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Park HK, Na YH, Nguyen HT, Nguyen LP, Hurh S, Seong JY, Lee CS, Ham BJ, Hwang JI. Analysis of CCR2 splice variant expression patterns and functional properties. Cell Biosci 2022; 12:59. [PMID: 35551672 PMCID: PMC9102224 DOI: 10.1186/s13578-022-00787-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2022] [Accepted: 04/12/2022] [Indexed: 11/25/2022] Open
Abstract
Background C–C motif chemokine receptor 2 (CCR2), the main receptor for monocyte chemoattractant protein-1 (MCP-1), is expressed on immune cells, including monocytes, macrophages, and activated T cells, and mediates cell migration toward MCP-1 in inflammation-related diseases. The CCR2 gene encodes two isoforms: CCR2A and CCR2B. The CCR2B open reading frame is localized in a single exon, similar to other chemokine receptors, and CCR2A and CCR2B feature different amino acid sequences in their C-terminal intracellular loops due to alternative splicing. Most biochemical studies on CCR2-related cellular responses in the immune system have focused on CCR2B, with few reports focused on CCR2A. Understanding the functional properties of CCR2A in cellular responses may elucidate the roles played by MCP-1 and CCR2 in pathophysiological responses. Results CCR2 gene expression analysis in several cell types revealed that most adherent cells only expressed CCR2A, whereas CCR2B expression was dominant in monocytic cells. The C-terminal Helix 8 region of CCR2A contains few basic amino acids, which may be unfavorable for cell surface localization, as confirmed with the HiBiT assay. CCR2B contains many C-terminal Ser/Thr residues, similar to other chemokine receptors, which may be phosphorylated by G protein–coupled receptor kinases (GRKs) to promote β-arrestin recruitment and subsequent endocytosis. By contrast, CCR2A contains few C-terminal Ser/Thr residues, which are unlikely to be phosphorylated by GRKs. CCR2A localized on the cell surface is resistant to internalization, despite the interaction between Gβ and GRKs induced by ligand binding with CCR2A. CCR2A induced cellular responses at a relatively higher degree than CCR2B, although both receptors mediated signaling events through Gαq and Gαi. HeLa cells lacking CCR2A showed slowed growth compared with parent cells, regardless of MCP-1 stimulation, and their chemotactic activity toward MCP-1, in addition to basal motility, was significantly impaired. Conclusion MCP-1 and CCR2 may play pivotal roles in cancer progression by recruiting macrophages into cancer tissue. This study demonstrates that CCR2A but not CCR2B is expressed in solid cancer–derived cells. CCR2A is resistant to internalization by β-arrestin due to a distinct C-terminal region from CCR2B, which enhances MCP-1-stimulated responses, indicating that CCR2A may play essential roles in solid cancer progression. Supplementary Information The online version contains supplementary material available at 10.1186/s13578-022-00787-6.
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Vincenzi M, Milella MS, D’Ottavio G, Caprioli D, Reverte I, Maftei D. Targeting Chemokines and Chemokine GPCRs to Enhance Strong Opioid Efficacy in Neuropathic Pain. Life (Basel) 2022; 12:life12030398. [PMID: 35330149 PMCID: PMC8955776 DOI: 10.3390/life12030398] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2022] [Revised: 03/06/2022] [Accepted: 03/07/2022] [Indexed: 12/21/2022] Open
Abstract
Neuropathic pain (NP) originates from an injury or disease of the somatosensory nervous system. This heterogeneous origin and the possible association with other pathologies make the management of NP a real challenge. To date, there are no satisfactory treatments for this type of chronic pain. Even strong opioids, the gold-standard analgesics for nociceptive and cancer pain, display low efficacy and the paradoxical ability to exacerbate pain sensitivity in NP patients. Mounting evidence suggests that chemokine upregulation may be a common mechanism driving NP pathophysiology and chronic opioid use-related consequences (analgesic tolerance and hyperalgesia). Here, we first review preclinical studies on the role of chemokines and chemokine receptors in the development and maintenance of NP. Second, we examine the change in chemokine expression following chronic opioid use and the crosstalk between chemokine and opioid receptors. Then, we examine the effects of inhibiting specific chemokines or chemokine receptors as a strategy to increase opioid efficacy in NP. We conclude that strong opioids, along with drugs that block specific chemokine/chemokine receptor axis, might be the right compromise for a favorable risk/benefit ratio in NP management.
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Affiliation(s)
- Martina Vincenzi
- Department of Physiology and Pharmacology “Vittorio Erspamer”, Sapienza University of Rome, 00185 Rome, Italy;
- Correspondence: (M.V.); (I.R.)
| | - Michele Stanislaw Milella
- Toxicology and Poison Control Center Unit, Department of Emergency, Anesthesia and Critical Care, Policlinico Umberto I Hospital-Sapienza University of Rome, 00161 Rome, Italy;
| | - Ginevra D’Ottavio
- Santa Lucia Foundation (IRCCS Fondazione Santa Lucia), 00143 Rome, Italy; (G.D.); (D.C.)
- Laboratory Affiliated to Institute Pasteur Italia-Fondazione Cenci Bolognetti, Department of Physiology and Pharmacology “Vittorio Erspamer”, Sapienza University of Rome, 00185 Rome, Italy
| | - Daniele Caprioli
- Santa Lucia Foundation (IRCCS Fondazione Santa Lucia), 00143 Rome, Italy; (G.D.); (D.C.)
- Laboratory Affiliated to Institute Pasteur Italia-Fondazione Cenci Bolognetti, Department of Physiology and Pharmacology “Vittorio Erspamer”, Sapienza University of Rome, 00185 Rome, Italy
| | - Ingrid Reverte
- Department of Physiology and Pharmacology “Vittorio Erspamer”, Sapienza University of Rome, 00185 Rome, Italy;
- Santa Lucia Foundation (IRCCS Fondazione Santa Lucia), 00143 Rome, Italy; (G.D.); (D.C.)
- Correspondence: (M.V.); (I.R.)
| | - Daniela Maftei
- Department of Physiology and Pharmacology “Vittorio Erspamer”, Sapienza University of Rome, 00185 Rome, Italy;
- Santa Lucia Foundation (IRCCS Fondazione Santa Lucia), 00143 Rome, Italy; (G.D.); (D.C.)
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3
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Abdi A, AlOtaiby S, Badarin FA, Khraibi A, Hamdan H, Nader M. Interaction of SARS-CoV-2 with cardiomyocytes: Insight into the underlying molecular mechanisms of cardiac injury and pharmacotherapy. Biomed Pharmacother 2022; 146:112518. [PMID: 34906770 PMCID: PMC8654598 DOI: 10.1016/j.biopha.2021.112518] [Citation(s) in RCA: 23] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2021] [Revised: 11/15/2021] [Accepted: 12/06/2021] [Indexed: 01/07/2023] Open
Abstract
SARS-CoV-2 causes respiratory illness with a spectrum of systemic complications. However, the mechanism for cardiac infection and cardiomyocyte injury in COVID-19 patients remains unclear. The current literature supports the notion that SARS-CoV-2 particles access the heart either by the circulating blood cells or by extracellular vesicles, originating from the inflamed lungs, and encapsulating the virus along with its receptor (ACE2). Both cardiomyocytes and pericytes (coronary arteries) express the necessary accessory proteins for access of SARS-CoV-2 particles (i.e. ACE2, NRP-1, TMPRSS2, CD147, integrin α5β1, and CTSB/L). These proteins facilitate the SARS-CoV-2 interaction and entry into the pericytes and cardiomyocytes thus leading to cardiac manifestations. Subsequently, various signaling pathways are altered in the infected cardiomyocytes (i.e. increased ROS production, reduced contraction, impaired calcium homeostasis), causing cardiac dysfunction. The currently adopted pharmacotherapy in severe COVID-19 subjects exhibited side effects on the heart, often manifested by electrical abnormalities. Nonetheless, cardiovascular adverse repercussions have been associated with the advent of some of the SARS-CoV-2 vaccines with no clear mechanisms underlining these complications. We provide herein an overview of the pathways involved with cardiomyocyte in COVID-19 subjects to help promoting pharmacotherapies that can protect against SARS-CoV-2-induced cardiac injuries.
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Affiliation(s)
- Abdulhamid Abdi
- Department of Physiology and Immunology, College of Medicine and Health Sciences, and Biotechnology Center, Khalifa University of Science and Technology, Abu Dhabi, United Arab Emirates
| | - Shahad AlOtaiby
- Research Center, King Fahad Medical City, Central Second Health Cluster, Ministry of Health, Riyadh, Saudi Arabia
| | - Firas Al Badarin
- Heart and Vascular Institute, Cleveland Clinic Abu Dhabi, Abu Dhabi, United Arab Emirates
| | - Ali Khraibi
- Department of Physiology and Immunology, College of Medicine and Health Sciences, and Biotechnology Center, Khalifa University of Science and Technology, Abu Dhabi, United Arab Emirates
| | - Hamdan Hamdan
- Department of Physiology and Immunology, College of Medicine and Health Sciences, and Biotechnology Center, Khalifa University of Science and Technology, Abu Dhabi, United Arab Emirates
| | - Moni Nader
- Department of Physiology and Immunology, College of Medicine and Health Sciences, and Biotechnology Center, Khalifa University of Science and Technology, Abu Dhabi, United Arab Emirates.
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4
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Nickoloff-Bybel EA, Festa L, Meucci O, Gaskill PJ. Co-receptor signaling in the pathogenesis of neuroHIV. Retrovirology 2021; 18:24. [PMID: 34429135 PMCID: PMC8385912 DOI: 10.1186/s12977-021-00569-x] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2021] [Accepted: 08/11/2021] [Indexed: 12/13/2022] Open
Abstract
The HIV co-receptors, CCR5 and CXCR4, are necessary for HIV entry into target cells, interacting with the HIV envelope protein, gp120, to initiate several signaling cascades thought to be important to the entry process. Co-receptor signaling may also promote the development of neuroHIV by contributing to both persistent neuroinflammation and indirect neurotoxicity. But despite the critical importance of CXCR4 and CCR5 signaling to HIV pathogenesis, there is only one therapeutic (the CCR5 inhibitor Maraviroc) that targets these receptors. Moreover, our understanding of co-receptor signaling in the specific context of neuroHIV is relatively poor. Research into co-receptor signaling has largely stalled in the past decade, possibly owing to the complexity of the signaling cascades and functions mediated by these receptors. Examining the many signaling pathways triggered by co-receptor activation has been challenging due to the lack of specific molecular tools targeting many of the proteins involved in these pathways and the wide array of model systems used across these experiments. Studies examining the impact of co-receptor signaling on HIV neuropathogenesis often show activation of multiple overlapping pathways by similar stimuli, leading to contradictory data on the effects of co-receptor activation. To address this, we will broadly review HIV infection and neuropathogenesis, examine different co-receptor mediated signaling pathways and functions, then discuss the HIV mediated signaling and the differences between activation induced by HIV and cognate ligands. We will assess the specific effects of co-receptor activation on neuropathogenesis, focusing on neuroinflammation. We will also explore how the use of substances of abuse, which are highly prevalent in people living with HIV, can exacerbate the neuropathogenic effects of co-receptor signaling. Finally, we will discuss the current state of therapeutics targeting co-receptors, highlighting challenges the field has faced and areas in which research into co-receptor signaling would yield the most therapeutic benefit in the context of HIV infection. This discussion will provide a comprehensive overview of what is known and what remains to be explored in regard to co-receptor signaling and HIV infection, and will emphasize the potential value of HIV co-receptors as a target for future therapeutic development. ![]()
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Affiliation(s)
- E A Nickoloff-Bybel
- Department of Pharmacology and Physiology, Drexel University College of Medicine, 245 N. 15th Street, Philadelphia, PA, 19102, USA
| | - L Festa
- Department of Basic and Translational Sciences, School of Dental Medicine, University of Pennsylvania, 240 S. 40th Street, Philadelphia, PA, 19104, USA
| | - O Meucci
- Department of Pharmacology and Physiology, Drexel University College of Medicine, 245 N. 15th Street, Philadelphia, PA, 19102, USA.,Department of Microbiology and Immunology, Drexel University College of Medicine, Philadelphia, PA, 19102, USA
| | - P J Gaskill
- Department of Pharmacology and Physiology, Drexel University College of Medicine, 245 N. 15th Street, Philadelphia, PA, 19102, USA.
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5
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Lee SWL, Seager RJ, Litvak F, Spill F, Sieow JL, Leong PH, Kumar D, Tan ASM, Wong SC, Adriani G, Zaman MH, Kamm ARD. Integrated in silico and 3D in vitro model of macrophage migration in response to physical and chemical factors in the tumor microenvironment. Integr Biol (Camb) 2021; 12:90-108. [PMID: 32248236 DOI: 10.1093/intbio/zyaa007] [Citation(s) in RCA: 31] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2019] [Revised: 01/30/2020] [Accepted: 03/10/2020] [Indexed: 12/18/2022]
Abstract
Macrophages are abundant in the tumor microenvironment (TME), serving as accomplices to cancer cells for their invasion. Studies have explored the biochemical mechanisms that drive pro-tumor macrophage functions; however the role of TME interstitial flow (IF) is often disregarded. Therefore, we developed a three-dimensional microfluidic-based model with tumor cells and macrophages to study how IF affects macrophage migration and its potential contribution to cancer invasion. The presence of either tumor cells or IF individually increased macrophage migration directedness and speed. Interestingly, there was no additive effect on macrophage migration directedness and speed under the simultaneous presence of tumor cells and IF. Further, we present an in silico model that couples chemokine-mediated signaling with mechanosensing networks to explain our in vitro observations. In our model design, we propose IL-8, CCL2, and β-integrin as key pathways that commonly regulate various Rho GTPases. In agreement, in vitro macrophage migration remained elevated when exposed to a saturating concentration of recombinant IL-8 or CCL2 or to the co-addition of a sub-saturating concentration of both cytokines. Moreover, antibody blockade against IL-8 and/or CCL2 inhibited migration that could be restored by IF, indicating cytokine-independent mechanisms of migration induction. Importantly, we demonstrate the utility of an integrated in silico and 3D in vitro approach to aid the design of tumor-associated macrophage-based immunotherapeutic strategies.
