-01-01

    ABSTRACT Signaling pathways and epigenetic mechanisms have both been shown to play essential roles in regulating stem cell activity. While the role of either mechanism in this regulation is well established in multiple stem cell lineages, how the two mechanisms interact to regulate stem cell activity is not as well understood. Here we report that in the Drosophila testis, an H3K4me3-specific histone demethylase encoded by little imaginal discs (lid) maintains germline stem cell (GSC) mitotic index and prevents GSC premature differentiation. Lid is required in germ cells for proper expression of the Stat92E transcription factor, the downstream effector of the Janus kinase signal transducer and activator of transcription (JAK-STAT) signaling pathway. Our findings support a germ cell autonomous role for the JAK-STAT pathway in maintaining GSCs and place Lid as an upstream regulator of this pathway. Our study provides new insights into the biological functions of a histone demethylase in vivo and sheds light on the interaction between epigenetic mechanisms and signaling pathways in regulating stem cell activities. PMID:26490676

  18. Phosphatidylinositol-3-kinase regulates PKCtheta activity in cytotoxic T cells.

    PubMed

    Puente, Lawrence G; Mireau, Laura R; Lysechko, Tara L; Ostergaard, Hanne L

    2005-06-01

    Protein kinase C (PKC) theta plays a crucial role in T cell activation. We, therefore, examined the regulation of PKCtheta activity in cytotoxic T lymphocytes (CTL). We demonstrated that PMA did not stimulate PKCtheta activation and phospholipase C inhibition did not block anti-CD3-stimulated PKCtheta activation in a CTL clone. This suggests that diacylglycerol is neither sufficient nor required for PKCtheta activation. Furthermore, PKCtheta was only activated in a CTL clone stimulated with plate-bound anti-CD3 but not soluble anti-CD3. However, PMA or cross-linked anti-CD3 stimulated phosphorylation of PKCtheta as measured by a migratory shift, suggesting that phosphorylation was not sufficient for activity. Phosphatidylinositol 3-kinase activity was required for anti-CD3, but not PMA, stimulated phosphorylation and for immobilized anti-CD3-triggered PKCtheta activity. A substantial fraction of PKCtheta was constitutively membrane associated and PMA or CD3 stimulation did not significantly increase membrane association. Our data indicate that phosphorylation of PKCtheta is not a suitable surrogate measurement for PKCtheta activity and that additional, yet to be defined steps, are required for the regulation of PKCtheta enzymatic activity in CTL.

  19. Trypanosoma carassii hsp70 increases expression of inflammatory cytokines and chemokines in macrophages of the goldfish (Carassius auratus L.).

    PubMed

    Oladiran, Ayoola; Belosevic, Miodrag

    2009-10-01

    We report on the cloning and characterization of Trypanosoma carassii 70 KDa heat shock protein (hsp70). T. carassii hsp70 was secreted/excreted into culture medium in vitro and was recognized by sera from infected fish. Recombinant hsp70 (rhsp70) activated goldfish macrophages and stimulated the production of pro-inflammatory cytokines including interferon gamma (IFNgamma), tumor necrosis factor (TNF)-alpha, interleukin (IL)-1beta, (IL)-12 and chemokines CCL-1 and CXCL-8 (IL-8). T. carassii hsp70-induced cytokine expression was abrogated by pronase treatment of macrophages confirming the existence of receptor(s) on goldfish macrophage surface that recognize parasite molecule. Parasite hsp70 also up-regulated the expression inducible nitric oxide synthase (iNOS) isoforms A and B and induced a strong nitric oxide response of goldfish macrophages. PMID:19527750

  20. NKT cells mediate the recruitment of neutrophils by stimulating epithelial chemokine secretion during colitis.

    PubMed

    Huang, Enyu; Liu, Ronghua; Lu, Zhou; Liu, Jiajing; Liu, Xiaoming; Zhang, Dan; Chu, Yiwei

    2016-05-27

    Ulcerative colitis (UC) is a kind of inflammatory bowel diseases characterized by chronic inflammation and ulcer in colon, and UC patients have increased risk of getting colorectal cancer. NKT cells are cells that express both NK cell markers and semi-invariant CD1d-restricted TCRs, can regulate immune responses via secreting a variety of cytokines upon activation. In our research, we found that the NKT cell-deficient CD1d(-/-) mice had relieved colitis in the DSS-induced colitis model. Further investigations revealed that the colon of CD1d(-/-) mice expressed less neutrophil-attracting chemokine CXCL 1, 2 and 3, and had decreased neutrophil infiltration. Infiltrated neutrophils also produced less reactive oxygen species (ROS) and TNF-α, indicating they may cause less epithelial damage. In addition, colitis-associated colorectal cancer was also relieved in CD1d(-/-) mice. During colitis, NKT cells strongly expressed TNF-α, which could stimulate CXCL 1, 2, 3 expressions by the epithelium. In conclusion, NKT cells can regulate colitis via the NKT cell-epithelium-neutrophil axis. Targeting this mechanism may help to improve the therapy of UC and prevent colitis-associated colorectal cancer. PMID:27063801

  1. Ikkepsilon regulates viral-induced interferon regulatory factor-3 activation via a redox-sensitive pathway

    SciTech Connect

    Indukuri, Hemalatha; Castro, Shawn M.; Liao, S.-M.; Feeney, Lee Ann; Dorsch, Marion; Coyle, Anthony J.; Garofalo, Roberto P.; Brasier, Allan R.; Casola, Antonella . E-mail: ancasola@utmb.edu

    2006-09-15

    Respiratory syncytial virus (RSV)-induced chemokine gene expression occurs through the activation of a subset of transcription factors, including Interferon Regulatory Factor (IRF)-3. In this study, we have investigated the signaling pathway leading to RSV-induced IRF-3 activation and whether it is mediated by intracellular reactive oxygen species (ROS) generation. Our results show that RSV infection induces expression and catalytic activity of IKK{epsilon}, a noncanonical IKK-like kinase. Expression of a kinase-inactive IKK{epsilon} blocks RSV-induced IRF-3 serine phosphorylation, nuclear translocation and DNA-binding, leading to inhibition of RANTES gene transcription, mRNA expression and protein synthesis. Treatment of alveolar epithelial cells with antioxidants or with NAD(P)H oxidase inhibitors abrogates RSV-induced chemokine secretion, IRF-3 phosphorylation and IKK{epsilon} induction, indicating that ROS generation plays a fundamental role in the signaling pathway leading to IRF-3 activation, therefore, identifying a novel molecular target for the development of strategies aimed to modify the inflammatory response associated with RSV infection of the lung.

  2. Extracellular Matrix Stiffness Regulates Osteogenic Differentiation through MAPK Activation

    PubMed Central

    Hwang, Jun-Ha; Byun, Mi Ran; Kim, A. Rum; Kim, Kyung Min; Cho, Hang Jun; Lee, Yo Han; Kim, Juwon; Jeong, Mi Gyeong; Hwang, Eun Sook; Hong, Jeong-Ho

    2015-01-01

    Mesenchymal stem cell (MSC) differentiation is regulated by the extracellular matrix (ECM) through activation of intracellular signaling mediators. The stiffness of the ECM was shown to be an important regulatory factor for MSC differentiation, and transcriptional coactivator with PDZ-binding motif (TAZ) was identified as an effector protein for MSC differentiation. However, the detailed underlying mechanism regarding the role of ECM stiffness and TAZ in MSC differentiation is not yet fully understood. In this report, we showed that ECM stiffness regulates MSC fate through ERK or JNK activation. Specifically, a stiff hydrogel matrix stimulates osteogenic differentiation concomitant with increased nuclear localization of TAZ, but inhibits adipogenic differentiation. ERK and JNK activity was significantly increased in cells cultured on a stiff hydrogel. TAZ activation was induced by ERK or JNK activation on a stiff hydrogel because exposure to an ERK or JNK inhibitor significantly decreased the nuclear localization of TAZ, indicating that ECM stiffness-induced ERK or JNK activation is important for TAZ-driven osteogenic differentiation. Taken together, these results suggest that ECM stiffness regulates MSC differentiation through ERK or JNK activation. PMID:26262877

  3. Extracellular Matrix Stiffness Regulates Osteogenic Differentiation through MAPK Activation.

    PubMed

    Hwang, Jun-Ha; Byun, Mi Ran; Kim, A Rum; Kim, Kyung Min; Cho, Hang Jun; Lee, Yo Han; Kim, Juwon; Jeong, Mi Gyeong; Hwang, Eun Sook; Hong, Jeong-Ho

    2015-01-01

    Mesenchymal stem cell (MSC) differentiation is regulated by the extracellular matrix (ECM) through activation of intracellular signaling mediators. The stiffness of the ECM was shown to be an important regulatory factor for MSC differentiation, and transcriptional coactivator with PDZ-binding motif (TAZ) was identified as an effector protein for MSC differentiation. However, the detailed underlying mechanism regarding the role of ECM stiffness and TAZ in MSC differentiation is not yet fully understood. In this report, we showed that ECM stiffness regulates MSC fate through ERK or JNK activation. Specifically, a stiff hydrogel matrix stimulates osteogenic differentiation concomitant with increased nuclear localization of TAZ, but inhibits adipogenic differentiation. ERK and JNK activity was significantly increased in cells cultured on a stiff hydrogel. TAZ activation was induced by ERK or JNK activation on a stiff hydrogel because exposure to an ERK or JNK inhibitor significantly decreased the nuclear localization of TAZ, indicating that ECM stiffness-induced ERK or JNK activation is important for TAZ-driven osteogenic differentiation. Taken together, these results suggest that ECM stiffness regulates MSC differentiation through ERK or JNK activation.

  4. Minimal regulation of platelet activity by PECAM-1.

    PubMed

    Dhanjal, Tarvinder S; Ross, Ewan A; Auger, Jocelyn M; McCarty, Owen J T; Hughes, Craig E; Senis, Yotis A; Buckley, Chris D; Watson, Steve P

    2007-02-01

    PECAM-1 is a member of the superfamily of immunoglobulins (Ig) and is expressed on platelets at moderate level. PECAM-1 has been reported to have contrasting effects on platelet activation by the collagen receptor GPVI and the integrin, alphaIIbbeta3, even though both receptors signal through Src-kinase regulation of PLCgamma2. The present study compares the role of PECAM-1 on platelet activation by these two receptors and by the lectin receptor, CLEC-2, which also signals via PLCgamma2. Studies using PECAM-1 knockout-mice and cross-linking of PECAM-1 using specific antibodies demonstrated a minor inhibitory role on platelet responses to the above three receptors and also under some conditions to the G-protein agonist thrombin. The degree of inhibition was considerably less than that produced by PGI2, which elevates cAMP. There was no significant difference in thrombus formation on collagen in PECAM-1-/- platelets relative to litter-matched controls. The very weak inhibitory effect of PECAM-1 on platelet activation relative to that of PGI2 indicate that the Ig-receptor is not a major regulator of platelet activation. PECAM-1 has been reported to have contrasting effects on platelet activation. The present study demonstrates a very mild or negligible effect on platelet activation in response to stimulation by a variety of agonists, thereby questioning the physiological role of the immunoglobulin receptor as a major regulator of platelet activation. PMID:17365855

  5. Signal transmission through the CXC chemokine receptor 4 (CXCR4) transmembrane helices.

    PubMed

    Wescott, Melanie P; Kufareva, Irina; Paes, Cheryl; Goodman, Jason R; Thaker, Yana; Puffer, Bridget A; Berdougo, Eli; Rucker, Joseph B; Handel, Tracy M; Doranz, Benjamin J

