title: MIF interacts with CXCR7 to promote receptor internalization, ERK1/2 and ZAP-70 signaling, and lymphocyte chemotaxis.
abstract: Macrophage migration-inhibitory factor (MIF) is a pleiotropic cytokine with chemokine-like functions and is a mediator in numerous inflammatory conditions. Depending on the context, MIF signals through 1 or more of its receptors cluster of differentiation (CD)74, CXC-motif chemokine receptor (CXCR)2, and CXCR4. In addition, heteromeric receptor complexes have been identified. We characterized the atypical chemokine receptor CXCR7 as a novel receptor for MIF. MIF promoted human CXCR7 internalization up to 40%, peaking at 50-400 nM and 30 min, but CXCR7 internalization by MIF was not dependent on CXCR4. Yet, by coimmunoprecipitation, fluorescence microscopy, and a proximity ligation assay, CXCR7 was found to engage in MIF receptor complexes with CXCR4 and CD74, both after ectopic overexpression and in endogenous conditions in a human B-cell line. Receptor competition binding and coimmunoprecipitation studies combined with sulfo-SBED-biotin-transfer provided evidence for a direct interaction between MIF and CXCR7. Finally, we demonstrated MIF/CXCR7-mediated functional responses. Blockade of CXCR7 suppressed MIF-mediated ERK- and zeta-chain-associated protein kinase (ZAP)-70 activation (from 2.1- to 1.2-fold and from 2.5- to 1.6-fold, respectively) and fully abrogated primary murine B-cell chemotaxis triggered by MIF, but not by CXCL12. B cells from Cxcr7(-/-) mice exhibited an ablated transmigration response to MIF, indicating that CXCR7 is essential for MIF-promoted B-cell migration. Our findings provide biochemical and functional evidence that MIF is an alternative ligand of CXCR7 and suggest a functional role of the MIF-CXCR7 axis in B-lymphocyte migration.
authors.affiliation: *Institute of Biochemistry and Molecular Cell Biology, Institute of Biochemistry and Molecular Biology, and Interdisziplinäres Zentrum für Klinische Forschung (IZKF), Rhine-Westphalia Technical University of Aachen (RWTH), Aachen, Germany; Centre for Immunology and Infection, Department of Biology, University of York, York, United Kingdom; INSERM, Unité Mixte de Recherche-S 996, Laboratory of Excellence in Research on Medication and Innovative Therapeutics, Université Paris-Sud, Clamart, France; Medizinische Klinik III, Kardiologie und Kreislauferkrankungen, University of Tübingen, Tübingen, Germany; Institute for Cardiovascular Prevention, Klinikum der Universität München, and August-Lenz-Stiftung, Ludwig-Maximilians-Universität München, Munich, Germany; **Cardiovascular Research Institute Maastricht, Maastricht University, Maastricht, The Netherlands; and Deutches Zentrum für Herz-Kreislauf Forschung (DZHK), Partner Site Munich Heart Alliance, Munich, Germany.
authors.forename: Setareh
authors.initials: S
authors.lastname: Alampour-Rajabi
authors.affiliation: *Institute of Biochemistry and Molecular Cell Biology, Institute of Biochemistry and Molecular Biology, and Interdisziplinäres Zentrum für Klinische Forschung (IZKF), Rhine-Westphalia Technical University of Aachen (RWTH), Aachen, Germany; Centre for Immunology and Infection, Department of Biology, University of York, York, United Kingdom; INSERM, Unité Mixte de Recherche-S 996, Laboratory of Excellence in Research on Medication and Innovative Therapeutics, Université Paris-Sud, Clamart, France; Medizinische Klinik III, Kardiologie und Kreislauferkrankungen, University of Tübingen, Tübingen, Germany; Institute for Cardiovascular Prevention, Klinikum der Universität München, and August-Lenz-Stiftung, Ludwig-Maximilians-Universität München, Munich, Germany; **Cardiovascular Research Institute Maastricht, Maastricht University, Maastricht, The Netherlands; and Deutches Zentrum für Herz-Kreislauf Forschung (DZHK), Partner Site Munich Heart Alliance, Munich, Germany.
authors.forename: Omar
authors.initials: O
authors.lastname: El Bounkari
authors.affiliation: *Institute of Biochemistry and Molecular Cell Biology, Institute of Biochemistry and Molecular Biology, and Interdisziplinäres Zentrum für Klinische Forschung (IZKF), Rhine-Westphalia Technical University of Aachen (RWTH), Aachen, Germany; Centre for Immunology and Infection, Department of Biology, University of York, York, United Kingdom; INSERM, Unité Mixte de Recherche-S 996, Laboratory of Excellence in Research on Medication and Innovative Therapeutics, Université Paris-Sud, Clamart, France; Medizinische Klinik III, Kardiologie und Kreislauferkrankungen, University of Tübingen, Tübingen, Germany; Institute for Cardiovascular Prevention, Klinikum der Universität München, and August-Lenz-Stiftung, Ludwig-Maximilians-Universität München, Munich, Germany; **Cardiovascular Research Institute Maastricht, Maastricht University, Maastricht, The Netherlands; and Deutches Zentrum für Herz-Kreislauf Forschung (DZHK), Partner Site Munich Heart Alliance, Munich, Germany.