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Affiliation(s)
- Sharon Wei Ling Lee
- BioSystems and Micromechanics IRG, Singapore-MIT Alliance for Research and Technology, Singapore, 138602, Singapore.,Department of Microbiology and Immunology, Yong Loo Lin School of Medicine, National University of Singapore (NUS), Singapore, 117597, Singapore.,Singapore Immunology Network (SIgN), Agency for Science, Technology, and Research (A*STAR), Singapore
| | - R J Seager
- Department of Biomedical Engineering, Boston University, Boston, MA, 02215, USA
| | - Felix Litvak
- Department of Biomedical Engineering, Boston University, Boston, MA, 02215, USA
| | - Fabian Spill
- Department of Biomedical Engineering, Boston University, Boston, MA, 02215, USA.,Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA.,School of Mathematics, University of Birmingham, Birmingham, B15 2TT, UK
| | - Je Lin Sieow
- Singapore Immunology Network (SIgN), Agency for Science, Technology, and Research (A*STAR), Singapore
| | - Penny Hweixian Leong
- Singapore Immunology Network (SIgN), Agency for Science, Technology, and Research (A*STAR), Singapore
| | - Dillip Kumar
- Singapore Immunology Network (SIgN), Agency for Science, Technology, and Research (A*STAR), Singapore
| | - Alrina Shin Min Tan
- Singapore Immunology Network (SIgN), Agency for Science, Technology, and Research (A*STAR), Singapore
| | - Siew Cheng Wong
- Department of Microbiology and Immunology, Yong Loo Lin School of Medicine, National University of Singapore (NUS), Singapore, 117597, Singapore.,Singapore Immunology Network (SIgN), Agency for Science, Technology, and Research (A*STAR), Singapore
| | - Giulia Adriani
- Singapore Immunology Network (SIgN), Agency for Science, Technology, and Research (A*STAR), Singapore
| | - Muhammad Hamid Zaman
- Department of Biomedical Engineering, Boston University, Boston, MA, 02215, USA.,Howard Hughes Medical Institute, Boston University, Boston, MA, 02215, USA
| | - And Roger D Kamm
- Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA.,Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
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6
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van den Bos E, Ambrosy B, Horsthemke M, Walbaum S, Bachg AC, Wettschureck N, Innamorati G, Wilkie TM, Hanley PJ. Knockout mouse models reveal the contributions of G protein subunits to complement C5a receptor-mediated chemotaxis. J Biol Chem 2020; 295:7726-7742. [PMID: 32332099 DOI: 10.1074/jbc.ra119.011984] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2019] [Revised: 04/22/2020] [Indexed: 01/20/2023] Open
Abstract
G protein-coupled receptor signaling is required for the navigation of immune cells along chemoattractant gradients. However, chemoattractant receptors may couple to more than one type of heterotrimeric G protein, each of which consists of a Gα, Gβ, and Gγ subunit, making it difficult to delineate the critical signaling pathways. Here, we used knockout mouse models and time-lapse microscopy to elucidate Gα and Gβ subunits contributing to complement C5a receptor-mediated chemotaxis. Complement C5a-mediated chemokinesis and chemotaxis were almost completely abolished in macrophages lacking Gnai2 (encoding Gαi2), consistent with a reduced leukocyte recruitment previously observed in Gnai2 -/- mice, whereas cells lacking Gnai3 (Gαi3) exhibited only a slight decrease in cell velocity. Surprisingly, C5a-induced Ca2+ transients and lamellipodial membrane spreading were persistent in Gnai2 -/- macrophages. Macrophages lacking both Gnaq (Gαq) and Gna11 (Gα11) or both Gna12 (Gα12) and Gna13 (Gα13) had essentially normal chemotaxis, Ca2+ signaling, and cell spreading, except Gna12/Gna13-deficient macrophages had increased cell velocity and elongated trailing ends. Moreover, Gnaq/Gna11-deficient cells did not respond to purinergic receptor P2Y2 stimulation. Genetic deletion of Gna15 (Gα15) virtually abolished C5a-induced Ca2+ transients, but chemotaxis and cell spreading were preserved. Homozygous Gnb1 (Gβ1) deletion was lethal, but mice lacking Gnb2 (Gβ2) were viable. Gnb2 -/- macrophages exhibited robust Ca2+ transients and cell spreading, albeit decreased cell velocity and impaired chemotaxis. In summary, complement C5a-mediated chemotaxis requires Gαi2 and Gβ2, but not Ca2+ signaling, and membrane protrusive activity is promoted by G proteins that deplete phosphatidylinositol 4,5-bisphosphate.
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Affiliation(s)
- Esther van den Bos
- Institut für Molekulare Zellbiologie, Westfälische Wilhelms-Universität Münster, Münster, Germany
| | - Benjamin Ambrosy
- Institut für Molekulare Zellbiologie, Westfälische Wilhelms-Universität Münster, Münster, Germany
| | - Markus Horsthemke
- Institut für Molekulare Zellbiologie, Westfälische Wilhelms-Universität Münster, Münster, Germany
| | - Stefan Walbaum
- Institut für Molekulare Zellbiologie, Westfälische Wilhelms-Universität Münster, Münster, Germany
| | - Anne C Bachg
- Institut für Molekulare Zellbiologie, Westfälische Wilhelms-Universität Münster, Münster, Germany
| | - Nina Wettschureck
- Department of Pharmacology, Max Planck Institute for Heart and Lung Research, Bad Nauheim, Germany
| | - Giulio Innamorati
- Department of Surgical Sciences, Dentistry, Gynecology and Pediatrics, University of Verona, Verona, Italy
| | - Thomas M Wilkie
- Department of Pharmacology, University of Texas Southwestern Medical Center, Dallas, Texas, USA
| | - Peter J Hanley
- Institut für Molekulare Zellbiologie, Westfälische Wilhelms-Universität Münster, Münster, Germany
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7
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Nayak SU, Cicalese S, Tallarida C, Oliver CF, Rawls SM. Chemokine CCR5 and cocaine interactions in the brain: Cocaine enhances mesolimbic CCR5 mRNA levels and produces place preference and locomotor activation that are reduced by a CCR5 antagonist. Brain Behav Immun 2020; 83:288-292. [PMID: 31557508 PMCID: PMC6906231 DOI: 10.1016/j.bbi.2019.09.017] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/19/2019] [Revised: 09/06/2019] [Accepted: 09/21/2019] [Indexed: 01/22/2023] Open
Abstract
C-C chemokine receptor type 5, also known as CCR5 or CD195, is best known as a viral co-receptor that facilitates entry of HIV into cells. Evidence that CCR5 knockout mice display fewer dopamine neurons, lower striatal dopamine levels, and reduced locomotor activation compared to wild types also suggest a link between CCR5 receptors and cocaine dependence. Here, we tested the hypothesis using male Sprague-Dawley rats that cocaine-induced locomotor activation and conditioned place preference (CPP) are inhibited by a FDA-approved CCR5 antagonist (maraviroc), and that CCR5 gene expression in mesolimbic substrates is enhanced by repeated cocaine exposure. Pretreatment with maraviroc (1, 2.5, 5 mg/kg, IP) reduced hyperlocomotion induced by acute cocaine (10 mg/kg) without affecting spontaneous locomotor activity. For CPP experiments, rats conditioned with cocaine (10 mg/kg × 4 days, IP) were injected with maraviroc (1, 2.5, 5 mg/kg, IP) before each injection of cocaine. Maraviroc dose-dependently inhibited development of cocaine CPP, with a dose of 5 mg/kg producing a significant reduction. In rats treated repeatedly with cocaine (10 mg/kg × 4 days, IP), CCR5 gene expression was upregulated in the nucleus accumbens and ventral tegmental area but mRNA levels of CCR5 ligands (i.e., CCL3, CCL4 and CCL5) were not affected. Our results suggest that mesolimbic CCR5 receptors are dysregulated by cocaine exposure and, similar to CXCR4 and CCR2 receptors, influence behavioral effects related to the abuse liability of cocaine.
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Affiliation(s)
- Sunil U Nayak
- Center for Substance Abuse Research, Lewis Katz School of Medicine at Temple University, Philadelphia, PA, USA
| | - Stephanie Cicalese
- Center for Substance Abuse Research, Lewis Katz School of Medicine at Temple University, Philadelphia, PA, USA
| | - Chris Tallarida
- Center for Substance Abuse Research, Lewis Katz School of Medicine at Temple University, Philadelphia, PA, USA
| | - Chicora F. Oliver
- Department of Genetics, Emory University School of Medicine, Atlanta, GA, USA
| | - Scott M. Rawls
- Center for Substance Abuse Research, Lewis Katz School of Medicine at Temple University, Philadelphia, PA, USA,Department of Pharmacology, Lewis Katz School of Medicine at Temple University, Philadelphia, PA, USA
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8
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Gschwandtner M, Derler R, Midwood KS. More Than Just Attractive: How CCL2 Influences Myeloid Cell Behavior Beyond Chemotaxis. Front Immunol 2019; 10:2759. [PMID: 31921102 PMCID: PMC6923224 DOI: 10.3389/fimmu.2019.02759] [Citation(s) in RCA: 336] [Impact Index Per Article: 67.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2019] [Accepted: 11/11/2019] [Indexed: 12/15/2022] Open
Abstract
Monocyte chemoattractant protein-1 (MCP-1/CCL2) is renowned for its ability to drive the chemotaxis of myeloid and lymphoid cells. It orchestrates the migration of these cell types both during physiological immune defense and in pathological circumstances, such as autoimmune diseases including rheumatoid arthritis and multiple sclerosis, inflammatory diseases including atherosclerosis, as well as infectious diseases, obesity, diabetes, and various types of cancer. However, new data suggest that the scope of CCL2's functions may extend beyond its original characterization as a chemoattractant. Emerging evidence shows that it can impact leukocyte behavior, influencing adhesion, polarization, effector molecule secretion, autophagy, killing, and survival. The direction of these CCL2-induced responses is context dependent and, in some cases, synergistic with other inflammatory stimuli. The involvement of CCL2 signaling in multiple diseases renders it an interesting therapeutic target, although current targeting strategies have not met early expectations in the clinic. A better understanding of how CCL2 affects immune cells will be pivotal to the improvement of existing therapeutic approaches and the development of new drugs. Here, we provide an overview of the pleiotropic effects of CCL2 signaling on cells of the myeloid lineage, beyond chemotaxis, and highlight how these actions might help to shape immune cell behavior and tumor immunity.
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Affiliation(s)
- Martha Gschwandtner
- Kennedy Institute of Rheumatology, Nuffield Department of Orthopaedics, Rheumatology and Musculoskeletal Sciences, University of Oxford, Oxford, United Kingdom
| | - Rupert Derler
- Department of Pharmaceutical Chemistry, Institute of Pharmaceutical Sciences, University of Graz, Graz, Austria
| | - Kim S. Midwood
- Kennedy Institute of Rheumatology, Nuffield Department of Orthopaedics, Rheumatology and Musculoskeletal Sciences, University of Oxford, Oxford, United Kingdom
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9
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Selheim F, Aasebø E, Ribas C, Aragay AM. An Overview on G Protein-coupled Receptor-induced Signal Transduction in Acute Myeloid Leukemia. Curr Med Chem 2019; 26:5293-5316. [PMID: 31032748 DOI: 10.2174/0929867326666190429153247] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2018] [Revised: 03/22/2019] [Accepted: 04/05/2019] [Indexed: 02/06/2023]
Abstract
BACKGROUND Acute Myeloid Leukemia (AML) is a genetically heterogeneous disease characterized by uncontrolled proliferation of precursor myeloid-lineage cells in the bone marrow. AML is also characterized by patients with poor long-term survival outcomes due to relapse. Many efforts have been made to understand the biological heterogeneity of AML and the challenges to develop new therapies are therefore enormous. G Protein-coupled Receptors (GPCRs) are a large attractive drug-targeted family of transmembrane proteins, and aberrant GPCR expression and GPCR-mediated signaling have been implicated in leukemogenesis of AML. This review aims to identify the molecular players of GPCR signaling, focusing on the hematopoietic system, which are involved in AML to help developing novel drug targets and therapeutic strategies. METHODS We undertook an exhaustive and structured search of bibliographic databases for research focusing on GPCR, GPCR signaling and expression in AML. RESULTS AND CONCLUSION Many scientific reports were found with compelling evidence for the involvement of aberrant GPCR expression and perturbed GPCR-mediated signaling in the development of AML. The comprehensive analysis of GPCR in AML provides potential clinical biomarkers for prognostication, disease monitoring and therapeutic guidance. It will also help to provide marker panels for monitoring in AML. We conclude that GPCR-mediated signaling is contributing to leukemogenesis of AML, and postulate that mass spectrometrybased protein profiling of primary AML cells will accelerate the discovery of potential GPCR related biomarkers for AML.
