Ezrin and moesin co-localise with ICAM-1 in brain endothelial cells but are not directly associated

Brain Res Mol Brain Res. 2002 Sep 30;105(1-2):47-59. doi: 10.1016/s0169-328x(02)00392-3.

Abstract

The precise mechanism by which ICAM-1 transduces signals from adherent lymphocytes remains elusive. The ERM proteins ezrin and moesin were found to strongly co-localise with both ICAM-1 and F-actin in brain microvascular endothelial cells suggesting a potential role in mediating ICAM-1 signalling. Such strong co-localisation was maintained following treatment of cells with cytochalasin D, which inhibits actin polymerization and which is capable of inhibiting ICAM-1-induced signalling. Cross-linking of ICAM-1 demonstrated ICAM-1 clustering which no longer associated with ezrin or moesin. In addition immunoprecipitation analysis revealed that ICAM-1 was incapable of precipitating ERM proteins under conditions where ezrin was efficiently precipitated with anti-ICAM-2 antibodies. Fractionation of cell lysates on sucrose density gradients shows ICAM-1 and ezrin to sediment at different densities, whereas ICAM-2 co-sediments with ezrin. Together these data suggest that ICAM-1 is not directly associated with ezrin and moesin in brain microvascular endothelial cells.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Actins / immunology
  • Actins / metabolism
  • Animals
  • Antigens, CD / immunology
  • Antigens, CD / metabolism
  • Blood Proteins / immunology
  • Blood Proteins / metabolism
  • Blood-Brain Barrier / immunology*
  • Brain / blood supply
  • Brain / immunology*
  • Brain / metabolism
  • Cell Adhesion / immunology*
  • Cell Adhesion Molecules / immunology
  • Cell Adhesion Molecules / metabolism
  • Cells, Cultured
  • Chemotaxis, Leukocyte / immunology
  • Cytochalasin D / pharmacology
  • Cytoskeletal Proteins / immunology
  • Cytoskeletal Proteins / metabolism
  • Cytoskeleton / immunology
  • Cytoskeleton / metabolism
  • Encephalitis / immunology
  • Endothelium, Vascular / immunology*
  • Endothelium, Vascular / metabolism
  • Immunologic Surveillance / immunology
  • Intercellular Adhesion Molecule-1 / immunology*
  • Intercellular Adhesion Molecule-1 / metabolism
  • Membrane Proteins / immunology
  • Membrane Proteins / metabolism
  • Microfilament Proteins / immunology*
  • Microfilament Proteins / metabolism
  • Nucleic Acid Synthesis Inhibitors / pharmacology
  • Phosphoproteins / immunology*
  • Phosphoproteins / metabolism
  • Precipitin Tests
  • Rats
  • Signal Transduction / immunology
  • Vinculin / immunology
  • Vinculin / metabolism
  • rho GTP-Binding Proteins / immunology
  • rho GTP-Binding Proteins / metabolism

Substances

  • Actins
  • Antigens, CD
  • Blood Proteins
  • Cell Adhesion Molecules
  • Cytoskeletal Proteins
  • ICAM2 protein, human
  • Membrane Proteins
  • Microfilament Proteins
  • Nucleic Acid Synthesis Inhibitors
  • Phosphoproteins
  • ezrin
  • Vinculin
  • Intercellular Adhesion Molecule-1
  • moesin
  • radixin
  • Cytochalasin D
  • rho GTP-Binding Proteins