authors.forename: Antal
authors.initials: A
authors.lastname: Rot
authors.affiliation: *Institute of Biochemistry and Molecular Cell Biology, Institute of Biochemistry and Molecular Biology, and Interdisziplinäres Zentrum für Klinische Forschung (IZKF), Rhine-Westphalia Technical University of Aachen (RWTH), Aachen, Germany; Centre for Immunology and Infection, Department of Biology, University of York, York, United Kingdom; INSERM, Unité Mixte de Recherche-S 996, Laboratory of Excellence in Research on Medication and Innovative Therapeutics, Université Paris-Sud, Clamart, France; Medizinische Klinik III, Kardiologie und Kreislauferkrankungen, University of Tübingen, Tübingen, Germany; Institute for Cardiovascular Prevention, Klinikum der Universität München, and August-Lenz-Stiftung, Ludwig-Maximilians-Universität München, Munich, Germany; **Cardiovascular Research Institute Maastricht, Maastricht University, Maastricht, The Netherlands; and Deutches Zentrum für Herz-Kreislauf Forschung (DZHK), Partner Site Munich Heart Alliance, Munich, Germany.
authors.forename: Gerhard
authors.initials: G
authors.lastname: Müller-Newen
authors.affiliation: *Institute of Biochemistry and Molecular Cell Biology, Institute of Biochemistry and Molecular Biology, and Interdisziplinäres Zentrum für Klinische Forschung (IZKF), Rhine-Westphalia Technical University of Aachen (RWTH), Aachen, Germany; Centre for Immunology and Infection, Department of Biology, University of York, York, United Kingdom; INSERM, Unité Mixte de Recherche-S 996, Laboratory of Excellence in Research on Medication and Innovative Therapeutics, Université Paris-Sud, Clamart, France; Medizinische Klinik III, Kardiologie und Kreislauferkrankungen, University of Tübingen, Tübingen, Germany; Institute for Cardiovascular Prevention, Klinikum der Universität München, and August-Lenz-Stiftung, Ludwig-Maximilians-Universität München, Munich, Germany; **Cardiovascular Research Institute Maastricht, Maastricht University, Maastricht, The Netherlands; and Deutches Zentrum für Herz-Kreislauf Forschung (DZHK), Partner Site Munich Heart Alliance, Munich, Germany.
authors.forename: Françoise
authors.initials: F
authors.lastname: Bachelerie
authors.affiliation: *Institute of Biochemistry and Molecular Cell Biology, Institute of Biochemistry and Molecular Biology, and Interdisziplinäres Zentrum für Klinische Forschung (IZKF), Rhine-Westphalia Technical University of Aachen (RWTH), Aachen, Germany; Centre for Immunology and Infection, Department of Biology, University of York, York, United Kingdom; INSERM, Unité Mixte de Recherche-S 996, Laboratory of Excellence in Research on Medication and Innovative Therapeutics, Université Paris-Sud, Clamart, France; Medizinische Klinik III, Kardiologie und Kreislauferkrankungen, University of Tübingen, Tübingen, Germany; Institute for Cardiovascular Prevention, Klinikum der Universität München, and August-Lenz-Stiftung, Ludwig-Maximilians-Universität München, Munich, Germany; **Cardiovascular Research Institute Maastricht, Maastricht University, Maastricht, The Netherlands; and Deutches Zentrum für Herz-Kreislauf Forschung (DZHK), Partner Site Munich Heart Alliance, Munich, Germany.
authors.forename: Meinrad
authors.initials: M
authors.lastname: Gawaz
authors.affiliation: *Institute of Biochemistry and Molecular Cell Biology, Institute of Biochemistry and Molecular Biology, and Interdisziplinäres Zentrum für Klinische Forschung (IZKF), Rhine-Westphalia Technical University of Aachen (RWTH), Aachen, Germany; Centre for Immunology and Infection, Department of Biology, University of York, York, United Kingdom; INSERM, Unité Mixte de Recherche-S 996, Laboratory of Excellence in Research on Medication and Innovative Therapeutics, Université Paris-Sud, Clamart, France; Medizinische Klinik III, Kardiologie und Kreislauferkrankungen, University of Tübingen, Tübingen, Germany; Institute for Cardiovascular Prevention, Klinikum der Universität München, and August-Lenz-Stiftung, Ludwig-Maximilians-Universität München, Munich, Germany; **Cardiovascular Research Institute Maastricht, Maastricht University, Maastricht, The Netherlands; and Deutches Zentrum für Herz-Kreislauf Forschung (DZHK), Partner Site Munich Heart Alliance, Munich, Germany.