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Affiliation(s)
- Frode Selheim
- The Proteomics Unit at the University of Bergen, Department of Biomedicine, University of Bergen, Jonas Lies vei 91, 5009 Bergen, Norway
| | - Elise Aasebø
- The Proteomics Unit at the University of Bergen, Department of Biomedicine, University of Bergen, Jonas Lies vei 91, 5009 Bergen, Norway.,Department of Clinical Science, University of Bergen, Jonas Lies vei 87, 5021 Bergen, Norway
| | - Catalina Ribas
- Departamento de Biología Molecular and Centro de Biología Molecular "Severo Ochoa" (UAM-CSIC), 28049 Madrid, Spain.,Instituto de Investigación Sanitaria La Princesa, 28006 Madrid, Spain.,CIBER de Enfermedades Cardiovasculares, ISCIII (CIBERCV), 28029 Madrid, Spain
| | - Anna M Aragay
- Departamento de Biologia Celular. Instituto de Biología Molecular de Barcelona (IBMB-CSIC), Spanish National Research Council (CSIC), Baldiri i Reixac, 15, 08028 Barcelona, Spain
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10
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Lorenzen E, Ceraudo E, Berchiche YA, Rico CA, Fürstenberg A, Sakmar TP, Huber T. G protein subtype-specific signaling bias in a series of CCR5 chemokine analogs. Sci Signal 2018; 11:11/552/eaao6152. [PMID: 30327411 DOI: 10.1126/scisignal.aao6152] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Chemokines and some chemical analogs of chemokines prevent cellular HIV-1 entry when bound to the HIV-1 coreceptors C-C chemokine receptor 5 (CCR5) or C-X-C chemokine receptor 4 (CXCR4), which are G protein-coupled receptors (GPCRs). The ideal HIV-1 entry blocker targeting the coreceptors would display ligand bias and avoid activating G protein-mediated pathways that lead to inflammation. We compared CCR5-dependent activation of second messenger pathways in a single cell line. We studied two endogenous chemokines [RANTES (also known as CCL5) and MIP-1α (also known as CCL3)] and four chemokine analogs of RANTES (5P12-, 5P14-, 6P4-, and PSC-RANTES). We found that CCR5 signaled through both Gi/o and Gq/11 IP1 accumulation and Ca2+ flux arose from Gq/11 activation, rather than from Gβγ subunit release after Gi/o activation as had been previously proposed. The 6P4- and PSC-RANTES analogs were superagonists for Gq/11 activation, whereas the 5P12- and 5P14-RANTES analogs displayed a signaling bias for Gi/o These results demonstrate that RANTES analogs elicit G protein subtype-specific signaling bias and can cause CCR5 to couple preferentially to Gq/11 rather than to Gi/o signaling pathways. We propose that G protein subtype-specific signaling bias may be a general feature of GPCRs that can couple to more than one G protein family.
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Affiliation(s)
- Emily Lorenzen
- Laboratory of Chemical Biology and Signal Transduction, The Rockefeller University, 1230 York Ave., New York, NY 10065, USA
| | - Emilie Ceraudo
- Laboratory of Chemical Biology and Signal Transduction, The Rockefeller University, 1230 York Ave., New York, NY 10065, USA
| | - Yamina A Berchiche
- Laboratory of Chemical Biology and Signal Transduction, The Rockefeller University, 1230 York Ave., New York, NY 10065, USA
| | - Carlos A Rico
- Laboratory of Chemical Biology and Signal Transduction, The Rockefeller University, 1230 York Ave., New York, NY 10065, USA
| | - Alexandre Fürstenberg
- Laboratory of Chemical Biology and Signal Transduction, The Rockefeller University, 1230 York Ave., New York, NY 10065, USA.,Department of Inorganic and Analytical Chemistry, University of Geneva, Quai Ernest-Ansermet 30, 1211 Geneva 4, Switzerland
| | - Thomas P Sakmar
- Laboratory of Chemical Biology and Signal Transduction, The Rockefeller University, 1230 York Ave., New York, NY 10065, USA. .,Department of Neurobiology, Care Sciences and Society, Division for Neurogeriatrics, Center for Alzheimer Research, Karolinska Institutet, 141 57 Huddinge, Sweden
| | - Thomas Huber
- Laboratory of Chemical Biology and Signal Transduction, The Rockefeller University, 1230 York Ave., New York, NY 10065, USA.
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11
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Arginine 313 of the putative 8th helix mediates Gα q/14 coupling of human CC chemokine receptors CCR2a and CCR2b. Cell Signal 2018; 53:170-183. [PMID: 30321592 DOI: 10.1016/j.cellsig.2018.10.007] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2018] [Revised: 10/08/2018] [Accepted: 10/10/2018] [Indexed: 01/29/2023]
Abstract
In man, two CC chemokine receptor isoforms, CCR2a and CCR2b, are present that belong to the rhodopsin-like G protein-coupled receptor family, and couple to Gi and Gq family members. The CCR2 receptors are known to regulate canonical functions of chemokines such as directed migration of leukocytes, and to potentially control non-canonical functions such as differentiation, proliferation, and gene transcription of immune and non-immune cells. We recently reported on the activation of phospholipase C isoenzymes and RhoA GTPases by coupling of the two CCR2 receptors to members of the Gq family, in particular Gαq and Gα14. So far little is known about the structural requirements for the CCR2/Gq/14 interaction. Interestingly, the CCR2 receptor isoforms are identical up to arginine 313 (R313) that is part of the putative 8th helix in CCR2 receptors, and the 8th helix has been implicated in the interaction of rhodopsin-like G protein-coupled receptors with Gαq. In the present work we describe that the 8th helix of both CCR2a and CCR2b is critically involved in selectively activating Gαq/14-regulated signaling. Refined analysis using various CCR2a and CCR2b mutants and analyzing their cellular signaling, e.g. ligand-dependent (i) activation of phospholipase C isoenzymes, (ii) stimulation of serum response factor-mediated gene transcription, (iii) activation of mitogen-activated protein kinases, (iv) internalization, and (v) changes in intracellular calcium concentrations, identified arginine 313 within the amino terminal portion of helix 8 to play a role for the agonist-mediated conformational changes and the formation of a Gαq/14 binding surface. We show that R313 determines Gαq/14 protein-dependent but not Gi protein-dependent cellular signaling, and plays no role in Gq/Gi-independent receptor internalization, indicating a role of R313 in biased signaling of CCR2 receptors.
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The role of catecholamines in HIV neuropathogenesis. Brain Res 2018; 1702:54-73. [PMID: 29705605 DOI: 10.1016/j.brainres.2018.04.030] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2018] [Revised: 04/21/2018] [Accepted: 04/24/2018] [Indexed: 12/21/2022]
Abstract
The success of anti-retroviral therapy has improved the quality of life and lifespan of HIV + individuals, transforming HIV infection into a chronic condition. These improvements have come with a cost, as chronic HIV infection and long-term therapy have resulted in the emergence of a number of new pathologies. This includes a variety of the neuropathological and neurocognitive effects collectively known as HIVassociated neurocognitive disorders (HAND) or NeuroHIV. These effects persist even in the absence of viral replication, suggesting that they are mediated the long-term changes in the CNS induced by HIV infection rather than by active replication. Among these effects are significant changes in catecholaminergic neurotransmission, especially in dopaminergic brain regions. In HIV-infected individuals not treated with ARV show prominent neuropathology is common in dopamine-rich brain regions and altered autonomic nervous system activity. Even infected individuals on therapy, there is significant dopaminergic neuropathology, and elevated stress and norepinephrine levels correlate with a decreased effectiveness of antiretroviral drugs. As catecholamines function as immunomodulatory factors, the resultant dysregulation of catecholaminergic tone could substantially alter the development of HIVassociated neuroinflammation and neuropathology. In this review, we discuss the role of catecholamines in the etiology of HIV neuropathogenesis. Providing a comprehensive examination of what is known about these molecules in the context of HIV-associated disease demonstrates the importance of further studies in this area, and may open the door to new therapeutic strategies that specifically ameliorate the effects of catecholaminergic dysregulation on NeuroHIV.
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Abstract
The human immunodeficiency virus (HIV) infects blood CD4 T cells through binding to CD4 and the chemokine co-receptor, CXCR4 or CCR5. This viral binding to CXCR4 or CCR5 also triggers the activation of a variety of signaling molecules such as LIMK/cofilin and WAVE2/Arp2/3 to promote actin dynamics, which are necessary for viral nuclear migration and the latent infection of blood resting CD4 T cells. In this chapter, we describe the methods for quantification of HIV-induced actin polymerization and cofilin phosphorylation in human T cells using flow cytometry.
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Nandi A, Bishayi B. CCR-2 neutralization augments murine fresh BMC activation by Staphylococcus aureus via two distinct mechanisms: at the level of ROS production and cytokine response. Innate Immun 2017; 23:345-372. [PMID: 28409543 DOI: 10.1177/1753425917697806] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
CCR-2 signaling regulates recruitment of monocytes from the bone marrow into the bloodstream and then to sites of infection. We sought to determine whether CCL-2/CCR-2 signaling is involved in the killing of Staphylococcus aureus by murine bone marrow cells (BMCs). The intermittent link of reactive oxygen species (ROS)-NF-κB/p38-MAPK-mediated CCL-2 production in CCR-2 signaling prompted us to determine whether neutralization of CCR-2 augments the response of murine fresh BMCs (FBMCs) after S. aureus infection. It was observed that anti-CCR-2 Ab-treated FBMCs released fewer ROS on encountering S. aureus infection than CCR-2 non-neutralized FBMCs, also correlating with reduced killing of S. aureus in CCR-2 neutralized FBMCs. Staphylococcal catalase and SOD were also found to play a role in protecting S. aureus from the ROS-mediated killing of FBMC. S. aureus infection of CCR-2 intact FBMCs pre-treated with either NF-κB or p-38-MAPK blocker induced less CCL-2, suggesting that NF-κB or p-38-MAPK is required for CCL-2 production by FBMCs. Moreover, blocking of CCR-2 along with NF-κB or p-38-MAPK resulted in elevated CCL-2 production and reduced CCR-2 expression. Inhibition of CCR-2 impairs the response of murine BMCs to S. aureus infection by attenuation ROS production and modulating the cytokine response.
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Affiliation(s)
- Ajeya Nandi
- Department of Physiology, Immunology Laboratory, University of Calcutta, University Colleges of Science and Technology, West Bengal, India
| | - Biswadev Bishayi
- Department of Physiology, Immunology Laboratory, University of Calcutta, University Colleges of Science and Technology, West Bengal, India
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15
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Novel role of cortactin in G protein-coupled receptor agonist-induced nuclear export and degradation of p21Cip1. Sci Rep 2016; 6:28687. [PMID: 27363897 PMCID: PMC4929470 DOI: 10.1038/srep28687] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2016] [Accepted: 06/08/2016] [Indexed: 12/16/2022] Open
Abstract
Monocyte chemotactic protein 1 (MCP1) stimulates phosphorylation of cortactin on Y421 and Y446 residues in a time-dependent manner and phosphorylation at Y446 but not Y421 residue is required for MCP1-induced CDK-interacting protein 1 (p21Cip1) nuclear export and degradation in facilitating human aortic smooth muscle cell (HASMC) proliferation. In addition, MCP1-induced cortactin tyrosine phosphorylation, p21Cip1 degradation and HASMC proliferation are dependent on Fyn activation. Upstream to Fyn, MCP1 stimulated C-C chemokine receptor type 2 (CCR2) and Gi/o and inhibition of either one of these molecules using their specific antagonists or inhibitors attenuated MCP1-induced cortactin tyrosine phosphorylation, p21Cip1 degradation and HASMC proliferation. Cortactin phosphorylation at Y446 residue is also required for another G protein-coupled receptor (GPCR) agonist, thrombin-induced p21Cip1 nuclear export and its degradation in promoting HASMC proliferation. Quite interestingly, the receptor tyrosine kinase (RTK) agonist, platelet-derived growth factor-BB (PDGF-BB)-induced p21Cip1 degradation and HASMC proliferation do not require cortactin tyrosine phosphorylation. Together, these findings demonstrate that tyrosine phosphorylation of cortactin at Y446 residue is selective for only GPCR but not RTK agonist-induced nuclear export and proteolytic degradation of p21Cip1 in HASMC proliferation.
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Auvynet C, Baudesson de Chanville C, Hermand P, Dorgham K, Piesse C, Pouchy C, Carlier L, Poupel L, Barthélémy S, Felouzis V, Lacombe C, Sagan S, Chemtob S, Quiniou C, Salomon B, Deterre P, Sennlaub F, Combadière C. ECL1i, d(LGTFLKC), a novel, small peptide that specifically inhibits CCL2-dependent migration. FASEB J 2016; 30:2370-81. [PMID: 26979087 DOI: 10.1096/fj.201500116] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2015] [Accepted: 02/25/2016] [Indexed: 11/11/2022]
Abstract
CC chemokine receptor type 2 (CCR2) is a key molecule in inflammatory diseases and is an obvious drug target for the treatment of inflammation. A number of nonpeptidic, competitive CCR2 antagonists have been developed, but none has yet been approved for clinical use. Our aim was to identify a short peptide that showed allosteric antagonism against human and mouse CCR2. On the basis of sequence analysis and 3-dimensional modeling, we identified an original 7-d-amino acid peptidic CCR2 inhibitor that we have called extracellular loop 1 inverso (ECL1i), d(LGTFLKC). In vitro, ECL1i selectively and potently inhibits CC chemokine ligand type 2 (CCL2)-triggered chemotaxis (IC50, 2 µM) but no other conventional CCL2-associated events. We used the classic competitive CCR2 antagonist, BMS22 {2-[(isopropylaminocarbonyl)amino]-N-[2-[[cis-2-[[4-(methylthio)benzoyl]amino]cyclohexyl]amino]-2-oxoethyl]-5-(trifluoromethyl)benzamide}, as positive control and inhibited CCL2-dependent chemotaxis with an IC50 of 18 nM. As negative control, we used a peptide with the same composition as ECL1i, but in a different sequence, d(FKLTLCG). In vivo, ECL1i (4 mg/kg) interfered with CCR2-positive cell recruitment and attenuated disease progression in experimental autoimmune encephalomyelitis, a mouse model of multiple sclerosis. This study establishes ECL1i as the first allosteric inhibitor of CCR2 with functional selectivity. ECL1i is a promising new agent in therapeutic development, and it may, by its selective effect, increase our understanding of CCR2 signaling pathways and functions.-Auvynet, C., Baudesson de Chanville, C., Hermand, P., Dorgham, K., Piesse, C., Pouchy, C., Carlier, L., Poupel, L., Barthélémy, S., Felouzis, V., Lacombe, C., Sagan, S., Salomon, B., Deterre, P., Sennlaub, F., Combadière, C. ECL1i, d(LGTFLKC), a novel, small peptide that specifically inhibits CCL2-dependent migration.
