Antibody-induced internalization of viral glycoproteins in pseudorabies virus-infected monocytes and role of the cytoskeleton: a confocal study

Vet Microbiol. 2002 Apr 22;86(1-2):51-7. doi: 10.1016/s0378-1135(01)00490-4.

Abstract

Addition of pseudorabies virus (PrV)-specific polyclonal immunoglobulins to PrV-infected monocytes induces internalization of plasma membrane anchored viral glycoproteins. This process may interfere with antibody-dependent cell lysis and resembles the well-studied physiological endocytosis process. A confocal study was designed to investigate whether the major cellular components, involved in physiological endocytosis (clathrin, actin, dynein and microtubules), play a role in this virological internalization process. In order to visualize the interaction of endosomes, which contain the internalized viral glycoproteins, with clathrin, actin, dynein and microtubules, a double labeling of viral glycoproteins and different cellular proteins was performed. Porcine monocytes were inoculated with the PrV-strain 89V87 at a multiplicity of infection of 50 for 13h. After the addition of FITC-labeled porcine polyclonal PrV-specific antibodies, cells were fixed with para-formaldehyde at different time points and afterwards permeabilized. The different cellular components were visualized with monoclonal antibodies and a Texas Red-conjugate, with the exception of actin, which was stained with phalloidin-Texas Red. The cells were analyzed by confocal microscopy. A clear co-localization was observed between the viral glycoproteins and clathrin and dynein during the internalization process. The microtubules were in close contact with the internalized vesicles. For actin no co-localization could be observed. It can be stated that clathrin, dynein and microtubules, important components during physiological endocytosis, are also of importance during the antibody-induced internalization of viral glycoproteins.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Actins / immunology
  • Animals
  • Antibodies, Viral / immunology*
  • Clathrin / immunology
  • Cytoskeleton / immunology*
  • Dyneins / immunology
  • Herpesvirus 1, Suid / immunology*
  • Leukocytes, Mononuclear / immunology*
  • Leukocytes, Mononuclear / metabolism
  • Leukocytes, Mononuclear / virology
  • Microscopy, Confocal
  • Microtubules / immunology
  • Pseudorabies / blood
  • Pseudorabies / immunology*
  • Pseudorabies / virology
  • Swine
  • Swine Diseases / blood
  • Swine Diseases / immunology*
  • Swine Diseases / virology
  • Viral Proteins / immunology*
  • Viral Proteins / metabolism

Substances

  • Actins
  • Antibodies, Viral
  • Clathrin
  • Viral Proteins
  • Dyneins