    2016-08-30

    The atomic-level mechanisms by which G protein-coupled receptors (GPCRs) transmit extracellular ligand binding events through their transmembrane helices to activate intracellular G proteins remain unclear. Using a comprehensive library of mutations covering all 352 residues of the GPCR CXC chemokine receptor 4 (CXCR4), we identified 41 amino acids that are required for signaling induced by the chemokine ligand CXCL12 (stromal cell-derived factor 1). CXCR4 variants with each of these mutations do not signal properly but remain folded, based on receptor surface trafficking, reactivity to conformationally sensitive monoclonal antibodies, and ligand binding. When visualized on the structure of CXCR4, the majority of these residues form a continuous intramolecular signaling chain through the transmembrane helices; this chain connects chemokine binding residues on the extracellular side of CXCR4 to G protein-coupling residues on its intracellular side. Integrated into a cohesive model of signal transmission, these CXCR4 residues cluster into five functional groups that mediate (i) chemokine engagement, (ii) signal initiation, (iii) signal propagation, (iv) microswitch activation, and (v) G protein coupling. Propagation of the signal passes through a "hydrophobic bridge" on helix VI that coordinates with nearly every known GPCR signaling motif. Our results agree with known conserved mechanisms of GPCR activation and significantly expand on understanding the structural principles of CXCR4 signaling. PMID:27543332

  6. Cells on the run: shear-regulated integrin activation in leukocyte rolling and arrest on endothelial cells.

    PubMed

    Alon, Ronen; Ley, Klaus

    2008-10-01

    The arrest of rolling leukocytes on various target vascular beds is mediated by specialized leukocyte integrins and their endothelial immunoglobulin superfamily (IgSF) ligands. These integrins are kept in largely inactive states and undergo in situ activation upon leukocyte-endothelial contact by both biochemical and mechanical signals from flow-derived shear forces. In vivo and in vitro studies suggest that leukocyte integrin activation involves conformational alterations through inside-out signaling followed by ligand-induced rearrangements accelerated by external forces. This activation process takes place within fractions of seconds by in situ signals transduced to the rolling leukocyte as it encounters specialized endothelial-displayed chemoattractants, collectively termed arrest chemokines. In neutrophils, selectin rolling engagements trigger intermediate affinity integrins to support reversible adhesions before chemokine-triggered arrest. Different leukocyte subsets appear to use different modalities of integrin activation during rolling and arrest at distinct endothelial sites.

  7. Spectrin regulates Hippo signaling by modulating cortical actomyosin activity

    PubMed Central

    Deng, Hua; Wang, Wei; Yu, Jianzhong; Zheng, Yonggang; Qing, Yun; Pan, Duojia

    2015-01-01

    The Hippo pathway controls tissue growth through a core kinase cascade that impinges on the transcription of growth-regulatory genes. Understanding how this pathway is regulated in development remains a major challenge. Recent studies suggested that Hippo signaling can be modulated by cytoskeletal tension through a Rok-myosin II pathway. How cytoskeletal tension is regulated or its relationship to the other known upstream regulators of the Hippo pathway remains poorly defined. In this study, we identify spectrin, a contractile protein at the cytoskeleton-membrane interface, as an upstream regulator of the Hippo signaling pathway. We show that, in contrast to canonical upstream regulators such as Crumbs, Kibra, Expanded, and Merlin, spectrin regulates Hippo signaling in a distinct way by modulating cortical actomyosin activity through non-muscle myosin II. These results uncover an essential mediator of Hippo signaling by cytoskeleton tension, providing a new entry point to dissecting how mechanical signals regulate Hippo signaling in living tissues. DOI: http://dx.doi.org/10.7554/eLife.06567.001 PMID:25826608

  8. Regulation of APC Activity by Phosphorylation and Regulatory Factors

    PubMed Central

    Kotani, Shuji; Tanaka, Hirofumi; Yasuda, Hideyo; Todokoro, Kazuo

    1999-01-01

    Ubiquitin-dependent proteolysis of Cut2/Pds1 and Cyclin B is required for sister chromatid separation and exit from mitosis, respectively. Anaphase-promoting complex/cyclosome (APC) specifically ubiquitinates Cut2/Pds1 at metaphase–anaphase transition, and ubiquitinates Cyclin B in late mitosis and G1 phase. However, the exact regulatory mechanism of substrate-specific activation of mammalian APC with the right timing remains to be elucidated. We found that not only the binding of the activators Cdc20 and Cdh1 and the inhibitor Mad2 to APC, but also the phosphorylation of Cdc20 and Cdh1 by Cdc2-Cyclin B and that of APC by Polo-like kinase and cAMP-dependent protein kinase, regulate APC activity. The cooperation of the phosphorylation/dephosphorylation and the regulatory factors in regulation of APC activity may thus control the precise progression of mitosis. PMID:10459014

  9. Active Inference, homeostatic regulation and adaptive behavioural control

    PubMed Central

    Pezzulo, Giovanni; Rigoli, Francesco; Friston, Karl

    2015-01-01

    We review a theory of homeostatic regulation and adaptive behavioural control within the Active Inference framework. Our aim is to connect two research streams that are usually considered independently; namely, Active Inference and associative learning theories of animal behaviour. The former uses a probabilistic (Bayesian) formulation of perception and action, while the latter calls on multiple (Pavlovian, habitual, goal-directed) processes for homeostatic and behavioural control. We offer a synthesis these classical processes and cast them as successive hierarchical contextualisations of sensorimotor constructs, using the generative models that underpin Active Inference. This dissolves any apparent mechanistic distinction between the optimization processes that mediate classical control or learning. Furthermore, we generalize the scope of Active Inference by emphasizing interoceptive inference and homeostatic regulation. The ensuing homeostatic (or allostatic) perspective provides an intuitive explanation for how priors act as drives or goals to enslave action, and emphasises the embodied nature of inference. PMID:26365173

  10. Active Inference, homeostatic regulation and adaptive behavioural control.

    PubMed

    Pezzulo, Giovanni; Rigoli, Francesco; Friston, Karl

    2015-11-01

    We review a theory of homeostatic regulation and adaptive behavioural control within the Active Inference framework. Our aim is to connect two research streams that are usually considered independently; namely, Active Inference and associative learning theories of animal behaviour. The former uses a probabilistic (Bayesian) formulation of perception and action, while the latter calls on multiple (Pavlovian, habitual, goal-directed) processes for homeostatic and behavioural control. We offer a synthesis these classical processes and cast them as successive hierarchical contextualisations of sensorimotor constructs, using the generative models that underpin Active Inference. This dissolves any apparent mechanistic distinction between the optimization processes that mediate classical control or learning. Furthermore, we generalize the scope of Active Inference by emphasizing interoceptive inference and homeostatic regulation. The ensuing homeostatic (or allostatic) perspective provides an intuitive explanation for how priors act as drives or goals to enslave action, and emphasises the embodied nature of inference. PMID:26365173

  11. The Chemokine MIP-1α/CCL3 impairs mouse hippocampal synaptic transmission, plasticity and memory

    PubMed Central

    Marciniak, Elodie; Faivre, Emilie; Dutar, Patrick; Alves Pires, Claire; Demeyer, Dominique; Caillierez, Raphaëlle; Laloux, Charlotte; Buée, Luc; Blum, David; Humez, Sandrine

    2015-01-01

    Chemokines are signaling molecules playing an important role in immune regulations. They are also thought to regulate brain development, neurogenesis and neuroendocrine functions. While chemokine upsurge has been associated with conditions characterized with cognitive impairments, their ability to modulate synaptic plasticity remains ill-defined. In the present study, we specifically evaluated the effects of MIP1-α/CCL3 towards hippocampal synaptic transmission, plasticity and spatial memory. We found that CCL3 (50 ng/ml) significantly reduced basal synaptic transmission at the Schaffer collateral-CA1 synapse without affecting NMDAR-mediated field potentials. This effect was ascribed to post-synaptic regulations, as CCL3 did not impact paired-pulse facilitation. While CCL3 did not modulate long-term depression (LTD), it significantly impaired long-term potentiation (LTP), an effect abolished by Maraviroc, a CCR5 specific antagonist. In addition, sub-chronic intracerebroventricular (icv) injections of CCL3 also impair LTP. In accordance with these electrophysiological findings, we demonstrated that the icv injection of CCL3 in mouse significantly impaired spatial memory abilities and long-term memory measured using the two-step Y-maze and passive avoidance tasks. These effects of CCL3 on memory were inhibited by Maraviroc. Altogether, these data suggest that the chemokine CCL3 is an hippocampal neuromodulator able to regulate synaptic plasticity mechanisms involved in learning and memory functions. PMID:26511387

  12. Susceptibility of juvenile and adult blood–brain barrier to endothelin-1: regulation of P-glycoprotein and breast cancer resistance protein expression and transport activity

    PubMed Central

    2012-01-01

    Background P-glycoprotein (P-gp) and breast cancer resistance protein (BCRP) play a critical role in keeping neurotoxic substances from entering the brain. We and others have previously reported an impact of inflammation on the regulation of adult blood–brain barrier (BBB) efflux transporters. However, studies in children have not been done. From the pediatric clinical perspective, it is important to understand how the central nervous system (CNS) and BBB drug efflux transporters differ in childhood from those of adults under normal and inflammatory conditions. Therefore, we examined and compared the regulation of P-gp and BCRP expression and transport activity in young and adult BBB and investigated the molecular mechanisms underlying inflammatory responses. Methods Rats at postnatal day (P) P21 and P84, corresponding to the juvenile and adult stages of human brain maturation, respectively, were treated with endothelin-1 (ET-1) given by the intracerebroventricular (icv) route. Twenty-four hours later, we measured P-gp and BCRP protein expression in isolated brain capillary by immunoblotting as well as by transport activity in vivo by measuring the unbound drug partitioning coefficient of the brain (Kp,uu,brain) of known efflux transporter substrates administered intravenously. Glial activation was measured by immunohistochemistry. The release of cytokines/chemokines (interleukins-1α, 1-β (IL-1β), -6 (IL-6), -10 (IL-10), monocyte chemoattractant protein (MCP-1/CCL2), fractalkine and tissue inhibitor of metalloproteinases-1 (TIMP-1)) were simultaneously measured in brain and serum samples using the Agilent Technology cytokine microarray. Results We found that juvenile and adult BBBs exhibited similar P-gp and BCRP transport activities in the normal physiological conditions. However, long-term exposure of the juvenile brain to low-dose of ET-1 did not change BBB P-gp transport activity but tended to decrease BCRP transport activity in the juvenile brain, while a

  13. Modulation of chemokine gradients by apheresis redirects leukocyte trafficking to different compartments during sepsis, studies in a rat model

    PubMed Central

    2014-01-01

    Introduction Prior work suggests that leukocyte trafficking is determined by local chemokine gradients between the nidus of infection and the plasma. We recently demonstrated that therapeutic apheresis can alter immune mediator concentrations in the plasma, protect against organ injury, and improve survival. Here we aimed to determine whether the removal of chemokines from the plasma by apheresis in experimental peritonitis changes chemokine gradients and subsequently enhances leukocyte localization into the infected compartment, and away from healthy tissues. Methods In total, 76 male adult Sprague–Dawley rats weighing 400 g to 600 g were included in this study. Eighteen hours after inducing sepsis by cecal ligation and puncture, we randomized these rats to apheresis or sham treatment for 4 hours. Cytokines, chemokines, and leukocyte counts from blood, peritoneal cavity, and lung were measured. In a separate experiment, we labeled neutrophils from septic donor animals and injected them into either apheresis or sham-treated animals. All numeric data with normal distributions were compared with one-way analysis of variance, and numeric data not normally distributed were compared with the Mann–Whitney U test. Results Apheresis significantly removed plasma cytokines and chemokines, increased peritoneal fluid-to-blood chemokine (C-X-C motif ligand 1, ligand 2, and C-C motif ligand 2) ratios, and decreased bronchoalveolar lavage fluid-to-blood chemokine ratios, resulting in enhanced leukocyte recruitment into the peritoneal cavity and improved bacterial clearance, but decreased recruitment into the lung. Apheresis also reduced myeloperoxidase activity and histologic injury in the lung, liver, and kidney. These Labeled donor neutrophils exhibited decreased localization in the lung when infused into apheresis-treated animals. Conclusions Our results support the concept of chemokine gradient control of leukocyte trafficking and demonstrate the efficacy of apheresis

  14. Neural progenitor cells regulate microglia functions and activity.

    PubMed

    Mosher, Kira I; Andres, Robert H; Fukuhara, Takeshi; Bieri, Gregor; Hasegawa-Moriyama, Maiko; He, Yingbo; Guzman, Raphael; Wyss-Coray, Tony

    2012-11-01

    We found mouse neural progenitor cells (NPCs) to have a secretory protein profile distinct from other brain cells and to modulate microglial activation, proliferation and phagocytosis. NPC-derived vascular endothelial growth factor was necessary and sufficient to exert at least some of these effects in mice. Thus, neural precursor cells may not only be shaped by microglia, but also regulate microglia functions and activity.