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Affiliation(s)
- Constance Auvynet
- *Sorbonne Universités, Université Pierre et Marie Curie (UPMC)/Univ Paris 06, Unité Mixte de Recherche Scientifique (UMRS) 1135, INSERM Unité 1135, Centre National de la Recherche Scientifique, Equipe de Recherche Labellisée (ERL) 8255, Centre d'Immunologie et des Maladies Infectieuses, Paris, France
| | - Camille Baudesson de Chanville
- *Sorbonne Universités, Université Pierre et Marie Curie (UPMC)/Univ Paris 06, Unité Mixte de Recherche Scientifique (UMRS) 1135, INSERM Unité 1135, Centre National de la Recherche Scientifique, Equipe de Recherche Labellisée (ERL) 8255, Centre d'Immunologie et des Maladies Infectieuses, Paris, France
| | - Patricia Hermand
- *Sorbonne Universités, Université Pierre et Marie Curie (UPMC)/Univ Paris 06, Unité Mixte de Recherche Scientifique (UMRS) 1135, INSERM Unité 1135, Centre National de la Recherche Scientifique, Equipe de Recherche Labellisée (ERL) 8255, Centre d'Immunologie et des Maladies Infectieuses, Paris, France
| | - Karim Dorgham
- *Sorbonne Universités, Université Pierre et Marie Curie (UPMC)/Univ Paris 06, Unité Mixte de Recherche Scientifique (UMRS) 1135, INSERM Unité 1135, Centre National de la Recherche Scientifique, Equipe de Recherche Labellisée (ERL) 8255, Centre d'Immunologie et des Maladies Infectieuses, Paris, France
| | - Christophe Piesse
- Sorbonne Universités, UPMC/Univ Paris 06, Institut de Biologie Paris-Seine (IBPS) 3631, CNRS, Service de Synthése Peptidique, Paris, France
| | - Charlotte Pouchy
- *Sorbonne Universités, Université Pierre et Marie Curie (UPMC)/Univ Paris 06, Unité Mixte de Recherche Scientifique (UMRS) 1135, INSERM Unité 1135, Centre National de la Recherche Scientifique, Equipe de Recherche Labellisée (ERL) 8255, Centre d'Immunologie et des Maladies Infectieuses, Paris, France
| | - Ludovic Carlier
- Sorbonne Universités, UPMC/Univ Paris 06, CNRS, UMR 7203, Laboratoire des Biomolécules, Paris, France
| | - Lucie Poupel
- *Sorbonne Universités, Université Pierre et Marie Curie (UPMC)/Univ Paris 06, Unité Mixte de Recherche Scientifique (UMRS) 1135, INSERM Unité 1135, Centre National de la Recherche Scientifique, Equipe de Recherche Labellisée (ERL) 8255, Centre d'Immunologie et des Maladies Infectieuses, Paris, France
| | - Sandrine Barthélémy
- *Sorbonne Universités, Université Pierre et Marie Curie (UPMC)/Univ Paris 06, Unité Mixte de Recherche Scientifique (UMRS) 1135, INSERM Unité 1135, Centre National de la Recherche Scientifique, Equipe de Recherche Labellisée (ERL) 8255, Centre d'Immunologie et des Maladies Infectieuses, Paris, France
| | - Virginie Felouzis
- *Sorbonne Universités, Université Pierre et Marie Curie (UPMC)/Univ Paris 06, Unité Mixte de Recherche Scientifique (UMRS) 1135, INSERM Unité 1135, Centre National de la Recherche Scientifique, Equipe de Recherche Labellisée (ERL) 8255, Centre d'Immunologie et des Maladies Infectieuses, Paris, France
| | - Claire Lacombe
- Sorbonne Universités, UPMC/Univ Paris 06, CNRS, UMR 7203, Laboratoire des Biomolécules, Paris, France; Ecole Normale Supérieure-Université de Recherche Paris Sciences et Lettres, Département de Chimie, Paris, France; Faculté des Sciences et Technologie, Université Paris Est Créteil-Val de Marne, Créteil, France
| | - Sandrine Sagan
- Sorbonne Universités, UPMC/Univ Paris 06, CNRS, UMR 7203, Laboratoire des Biomolécules, Paris, France
| | | | | | - Benoit Salomon
- *Sorbonne Universités, Université Pierre et Marie Curie (UPMC)/Univ Paris 06, Unité Mixte de Recherche Scientifique (UMRS) 1135, INSERM Unité 1135, Centre National de la Recherche Scientifique, Equipe de Recherche Labellisée (ERL) 8255, Centre d'Immunologie et des Maladies Infectieuses, Paris, France
| | - Philippe Deterre
- *Sorbonne Universités, Université Pierre et Marie Curie (UPMC)/Univ Paris 06, Unité Mixte de Recherche Scientifique (UMRS) 1135, INSERM Unité 1135, Centre National de la Recherche Scientifique, Equipe de Recherche Labellisée (ERL) 8255, Centre d'Immunologie et des Maladies Infectieuses, Paris, France
| | - Florian Sennlaub
- Sorbonne Universités, UPMC/ Univ Paris 06, UMRS 968, INSERM, U968, Institut de la Vision, Paris, France; Centre Hospitalier National d'Ophtalmologie des Quinze-Vingts, INSERM-Direction des Hôpitaux et de l'Offre de Soins (DHOS), Centre d'Investigation Clinique 503, Paris, France
| | - Christophe Combadière
- *Sorbonne Universités, Université Pierre et Marie Curie (UPMC)/Univ Paris 06, Unité Mixte de Recherche Scientifique (UMRS) 1135, INSERM Unité 1135, Centre National de la Recherche Scientifique, Equipe de Recherche Labellisée (ERL) 8255, Centre d'Immunologie et des Maladies Infectieuses, Paris, France;
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17
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Vatter P, Schuhholz J, Koenig C, Pfreimer M, Moepps B. Ligand-dependent serum response factor activation by the human CC chemokine receptors CCR2a and CCR2b is mediated by G proteins of the Gqfamily. J Leukoc Biol 2016; 99:979-91. [DOI: 10.1189/jlb.2ma0815-386r] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2015] [Accepted: 01/13/2016] [Indexed: 12/31/2022] Open
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Abstract
Heterotrimeric G proteins can be divided into Gi, Gs, Gq/11, and G12/13 subfamilies according to their α subunits. The main function of G proteins is transducing signals from G protein coupled receptors (GPCRs), a family of seven transmembrane receptors. In recent years, studies have demonstrated that GPCRs interact with Gq, a member of the Gq/11 subfamily of G proteins. This interaction facilitates the vital role of this family of proteins in immune regulation and autoimmunity, particularly for Gαq, which is considered the functional α subunit of Gq protein. Therefore, understanding the mechanisms through which Gq-coupled receptors control autoreactive lymphocytes is critical and may provide insights into the treatment of autoimmune disorders. In this review, we summarize recent advances in studies of the role of Gq-coupled receptors in autoimmunity, with a focus on their pathologic role and downstream signaling.
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19
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Janjanam J, Chandaka GK, Kotla S, Rao GN. PLCβ3 mediates cortactin interaction with WAVE2 in MCP1-induced actin polymerization and cell migration. Mol Biol Cell 2015; 26:4589-606. [PMID: 26490115 PMCID: PMC4678017 DOI: 10.1091/mbc.e15-08-0570] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2015] [Accepted: 10/13/2015] [Indexed: 12/24/2022] Open
Abstract
Monocyte chemotactic protein 1 (MCP1) stimulates vascular smooth muscle cell (VSMC) migration in vascular wall remodeling. However, the mechanisms underlying MCP1-induced VSMC migration have not been understood. Here we identify the signaling pathway associated with MCP1-induced human aortic smooth muscle cell (HASMC) migration. MCP1, a G protein-coupled receptor agonist, activates phosphorylation of cortactin on S405 and S418 residues in a time-dependent manner, and inhibition of its phosphorylation attenuates MCP1-induced HASMC G-actin polymerization, F-actin stress fiber formation, and migration. Cortactin phosphorylation on S405/S418 is found to be critical for its interaction with WAVE2, a member of the WASP family of cytoskeletal regulatory proteins required for cell migration. In addition, the MCP1-induced cortactin phosphorylation is dependent on PLCβ3-mediated PKCδ activation, and siRNA-mediated down-regulation of either of these molecules prevents cortactin interaction with WAVE2, affecting G-actin polymerization, F-actin stress fiber formation, and HASMC migration. Upstream, MCP1 activates CCR2 and Gαq/11 in a time-dependent manner, and down-regulation of their levels attenuates MCP1-induced PLCβ3 and PKCδ activation, cortactin phosphorylation, cortactin-WAVE2 interaction, G-actin polymerization, F-actin stress fiber formation, and HASMC migration. Together these findings demonstrate that phosphorylation of cortactin on S405 and S418 residues is required for its interaction with WAVE2 in MCP1-induced cytoskeleton remodeling, facilitating HASMC migration.
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Affiliation(s)
- Jagadeesh Janjanam
- Department of Physiology, University of Tennessee Health Science Center, Memphis, TN 38163
| | - Giri Kumar Chandaka
- Department of Physiology, University of Tennessee Health Science Center, Memphis, TN 38163
| | - Sivareddy Kotla
- Department of Physiology, University of Tennessee Health Science Center, Memphis, TN 38163
| | - Gadiparthi N Rao
- Department of Physiology, University of Tennessee Health Science Center, Memphis, TN 38163
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Singh SP, Foley JF, Zhang HH, Hurt DE, Richards JL, Smith CS, Liao F, Farber JM. Selectivity in the Use of Gi/o Proteins Is Determined by the DRF Motif in CXCR6 and Is Cell-Type Specific. Mol Pharmacol 2015; 88:894-910. [PMID: 26316539 DOI: 10.1124/mol.115.099960] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2015] [Accepted: 08/21/2015] [Indexed: 01/02/2023] Open
Abstract
CXCR6, the receptor for CXCL16, is expressed on multiple cell types and can be a coreceptor for human immunodeficiency virus 1. Except for CXCR6, all human chemokine receptors contain the D(3.49)R(3.50)Y(3.51) sequence, and all but two contain A(3.53) at the cytoplasmic terminus of the third transmembrane helix (H3C), a region within class A G protein-coupled receptors that contacts G proteins. In CXCR6, H3C contains D(3.49)R(3.50)F(3.51)I(3.52)V(3.53) at positions 126-130. We investigated the importance and interdependence of the canonical D126 and the noncanonical F128 and V130 in CXCR6 by mutating D126 to Y, F128 to Y, and V130 to A singly and in combination. For comparison, we mutated the analogous positions D142, Y144, and A146 to Y, F, and V, respectively, in CCR6, a related receptor containing the canonical sequences. Mutants were analyzed in both human embryonic kidney 293T and Jurkat E6-1 cells. Our data show that for CXCR6 and/or CCR6, mutations in H3C can affect both receptor signaling and chemokine binding; noncanonical H3C sequences are functionally linked, with dual changes mitigating the effects of single mutations; mutations in H3C that compromise receptor activity show selective defects in the use of individual Gi/o proteins; and the effects of mutations in H3C on receptor function and selectivity in Gi/o protein use can be cell-type specific. Our findings indicate that the ability of CXCR6 to make promiscuous use of the available Gi/o proteins is exquisitely dependent on sequences within the H3C and suggest that the native sequence allows for preservation of this function across different cellular environments.
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Affiliation(s)
- Satya P Singh
- Laboratory of Molecular Immunology (S.P.S., J.F.F., H.H.Z., J.L.R., C.S.S., F.L., J.M.F.) and Bioinformatics and Scientific IT Program, Office of Technology Information Systems, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland (D.E.H.); and Howard Hughes Medical Institute, National Institutes of Health Research Scholars Program, Bethesda, Maryland (C.S.S.)
| | - John F Foley
- Laboratory of Molecular Immunology (S.P.S., J.F.F., H.H.Z., J.L.R., C.S.S., F.L., J.M.F.) and Bioinformatics and Scientific IT Program, Office of Technology Information Systems, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland (D.E.H.); and Howard Hughes Medical Institute, National Institutes of Health Research Scholars Program, Bethesda, Maryland (C.S.S.)
| | - Hongwei H Zhang
- Laboratory of Molecular Immunology (S.P.S., J.F.F., H.H.Z., J.L.R., C.S.S., F.L., J.M.F.) and Bioinformatics and Scientific IT Program, Office of Technology Information Systems, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland (D.E.H.); and Howard Hughes Medical Institute, National Institutes of Health Research Scholars Program, Bethesda, Maryland (C.S.S.)
| | - Darrell E Hurt
- Laboratory of Molecular Immunology (S.P.S., J.F.F., H.H.Z., J.L.R., C.S.S., F.L., J.M.F.) and Bioinformatics and Scientific IT Program, Office of Technology Information Systems, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland (D.E.H.); and Howard Hughes Medical Institute, National Institutes of Health Research Scholars Program, Bethesda, Maryland (C.S.S.)
| | - Jennifer L Richards
- Laboratory of Molecular Immunology (S.P.S., J.F.F., H.H.Z., J.L.R., C.S.S., F.L., J.M.F.) and Bioinformatics and Scientific IT Program, Office of Technology Information Systems, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland (D.E.H.); and Howard Hughes Medical Institute, National Institutes of Health Research Scholars Program, Bethesda, Maryland (C.S.S.)
| | - Craig S Smith
- Laboratory of Molecular Immunology (S.P.S., J.F.F., H.H.Z., J.L.R., C.S.S., F.L., J.M.F.) and Bioinformatics and Scientific IT Program, Office of Technology Information Systems, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland (D.E.H.); and Howard Hughes Medical Institute, National Institutes of Health Research Scholars Program, Bethesda, Maryland (C.S.S.)
| | - Fang Liao
- Laboratory of Molecular Immunology (S.P.S., J.F.F., H.H.Z., J.L.R., C.S.S., F.L., J.M.F.) and Bioinformatics and Scientific IT Program, Office of Technology Information Systems, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland (D.E.H.); and Howard Hughes Medical Institute, National Institutes of Health Research Scholars Program, Bethesda, Maryland (C.S.S.)
| | - Joshua M Farber
- Laboratory of Molecular Immunology (S.P.S., J.F.F., H.H.Z., J.L.R., C.S.S., F.L., J.M.F.) and Bioinformatics and Scientific IT Program, Office of Technology Information Systems, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland (D.E.H.); and Howard Hughes Medical Institute, National Institutes of Health Research Scholars Program, Bethesda, Maryland (C.S.S.)