authors.forename: Christian
authors.initials: C
authors.lastname: Weber
authors.affiliation: *Institute of Biochemistry and Molecular Cell Biology, Institute of Biochemistry and Molecular Biology, and Interdisziplinäres Zentrum für Klinische Forschung (IZKF), Rhine-Westphalia Technical University of Aachen (RWTH), Aachen, Germany; Centre for Immunology and Infection, Department of Biology, University of York, York, United Kingdom; INSERM, Unité Mixte de Recherche-S 996, Laboratory of Excellence in Research on Medication and Innovative Therapeutics, Université Paris-Sud, Clamart, France; Medizinische Klinik III, Kardiologie und Kreislauferkrankungen, University of Tübingen, Tübingen, Germany; Institute for Cardiovascular Prevention, Klinikum der Universität München, and August-Lenz-Stiftung, Ludwig-Maximilians-Universität München, Munich, Germany; **Cardiovascular Research Institute Maastricht, Maastricht University, Maastricht, The Netherlands; and Deutches Zentrum für Herz-Kreislauf Forschung (DZHK), Partner Site Munich Heart Alliance, Munich, Germany.
authors.forename: Andreas
authors.initials: A
authors.lastname: Schober
authors.affiliation: *Institute of Biochemistry and Molecular Cell Biology, Institute of Biochemistry and Molecular Biology, and Interdisziplinäres Zentrum für Klinische Forschung (IZKF), Rhine-Westphalia Technical University of Aachen (RWTH), Aachen, Germany; Centre for Immunology and Infection, Department of Biology, University of York, York, United Kingdom; INSERM, Unité Mixte de Recherche-S 996, Laboratory of Excellence in Research on Medication and Innovative Therapeutics, Université Paris-Sud, Clamart, France; Medizinische Klinik III, Kardiologie und Kreislauferkrankungen, University of Tübingen, Tübingen, Germany; Institute for Cardiovascular Prevention, Klinikum der Universität München, and August-Lenz-Stiftung, Ludwig-Maximilians-Universität München, Munich, Germany; **Cardiovascular Research Institute Maastricht, Maastricht University, Maastricht, The Netherlands; and Deutches Zentrum für Herz-Kreislauf Forschung (DZHK), Partner Site Munich Heart Alliance, Munich, Germany jbernhagen@ukaachen.de.
authors.forename: Jürgen
authors.initials: J
authors.lastname: Bernhagen
mesh_terms: D000818:Animals; D001402:B-Lymphocytes / Q000166:cytology / Q000378:metabolism*; D045744:Cell Line, Tumor; D054377:Chemokine CXCL12 / Q000235:genetics / Q000378:metabolism; D002633:Chemotaxis / Q000502:physiology*; D006801:Humans; D019746:Intramolecular Oxidoreductases / Q000235:genetics / Q000378:metabolism*; D020935:MAP Kinase Signaling System / Q000502:physiology*; D008263:Macrophage Migration-Inhibitory Factors / Q000235:genetics / Q000378:metabolism*; D051379:Mice; D019950:Mitogen-Activated Protein Kinase 1 / Q000235:genetics / Q000378:metabolism; D048052:Mitogen-Activated Protein Kinase 3 / Q000235:genetics / Q000378:metabolism; D054387:Receptors, CXCR / Q000235:genetics / Q000378:metabolism*; D019718:Receptors, CXCR4 / Q000235:genetics / Q000378:metabolism; D051746:ZAP-70 Protein-Tyrosine Kinase / Q000235:genetics / Q000378:metabolism*
chemical_list: C501896:ACKR3 protein, human; C515255:CXCL12 protein, human; C527276:CXCR4 protein, human; C514936:CXCR4 protein, mouse; D054377:Chemokine CXCL12; C501897:Cmkor1 protein, mouse; C515256:Cxcl12 protein, mouse; D008263:Macrophage Migration-Inhibitory Factors; D054387:Receptors, CXCR; D019718:Receptors, CXCR4; D051746:ZAP-70 Protein-Tyrosine Kinase; C497261:ZAP70 protein, human; C497262:Zap70 protein, mouse; C535150:MAPK1 protein, human; D019950:Mitogen-Activated Protein Kinase 1; D048052:Mitogen-Activated Protein Kinase 3; D019746:Intramolecular Oxidoreductases; C515598:MIF protein, human; C076231:Mif protein, mouse
keywords: CD74; chemokine; chemokine receptor; cytokine; receptor complex