  15. Redirection of doublecortin-positive cell migration by over-expression of the chemokines MCP-1, MIP-1α and GRO-α in the adult rat brain.

    PubMed

    Tang, S K; Knobloch, R A; Maucksch, C; Connor, B

    2014-02-28

    Inflammation-induced chemoattraction plays a major role in adult subventricular zone (SVZ)-derived precursor cell migration following neural cell loss, in particular through the release of chemokines by activated microglia and macrophages. We previously demonstrated that monocyte chemotactic protein-1 (MCP-1) (chemokine (c-c motif) ligand (CCL)2), macrophage inflammatory protein-1α (MIP-1α) (CCL3) and growth regulatory protein-α (GRO-α) (chemokine (c-x-c motif) ligand (CXCL)1) are up-regulated following neural cell loss in the adult striatum and act as potent chemoattractants for SVZ-derived precursor cells in vitro. Based on these observations, the current study aimed to examine the individual effect of MCP-1, MIP-1α and GRO-α on the migration of adult SVZ-derived neural precursor cells in vivo. To address this without the confounding effects of injury-induced chemotactic cues, adeno-associated viral (AAV)2-mediated in vivo gene transfer was used to ectopically express either MCP-1, MIP-1α or GRO-α, or the control red fluorescent protein (RFP) in the normal adult rat striatum. The extent of doublecortin (Dcx)-positive cell recruitment from the SVZ into the striatal parenchyma was then determined at 4 and 8weeks following AAV2 injection. Ectopic expression either of MCP-1 or MIP-1α in the normal adult rat brain significantly increased the number of Dcx-positive cells and the extent of their migration into the striatum at both 4 and 8weeks after vector injection but did not promote either precursor cell proliferation or neural differentiation. In contrast, while over-expression of GRO-α 4weeks after vector injection induced a significant increase in Dcx-positive cell migration compared to control, this effect was reduced to control levels by 8weeks post injection. Further, direct comparison between MCP-1, MIP-1α and GRO-α at both 4 and 8weeks post vector injection indicated that GRO-α may have a reduced effect in inducing Dcx-positive cell migration

  16. Regulation of p53 and MDM2 Activity by MTBP

    PubMed Central

    Brady, Mark; Vlatković, Nikolina; Boyd, Mark T.

    2005-01-01

    p53 is a critical coordinator of a wide range of stress responses. To facilitate a rapid response to stress, p53 is produced constitutively but is negatively regulated by MDM2. MDM2 can inhibit p53 in multiple independent ways: by binding to its transcription activation domain, inhibiting p53 acetylation, promoting nuclear export, and probably most importantly by promoting proteasomal degradation of p53. The latter is achieved via MDM2's E3 ubiquitin ligase activity harbored within the MDM2 RING finger domain. We have discovered that MTBP promotes MDM2-mediated ubiquitination and degradation of p53 and also MDM2 stabilization in an MDM2 RING finger-dependent manner. Moreover, using small interfering RNA to down-regulate endogenous MTBP in unstressed cells, we have found that MTBP significantly contributes to MDM2-mediated regulation of p53 levels and activity. However, following exposure of cells to UV, but not γ-irradiation, MTBP is destabilized as part of the coordinated cellular response. Our findings suggest that MTBP differentially regulates the E3 ubiquitin ligase activity of MDM2 towards two of its most critical targets (itself and p53) and in doing so significantly contributes to MDM2-dependent p53 homeostasis in unstressed cells. PMID:15632057

  17. 15 CFR 922.193 - Prohibited or otherwise regulated activities.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... Sanctuary and Underwater Preserve § 922.193 Prohibited or otherwise regulated activities. (a) Except as..., destroying, possessing, or attempting to recover, alter, destroy, or possess an underwater cultural resource. (2) Drilling into, dredging or otherwise altering the lakebottom associated with underwater...

  18. 76 FR 19120 - Agency Information Collection Activities: Drawback Process Regulations

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-04-06

    ... SECURITY U.S. Customs and Border Protection Agency Information Collection Activities: Drawback Process... Drawback Process Regulations (CBP Forms 7551, 7552 and 7553). This request for comment is being made... CBP is soliciting comments concerning the following information collection: Title: Drawback...

  19. 76 FR 44350 - Agency Information Collection Activities: Drawback Process Regulations

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-07-25

    ... collection was previously published in the Federal Register (76 FR 19120) on April 6, 2011, allowing for a 60... SECURITY U.S. CUSTOMS AND BORDER PROTECTION Agency Information Collection Activities: Drawback Process... approval in accordance with the Paperwork Reduction Act: Drawback Process Regulations (CBP Forms 7551,...

  20. Signal integration by Ca2+ regulates intestinal stem cell activity

    PubMed Central

    Deng, Hansong; Gerencser, Akos A.; Jasper, Heinrich

    2015-01-01

    Summary Somatic stem cells (SCs) maintain tissue homeostasis by dynamically adjusting proliferation and differentiation in response to stress and metabolic cues. Here, we identify Ca2+ signaling as a central regulator of intestinal SC (ISC) activity in Drosophila. We find that dietary L-glutamate stimulates ISC division and gut growth. The metabotropic glutamate receptor (mGluR) is required in ISCs for this response and for an associated modulation of cytosolic Ca2+ oscillations that results in sustained high cytosolic Ca2+ concentrations. High cytosolic Ca2+ induces ISC proliferation by regulating Calcineurin and CREB - regulated transcriptional co-activator (CRTC). In response to a wide range of dietary and stress stimuli, ISCs reversibly transition between Ca2+ oscillation states that represent poised or activated modes of proliferation, respectively. We propose that the dynamic regulation of intracellular Ca2+ levels allows effective integration of diverse mitogenic signals in ISCs to tailor their proliferative activity to the needs of the tissue. PMID:26633624

  1. 76 FR 28801 - Agency Information Collection Activities: Bonded Warehouse Regulations

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-05-18

    ... Federal Register (76 FR 11254) on March 1, 2011, allowing for a 60-day comment period. This notice allows... SECURITY U.S. Customs and Border Protection Agency Information Collection Activities: Bonded Warehouse... approval in accordance with the Paperwork Reduction Act: Bonded Warehouse Regulations. This is a...

  2. Platelets and their chemokines in atherosclerosis—clinical applications

    PubMed Central

    von Hundelshausen, Philipp; Schmitt, Martin M. N.

    2014-01-01

    The concept of platelets as important players in the process of atherogenesis has become increasingly accepted due to accumulating experimental and clinical evidence. Despite the progress in understanding the molecular details of atherosclerosis, particularly by using animal models, the inflammatory and thrombotic roles of activated platelet s especially in the human system remain difficult to dissect, as often only the complications of atherosclerosis, i.e., stroke and myocardial infarction are definable but not the plaque burden. Platelet indices including platelet count and mean platelet volume (MPV) and soluble mediators released by activated platelets are associated with atherosclerosis. The chemokine CXCL4 has multiple atherogenic activities, e.g., altering the differentiation of T cells and macrophages by inhibiting neutrophil and monocyte apoptosis and by increasing the uptake of oxLDL and synergizing with CCL5. CCL5 is released and deposited on endothelium by activated platelets thereby triggering atherogenic monocyte recruitment, which can be attenuated by blocking the corresponding chemokine receptor CCR5. Atheroprotective and plaque stabilizing properties are attributed to CXCL12, which plays an important role in regenerative processes by attracting progenitor cells. Its release from luminal attached platelets accelerates endothelial healing after injury. Platelet surface molecules GPIIb/IIIa, GP1bα, P-selectin, JAM-A and the CD40/CD40L dyade are crucially involved in the interaction with endothelial cells, leukocytes and matrix molecules affecting atherogenesis. Beyond the effects on the arterial inflammatory infiltrate, platelets affect cholesterol metabolism by binding, modifying and endocytosing LDL particles via their scavenger receptors and contribute to the formation of lipid laden macrophages. Current medical therapies for the prevention of atherosclerotic therapies enable the elucidation of mechanisms linking platelets to inflammation and

  3. Characterization of chemokine and chemokine receptor expression during Pneumocystis infection in healthy and immunodeficient mice

    PubMed Central

    Bishop, Lisa R.; Lionakis, Michail S.; Sassi, Monica; Murphy, Philip M.; Hu, Xiaojun; Huang, Da Wei; Sherman, Brad; Qiu, Ju; Yang, Jun; Lempicki, Richard A.; Kovacs, Joseph A.

    2015-01-01

    We examined gene expression levels of multiple chemokines and chemokine receptors during Pneumocystis murina infection in wild-type and immunosuppressed mice, using microarrays and qPCR. In wild-type mice, expression of chemokines that are ligands for Ccr2, Cxcr3, Cxcr6, and Cxcr2 increased at days 32 to 41 post-infection, with a return to baseline by day 75 to 150. Concomitant increases were seen in Ccr2 ,Cxcr3, and Cxcr6, but not in Cxcr2 expression. Induction of these same factors also occurred in CD40-ligand and CD40 knockout mice but only at a much later time-point, during uncontrolled Pneumocystis pneumonia (PCP). Expression of CD4 Th1 markers was increased in wild-type mice during clearance of infection. Ccr2 and Cx3cr1 knockout mice cleared Pneumocystis infection with kinetics similar to wild-type mice, and all animals developed anti-Pneumocystis antibodies. Upregulation of Ccr2, Cxcr3, and Cxcr6 and their ligands supports an important role for T helper cells and mononuclear phagocytes in the clearance of Pneumocystis infection. However, based on the current and prior studies, no single chemokine receptor appears to be critical to the clearance of Pneumocystis. PMID:26052064

  4. Inflammatory Chemokines MIP-1δ and MIP-3α Are Involved in the Migration of Multipotent Mesenchymal Stromal Cells Induced by Hepatoma Cells.