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Raman D, Sai J, Hawkins O, Richmond A. Adaptor protein2 (AP2) orchestrates CXCR2-mediated cell migration. Traffic 2014; 15:451-69. [PMID: 24450359 DOI: 10.1111/tra.12154] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2013] [Revised: 01/16/2014] [Accepted: 01/22/2014] [Indexed: 12/14/2022]
Abstract
The chemokine receptor CXCR2 is vital for inflammation, wound healing, angiogenesis, cancer progression and metastasis. Adaptor protein 2 (AP2), a clathrin binding heterotetrameric protein comprised of α, β2, μ2 and σ2 subunits, facilitates clathrin-mediated endocytosis. Mutation of the LLKIL motif in the CXCR2 carboxyl-terminal domain (CTD) results in loss of AP2 binding to the receptor and loss of ligand-mediated receptor internalization and chemotaxis. AP2 knockdown also results in diminished ligand-mediated CXCR2 internalization, polarization and chemotaxis. Using knockdown/rescue approaches with AP2-μ2 mutants, the binding domains were characterized in reference to CXCR2 internalization and chemotaxis. When in an open conformation, μ2 Patch 1 and Patch 2 domains bind tightly to membrane PIP2 phospholipids. When AP2-μ2, is replaced with μ2 mutated in Patch 1 and/or Patch 2 domains, ligand-mediated receptor binding and internalization are not lost. However, chemotaxis requires AP2-μ2 Patch 1, but not Patch 2. AP2-σ2 has been demonstrated to bind dileucine motifs to facilitate internalization. Expression of AP2-σ2 V88D and V98S dominant negative mutants resulted in loss of CXCR2 mediated chemotaxis. Thus, AP2 binding to both membrane phosphatidylinositol phospholipids and dileucine motifs is crucial for directional migration or chemotaxis. Moreover, AP2-mediated receptor internalization can be dissociated from AP2-mediated chemotaxis.
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Affiliation(s)
- Dayanidhi Raman
- Department of Veterans Affairs, Tennessee Valley Healthcare System, Nashville, TN, 37212, USA; Department of Cancer Biology, Vanderbilt University School of Medicine, Nashville, TN, 37232, USA
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Gaskill PJ, Yano HH, Kalpana GV, Javitch JA, Berman JW. Dopamine receptor activation increases HIV entry into primary human macrophages. PLoS One 2014; 9:e108232. [PMID: 25268786 PMCID: PMC4182469 DOI: 10.1371/journal.pone.0108232] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2014] [Accepted: 08/25/2014] [Indexed: 01/11/2023] Open
Abstract
Macrophages are the primary cell type infected with HIV in the central nervous system, and infection of these cells is a major component in the development of neuropathogenesis and HIV-associated neurocognitive disorders. Within the brains of drug abusers, macrophages are exposed to increased levels of dopamine, a neurotransmitter that mediates the addictive and reinforcing effects of drugs of abuse such as cocaine and methamphetamine. In this study we examined the effects of dopamine on HIV entry into primary human macrophages. Exposure to dopamine during infection increased the entry of R5 tropic HIV into macrophages, irrespective of the concentration of the viral inoculum. The entry pathway affected was CCR5 dependent, as antagonizing CCR5 with the small molecule inhibitor TAK779 completely blocked entry. The effect was dose-dependent and had a steep threshold, only occurring above 108 M dopamine. The dopamine-mediated increase in entry required dopamine receptor activation, as it was abrogated by the pan-dopamine receptor antagonist flupenthixol, and could be mediated through both subtypes of dopamine receptors. These findings indicate that the effects of dopamine on macrophages may have a significant impact on HIV pathogenesis. They also suggest that drug-induced increases in CNS dopamine may be a common mechanism by which drugs of abuse with distinct modes of action exacerbate neuroinflammation and contribute to HIV-associated neurocognitive disorders in infected drug abusers.
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Affiliation(s)
- Peter J. Gaskill
- Department of Pathology, Albert Einstein College of Medicine, Bronx, New York, United States of America
- * E-mail:
| | - Hideaki H. Yano
- Department of Psychiatry and Pharmacology, Columbia University, New York, New York, United States of America
| | - Ganjam V. Kalpana
- Department of Genetics, Albert Einstein College of Medicine, Bronx, New York, United States of America
- Department of Microbiology & Immunology, Albert Einstein College of Medicine, Bronx, New York, United States of America
| | - Jonathan A. Javitch
- Department of Psychiatry and Pharmacology, Columbia University, New York, New York, United States of America
| | - Joan W. Berman
- Department of Pathology, Albert Einstein College of Medicine, Bronx, New York, United States of America
- Department of Microbiology & Immunology, Albert Einstein College of Medicine, Bronx, New York, United States of America
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Hu X, Liou AKF, Leak RK, Xu M, An C, Suenaga J, Shi Y, Gao Y, Zheng P, Chen J. Neurobiology of microglial action in CNS injuries: receptor-mediated signaling mechanisms and functional roles. Prog Neurobiol 2014; 119-120:60-84. [PMID: 24923657 PMCID: PMC4121732 DOI: 10.1016/j.pneurobio.2014.06.002] [Citation(s) in RCA: 99] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2014] [Revised: 05/31/2014] [Accepted: 06/03/2014] [Indexed: 12/28/2022]
Abstract
Microglia are the first line of immune defense against central nervous system (CNS) injuries and disorders. These highly plastic cells play dualistic roles in neuronal injury and recovery and are known for their ability to assume diverse phenotypes. A broad range of surface receptors are expressed on microglia and mediate microglial 'On' or 'Off' responses to signals from other host cells as well as invading microorganisms. The integrated actions of these receptors result in tightly regulated biological functions, including cell mobility, phagocytosis, the induction of acquired immunity, and trophic factor/inflammatory mediator release. Over the last few years, significant advances have been made toward deciphering the signaling mechanisms related to these receptors and their specific cellular functions. In this review, we describe the current state of knowledge of the surface receptors involved in microglial activation, with an emphasis on their engagement of distinct functional programs and their roles in CNS injuries. It will become evident from this review that microglial homeostasis is carefully maintained by multiple counterbalanced strategies, including, but not limited to, 'On' and 'Off' receptor signaling. Specific regulation of theses microglial receptors may be a promising therapeutic strategy against CNS injuries.
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Affiliation(s)
- Xiaoming Hu
- Center of Cerebrovascular Disease Research, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213, USA; State Key Laboratory of Medical Neurobiology and Institute of Brain Sciences, Fudan University, Shanghai, China; Geriatric Research, Educational and Clinical Center, Veterans Affairs Pittsburgh Health Care System, Pittsburgh, PA 15240, USA.
| | - Anthony K F Liou
- Center of Cerebrovascular Disease Research, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213, USA
| | - Rehana K Leak
- Division of Pharmaceutical Sciences, Duquesne University, Pittsburgh, PA 15282, USA
| | - Mingyue Xu
- State Key Laboratory of Medical Neurobiology and Institute of Brain Sciences, Fudan University, Shanghai, China
| | - Chengrui An
- State Key Laboratory of Medical Neurobiology and Institute of Brain Sciences, Fudan University, Shanghai, China
| | - Jun Suenaga
- Center of Cerebrovascular Disease Research, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213, USA
| | - Yejie Shi
- Center of Cerebrovascular Disease Research, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213, USA
| | - Yanqin Gao
- State Key Laboratory of Medical Neurobiology and Institute of Brain Sciences, Fudan University, Shanghai, China
| | - Ping Zheng
- State Key Laboratory of Medical Neurobiology and Institute of Brain Sciences, Fudan University, Shanghai, China
| | - Jun Chen
- Center of Cerebrovascular Disease Research, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213, USA; State Key Laboratory of Medical Neurobiology and Institute of Brain Sciences, Fudan University, Shanghai, China; Geriatric Research, Educational and Clinical Center, Veterans Affairs Pittsburgh Health Care System, Pittsburgh, PA 15240, USA.
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CXCL12-Mediated Murine Neural Progenitor Cell Movement Requires PI3Kβ Activation. Mol Neurobiol 2013; 48:217-31. [DOI: 10.1007/s12035-013-8451-5] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2012] [Accepted: 03/25/2013] [Indexed: 11/26/2022]
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Patel J, Channon KM, McNeill E. The downstream regulation of chemokine receptor signalling: implications for atherosclerosis. Mediators Inflamm 2013; 2013:459520. [PMID: 23690662 PMCID: PMC3649756 DOI: 10.1155/2013/459520] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2012] [Accepted: 03/12/2013] [Indexed: 12/13/2022] Open
Abstract
Heterotrimeric G-protein-coupled receptors (GPCRs) are key mediators of intracellular signalling, control numerous physiological processes, and are one of the largest class of proteins to be pharmacologically targeted. Chemokine-induced macrophage recruitment into the vascular wall is an early pathological event in the progression of atherosclerosis. Leukocyte activation and chemotaxis during cell recruitment are mediated by chemokine ligation of multiple GPCRs. Regulation of GPCR signalling is critical in limiting vascular inflammation and involves interaction with downstream proteins such as GPCR kinases (GRKs), arrestin proteins and regulator of G-protein signalling (RGS) proteins. These have emerged as new mediators of atherogenesis by functioning in internalisation, desensitisation, and signal termination of chemokine receptors. Targeting chemokine signalling through these proteins may provide new strategies to alter atherosclerotic plaque formation and plaque biology.
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Affiliation(s)
- Jyoti Patel
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, John Radcliffe Hospital, Oxford OX3 9DU, UK
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford OX3 7BN, UK
| | - Keith M. Channon
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, John Radcliffe Hospital, Oxford OX3 9DU, UK
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford OX3 7BN, UK
| | - Eileen McNeill
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, John Radcliffe Hospital, Oxford OX3 9DU, UK
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford OX3 7BN, UK
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Otten JJT, de Jager SCA, Kavelaars A, Seijkens T, Bot I, Wijnands E, Beckers L, Westra MM, Bot M, Busch M, Bermudez B, van Berkel TJC, Heijnen CJ, Biessen EAL. Hematopoietic G-protein-coupled receptor kinase 2 deficiency decreases atherosclerotic lesion formation in LDL receptor-knockout mice. FASEB J 2012; 27:265-76. [PMID: 23047899 DOI: 10.1096/fj.12-205351] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Leukocyte chemotaxis is deemed instrumental in initiation and progression of atherosclerosis. It is mediated by G-protein-coupled receptors (e.g., CCR2 and CCR5), the activity of which is controlled by G-protein-coupled receptor kinases (GRKs). In this study, we analyzed the effect of hematopoietic deficiency of a potent regulator kinase of chemotaxis (GRK2) on atherogenesis. LDL receptor-deficient (LDLr(-/-)) mice with heterozygous hematopoietic GRK2 deficiency, generated by bone marrow transplantation (n=15), displayed a dramatic attenuation of plaque development, with 79% reduction in necrotic core and increased macrophage content. Circulating monocytes decreased and granulocytes increased in GRK2(+/-) chimeras, which could be attributed to diminished granulocyte colony-forming units in bone marrow. Collectively, these data pointed to myeloid cells as major mediators of the impaired atherogenic response in GRK2(+/-) chimeras. LDLr(-/-) mice with macrophage/granulocyte-specific GRK2 deficiency (LysM-Cre GRK2(flox/flox); n=8) failed to mimic the aforementioned phenotype, acquitting these cells as major responsible subsets for GRK2 deficiency-associated atheroprotection. To conclude, even partial hematopoietic GRK2 deficiency prevents atherosclerotic lesion progression beyond the fatty streak stage, identifying hematopoietic GRK2 as a potential target for intervention in atherosclerosis.