    PubMed

    Lejmi, Esma; Perriraz, Nadja; Clément, Sophie; Morel, Philippe; Baertschiger, Reto; Christofilopoulos, Panayiotis; Meier, Raphael; Bosco, Domenico; Bühler, Léo H; Gonelle-Gispert, Carmen

    2015-05-15

    In vivo, bone marrow-derived multipotent mesenchymal stromal cells (MSC) have been identified at sites of tumors, suggesting that specific signals mobilize and activate MSC to migrate to areas surrounding tumors. The signals and migratory mechanisms that guide MSC are not well understood. Here, we investigated the migration of human MSC induced by conditioned medium of Huh-7 hepatoma cells (Huh-7 CM). Using a transwell migration system, we showed that human MSC migration was increased in the presence of Huh-7 CM. Using a human cytokine antibody array, we detected increased levels of MIP-1δ and MIP-3α in Huh-7 CM. Recombinant chemokines MIP-1δ and MIP-3α induced MSC migration. Anti-MIP-1δ and anti-MIP-3α antibodies added to Huh-7 CM decreased MSC migration, further suggesting that MIP-1δ and MIP-3α were implicated in the Huh-7 CM-induced MSC migration. By real-time polymerase chain reaction, we observed an absence of chemokine receptors CCR2 and CXCR2 and low expression of CCR1, CCR5, and CCR6 in MSC. Expression of these chemokine receptors was not regulated by Huh-7 CM. Furthermore, matrix metalloproteinase 1 (MMP-1) expression was strongly increased in MSC after incubation with Huh-7 CM, suggesting that MSC migration depends on MMP-1 activity. The signaling pathway MAPK/ERK was activated by Huh-7 CM but its inhibition by PD98059 did not impair Huh-7 CM-induced MSC migration. Further, long-term incubation of MSC with MIP-1δ increased α-smooth muscle actin expression, suggesting its implication in the Huh-7 CM-induced evolvement of MSC into myofibroblasts. In conclusion, we report that two inflammatory cytokines, MIP-1δ and MIP-3α, are able to increase MSC migration in vitro. These cytokines might be responsible for migration and evolvement of MSC into myofibroblasts around tumors.

  5. A surface membrane protein of Entamoeba histolytica functions as a receptor for human chemokine IL-8: its role in the attraction of trophozoites to inflammation sites.

    PubMed

    Diaz-Valencia, J Daniel; Pérez-Yépez, Eloy Andrés; Ayala-Sumuano, Jorge Tonatiuh; Franco, Elizabeth; Meza, Isaura

    2015-12-01

    Entamoeba histolytica trophozoites respond to the presence of IL-8, moving by chemotaxis towards the source of the chemokine. IL-8 binds to the trophozoite membrane and triggers a response that activates signaling pathways that in turn regulate actin/myosin cytoskeleton organisation to initiate migration towards the chemokine, suggesting the presence of a receptor for IL-8 in the parasite. Antibodies directed to the human IL-8 receptor (CXCR1) specifically recognised a 29 kDa protein in trophozoite membrane fractions. The same protein was immunoprecipitated by this antibody from total amebic extracts. Peptide analysis of the immunoprecipitated protein revealed a sequence with high homology to a previously identified amebic outer membrane peroxiredoxin and a motif within the third loop of human CXCR1, which is an important site for IL-8 binding and activation of signaling processes. Immunodetection assays demonstrated that the anti-human CXCR1 antibody binds to the 29 kDa protein in a different but close site to where IL-8 binds to the trophozoite surface membrane, suggesting that human and amebic receptors for this chemokine share common epitopes. In the context of the human intestinal environment, a receptor for IL-8 could be a great advantage for E. histolytica trophozoite survival, as they could reach an inflammatory milieu containing abundant nutrients. In addition, it has been suggested that the high content of accessible thiol groups of the protein and its peroxidase activity could provide protection in the oxygen rich milieu of colonic lesions, allowing trophozoite invasion of other tissues and escape from the host immune response.

  6. Cytokines and Chemokines at the Crossroads of Neuroinflammation, Neurodegeneration, and Neuropathic Pain

    PubMed Central

    MacLean, Andrew G.; Philipp, Mario T.

    2013-01-01

    Cytokines and chemokines are proteins that coordinate the immune response throughout the body. The dysregulation of cytokines and chemokines is a central feature in the development of neuroinflammation, neurodegeneration, and demyelination both in the central and peripheral nervous systems and in conditions of neuropathic pain. Pathological states within the nervous system can lead to activation of microglia. The latter may mediate neuronal and glial cell injury and death through production of proinflammatory factors such as cytokines and chemokines. These then help to mobilize the adaptive immune response. Although inflammation may induce beneficial effects such as pathogen clearance and phagocytosis of apoptotic cells, uncontrolled inflammation can result in detrimental outcomes via the production of neurotoxic factors that exacerbate neurodegenerative pathology. In states of prolonged inflammation, continual activation and recruitment of effector cells can establish a feedback loop that perpetuates inflammation and ultimately results in neuronal injury. A critical balance between repair and proinflammatory factors determines the outcome of a neurodegenerative process. This review will focus on how cytokines and chemokines affect neuroinflammation and disease pathogenesis in bacterial meningitis and brain abscesses, Lyme neuroborreliosis, human immunodeficiency virus encephalitis, and neuropathic pain. PMID:23997430

  7. Chemokine signatures in the skin disorders of Lyme borreliosis in Europe: predominance of CXCL9 and CXCL10 in erythema migrans and acrodermatitis and CXCL13 in lymphocytoma.

    PubMed

    Müllegger, Robert R; Means, Terry K; Shin, Junghee J; Lee, Marshall; Jones, Kathryn L; Glickstein, Lisa J; Luster, Andrew D; Steere, Allen C

    2007-09-01

    The three skin disorders of Lyme borreliosis in Europe include erythema migrans, an acute, self-limited lesion; borrelial lymphocytoma, a subacute lesion; and acrodermatitis chronica atrophicans, a chronic lesion. Using quantitative reverse transcription-PCR, we determined mRNA expression of selected chemokines, cytokines, and leukocyte markers in skin samples from 100 patients with erythema migrans, borrelial lymphocytoma, or acrodermatitis chronica atrophicans and from 25 control subjects. Chemokine patterns in lesional skin in each of the three skin disorders included low but significant mRNA levels of the neutrophil chemoattractant CXCL1 and the dendritic cell chemoattractant CCL20 and intermediate levels of the macrophage chemoattractant CCL2. Erythema migrans and particularly acrodermatitis lesions had high mRNA expression of the T-cell-active chemokines CXCL9 and CXCL10 and low levels of the B-cell-active chemokine CXCL13, whereas lymphocytoma lesions had high levels of CXCL13 and lower levels of CXCL9 and CXCL10. This pattern of chemokine expression was consistent with leukocyte marker mRNA in lesional skin. Moreover, using immunohistologic methods, CD3(+) T cells and CXCL9 were visualized in erythema migrans and acrodermatitis lesions, and CD20(+) B cells and CXCL13 were seen in lymphocytoma lesions. Thus, erythema migrans and acrodermatitis chronica atrophicans have high levels of the T-cell-active chemokines CXCL9 and CXCL10, whereas borrelial lymphocytoma has high levels of the B-cell-active chemokine CXCL13.

  8. Chemokine Signatures in the Skin Disorders of Lyme Borreliosis in Europe: Predominance of CXCL9 and CXCL10 in Erythema Migrans and Acrodermatitis and CXCL13 in Lymphocytoma▿

    PubMed Central

    Müllegger, Robert R.; Means, Terry K.; Shin, Junghee J.; Lee, Marshall; Jones, Kathryn L.; Glickstein, Lisa J.; Luster, Andrew D.; Steere, Allen C.

    2007-01-01

    The three skin disorders of Lyme borreliosis in Europe include erythema migrans, an acute, self-limited lesion; borrelial lymphocytoma, a subacute lesion; and acrodermatitis chronica atrophicans, a chronic lesion. Using quantitative reverse transcription-PCR, we determined mRNA expression of selected chemokines, cytokines, and leukocyte markers in skin samples from 100 patients with erythema migrans, borrelial lymphocytoma, or acrodermatitis chronica atrophicans and from 25 control subjects. Chemokine patterns in lesional skin in each of the three skin disorders included low but significant mRNA levels of the neutrophil chemoattractant CXCL1 and the dendritic cell chemoattractant CCL20 and intermediate levels of the macrophage chemoattractant CCL2. Erythema migrans and particularly acrodermatitis lesions had high mRNA expression of the T-cell-active chemokines CXCL9 and CXCL10 and low levels of the B-cell-active chemokine CXCL13, whereas lymphocytoma lesions had high levels of CXCL13 and lower levels of CXCL9 and CXCL10. This pattern of chemokine expression was consistent with leukocyte marker mRNA in lesional skin. Moreover, using immunohistologic methods, CD3+ T cells and CXCL9 were visualized in erythema migrans and acrodermatitis lesions, and CD20+ B cells and CXCL13 were seen in lymphocytoma lesions. Thus, erythema migrans and acrodermatitis chronica atrophicans have high levels of the T-cell-active chemokines CXCL9 and CXCL10, whereas borrelial lymphocytoma has high levels of the B-cell-active chemokine CXCL13. PMID:17606602

  9. Cytokine Regulation of Metastasis and Tumorigenicity.

    PubMed

    Yao, M; Brummer, G; Acevedo, D; Cheng, N

    2016-01-01

    The human body combats infection and promotes wound healing through the remarkable process of inflammation. Inflammation is characterized by the recruitment of stromal cell activity including recruitment of immune cells and induction of angiogenesis. These cellular processes are regulated by a class of soluble molecules called cytokines. Based on function, cell target, and structure, cytokines are subdivided into several classes including: interleukins, chemokines, and lymphokines. While cytokines regulate normal physiological processes, chronic deregulation of cytokine expression and activity contributes to cancer in many ways. Gene polymorphisms of all types of cytokines are associated with risk of disease development. Deregulation RNA and protein expression of interleukins, chemokines, and lymphokines have been detected in many solid tumors and hematopoetic malignancies, correlating with poor patient prognosis. The current body of literature suggests that in some tumor types, interleukins and chemokines work against the human body by signaling to cancer cells and remodeling the local microenvironment to support the growth, survival, and invasion of primary tumors and enhance metastatic colonization. Some lymphokines are downregulated to suppress tumor progression by enhancing cytotoxic T cell activity and inhibiting tumor cell survival. In this review, we will describe the structure/function of several cytokine families and review our current understanding on the roles and mechanisms of cytokines in tumor progression. In addition, we will also discuss strategies for exploiting the expression and activity of cytokines in therapeutic intervention. PMID:27613135

  10. Structural basis of AMPK regulation by small molecule activators

    NASA Astrophysics Data System (ADS)

    Xiao, Bing; Sanders, Matthew J.; Carmena, David; Bright, Nicola J.; Haire, Lesley F.; Underwood, Elizabeth; Patel, Bhakti R.; Heath, Richard B.; Walker, Philip A.; Hallen, Stefan; Giordanetto, Fabrizio; Martin, Stephen R.; Carling, David; Gamblin, Steven J.

    2013-12-01

    AMP-activated protein kinase (AMPK) plays a major role in regulating cellular energy balance by sensing and responding to increases in AMP/ADP concentration relative to ATP. Binding of AMP causes allosteric activation of the enzyme and binding of either AMP or ADP promotes and maintains the phosphorylation of threonine 172 within the activation loop of the kinase. AMPK has attracted widespread interest as a potential therapeutic target for metabolic diseases including type 2 diabetes and, more recently, cancer. A number of direct AMPK activators have been reported as having beneficial effects in treating metabolic diseases, but there has been no structural basis for activator binding to AMPK. Here we present the crystal structure of human AMPK in complex with a small molecule activator that binds at a site between the kinase domain and the carbohydrate-binding module, stabilising the interaction between these two components. The nature of the activator-binding pocket suggests the involvement of an additional, as yet unidentified, metabolite in the physiological regulation of AMPK. Importantly, the structure offers new opportunities for the design of small molecule activators of AMPK for treatment of metabolic disorders.

  11. Src-Mediated EGF Receptor Activation Regulates Ozone-Induced Interleukin 8 Expression in Human Bronchial Epithelial Cells

    PubMed Central

    Wages, Phillip A.; Devlin, Robert B.; Diaz-Sanchez, David; Peden, David B.; Samet, James M.

    2014-01-01

    Background: Human exposure to ozone (O3) results in pulmonary function decrements and airway inflammation. The mechanisms underlying these adverse effects remain unclear. Epidermal growth factor receptor (EGFR) plays an important role in the pathogenesis of lung inflammation. Objective We examined the role of EGFR activation in O3-induced expression of the chemokine interleukin 8 (IL-8) in human bronchial epithelial cells (HBEC). Methods We detected phosphorylated EGFR using immunoblotting. EGFR dimerization was examined through cross-linking reaction and immunoblotting, and levels of IL-8 protein were measured using ELISA. Results Exposure to O3 (0.25–1.0 ppm) induced rapid and marked increase in EGFR phosphorylation at the autophosphorylation site Y1068 and the transphosphorylation site Y845, implicating the involvement of Src kinase. Further investigation showed that O3 stimulation induced phosphorylation of Src at Y416, indicative of Src activation. Pharmacological inhibition of Src kinase activity abrogated O3-induced EGFR phosphorylation at tyrosines 1068 and 845. Moreover, pretreatment of BEAS-2B cells with inhibitor of either EGFR or Src kinase activities significantly blocked O3-induced IL-8 expression. Conclusion Conclusion: O3 exposure increased IL-8 expression through Src-mediated EGFR transactivation in HBEC. Citation> Wu W, Wages PA, Devlin RB, Diaz-Sanchez D, Peden DB, Samet JM. 2015. Src-mediated EGF receptor activation regulates ozone-induced interleukin 8 expression in human bronchial epithelial cells. Environ Health Perspect 123:231–236; http://dx.doi.org/10.1289/ehp.1307379 PMID:25303742

  12. Activity-dependent regulation of astrocyte GAT levels during synaptogenesis

    PubMed Central

    Muthukumar, Allie K.; Stork, Tobias; Freeman, Marc R.

    2014-01-01

    Astrocytic uptake of GABA through GABA transporters (GATs) is an important mechanism regulating excitatory/inhibitory balance in the nervous system, however mechanisms by which astrocytes regulate GAT levels are undefined. Here we show at mid-pupal stages the Drosophila CNS neuropil is devoid of astrocyte membranes and synapses. Astrocyte membranes subsequently infiltrate the neuropil coordinate with synaptogenesis and a strocyte ablation reduces synapse numbers by half, indicating that Drosophila astrocytes are pro-synaptogenic. Shortly after synapses form in earnest, the GABA transporter, GAT, is up-regulated in astrocytes. Ablation or silencing of GABAergic neurons or disruption of metabotropic GABA receptor (GABABR1/2) signaling in astrocytes leads to decreased astrocytic GAT levels. Interestingly, developmental depletion of astrocytic GABABR1/2 signaling suppresses mechanosensory-induced seizure activity in mutants with hyperexcitable neurons. These data reveal astrocytes actively modulate GAT expression via metabotropic GABA receptor signaling, and highlight the importance of precise regulation of astrocytic GAT in modulation of seizure activity. PMID:25151265

  13. Tetraspanin CD9 regulates osteoclastogenesis via regulation of p44/42 MAPK activity

    SciTech Connect

    Yi, TacGhee; Kim, Hye-Jin; Cho, Je-Yoel; Woo, Kyung Mi; Ryoo, Hyun-Mo; Kim, Gwan-Shik; Baek, Jeong-Hwa . E-mail: baekjh@snu.ac.kr

    2006-08-18

    Tetraspanin CD9 has been shown to regulate cell-cell fusion in sperm-egg fusion and myotube formation. However, the role of CD9 in osteoclast, another multinucleated cell type, is not still clear. Therefore, we investigated the role of CD9 in osteoclast differentiation. CD9 was expressed in osteoclast lineage cells and its expression level increased during the progression of RANKL-induced osteoclastogenesis. KMC8, a neutralizing antibody specific to CD9, significantly suppressed RANKL-induced multinucleated osteoclast formation and the mRNA expression of osteoclast differentiation marker genes. To define CD9-regulated osteoclastogenic signaling pathway, MAPK pathways were examined. KMC8 induced long-term phosphorylation of p44/42 MAPK, but not of p38 MAPK. Constitutive activation of p44/42 MAPK by overexpressing constitutive-active mutant of MEK1 almost completely blocked osteoclast differentiation. Taken together, these results suggest that CD9 expressed on osteoclast lineage cells might positively regulate osteoclastogenesis via the regulation of p44/42 MAPK activity.

  14. Regulation of different human NFAT isoforms by neuronal activity.

    PubMed

    Vihma, Hanna; Luhakooder, Mirjam; Pruunsild, Priit; Timmusk, Tõnis

    2016-05-01

    Nuclear factor of activated T-cells (NFAT) is a family of transcription factors comprising four calcium-regulated members: NFATc1, NFATc2, NFATc3, and NFATc4. Upon activation by the calcium-dependent phosphatase calcineurin (CaN), NFATs translocate from cytosol to the nucleus and regulate their target genes, which in the nervous system are involved in axon growth, synaptic plasticity, and neuronal survival. We have shown previously that there are a number of different splice variants of NFAT genes expressed in the brain. Here, we studied the subcellular localizations and transactivation capacities of alternative human NFAT isoforms in rat primary cortical or hippocampal neurons in response to membrane depolarization and compared the induced transactivation levels in neurons to those obtained from HEK293 cells in response to calcium signaling. We confirm that in neurons the translocation to the nucleus of all NFAT isoforms is reliant on the activity of CaN. However, our results suggest that both the regulation of subcellular localization and transcriptional activity of NFAT proteins in neurons is isoform specific. We show that in primary hippocampal neurons NFATc2 isoforms have very fast translocation kinetics, whereas NFATc4 isoforms translocate relatively slowly to the nucleus. Moreover, we demonstrate that the strongest transcriptional activators in HEK293 cells are NFATc1 and NFATc3, but in neurons NFATc3 and NFATc4 lead to the highest induction, and NFATc2 and NFATc1 display isoform-specific transcription activation capacities. Altogether, our results indicate that the effects of calcium signaling on the action of NFAT proteins are isoform-specific and can differ between cell types. We show that the effects of calcium signaling on the action of NFAT proteins are isoform-specific and differ between cell types. Although nuclear localization of all NFAT isoforms in neurons requires calcineurin, the subcellular distributions, neuronal activity-induced nuclear

  15. Serum amyloid A chemoattracts immature dendritic cells and indirectly provokes monocyte chemotaxis by induction of cooperating CC and CXC chemokines.

    PubMed

    Gouwy, Mieke; De Buck, Mieke; Pörtner, Noëmie; Opdenakker, Ghislain; Proost, Paul; Struyf, Sofie; Van Damme, Jo

    2015-01-01

    Serum amyloid A (SAA) is an acute phase protein that is upregulated in inflammatory diseases and chemoattracts monocytes, lymphocytes, and granulocytes via its G protein-coupled receptor formyl peptide receptor like 1/formyl peptide receptor 2 (FPRL1/FPR2). Here, we demonstrated that the SAA1α isoform also chemoattracts monocyte-derived immature dendritic cells (DCs) in the Boyden and μ-slide chemotaxis assay and that its chemotactic activity for monocytes and DCs was indirectly mediated via rapid chemokine induction. Indeed, SAA1 induced significant amounts (≥5 ng/mL) of macrophage inflammatory protein-1α/CC chemokine ligand 3 (MIP-1α/CCL3) and interleukin-8/CXC chemokine ligand 8 (IL-8/CXCL8) in monocytes and DCs in a dose-dependent manner within 3 h. However, SAA1 also directly activated monocytes and DCs for signaling and chemotaxis without chemokine interference. SAA1-induced monocyte migration was nevertheless significantly prevented (60-80% inhibition) in the constant presence of desensitizing exogenous MIP-1α/CCL3, neutralizing anti-MIP-1α/CCL3 antibody, or a combination of CC chemokine receptor 1 (CCR1) and CCR5 antagonists, indicating that this endogenously produced CC chemokine was indirectly contributing to SAA1-mediated chemotaxis. Further, anti-IL-8/CXCL8 antibody neutralized SAA1-induced monocyte migration, suggesting that endogenous IL-8/CXCL8 acted in concert with MIP-1α/CCL3. This explained why SAA1 failed to synergize with exogenously added MIP-1α/CCL3 or stromal cell-derived factor-1α (SDF-1α)/CXCL12 in monocyte and DC chemotaxis. In addition to direct leukocyte activation, SAA1 induces a chemotactic cascade mediated by expression of cooperating chemokines to prolong leukocyte recruitment to the inflammatory site.

  16. Bassoon and piccolo regulate ubiquitination and link presynaptic molecular dynamics with activity-regulated gene expression.

    PubMed

    Ivanova, Daniela; Dirks, Anika; Fejtova, Anna

    2016-10-01

    Release of neurotransmitter is executed by complex multiprotein machinery, which is assembled around the presynaptic cytomatrix at the active zone. One well-established function of this proteinaceous scaffold is the spatial organization of synaptic vesicle cluster, the protein complexes that execute membrane fusion and compensatory endocytosis, and the transmembrane molecules important for alignment of pre- and postsynaptic structures. The presynaptic cytomatrix proteins function also in processes other than the formation of a static frame for assembly of the release apparatus and synaptic vesicle cycling. They actively contribute to the regulation of multiple steps in this process and are themselves an important subject of regulation during neuronal plasticity. We are only beginning to understand the mechanisms and signalling pathways controlling these regulations. They are mainly dependent on posttranslational modifications, including phosphorylation and small-molecules conjugation, such as ubiquitination. Ubiquitination of presynaptic proteins might lead to their degradation by proteasomes, but evidence is growing that this modification also affects their function independently of their degradation. Signalling from presynapse to nucleus, which works on a much slower time scale and more globally, emerged as an important mechanism for persistent usage-dependent and homeostatic neuronal plasticity. Recently, two new functions for the largest presynaptic scaffolding proteins bassoon and piccolo emerged. They were implied (1) in the regulation of specific protein ubiquitination and proteasome-mediated proteolysis that potentially contributes to short-term plasticity at the presynapse and (2) in the coupling of activity-induced molecular rearrangements at the presynapse with reprogramming of expression of neuronal activity-regulated genes.

  17. CX3CL1/CX3CR1 and CCL2/CCR2 Chemokine/Chemokine Receptor Complex in Patients with AMD

    PubMed Central

    Falk, Mads Krüger; Singh, Amardeep; Faber, Carsten; Nissen, Mogens Holst; Hviid, Thomas; Sørensen, Torben Lykke

    2014-01-01

    Purpose The chemokine receptors CX3CR1 and CCR2 have been implicated in the development of age-related macular degeneration (AMD). The evidence is mainly derived from experimental cell studies and murine models of AMD. The purpose of this study was to investigate the association between expression of CX3CR1 and CCR2 on different leukocyte subsets and AMD. Furthermore we measured the plasma levels of ligands CX3CL1 and CCL2. Methods Patients attending our department were asked to participate in the study. The diagnosis of AMD was based on clinical examination and multimodal imaging techniques. Chemokine plasma level and chemokine receptor expression were measured by flow-cytometry. Results A total of 150 participants were included. We found a significantly lower expression of CX3CR1 on CD8+ T cells in the neovascular AMD group compared to the control group (p = 0.04). We found a significant positive correlation between CCR2 and CX3CR1 expression on CD8+ cells (r = 0.727, p = 0.0001). We found no difference in plasma levels of CX3CL1 and CCL2 among the groups. Conclusions Our results show a down regulation of CX3CR1 on CD8+ cells; this correlated to a low expression of CCR2 on CD8+ cells. Further studies are needed to elucidate the possible role of this cell type in AMD development. PMID:25503251

  18. HIF-1 expression is associated with CCL2 chemokine expression in airway inflammatory cells: implications in allergic airway inflammation