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Affiliation(s)
- Jeroen J T Otten
- Experimental Vascular Pathology Group, Department of Pathology, Cardiovascular Research Institute Maastricht, Maastricht University Medical Center, Maastricht, The Netherlands
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Mesenchymal stem cells secrete multiple cytokines that promote angiogenesis and have contrasting effects on chemotaxis and apoptosis. PLoS One 2012; 7:e35685. [PMID: 22558198 PMCID: PMC3338452 DOI: 10.1371/journal.pone.0035685] [Citation(s) in RCA: 240] [Impact Index Per Article: 20.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2011] [Accepted: 03/22/2012] [Indexed: 12/13/2022] Open
Abstract
We have previously shown that mesenchymal stem cells (MSC) improve function upon integration in ischemic myocardium. We examined whether specific cytokines and growth factors produced by MSCs are able to affect angiogenesis, cellular migration and apoptosis. Conditioned media (CM) was prepared by culturing MSC for 48 hours. CM displayed significantly elevated levels of VEGF, Monocyte Chemoattractant Protein-1 (MCP-1), macrophage inflammatory protein-1α (MIP-1α), MIP-1β and monokine induced by IFN-γ (MIG) compared to control media. MSC contained RNA for these factors as detected by RT-PCR. CM was able to induce angiogenesis in canine vascular endothelial cells. MCP-1 and MIP-1α increased cell migration of MSC while VEGF reduced it. H9c2 cells treated with CM under hypoxic conditions for 24 hours displayed a 16% reduction in caspase-3 activity compared to controls. PI 3-kinase γ inhibitor had no effect on controls but reversed the effect of CM on caspase-3 activity. MCP-1 alone mimicked the protective effect of CM while the PI 3-Kγ inhibitor did not reverse the effect of MCP-1. CM reduced phospho-BAD (Ser112) and phospho-Akt (Ser473) while increasing phospho-Akt (Thr308). MCP-1 reduced the level of phospho-Akt (Ser473) while having no effect on the other two; the PI 3-Kγ inhibitor did not alter the MCP-1 effect. ERK 1/2 phosphorylation was reduced in CM treated H9c2 cells, and inhibition of ERK 1/2 reduced the phosphorylation of Akt (Ser473), Akt (Thr308) and Bad (Ser112). In conclusion, MSC synthesize and secrete multiple paracrine factors that are able to affect MSC migration, promote angiogenesis and reduce apoptosis. While both MCP-1 and PI3-kinase are involved in the protective effect, they are independent of each other. It is likely that multiple pro-survival factors in addition to MCP-1 are secreted by MSC which act on divergent intracellular signaling pathways.
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Abstract
INTRODUCTION During embryogenesis, CXCR4, a chemokine receptor, and its ligand, stromal cell-derived factor-1 (SDF-1/CXCL12), are critically involved in the development of the hematopoietic, nerve and endothelial tissues by regulating tissue progenitor cell migration, homing and survival. In adult life, the CXCR4 axis serves as the key factor for stem and immune cell trafficking. More importantly, CXCR4-CXCL12 axis plays a critical role in HIV, stem cell mobilization, autoimmune diseases, cancer and tissue regeneration. Targeting the CXCR4-CXCL12 axis, therefore, is an attractive therapeutic approach in various diseases. AREAS COVERED In this review, we update current knowledge about CXCR4-CXCL12 biology, therapeutic approaches and therapeutic agents. The data presented was collected from http://www.ncbi.nlm.nih.gov/pubmed , http://clinicaltrials.gov/ , http://bloodjournal.hematologylibrary.org/ . EXPERT OPINION Development of CXCR4 antagonists with increased affinity, extended pharmacokinetics and/or pharmacodynamics and with the capacity to differentially target CXCR4 may lead to a development of novel therapeutics for HIV, cancer, tissue regeneration and stem cell collection.
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Affiliation(s)
- Amnon Peled
- Hadassah Hebrew University Hospital , Goldyne Savad Institute of Gene Therapy, Jerusalem, Israel.
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Serrano A, Paré M, McIntosh F, Elmes SJR, Martino G, Jomphe C, Lessard E, Lembo PMC, Vaillancourt F, Perkins MN, Cao CQ. Blocking spinal CCR2 with AZ889 reversed hyperalgesia in a model of neuropathic pain. Mol Pain 2010; 6:90. [PMID: 21143971 PMCID: PMC3009975 DOI: 10.1186/1744-8069-6-90] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2010] [Accepted: 12/10/2010] [Indexed: 11/26/2022] Open
Abstract
Background The CCR2/CCL2 system has been identified as a regulator in the pathogenesis of neuropathy-induced pain. However, CCR2 target validation in analgesia and the mechanism underlying antinociception produced by CCR2 antagonists remains poorly understood. In this study, in vitro and in vivo pharmacological approaches using a novel CCR2 antagonist, AZ889, strengthened the hypothesis of a CCR2 contribution to neuropathic pain and provided confidence over the possibilities to treat neuropathic pain with CCR2 antagonists. Results We provided evidence that dorsal root ganglia (DRG) cells harvested from CCI animals responded to stimulation by CCL2 with a concentration-dependent calcium rise involving PLC-dependent internal stores. This response was associated with an increase in evoked neuronal action potentials suggesting these cells were sensitive to CCR2 signalling. Importantly, treatment with AZ889 abolished CCL2-evoked excitation confirming that this activity is CCR2-mediated. Neuronal and non-neuronal cells in the spinal cord were also excited by CCL2 applications indicating an important role of spinal CCR2 in neuropathic pain. We next showed that in vivo spinal intrathecal injection of AZ889 produced dose-dependent analgesia in CCI rats. Additionally, application of AZ889 to the exposed spinal cord inhibited evoked neuronal activity and confirmed that CCR2-mediated analgesia involved predominantly the spinal cord. Furthermore, AZ889 abolished NMDA-dependent wind-up of spinal withdrawal reflex pathway in neuropathic animals giving insight into the spinal mechanism underlying the analgesic properties of AZ889. Conclusions Overall, this study strengthens the important role of CCR2 in neuropathic pain and highlights feasibility that interfering on this mechanism at the spinal level with a selective antagonist can provide new analgesia opportunities.
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Affiliation(s)
- Alexandre Serrano
- AstraZeneca R&D Montréal, 7171 Frédérick Banting, Ville St-Laurent (Montréal) Québec, Canada, H4S 1Z9
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Yang Y, Wu J, Lu Y. Mechanism of HIV-1-TAT induction of interleukin-1beta from human monocytes: Involvement of the phospholipase C/protein kinase C signaling cascade. J Med Virol 2010; 82:735-46. [PMID: 20336759 DOI: 10.1002/jmv.21720] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Human immunodeficiency virus TAT plays an important role in the disregulation of cytokine production associated with the neurological disorders that follow HIV infection. IL-1beta is one of the important inflammatory cytokines secreted by immune-activated monocytes/macrophages. Previous reports have shown that extracellular TAT stimulates IL-1beta expression in monocytes/macrophages. However, little is known about the mechanisms and possible TAT-responsive elements within the IL-1beta promoter. The present study shows that TAT increases the production of IL-1beta in human monocytes; PLC-PKC pathway-dependent phosphorylation of p44/42 and JNK MAP kinases participates partially in IL-1beta induction by TAT; specific C/EBP and NF-kappaB transcription factor binding elements within the IL-1beta promoter are involved in TAT regulation of IL-1beta production. This study identifies a signaling mechanism for HIV-1-induced IL-1beta production in human monocytes that may be involved in the neuropathogenesis of HIV-associated dementia.
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Affiliation(s)
- Yongbo Yang
- State Key Laboratory of Virology, College of Life Sciences, Wuhan University, Wuhan, China
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Lee MMK, Wong YH. CCR1-mediated activation of nuclear factor-κB in THP-1 monocytic cells involvespertussistoxin-insensitive Gα14and Gα16signaling cascades. J Leukoc Biol 2009; 86:1319-29. [DOI: 10.1189/jlb.0209052] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
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Rubin JB. Chemokine signaling in cancer: one hump or two? Semin Cancer Biol 2009; 19:116-22. [PMID: 18992347 PMCID: PMC2694237 DOI: 10.1016/j.semcancer.2008.10.001] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2008] [Revised: 10/08/2008] [Accepted: 10/10/2008] [Indexed: 10/21/2022]
Abstract
Chemokines and their receptors play essential roles in the development and function of multiple tissues. Chemokine expression, particularly CXCL12 and its receptor CXCR4, has prognostic significance in several cancers apparently due to chemokine mediated growth and metastatic spread. These observations provide the rationale for pursuing CXCR4 inhibition for cancer chemotherapy. However, the multiple homeostatic functions of CXCR4 may preclude global inhibition as a therapeutic strategy. Here I review CXCR4 signaling and how it might differ in normal and transformed cells with special emphasis on the role that altered CXCR4 counter-regulation might play in tumor biology. I propose that CXCR4 mediates unique signals in cancer cells as a consequence of abnormal counter-regulation and that this results in novel biological responses. The importance of testing this hypothesis lies in the possibility that targeting abnormal CXCR4 signaling might provide an anti-tumor effect without disturbing normal CXCR4 functions.
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Affiliation(s)
- Joshua B Rubin
- Department of Pediatrics/Division of Pediatric Hematology and Oncology, Campus Box 8208, 660 South Euclid Avenue, Washington University School of Medicine, St Louis, MO 63110, USA. rubin
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Alon R. Chapter 6 Membrane–Cytoskeletal Platforms for Rapid Chemokine Signaling to Integrins. CURRENT TOPICS IN MEMBRANES 2009. [DOI: 10.1016/s1063-5823(09)64006-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Harmon B, Ratner L. Induction of the Galpha(q) signaling cascade by the human immunodeficiency virus envelope is required for virus entry. J Virol 2008; 82:9191-205. [PMID: 18632858 PMCID: PMC2546909 DOI: 10.1128/jvi.00424-08] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2008] [Accepted: 07/08/2008] [Indexed: 12/13/2022] Open
Abstract
Binding of human immunodeficiency virus type 1 (HIV-1) envelope glycoprotein (Env) with the primary receptor CD4 and one of two coreceptors, CXCR4 or CCR5, activates a signaling cascade resulting in Rac-1 GTPase activation and stimulation of actin cytoskeletal reorganizations critical for HIV-1-mediated membrane fusion. The mechanism by which HIV-1 Env induces Rac-1 activation and subsequent actin cytoskeleton rearrangement is unknown. In this study, we show that Env-mediated Rac-1 activation is dependent on the activation of Galpha(q) and its downstream targets. Fusion and Rac-1 activation are mediated by Galpha(q) and phospholipase C (PLC), as shown by attenuation of fusion and Rac-1 activation in cells either expressing small interfering RNA (siRNA) targeting Galpha(q) or treated with the PLC inhibitor U73122. Rac-1 activation and fusion were also blocked by multiple protein kinase C inhibitors, by inhibitors of intracellular Ca2+ release, by Pyk2-targeted siRNA, and by the Ras inhibitor S-trans,trans-farnesylthiosalicylic acid (FTS). Fusion was blocked without altering cell viability or cell surface localization of CD4 and CCR5. Similar results were obtained when cell fusion was induced by Env expressed on viral and cellular membranes and when cell lines or primary cells were the target. Treatment with inhibitors and siRNA specific for Galpha(i) or Galpha(s) signaling mediators had no effect on Env-mediated Rac-1 activation or cell fusion, indicating that the Galpha(q) pathway alone is responsible. These results could provide a new focus for therapeutic intervention with drugs targeting host signaling mediators rather than viral molecules, a strategy which is less likely to result in resistance.
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Affiliation(s)
- Brooke Harmon
- Division of Molecular Oncology, Washington University School of Medicine, St. Louis, Missouri, USA
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Zhao X, Jones A, Olson KR, Peng K, Wehrman T, Park A, Mallari R, Nebalasca D, Young SW, Xiao SH. A homogeneous enzyme fragment complementation-based beta-arrestin translocation assay for high-throughput screening of G-protein-coupled receptors. ACTA ACUST UNITED AC 2008; 13:737-47. [PMID: 18660457 DOI: 10.1177/1087057108321531] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
G-protein-coupled receptors (GPCRs) represent one of the largest gene families in the human genome and have long been regarded as valuable targets for small-molecule drugs. The authors describe a new functional assay that directly monitors GPCR activation. It is based on the interaction between beta-arrestin and ligand-activated GPCRs and uses enzyme fragment complementation technology. In this format, a GPCR of interest is fused to a small (approximately 4 kDa), optimized alpha fragment peptide (termed ProLink) derived from beta-galactosidase, and beta-arrestin is fused to an N-terminal deletion mutant of beta-galactosidase (termed the enzyme acceptor [EA]). Upon activation of the receptor, the beta-arrestin-EA fusion protein binds the activated GPCR. This interaction drives enzyme fragment complementation, resulting in an active beta-galactosidase enzyme, and thus GPCR activation can be determined by quantifying beta-galactosidase activity. In this report, the authors demonstrate the utility of this technology to monitor GPCR activation and validate the approach using a Galphai-coupled GPCR, somatostatin receptor 2. Potential application to high-throughput screens in both agonist and antagonist screening modes is exemplified.
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Affiliation(s)
- Xiaoning Zhao
- Lead Discovery Department, Chemistry Research and Discovery, Amgen, Inc., South San Francisco, California 94080, USA.
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Molina-Hernndez A, Velasco I. Histamine induces neural stem cell proliferation and neuronal differentiation by activation of distinct histamine receptors. J Neurochem 2008; 106:706-17. [DOI: 10.1111/j.1471-4159.2008.05424.x] [Citation(s) in RCA: 68] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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Tian Y, Lee MM, Yung LY, Allen RA, Slocombe PM, Twomey BM, Wong YH. Differential involvement of Gα16 in CC chemokine-induced stimulation of phospholipase Cβ, ERK, and chemotaxis. Cell Signal 2008; 20:1179-89. [DOI: 10.1016/j.cellsig.2008.02.014] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2007] [Revised: 02/05/2008] [Accepted: 02/13/2008] [Indexed: 01/27/2023]
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Gouwy M, Struyf S, Noppen S, Schutyser E, Springael JY, Parmentier M, Proost P, Van Damme J. Synergy between coproduced CC and CXC chemokines in monocyte chemotaxis through receptor-mediated events. Mol Pharmacol 2008; 74:485-95. [PMID: 18469140 DOI: 10.1124/mol.108.045146] [Citation(s) in RCA: 98] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
CC and CXC chemokines coinduced in fibroblasts and leukocytes by cytokines and microbial agents determine the number of phagocytes infiltrating into inflamed tissues. Interleukin-8/CXCL8 and stromal cell-derived factor-1/CXCL12 significantly and dose-dependently increased the migration of monocytes, expressing the corresponding CXC chemokine receptors CXCR2 and CXCR4, toward suboptimal concentrations of the monocyte chemotactic proteins CCL2 or CCL7. These findings were confirmed using different chemotaxis assays and monocytic THP-1 cells. In contrast, the combination of two CC chemokines (CCL2 plus CCL7) or two CXC chemokines (CXCL8 plus CXCL12) did not provide synergy in monocyte chemotaxis. These data show that chemokines competing for related receptors and using similar signaling pathways do not synergize. Receptor heterodimerization is probably not essential for chemokine synergy as shown in CXCR4/CCR2 cotransfectants. It is noteworthy that CCL2 mediated extracellular signal-regulated kinase 1/2 phosphorylation and calcium mobilization was significantly enhanced by CXCL8 in monocytes, indicating cooperative downstream signaling pathways during enhanced chemotaxis. Moreover, in contrast to intact CXCL12, truncated CXCL12(3-68), which has impaired receptor signaling capacity but can still desensitize CXCR4, was unable to synergize with CCL2 in monocytic cell migration. Furthermore, AMD3100 and RS102895, specific CXCR4 and CCR2 inhibitors, respectively, reduced the synergistic effect between CCL2 and CXCL12 significantly. These data indicate that for synergistic interaction between chemokines binding and signaling of the two chemokines via their proper receptors is necessary.