    PubMed Central

    2012-01-01

    Background The pathogenesis of allergic airway inflammation in asthmatic patients is complex and characterized by cellular infiltrates and activity of many cytokines and chemokines. Both the transcription factor hypoxia inducible factor-1 (HIF-1) and chemokine CCL2 have been shown to play pivotal roles in allergic airway inflammation. The interrelationship between these two factors is not known. We hypothesized that the expression of HIF-1 and CCL2 may be correlated and that the expression of CCL2 may be under the regulation of HIF-1. Several lines of evidence are presented to support this hypothesis. Methods The effects of treating wild-type OVA (ovalbumin)-sensitized/challenged mice with ethyl-3,4-dihydroxybenzoate (EDHB), which upregulate HIF, on CCL2 expression, were determined. Mice conditionally knocked out for HIF-1β was examined for their ability to mount an allergic inflammatory response and CCL2 expression in the lung after intratracheal exposure to ovalbumin. The association of HIF-1α and CCL2 levels was also measured in endobronchial biopsies and bronchial fluid of asthma patients after challenge. Results We show that both HIF-1α and CCL2 were upregulated during an OVA (ovalbumin)-induced allergic response in mice. The levels of HIF-1α and CCL2 were significantly increased following treatment with a pharmacological agent which upregulates HIF-1α, ethyl-3,4-dihydroxybenzoate (EDHB). In contrast, the expression levels of HIF-1α and CCL2 were decreased in the lungs of mice that have been conditionally knocked out for ARNT (HIF-1β) following sensitization with OVA when compared to levels in wild type mice. In asthma patients, the levels of HIF-1α and CCL2 increased after challenge with the allergen. Conclusions These data suggest that CCL2 expression is regulated, in part, by HIF-1 in the lung. These findings also demonstrate that both CCL2 and HIF-1 are implicated in the pathogenesis of allergic airway inflammation. PMID:22823210

  19. Dengue virus requires the CC-chemokine receptor CCR5 for replication and infection development.

    PubMed

    Marques, Rafael E; Guabiraba, Rodrigo; Del Sarto, Juliana L; Rocha, Rebeca F; Queiroz, Ana Luiza; Cisalpino, Daniel; Marques, Pedro E; Pacca, Carolina C; Fagundes, Caio T; Menezes, Gustavo B; Nogueira, Maurício L; Souza, Danielle G; Teixeira, Mauro M

    2015-08-01

    Dengue is a mosquito-borne disease that affects millions of people worldwide yearly. Currently, there is no vaccine or specific treatment available. Further investigation on dengue pathogenesis is required to better understand the disease and to identify potential therapeutic targets. The chemokine system has been implicated in dengue pathogenesis, although the specific role of chemokines and their receptors remains elusive. Here we describe the role of the CC-chemokine receptor CCR5 in Dengue virus (DENV-2) infection. In vitro experiments showed that CCR5 is a host factor required for DENV-2 replication in human and mouse macrophages. DENV-2 infection induces the expression of CCR5 ligands. Incubation with an antagonist prevents CCR5 activation and reduces DENV-2 positive-stranded (+) RNA inside macrophages. Using an immunocompetent mouse model of DENV-2 infection we found that CCR5(-/-) mice were resistant to lethal infection, presenting at least 100-fold reduction of viral load in target organs and significant reduction in disease severity. This phenotype was reproduced in wild-type mice treated with CCR5-blocking compounds. Therefore, CCR5 is a host factor required for DENV-2 replication and disease development. Targeting CCR5 might represent a therapeutic strategy for dengue fever. These data bring new insights on the association between viral infections and the chemokine receptor CCR5.

  20. Analysis of Arrestin Recruitment to Chemokine Receptors by Bioluminescence Resonance Energy Transfer.

    PubMed

    Bonneterre, J; Montpas, N; Boularan, C; Galés, C; Heveker, N

    2016-01-01

    Chemokine receptors recruit the multifunctional scaffolding protein beta arrestin in response to binding of their chemokine ligands. Given that arrestin recruitment represents a signaling axis that is in part independent from G-protein signaling, it has become a hallmark of G protein-coupled receptor functional selectivity. Therefore, quantification of arrestin recruitment has become a requirement for the delineation of chemokine and drug candidate activity along different signaling axes. Bioluminescence resonance energy transfer (BRET) techniques provide methodology for such quantification that can reveal differences between nonredundant chemokines binding the same receptor, and that can be upscaled for high-throughput testing. We here provide protocols for the careful setup of BRET-based arrestin recruitment assays, and examples for the application of such systems in dose-response or time-course experiments. Suggestions are given for troubleshooting, optimizing test systems, and the interpretation of results obtained with BRET-based assays, which indeed yield an intricate blend of quantitative and qualitative information.

  1. Role of the platelet chemokine platelet factor 4 (PF4) in hemostasis and thrombosis.

    PubMed

    Kowalska, M Anna; Rauova, Lubica; Poncz, Mortimer

    2010-04-01

    Chemokines are a family of small proteins that have significant roles in inflammation, angiogenesis and cellular homing. Since inflammation and hemostasis/thrombosis have multiple overlapping roles and pathways, one could expect that some chemokines would also have biologically significant roles in hemostasis/thrombosis as well. This would especially be true for chemokines that are localized solely or predominantly within platelets and released in large amounts at sites of platelet activation such as platelet factor 4 (PF4, CXCL4) and its closely related chemokine, platelet basic protein (PBP, CXCL7). Our group and others have clearly demonstrated an in vivo role for PF4 in hemostasis/thrombosis, but not for PBP, which in contrast has clear proinflammatory properties. This review will focus on PF4 and its potential roles in hemostasis/thrombosis and the underlying pathways by which PF4 may be especially important in such pathologic thrombotic states as heparin-induced thrombocytopenia (HIT) and septic shock. PMID:20004006

  2. Interleukin 2 activates extracellular signal-regulated protein kinase 2

    PubMed Central

    1993-01-01

    Interleukin 2 (IL-2) stimulated activation of the 42-kD extracellular signal-regulated kinase 2 (Erk2) in murine IL-3-dependent cells, expressing either high or intermediate affinity IL-2 receptors. Activation was both rapid, occurring within 5 min of IL-2 addition, and prolonged, remaining elevated for 30 min. Activation of Erk2 appeared to be necessary for IL-2 stimulation of proliferation, as deletion of a region of the cytoplasmic domain of the IL-2 receptor beta chain, essential for IL-2 stimulation of proliferation, abolished Erk2 activation by IL-2. Furthermore, cells that had been deprived of cytokine for 24 h were then refractory to IL-2 stimulation of both Erk2 activity and proliferation. However, elevation of Erk2 activity was not sufficient to stimulate proliferation, as protein kinase C activation stimulated Erk2 activity but not DNA synthesis. Also, cells exposed to IL-2 in the presence of rapamycin showed full Erk2 activation but not DNA synthesis. These data suggest that IL-2 must stimulate both Erk2 activity and a further pathway(s) to trigger cell proliferation. PMID:8376945

  3. Alexithymia influences brain activation during emotion perception but not regulation

    PubMed Central

    Gromann, Paula M.; Swart, Marte; Wiersma, Durk; de Haan, Lieuwe; Bruggeman, Richard; Krabbendam, Lydia; Aleman, André

    2015-01-01

    Alexithymia is a psychological construct that can be divided into a cognitive and affective dimension. The cognitive dimension is characterized by difficulties in identifying, verbalizing and analysing feelings. The affective dimension comprises reduced levels of emotional experience and imagination. Alexithymia is widely regarded to arise from an impairment of emotion regulation. This is the first functional magnetic resonance imaging (fMRI) study to critically evaluate this by investigating the neural correlates of emotion regulation as a function of alexithymia levels. The aim of the current study was to investigate the neural correlates underlying the two alexithymia dimensions during emotion perception and emotion regulation. Using fMRI, we scanned 51 healthy subjects while viewing, reappraising or suppressing negative emotional pictures. The results support the idea that cognitive alexithymia, but not affective alexithymia, is associated with lower activation in emotional attention and recognition networks during emotion perception. However, in contrast with several theories, no alexithymia-related differences were found during emotion regulation (neither reappraisal nor suppression). These findings suggest that alexithymia may result from an early emotion processing deficit rather than compromised frontal circuits subserving higher-order emotion regulation processes. PMID:24760016

  4. Pathway-selective suppression of chemokine receptor signaling in B cells by LPS through downregulation of PLC-β2.

    PubMed

    Shirakawa, Aiko-Konno; Liao, Fang; Zhang, Hongwei H; Hedrick, Michael N; Singh, Satya P; Wu, Dianqing; Farber, Joshua M

    2010-11-01

    Lymphocyte activation leads to changes in chemokine receptor expression. There are limited data, however, on how lymphocyte activators can alter chemokine signaling by affecting downstream pathways. We hypothesized that B cell-activating agents might alter chemokine responses by affecting downstream signal transducers, and that such effects might differ depending on the activator. We found that activating mouse B cells using either anti-IgM or lipopolysaccharide (LPS) increased the surface expression of CCR6 and CCR7 with large increases in chemotaxis to their cognate ligands. By contrast, while anti-IgM also led to enhanced calcium responses, LPS-treated cells showed only small changes in calcium signaling as compared with cells that were freshly isolated. Of particular interest, we found that LPS caused a reduction in the level of B-cell phospholipase C (PLC)-β2 mRNA and protein. Data obtained using PLC-β2(-/-) mice showed that the β2 isoform mediates close to one-half the chemokine-induced calcium signal in resting and anti-IgM-activated B cells, and we found that calcium signals in the LPS-treated cells were boosted by increasing the level of PLC-β2 using transfection, consistent with a functional effect of downregulating PLC-β2. Together, our results show activator-specific effects on responses through B-cell chemokine receptors that are mediated by quantitative changes in a downstream signal-transducing protein, revealing an activity for LPS as a downregulator of PLC-β2, and a novel mechanism for controlling chemokine-induced signals in lymphocytes.

  5. Flavonoids as dietary regulators of nuclear receptor activity

    PubMed Central

    Avior, Yishai; Bomze, David; Ramon, Ory

    2013-01-01

    Metabolic diseases such as obesity, type II diabetes, and dyslipidemia are a rising cause of mortality worldwide. The progression of many metabolic diseases is fundamentally regulated on the transcriptional level by a family of ligand-activated transcription factors, called nuclear receptors, which detect and respond to metabolic changes. Their role in maintaining metabolic homeostasis makes nuclear receptors an important pharmaceutical and dietary target. This review will present the growing evidence that flavonoids, natural secondary plant metabolites, are important regulators of nuclear receptor activity. Structural similarities between flavonoids and cholesterol derivatives combined with the promiscuous nature of most nuclear receptors provide a wealth of possibilities for pharmaceutical and dietary modulation of metabolism. While the challenges of bringing flavonoid-derived therapeutics to the market are significant, we consider this rapidly growing field to be an essential aspect of the functional food initiative and an important mine for pharmaceutical compounds. PMID:23598551

  6. Harvester ants use interactions to regulate forager activation and availability

    PubMed Central

    Pinter-Wollman, Noa; Bala, Ashwin; Merrell, Andrew; Queirolo, Jovel; Stumpe, Martin C.; Holmes, Susan; Gordon, Deborah M.

    2013-01-01

    Social groups balance flexibility and robustness in their collective response to environmental changes using feedback between behavioural processes that operate at different timescales. Here we examine how behavioural processes operating at two timescales regulate the foraging activity of colonies of the harvester ant, Pogonomyrmex barbatus, allowing them to balance their response to food availability and predation. Previous work showed that the rate at which foragers return to the nest with food influences the rate at which foragers leave the nest. To investigate how interactions inside the nest link the rates of returning and outgoing foragers, we observed outgoing foragers inside the nest in field colonies using a novel observation method. We found that the interaction rate experienced by outgoing foragers inside the nest corresponded to forager return rate, and that the interactions of outgoing foragers were spatially clustered. Activation of a forager occurred on the timescale of seconds: a forager left the nest 3–8 s after a substantial increase in interactions with returning foragers. The availability of outgoing foragers to become activated was adjusted on the timescale of minutes: when forager return was interrupted for more than 4–5 min, available foragers waiting near the nest entrance went deeper into the nest. Thus, forager activation and forager availability both increased with the rate at which foragers returned to the nest. This process was checked by negative feedback between forager activation and forager availability. Regulation of foraging activation on the timescale of seconds provides flexibility in response to fluctuations in food abundance, whereas regulation of forager availability on the timescale of minutes provides robustness in response to sustained disturbance such as predation. PMID:24031094

  7. Harvester ants use interactions to regulate forager activation and availability.

    PubMed

    Pinter-Wollman, Noa; Bala, Ashwin; Merrell, Andrew; Queirolo, Jovel; Stumpe, Martin C; Holmes, Susan; Gordon, Deborah M

    2013-07-01

    Social groups balance flexibility and robustness in their collective response to environmental changes using feedback between behavioural processes that operate at different timescales. Here we examine how behavioural processes operating at two timescales regulate the foraging activity of colonies of the harvester ant, Pogonomyrmex barbatus, allowing them to balance their response to food availability and predation. Previous work showed that the rate at which foragers return to the nest with food influences the rate at which foragers leave the nest. To investigate how interactions inside the nest link the rates of returning and outgoing foragers, we observed outgoing foragers inside the nest in field colonies using a novel observation method. We found that the interaction rate experienced by outgoing foragers inside the nest corresponded to forager return rate, and that the interactions of outgoing foragers were spatially clustered. Activation of a forager occurred on the timescale of seconds: a forager left the nest 3-8 s after a substantial increase in interactions with returning foragers. The availability of outgoing foragers to become activated was adjusted on the timescale of minutes: when forager return was interrupted for more than 4-5 min, available foragers waiting near the nest entrance went deeper into the nest. Thus, forager activation and forager availability both increased with the rate at which foragers returned to the nest. This process was checked by negative feedback between forager activation and forager availability. Regulation of foraging activation on the timescale of seconds provides flexibility in response to fluctuations in food abundance, whereas regulation of forager availability on the timescale of minutes provides robustness in response to sustained disturbance such as predation.

  8. A Chemokine Expressed in Lymphoid High Endothelial Venules Promotes the Adhesion and Chemotaxis of Naive T Lymphocytes

    NASA Astrophysics Data System (ADS)

    Gunn, Michael D.; Tangemann, Kirsten; Tam, Carmen; Cyster, Jason G.; Rosen, Steven D.; Williams, Lewis T.

    1998-01-01

    Preferential homing of naive lymphocytes to secondary lymphoid organs is thought to involve the action of chemokines, yet no chemokine has been shown to have either the expression pattern or the activities required to mediate this process. Here we show that a chemokine represented in the EST database, secondary lymphoid-tissue chemokine (SLC), is expressed in the high endothelial venules of lymph nodes and Peyer's patches, in the T cell areas of spleen, lymph nodes, and Peyer's patches, and in the lymphatic endothelium of multiple organs. SLC is a highly efficacious chemoattractant for lymphocytes with preferential activity toward naive T cells. Moreover, SLC induces firm adhesion of naive T lymphocytes via β 2 integrin binding to the counter receptor, intercellular adhesion molecule-1, a necessary step for lymphocyte recruitment. SLC is the first chemokine demonstrated to have the characteristics required to mediate homing of lymphocytes to secondary lymphoid organs. In addition, the expression of SLC in lymphatic endothelium suggests that the migration of lymphocytes from tissues into efferent lymphatics may be an active process mediated by this molecule.

  9. Activity-dependent regulation of astrocyte GAT levels during synaptogenesis.

    PubMed

    Muthukumar, Allie K; Stork, Tobias; Freeman, Marc R

    2014-10-01

    Astrocytic uptake of GABA through GABA transporters (GATs) is an important mechanism regulating excitatory/inhibitory balance in the nervous system; however, mechanisms by which astrocytes regulate GAT levels are undefined. We found that at mid-pupal stages the Drosophila melanogaster CNS neuropil was devoid of astrocyte membranes and synapses. Astrocyte membranes subsequently infiltrated the neuropil coordinately with synaptogenesis, and astrocyte ablation reduced synapse numbers by half, indicating that Drosophila astrocytes are pro-synaptogenic. Shortly after synapses formed in earnest, GAT was upregulated in astrocytes. Ablation or silencing of GABAergic neurons or disruption of metabotropic GABA receptor 1 and 2 (GABA(B)R1/2) signaling in astrocytes led to a decrease in astrocytic GAT. Notably, developmental depletion of astrocytic GABA(B)R1/2 signaling suppressed mechanosensory-induced seizure activity in mutants with hyperexcitable neurons. These data reveal that astrocytes actively modulate GAT expression via metabotropic GABA receptor signaling and highlight the importance of precise regulation of astrocytic GAT in modulation of seizure activity.

  10. Disorders of regulation of cognitive activity in autistic children.

    PubMed

    Adrien, J L; Martineau, J; Barthélémy, C; Bruneau, N; Garreau, B; Sauvage, D

    1995-06-01

    Infantile autism is a pervasive developmental disorder characterized by disturbances concerning not only the areas of socialization and communication ("aloneness") but also the ability to modify and change behavior ("need for sameness"). In most recent studies, various abnormal and deviant cognitive activities, such as the ability to regulate one's behavior, were considered as accounting for these signs. In this report, we examined the regulation of cognitive activity, from a developmental perspective in comparing autistic with mentally retarded children matched in a pairwise manner by global, verbal, and nonverbal developmental ages. All children were tested with tasks adapted from the Object Permanence Test which corresponds to Piaget's sensorimotor development Stages IV to VI. Results showed that autistic children had a pervasive difficulty in maintenance set, made more perseverative errors when the abstraction degree of task was higher, and were more variable in their behavioral strategies. Discussion is focused on the interests and limits of these tasks for the examination of regulation activity from diagnostic and developmental perspectives. Finally, interpretations about recent neuropsychological and neurophysiological works, and additional interdisciplinary studies are suggested. PMID:7559291

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

    PubMed

    Matta, Sumit Kumar; Kumar, Dhiraj

    2015-09-01

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

  12. Immunological role of C4 CC chemokine-1 from snakehead murrel Channa striatus.

    PubMed

    Bhatt, Prasanth; Kumaresan, Venkatesh; Palanisamy, Rajesh; Chaurasia, Mukesh Kumar; Gnanam, Annie J; Pasupuleti, Mukesh; Arockiaraj, Jesu

    2014-02-01

    In this study, we have reported a cDNA sequence of C4 CC chemokine identified from snakehead murrel (also known as striped murrel) Channa striatus (named as CsCC-Chem-1) normalized cDNA library constructed by Genome Sequencing FLX™ Technology (GS-FLX™). CsCC-Chem-1 is 641 base pairs (bp) long that contain 438 bp open reading frame (ORF). The ORF encodes a polypeptide of 146 amino acids with a molecular mass of 15 kDa. The polypeptide contains a small cytokine domain at 30-88. The domain carries the CC motif at Cys(33)-Cys(34). In addition, CsCC-Chem-1 consists of another two cysteine residues at C(59) and C(73), which, together with C(33) and C(34), make CsCC-Chem-1 as a C4-CC chemokine. CsCC-Chem-1 also contains a 'TCCT' motif at 32-35 as CC signature motif; this new motif may represent new characteristic features, which may lead to some unknown function that needs to be further focused on. Phylogenitically, CsCC-Chem-1 clustered together with CC-Chem-1 from rock bream Oplegnathus fasciatus and European sea bass Dicentrarchus labrax. Significantly (P<0.05) highest gene expression was noticed in spleen and is up-regulated upon fungus (Aphanomyces invadans), bacteria (Aeromonas hydrophila) and virus (poly I:C) infection at various time points. The gene expression results indicate the influence of CsCC-Chem-1 in the immune system of murrel. Overall, the gene expression study showed that the CsCC-Chem-1 is a capable gene to increase the cellular response against various microbial infections. Further, we cloned the coding sequence of CsCC-Chem-1 in pMAL vector and purified the recombinant protein to study the functional properties. The cell proliferation activity of recombinant CsCC-Chem-1 protein showed a significant metabolic activity in a concentration dependent manner. Moreover, the chemotaxis assay showed the capability of recombinant CsCC-Chem-1 protein which can induce the migration of spleen leukocytes in C. striatus. However, this remains to be verified

  13. Immunological role of C4 CC chemokine-1 from snakehead murrel Channa striatus.

    PubMed

    Bhatt, Prasanth; Kumaresan, Venkatesh; Palanisamy, Rajesh; Chaurasia, Mukesh Kumar; Gnanam, Annie J; Pasupuleti, Mukesh; Arockiaraj, Jesu

    2014-02-01

    In this study, we have reported a cDNA sequence of C4 CC chemokine identified from snakehead murrel (also known as striped murrel) Channa striatus (named as CsCC-Chem-1) normalized cDNA library constructed by Genome Sequencing FLX™ Technology (GS-FLX™). CsCC-Chem-1 is 641 base pairs (bp) long that contain 438 bp open reading frame (ORF). The ORF encodes a polypeptide of 146 amino acids with a molecular mass of 15 kDa. The polypeptide contains a small cytokine domain at 30-88. The domain carries the CC motif at Cys(33)-Cys(34). In addition, CsCC-Chem-1 consists of another two cysteine residues at C(59) and C(73), which, together with C(33) and C(34), make CsCC-Chem-1 as a C4-CC chemokine. CsCC-Chem-1 also contains a 'TCCT' motif at 32-35 as CC signature motif; this new motif may represent new characteristic features, which may lead to some unknown function that needs to be further focused on. Phylogenitically, CsCC-Chem-1 clustered together with CC-Chem-1 from rock bream Oplegnathus fasciatus and European sea bass Dicentrarchus labrax. Significantly (P<0.05) highest gene expression was noticed in spleen and is up-regulated upon fungus (Aphanomyces invadans), bacteria (Aeromonas hydrophila) and virus (poly I:C) infection at various time points. The gene expression results indicate the influence of CsCC-Chem-1 in the immune system of murrel. Overall, the gene expression study showed that the CsCC-Chem-1 is a capable gene to increase the cellular response against various microbial infections. Further, we cloned the coding sequence of CsCC-Chem-1 in pMAL vector and purified the recombinant protein to study the functional properties. The cell proliferation activity of recombinant CsCC-Chem-1 protein showed a significant metabolic activity in a concentration dependent manner. Moreover, the chemotaxis assay showed the capability of recombinant CsCC-Chem-1 protein which can induce the migration of spleen leukocytes in C. striatus. However, this remains to be verified

  14. CC Chemokine Ligand 18 in ANCA-Associated Crescentic GN.

    PubMed

    Brix, Silke R; Stege, Gesa; Disteldorf, Erik; Hoxha, Elion; Krebs, Christian; Krohn, Sonja; Otto, Benjamin; Klätschke, Kristin; Herden, Elisabeth; Heymann, Felix; Lira, Sergio A; Tacke, Frank; Wolf, Gunter; Busch, Martin; Jabs, Wolfram J; Özcan, Fedai; Keller, Frieder; Beige, Joachim; Wagner, Karl; Helmchen, Udo; Noriega, Mercedes; Wiech, Thorsten; Panzer, Ulf; Stahl, Rolf A K

    2015-09-01

    ANCA-associated vasculitis is the most frequent cause of crescentic GN. To define new molecular and/or cellular biomarkers of this disease in the kidney, we performed microarray analyses of renal biopsy samples from patients with ANCA-associated crescentic GN. Expression profiles were correlated with clinical data in a prospective study of patients with renal ANCA disease. CC chemokine ligand 18 (CCL18), acting through CC chemokine receptor 8 (CCR8) on mononuclear cells, was identified as the most upregulated chemotactic cytokine in patients with newly diagnosed ANCA-associated crescentic GN. Macrophages and myeloid dendritic cells in the kidney were detected as CCL18-producing cells. The density of CCL18(+) cells correlated with crescent formation, interstitial inflammation, and impairment of renal function. CCL18 protein levels were higher in sera of patients with renal ANCA disease compared with those in sera of patients with other forms of crescentic GN. CCL18 serum levels were higher in patients who suffered from ANCA-associated renal relapses compared with those in patients who remained in remission. Using a murine model of crescentic GN, we explored the effects of the CCL18 murine functional analog CCL8 and its receptor CCR8 on kidney function and morphology. Compared with wild-type mice, Ccr8(-/-) mice had significantly less infiltration of pathogenic mononuclear phagocytes. Furthermore, Ccr8(-/-) mice maintained renal function better and had reduced renal tissue injury. In summary, our data indicate that CCL18 drives renal inflammation through CCR8-expressing cells and could serve as a biomarker for disease activity and renal relapse in ANCA-associated crescentic GN.