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Affiliation(s)
- Mieke Gouwy
- Laboratory of Molecular Immunology, Rega Institute, University of Leuven, Minderbroedersstraat 10, B-3000 Leuven, Belgium
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Raghuwanshi SK, Nasser MW, Chen X, Strieter RM, Richardson RM. Depletion of beta-arrestin-2 promotes tumor growth and angiogenesis in a murine model of lung cancer. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2008; 180:5699-706. [PMID: 18390755 DOI: 10.4049/jimmunol.180.8.5699] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Arrestins are adaptor/scaffold proteins that complex with activated and phosphorylated G protein-coupled receptor to terminate G protein activation and signal transduction. These complexes also mediate downstream signaling, independently of G protein activation. We have previously shown that beta-arrestin-2 (betaarr2) depletion promotes CXCR2-mediated cellular signaling, including angiogenesis and excisional wound closure. This study was designed to investigate the role of betaarr2 in tumorigenesis using a murine model of lung cancer. To that end, heterotopic murine Lewis lung cancer and tail vein metastasis tumor model systems in betaarr2-deficient mice (betaarr2(-/-)) and control littermates (betaarr2(+/+)) were used. betaarr2(-/-) mice exhibited a significant increase in Lewis lung cancer tumor growth and metastasis relative to betaarr2(+/+) mice. This correlated with decreased number of tumor-infiltrating lymphocytes but with elevated levels of the ELR(+) chemokines (CXCL1/keratinocyte-derived chemokine and CXCL2/MIP-2), vascular endothelial growth factor, and microvessel density. NF-kappaB activity was also enhanced in betaarr2(-/-) mice, whereas hypoxia-inducible factor-1alpha expression was decreased. Inhibition of CXCR2 or NF-kappaB reduced tumor growth in both betaarr2(-/-) and betaarr2(+/+) mice. NF-kappaB inhibition also decreased ELR(+) chemokines and vascular endothelial growth factor expression. Altogether, the data suggest that betaarr2 modulates tumorigenesis by regulating inflammation and angiogenesis through activation of CXCR2 and NF-kappaB.
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Affiliation(s)
- Sandeep K Raghuwanshi
- Julius L. Chambers Biomedical/Biotechnology Research Institute, Department of Biology, North Carolina Central University, Durham, NC 27707, USA
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40
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Chemokines and cancer: migration, intracellular signalling and intercellular communication in the microenvironment. Biochem J 2008; 409:635-49. [DOI: 10.1042/bj20071493] [Citation(s) in RCA: 206] [Impact Index Per Article: 12.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Inappropriate chemokine/receptor expression or regulation is linked to many diseases, especially those characterized by an excessive cellular infiltrate, such as rheumatoid arthritis and other inflammatory disorders. There is now overwhelming evidence that chemokines are also involved in the progression of cancer, where they function in several capacities. First, specific chemokine–receptor pairs are involved in tumour metastasis. This is not surprising, in view of their role as chemoattractants in cell migration. Secondly, chemokines help to shape the tumour microenvironment, often in favour of tumour growth and metastasis, by recruitment of leucocytes and activation of pro-inflammatory mediators. Emerging evidence suggests that chemokine receptor signalling also contributes to survival and proliferation, which may be particularly important for metastasized cells to adapt to foreign environments. However, there is considerable diversity and complexity in the chemokine network, both at the chemokine/receptor level and in the downstream signalling pathways they couple into, which may be key to a better understanding of how and why particular chemokines contribute to cancer growth and metastasis. Further investigation into these areas may identify targets that, if inhibited, could render cancer cells more susceptible to chemotherapy.
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41
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Shi G, Partida-Sánchez S, Misra RS, Tighe M, Borchers MT, Lee JJ, Simon MI, Lund FE. Identification of an alternative G{alpha}q-dependent chemokine receptor signal transduction pathway in dendritic cells and granulocytes. ACTA ACUST UNITED AC 2007; 204:2705-18. [PMID: 17938235 PMCID: PMC2118484 DOI: 10.1084/jem.20071267] [Citation(s) in RCA: 62] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
CD38 controls the chemotaxis of leukocytes to some, but not all, chemokines, suggesting that chemokine receptor signaling in leukocytes is more diverse than previously appreciated. To determine the basis for this signaling heterogeneity, we examined the chemokine receptors that signal in a CD38-dependent manner and identified a novel "alternative" chemokine receptor signaling pathway. Similar to the "classical" signaling pathway, the alternative chemokine receptor pathway is activated by Galpha(i2)-containing Gi proteins. However, unlike the classical pathway, the alternative pathway is also dependent on the Gq class of G proteins. We show that Galpha(q)-deficient neutrophils and dendritic cells (DCs) make defective calcium and chemotactic responses upon stimulation with N-formyl methionyl leucyl phenylalanine and CC chemokine ligand (CCL) 3 (neutrophils), or upon stimulation with CCL2, CCL19, CCL21, and CXC chemokine ligand (CXCL) 12 (DCs). In contrast, Galpha(q)-deficient T cell responses to CXCL12 and CCL19 remain intact. Thus, the alternative chemokine receptor pathway controls the migration of only a subset of cells. Regardless, the novel alternative chemokine receptor signaling pathway appears to be critically important for the initiation of inflammatory responses, as Galpha(q) is required for the migration of DCs from the skin to draining lymph nodes after fluorescein isothiocyanate sensitization and the emigration of monocytes from the bone marrow into inflamed skin after contact sensitization.
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Affiliation(s)
- Guixiu Shi
- Trudeau Institute, Saranac Lake, NY 12983, USA
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42
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Paruch S, Heinis M, Lemay J, Hoeffel G, Marañón C, Hosmalin A, Périanin A. CCR5 signaling through phospholipase D involves p44/42 MAP-kinases and promotes HIV-1 LTR-directed gene expression. FASEB J 2007; 21:4038-46. [PMID: 17627030 DOI: 10.1096/fj.06-7325com] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
The chemokine receptor CCR5 plays an important role as an entry gate for the human immunodeficiency virus-1 (HIV-1) and for viral postentry events. Among signal transducers used by chemoattractant receptors, the phosphatidylcholine-specific phospholipase D (PLD) produces large amounts of second messengers in most cell types. However, the relevance of PLD isoforms to CCR5 signaling and HIV-1 infection process remains unexplored. We show here that CCR5 activation by MIP-1beta in HeLa-MAGI cells triggered a rapid and substantial PLD activity, as assessed by mass choline production. This activity required the activation of ERK1/2-MAP kinases and involved both PLD1 and PLD2. MIP-1beta also promoted the activation of an HIV-1 long terminal repeat (LTR) by the transactivator Tat in HeLa P4.2 cells through a process involving ERK1/2. Expression of wild-type and catalytically inactive PLDs dramatically boosted and inhibited the LTR activation, respectively, without altering Tat expression. Wild-type and inactive PLDs also respectively potentiated and inhibited HIV-1(BAL) replication in MAGI cells. Finally, in monocytic THP-1 cells, antisense oligonucleotides to both PLDs dramatically inhibited the HIV-1 replication. Thus, PLD is activated downstream of ERK1/2 upon CCR5 activation and plays a major role in promoting HIV-1 LTR transactivation and virus replication, which may open novel perspectives to anti-HIV-1 strategies.
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Affiliation(s)
- Sylvain Paruch
- Institut Cochin, Université Paris Descartes, CNRS (UMR 8104), Paris, France
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43
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Leach K, Charlton SJ, Strange PG. Analysis of second messenger pathways stimulated by different chemokines acting at the chemokine receptor CCR5. Biochem Pharmacol 2007; 74:881-90. [PMID: 17645873 DOI: 10.1016/j.bcp.2007.06.019] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2007] [Revised: 06/14/2007] [Accepted: 06/14/2007] [Indexed: 10/23/2022]
Abstract
The chemokine receptor, CCR5, responds to several chemokines leading to changes in activity in several signalling pathways. Here, we investigated the ability of different chemokines to provide differential activation of pathways. The effects of five CC chemokines acting at CCR5 were investigated for their ability to inhibit forskolin-stimulated 3'-5'-cyclic adenosine monophosphate (cAMP) accumulation and to stimulate Ca(2+) mobilisation in Chinese hamster ovary (CHO) cells expressing CCR5. Macrophage inflammatory protein 1alpha (D26A) (MIP-1alpha (D26A), CCL3 (D26A)), regulated on activation, normal T-cell expressed and secreted (RANTES, CCL5), MIP-1beta (CCL4) and monocyte chemoattractant protein 2 (MCP-2, CCL8) were able to inhibit forskolin-stimulated cAMP accumulation, whilst MCP-4 (CCL13) could not elicit a response. CCL3 (D26A), CCL4, CCL5, CCL8 and CCL13 were able to stimulate Ca(2+) mobilisation through CCR5, although CCL3 (D26A) and CCL5 exhibited biphasic concentration-response curves. The Ca(2+) responses induced by CCL4, CCL5, CCL8 and CCL13 were abolished by pertussis toxin, whereas the response to CCL3 (D26A) was only partially inhibited by pertussis toxin, indicating G(i/o)-independent signalling induced by this chemokine. Although the rank order of potency of chemokines was similar between the two assays, certain chemokines displayed different pharmacological profiles in cAMP inhibition and Ca(2+) mobilisation assays. For instance, whilst CCL13 could not inhibit forskolin-stimulated cAMP accumulation, this chemokine was able to induce Ca(2+) mobilisation via CCR5. It is concluded that different chemokines acting at CCR5 can induce different pharmacological responses, which may account for the broad spectrum of chemokines that can act at CCR5.
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Affiliation(s)
- K Leach
- School of Pharmacy, University of Reading, Whiteknights, PO Box 228, Reading RG6 6AJ, United Kingdom
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44
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Clerici C. A new mechanism for respiratory syncytial virus-induced beta2-adrenergic receptor insensitivity. Am J Physiol Lung Cell Mol Physiol 2007; 293:L279-80. [PMID: 17545486 DOI: 10.1152/ajplung.00205.2007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
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45
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Thompson BD, Jin Y, Wu KH, Colvin RA, Luster AD, Birnbaumer L, Wu MX. Inhibition of G alpha i2 activation by G alpha i3 in CXCR3-mediated signaling. J Biol Chem 2007; 282:9547-9555. [PMID: 17289675 PMCID: PMC2366813 DOI: 10.1074/jbc.m610931200] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
G protein-coupled receptors (GPCRs) convey extracellular stimulation into dynamic intracellular action, leading to the regulation of cell migration and differentiation. T lymphocytes express G alpha(i2) and G alpha(i3), two members of the G alpha(i/o) protein family, but whether these two G alpha(i) proteins have distinguishable roles guiding T cell migration remains largely unknown because of a lack of member-specific inhibitors. This study details distinct G alpha(i2) and G alpha(i3) effects on chemokine receptor CXCR3-mediated signaling. Our data showed that G alpha(i2) was indispensable for T cell responses to three CXCR3 ligands, CXCL9, CXCL10, and CXCL11, as the lack of G alpha(i2) abolished CXCR3-stimulated migration and guanosine 5'-3-O-(thio)triphosphate (GTPgammaS) incorporation. In sharp contrast, T cells isolated from G alpha(i3) knock-out mice displayed a significant increase in both GTPgammaS incorporation and migration as compared with wild type T cells when stimulated with CXCR3 agonists. The increased GTPgammaS incorporation was blocked by G alpha(i3) protein in a dose-dependent manner. G alpha(i3)-mediated blockade of G alpha(i2) activation did not result from G alpha(i3) activation, but instead resulted from competition or steric hindrance of G alpha(i2) interaction with the CXCR3 receptor via the N terminus of the second intracellular loop. A mutation in this domain abrogated not only G alpha(i2) activation induced by a CXCR3 agonist but also the interaction of G alpha(i3) to the CXCR3 receptor. These findings reveal for the first time an interplay of G alpha(i) proteins in transmitting G protein-coupled receptor signals. This interplay has heretofore been masked by the use of pertussis toxin, a broad inhibitor of the G alpha(i/o) protein family.