  15. Chemokines and cytokines in patients with an occult Onchocerca volvulus infection.

    PubMed

    Lechner, Christian J; Gantin, Richard G; Seeger, Tanja; Sarnecka, Alicja; Portillo, Jennifer; Schulz-Key, Hartwig; Karabou, Potochoziou K; Helling-Giese, Gertrud; Heuschkel, Christoph; Banla, Meba; Soboslay, Peter T

    2012-05-01

    Repeated ivermectin treatment will clear microfilaria (Mf) of Onchocerca volvulus from skin and eyes of onchocerciasis patients while adult filaria remains alive and reproductive, and such occult O. volvulus infection may persist for years. To investigate the effect of residual adult filaria on the immune response profile, chemokines and cytokines were quantified 1) in onchocerciasis patients who developed an occult O. volvulus infection (Mf-negative) due to repeated ivermectin treatments, 2) patients who became Mf-negative without ivermectin treatments due to missing re-infection, and 3) endemic and non-endemic O. volvulus Mf-negative controls. With occult O. volvulus infection, serum levels of pro-inflammatory chemokines MCP-1/CCL2, MIP-1α/CCL3, MIP-1β/CCL4, MPIF-1/CCL23 and CXCL8/IL-8 enhanced and approached higher concentrations as determined in infection-free controls, whilst regulatory and Th2-type cytokines and chemokines MCP-4/CCL13, MIP-1δ/CCL15, TARC/CCL17 and IL-13 lessened. Levels of Eotaxin-2/CCL24, MCP-3/CCL7 and BCA-1/CXCL13 remained unchanged. At 3 days post-initial ivermectin treatment, MCP-1/CCL2, MCP-4/CCL13, MPIF-1/CCL23 and Eotaxin-2/CCL24 were strongly enhanced, suggesting that monocytes and eosinophil granulocytes have mediated Mf clearance. In summary, with occult and expiring O. volvulus infections the serum levels of inflammatory chemokines enhanced over time while regulatory and Th2-type-promoting cytokines and chemokines lessened; these changes may reflect a decreasing effector cell activation against Mf of O. volvulus, and in parallel, an enhancing inflammatory immune responsiveness. PMID:22202179

  16. Antithrombin Regulates Matriptase Activity Involved in Plasmin Generation, Syndecan Shedding, and HGF Activation in Keratinocytes

    PubMed Central

    Chen, Ya-Wen; Xu, Zhenghong; Baksh, Adrienne N. H.; Wang, Jehng-Kang; Chen, Chiu-Yuan; Swanson, Richard; Olson, Steve T.; Kataoka, Hiroaki; Johnson, Michael D.; Lin, Chen-Yong

    2013-01-01

    Matriptase, a membrane-associated serine protease, plays an essential role in epidermal barrier function through activation of the glycosylphosphatidylinositol (GPI)-anchored serine protease prostasin. The matriptase-prostasin proteolytic cascade is tightly regulated by hepatocyte growth factor activator inhibitor (HAI)-1 such that matriptase autoactivation and prostasin activation occur simultaneously and are followed immediately by the inhibition of both enzymes by HAI-1. However, the mechanisms whereby matriptase acts on extracellular substrates remain elusive. Here we report that some active matriptase can escape HAI-1 inhibition by being rapidly shed from the cell surface. In the pericellular environment, shed active matriptase is able to activate hepatocyte growth factor (HGF), accelerate plasminogen activation, and shed syndecan 1. The amount of active matriptase shed is inversely correlated with the amount of antithrombin (AT) bound to the surface of the keratinocytes. Binding of AT to the surface of keratinocytes is dependent on a functional heparin binding site, Lys-125, and that the N-glycosylation site Asn-135 be unglycosylated. This suggests that β-AT, and not α-AT, is responsible for regulation of pericellular matriptase activity in keratinocytes. Keratinocytes appear to rely on AT to regulate the level of pericellular active matriptase much more than breast and prostate epithelial cells in which AT regulation of matriptase activity occurs at much lower levels than keratinocytes. These results suggest that keratinocytes employ two distinct serine protease inhibitors to control the activation and processing of two different sets of matriptase substrates leading to different biological events: 1) HAI-1 for prostasin activation/inhibition, and 2) AT for the pericellular proteolysis involved in HGF activation, accelerating plasminogen activation, and shedding of syndecans. PMID:23675430

  17. Regulation of transcription and activity of Rhizobium etli glutaminase A.

    PubMed

    Huerta-Saquero, Alejandro; Calderón-Flores, Arturo; Díaz-Villaseñor, Andrea; Du Pont, Gisela; Durán, Socorro

    2004-08-01

    The present study determines the regulatory mechanisms that operate on Rhizobium etli glutaminase A. glsA gene expression levels were evaluated under several metabolic conditions by fusions of the glsA gene promoter and the transcriptional reporter cassette uidA2-aad. glsA expression was directly correlated to the glutaminase A activity found under the tested growth conditions, reaching its maximum level in the presence of glutamine and during exponential growth phase. Glutamine induces glsA expression. The influence of allosteric metabolites on glutaminase A activity was also determined. The purified enzyme was inhibited by 2-oxoglutarate and pyruvate, whereas oxaloacetate and glyoxylate modulate it positively. Glutaminase A is not inhibited by glutamate and is activated by ammonium. Glutaminase A participates in an ATP-consuming cycle where glutamine is continually degraded and resynthesized by glutamine synthetase (GS). GS and glutaminase A activities appear simultaneously during bacterial growth under different metabolic conditions and their control mechanisms are not reciprocal. Slight overproduction in glutaminase A expression causes a reduction in growth yield and a dramatic decrease in bacterial growth. We propose a model for regulation of glutaminase A, and discuss its contribution to glutamine cycle regulation. PMID:15279892

  18. Mycoplasma arthritidis mitogen up-regulates human NK cell activity.

    PubMed Central

    D'Orazio, J A; Cole, B C; Stein-Streilein, J

    1996-01-01

    While the effects of superantigens on T lymphocytes are well characterized, how superantigens interact with other immune cells is less clear. This report examines the effects of Mycoplasma arthritidis mitogen (MAM) on human natural killer (NK) cell activity. Incubation of peripheral blood mononuclear cells (PBMC) with MAM for 16 to 20 h augmented NK cytotoxicity (against K562) in a dose-dependent manner (P < or = 0.05). Superantigen-dependent cellular cytotoxicity, an activity of superantigen-activated cytotoxic T cells, was not involved in lysis of K562 cells because the erythroleukemic tumor target cells expressed no class II major histocompatibility complex by fluorescence-activated cell sorter analysis. Kinetic experiments showed that the largest increase in NK activity induced by MAM occurred within 48 h. Incubation with MAM caused a portion of NK cells to become adherent to tissue culture flasks, a quality associated with activation, and augmented NK activity was found in both adherent and nonadherent subpopulations. Experiments using cytokine-specific neutralizing antibodies showed that interleukin-2 contributed to enhancement of the NK activity observed in superantigen-stimulated PBMC. Interestingly, MAM was able to augment NK lysis of highly purified NK (CD56+) cells in the absence of other immune cells in 9 of 12 blood specimens, with the augmented lytic activity ranging from 110 to 170% of unstimulated NK activity. In summary, data presented in this report show for the first time that MAM affects human NK cells directly by increasing their lytic capacity and indirectly in PBMC as a consequence of cytokines produced by T cells. Results of this work suggest that, in vivo, one consequence of interaction with superantigen-secreting microorganisms may be up-regulation of NK lytic activity. These findings may have clinical application as a means of generating augmented NK effector cells useful in the immunotherapy of parasitic infections or neoplasms. PMID

  19. Human T cell leukaemia virus type 2 tax protein mediates CC-chemokine expression in peripheral blood mononuclear cells via the nuclear factor kappa B canonical pathway.

    PubMed

    Barrios, C S; Castillo, L; Zhi, H; Giam, C-Z; Beilke, M A

    2014-01-01

    Retroviral co-infections with human immunodeficiency virus type-1 (HIV-1) and human T cell leukaemia virus type 1 (HTLV-1) or type 2 (HTLV-2) are prevalent in many areas worldwide. It has been observed that HIV-1/HTLV-2 co-infections are associated with slower rates of CD4(+) T cell decline and delayed progression to AIDS. This immunological benefit has been linked to the ability of Tax2, the transcriptional activating protein of HTLV-2, to induce the expression of macrophage inflammatory protein (MIP)-1α/CCL3, MIP-1β/CCL4 and regulated upon activation normal T cell expressed and secreted (RANTES)/CCL5 and to down-regulate the expression of the CCR5 co-receptor in peripheral blood mononuclear cells (PBMCs). This study aimed to assess the role of Tax2-mediated activation of the nuclear factor kappa B (NF-κB) signalling pathway on the production of the anti-viral CC-chemokines MIP-1α, MIP-1β and RANTES. Recombinant Tax1 and Tax2 proteins, or proteins expressed via adenoviral vectors used to infect cells, were tested for their ability to activate the NF-κB pathway in cultured PBMCs in the presence or absence of NF-κB pathway inhibitors. Results showed a significant release of MIP-1α, MIP-1β and RANTES by PBMCs after the activation of p65/RelA and p50. The secretion of these CC-chemokines was significantly reduced (P < 0·05) by canonical NF-κB signalling inhibitors. In conclusion, Tax2 protein may promote innate anti-viral immune responses through the activation of the canonical NF-κB pathway.

  20. Calcium and cargoes as regulators of myosin 5a activity

    SciTech Connect

    Sellers, James R. Thirumurugan, Kavitha; Sakamoto, Takeshi; Hammer, John A.; Knight, Peter J.

    2008-04-25

    Myosin 5a is a two-headed actin-dependent motor that transports various cargoes in cells. Its enzymology and mechanochemistry have been extensively studied in vitro. It is a processive motor that takes multiple 36 nm steps on actin. The enzymatic activity of myosin 5 is regulated by an intramolecular folding mechanism whereby its lever arms fold back against the coiled-coil tail such that the motor domains directly bind the globular tail domains. We show that the structure seen in individual folded molecules is consistent with electron density map of two-dimensional crystals of the molecule. In this compact state, the actin-activated MgATPase activity of the molecule is markedly inhibited and the molecule cannot move processively on surface bound actin filaments. The actin-activated MgATPase activity of myosin 5a is activated by increasing the calcium concentration or by binding of a cargo-receptor molecule, melanophilin, in vitro. However, calcium binding to the calmodulin light chains results in dissociation of some of the calmodulin which disrupts the ability of myosin 5a to move on actin filaments in vitro. Thus we propose that the physiologically relevant activation pathway in vivo involves binding of cargo-receptor proteins.