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MESH Headings
- Animals
- Cells, Cultured
- Chemokine CXCL10
- Chemokine CXCL11
- Chemokine CXCL9
- Chemokines, CXC/metabolism
- Female
- GTP-Binding Protein alpha Subunit, Gi2/antagonists & inhibitors
- GTP-Binding Protein alpha Subunit, Gi2/deficiency
- GTP-Binding Protein alpha Subunit, Gi2/metabolism
- GTP-Binding Protein alpha Subunit, Gi2/physiology
- GTP-Binding Protein alpha Subunits, Gi-Go/deficiency
- GTP-Binding Protein alpha Subunits, Gi-Go/genetics
- GTP-Binding Protein alpha Subunits, Gi-Go/metabolism
- GTP-Binding Protein alpha Subunits, Gi-Go/physiology
- Male
- Mice
- Mice, Inbred C57BL
- Mice, Knockout
- Receptors, CXCR3
- Receptors, Chemokine/metabolism
- Receptors, Chemokine/physiology
- Signal Transduction/genetics
- Signal Transduction/physiology
- T-Lymphocytes/immunology
- T-Lymphocytes/metabolism
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Affiliation(s)
- Brian D Thompson
- Wellman Center for Photomedicine, Department of Dermatology, Harvard Medical School, Massachusetts General Hospital, Boston, Massachusetts 02114
| | - Yongzhu Jin
- Wellman Center for Photomedicine, Department of Dermatology, Harvard Medical School, Massachusetts General Hospital, Boston, Massachusetts 02114
| | - Kevin H Wu
- Wellman Center for Photomedicine, Department of Dermatology, Harvard Medical School, Massachusetts General Hospital, Boston, Massachusetts 02114
| | - Richard A Colvin
- Center for Immunology and Inflammatory Diseases, Division of Rheumatology, Allergy and Immunology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts 02114
| | - Andrew D Luster
- Center for Immunology and Inflammatory Diseases, Division of Rheumatology, Allergy and Immunology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts 02114
| | - Lutz Birnbaumer
- NIEHS, Transmembrane Signaling Group, Laboratory of Signal Transduction, National Institutes of Health, Research Triangle Park, North Carolina 27709
| | - Mei X Wu
- Wellman Center for Photomedicine, Department of Dermatology, Harvard Medical School, Massachusetts General Hospital, Boston, Massachusetts 02114.
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46
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Green SR, Han KH, Chen Y, Almazan F, Charo IF, Miller YI, Quehenberger O. The CC Chemokine MCP-1 Stimulates Surface Expression of CX3CR1 and Enhances the Adhesion of Monocytes to Fractalkine/CX3CL1 via p38 MAPK. THE JOURNAL OF IMMUNOLOGY 2006; 176:7412-20. [PMID: 16751386 DOI: 10.4049/jimmunol.176.12.7412] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
The membrane-anchored form of CX3CL1 has been proposed as a novel adhesion protein for leukocytes. This functional property of CX3CL1 is mediated through CX3CR1, a chemokine receptor expressed predominantly on circulating white blood cells. Thus far, it is still uncertain at what stage of the trafficking process CX3CR1 becomes importantly involved and how the CX3CR1-dependent adhesion of leukocytes is regulated during inflammation. The objective of this study was to examine the functional effects of chemokine stimulation on CX3CR1-mediated adhesion of human monocytes. Consistent with previous reports, our data indicate that the activity of CX3CR1 on resting monocytes is sufficient to mediate cell adhesion to CX3CL1. However, the basal, nonstimulated adhesion activity is low, and we hypothesized that like the integrins, CX3CR1 may require a preceding activation step to trigger firm leukocyte adhesion. Compatible with this hypothesis, stimulation of monocytes with MCP-1 significantly increased their adhesion to immobilized CX3CL1, under both static and physiological flow conditions. The increase of the adhesion activity was mediated through CCR2-dependent signaling and obligatory activation of the p38 MAPK pathway. Stimulation with MCP-1 also induced a rapid increase of CX3CR1 protein on the cell surface. Inhibition of the p38 MAPK pathway prevented this increase of CX3CR1 surface expression and blunted the effect of MCP-1 on cell adhesion, indicating a causal link between receptor surface density and adhesion activity. Together, our data suggest that a chemokine signal is required for firm CX3CR1-dependent adhesion and demonstrate that CCR2 is an important regulator of CX3CL1-dependent leukocyte adhesion.
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MESH Headings
- Animals
- Antigen Presentation
- CX3C Chemokine Receptor 1
- Cell Adhesion/drug effects
- Cell Adhesion/immunology
- Cell Line, Tumor
- Chemokine CCL2/antagonists & inhibitors
- Chemokine CCL2/physiology
- Chemokine CX3CL1
- Chemokines, CX3C/antagonists & inhibitors
- Chemokines, CX3C/metabolism
- Chemokines, CX3C/physiology
- Extracellular Signal-Regulated MAP Kinases/antagonists & inhibitors
- Humans
- Membrane Proteins/antagonists & inhibitors
- Membrane Proteins/immunology
- Membrane Proteins/metabolism
- Membrane Proteins/physiology
- Mice
- Monocytes/enzymology
- Monocytes/immunology
- Monocytes/metabolism
- Pertussis Toxin/physiology
- Protein Kinase Inhibitors/pharmacology
- Receptors, CCR2
- Receptors, Chemokine/biosynthesis
- Receptors, Chemokine/deficiency
- Receptors, Chemokine/genetics
- Receptors, Chemokine/metabolism
- Receptors, Chemokine/physiology
- Signal Transduction/genetics
- Signal Transduction/immunology
- p38 Mitogen-Activated Protein Kinases/antagonists & inhibitors
- p38 Mitogen-Activated Protein Kinases/physiology
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Affiliation(s)
- Simone R Green
- Department of Medicine, University of California, San Diego, La Jolla, 92093, USA
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47
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Moscova M, Marsh DJ, Baxter RC. Protein chip discovery of secreted proteins regulated by the phosphatidylinositol 3-kinase pathway in ovarian cancer cell lines. Cancer Res 2006; 66:1376-83. [PMID: 16452192 DOI: 10.1158/0008-5472.can-05-2666] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Ovarian cancer has the highest mortality among the gynecologic malignancies. The phosphatidylinositol 3-kinase (PI3K) pathway is frequently activated, leading to increased cell survival. This study aimed to identify secreted proteins regulated by the PI3K pathway in ovarian cancer cell lines. Surface-enhanced laser desorption-ionization time-of-flight mass spectrometry with cation-exchange protein-chips was used to analyze secreted proteins from five ovarian cancer cell lines (SKOV-3, PE01, OVCAR-3, OV167, and OV207). To activate the PI3K pathway, cells were treated with 50 ng/mL epidermal growth factor (EGF) with or without 10 micromol/L LY294002, a PI3K inhibitor. Proteins induced by EGF and inhibited by LY294002, in the m/z range 7,500 to 9,500, were purified chromatographically, identified by peptide mass fingerprinting and NH(2)-terminal sequencing, and confirmed by immunodepletion. Two immunologically related proteins, m/z approximately 8,385 and 8,922, were identified as truncated and intact forms, respectively, of interleukin 8, a chemokine previously shown to be elevated in serum of ovarian cancer patients. Another protein, m/z 7,866, was identified as CXC chemokine ligand 1 (CXCL1) or GRO-alpha, a chemokine associated with melanoma formation and some epithelial cancers. EGF-stimulated CXCL1 levels were variably decreased by mitogen-activated protein kinase (MAPK)/extracellular signal-regulated kinase kinase and p38 MAPK inhibition in the five cell lines, but only LY294002 fully reversed the EGF effect in all cell lines. Immunoreactive CXCL1 levels in 160 conditioned media were highly correlated with corresponding peak intensities at m/z 7,866 by mass spectrometry, indicating the quantitative nature of these analyses. We conclude that proteomic analysis of cell models of human disease may facilitate the discovery of pathway-dependent proteins.
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Affiliation(s)
- Michelle Moscova
- Laboratory of Cellular and Diagnostic Proteomics, Kolling Institute of Medical Research, University of Sydney, Royal North Shore Hospital, St. Leonards, New South Wales 2065, Australia
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48
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Banisadr G, Gosselin RD, Mechighel P, Rostène W, Kitabgi P, Mélik Parsadaniantz S. Constitutive neuronal expression of CCR2 chemokine receptor and its colocalization with neurotransmitters in normal rat brain: functional effect of MCP-1/CCL2 on calcium mobilization in primary cultured neurons. J Comp Neurol 2006; 492:178-92. [PMID: 16196033 DOI: 10.1002/cne.20729] [Citation(s) in RCA: 111] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Chemokines and their receptors are well described in the immune system, where they promote cell migration and activation. In the central nervous system, chemokine has been implicated in neuroinflammatory processes. However, an increasing number of evidence suggests that they have regulatory functions in the normal nervous system, where they could participate in cell communication. In this work, using a semiquantitative immunohistochemistry approach, we provide the first neuroanatomical mapping of constitutive neuronal CCR2 localization. Neuronal expression of CCR2 was observed in the anterior olfactory nucleus, cerebral cortex, hippocampal formation, caudate putamen, globus pallidus, supraoptic and paraventricular hypothalamic nuclei, amygdala, substantia nigra, ventral tegmental area, and in the brainstem and cerebellum. These data are largely in accordance with results obtained using quantitative autoradiography with [(125)I]MCP-1/CCL2 and RT-PCR CCR2 mRNA analysis. Furthermore, using dual fluorescent immunohistochemistry we studied the chemical phenotype of labeled neurons and demonstrated the coexistence of CCR2 with classical neurotransmitters. Indeed, localization of CCR2 immunostaining is observed in dopaminergic neurons in the substantia nigra pars compacta and in the ventral tegmental area as well as in cholinergic neurons in the substantia innominata and caudate putamen. Finally, we show that the preferential CCR2 ligand, MCP-1/CCL2, elicits Ca(2+) transients in primary cultured neurons from various rat brain regions including the cortex, hippocampus, hypothalamus, and mesencephalon. In conclusion, the constitutive neuronal CCR2 expression in selective brain structures suggests that this receptor could be involved in neuronal communication and possibly associated with cholinergic and dopaminergic neurotransmission and related disorders.
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Affiliation(s)
- Ghazal Banisadr
- Institut National de la Santé et de la Recherche Médicale U732-Université Pierre et Marie Curie; Hôpital Saint-Antoine, Paris Cedex 12, France
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49
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Abstract
Leukocyte infiltration into the joint space and tissues is an essential component of the pathogenesis of rheumatoid arthritis (RA). In this review, we will summarize the current understanding of the mechanisms of leukocyte trafficking into the synovium, focusing on the role of adhesion molecules, chemokines, and chemokine receptors in synovial autoimmune inflammation. The process by which a circulating leukocyte decides to migrate into the synovium is highly regulated and involves the capture, firm adhesion, and transmigration of cells across the endothelial monolayer. Adhesion molecules and chemokine signals function in concert to mediate this process and to organize leukocytes into distinct structures within the synovium. Chemokines play a key regulatory role in organ-specific leukocyte trafficking and activation by affecting integrin activation, chemotaxis, effector cell function, and cell survival. Consequently, chemokines, their receptors, and downstream signal transduction molecules are attractive therapeutic targets for RA.
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Affiliation(s)
- Teresa K Tarrant
- Department of Medicine, Division of Rheumatology, Allergy, and Immunology, Thurston Arthritis Research Center, University of North Carolina, 3330 Thurston Bldg., CB#7280, Chapel Hill, NC 27599, USA
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50
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Su Y, Raghuwanshi SK, Yu Y, Nanney LB, Richardson RM, Richmond A. Altered CXCR2 signaling in beta-arrestin-2-deficient mouse models. THE JOURNAL OF IMMUNOLOGY 2005; 175:5396-402. [PMID: 16210646 PMCID: PMC2668249 DOI: 10.4049/jimmunol.175.8.5396] [Citation(s) in RCA: 70] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
CXCR2 is a G-protein-coupled receptor (GPCR) that binds the CXC chemokines, CXCL1-3 and CXCL5-8, and induces intracellular signals associated with chemotaxis. Many adaptor proteins are actively involved in the sequestration, internalization, and trafficking of CXCR2 and transduction of agonist-induced intracellular signaling. We have previously shown that adaptor protein beta-arrestin-2 (betaarr2) plays a crucial role in transducing signals mediated through CXCR2. To further investigate the role of betaarr2 on CXCR2-mediated signaling during acute inflammation, zymosan-induced neutrophils were isolated from peritoneal cavities of betaarr2-deficient (betaarr2(-/-)) and their wild-type (betaarr2(+/+)) littermate mice, and neutrophil CXCR2 signaling activities were determined by measurement of Ca(2+) mobilization, receptor internalization, GTPase activity, and superoxide anion production. The results showed that the deletion of betaarr2 resulted in increased Ca(2+) mobilization, superoxide anion production, and GTPase activity in neutrophils, but decreased receptor internalization relative to wild-type mice. Two animal models, the dorsal air pouch model and the excisional wound healing model, were used to further study the in vivo effects of betaarr2 on CXCR2-mediated neutrophil chemotaxis and on cutaneous wound healing. Surprisingly, the recruitment of neutrophils was increased in response to CXCL1 in the air pouch model and in the excisional wound beds of betaarr2(-/-) mice. Wound re-epithelialization was also significantly faster in betaarr2(-/-) mice than in betaarr2(+/+) mice. Taken together, the data indicate that betaarr2 is a negative regulator for CXCR2 in vivo signaling.
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Affiliation(s)
- Yingjun Su
- Department of Cancer Biology, Vanderbilt University School of Medicine, Nashville, TN 37232
| | - Sandeep K. Raghuwanshi
- Julius L. Chambers Biomedical/Biotechnology Research Institute, North Carolina Central University, Durham, NC 27707
- Department of Biochemistry, Meharry Medical College, Nashville, TN 37208
| | - Yingchun Yu
- Department of Cancer Biology, Vanderbilt University School of Medicine, Nashville, TN 37232
| | - Lillian B. Nanney
- Department of Plastic Surgery, Vanderbilt University School of Medicine, Nashville, TN 37232
| | - Ricardo M. Richardson
- Julius L. Chambers Biomedical/Biotechnology Research Institute, North Carolina Central University, Durham, NC 27707
- Department of Biochemistry, Meharry Medical College, Nashville, TN 37208
| | - Ann Richmond
- Department of Veterans Affairs, Nashville, TN 37212
- Department of Cancer Biology, Vanderbilt University School of Medicine, Nashville, TN 37232
- Address correspondence and reprint requests to Dr. Ann Richmond, Department of Cancer Biology, Vanderbilt University School of Medicine, Nashville, TN 37232. E-mail address:
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