Overexpression of the rabies virus glycoprotein results in enhancement of apoptosis and antiviral immune response

J Virol. 2002 Apr;76(7):3374-81. doi: 10.1128/jvi.76.7.3374-3381.2002.

Abstract

A recombinant rabies virus (RV) carrying two identical glycoprotein (G) genes (SPBNGA-GA) was constructed and used to determine the effect of RV G overexpression on cell viability and immunity. Immunoprecipitation analysis and flow cytometry showed that tissue culture cells infected with SPBNGA-GA produced, on average, twice as much RV G as cells infected with RV carrying only a single RV G gene (SPBNGA). The overexpression of RV G in SPBNGA-GA-infected NA cells was paralleled by a significant increase in caspase 3 activity followed by a marked decrease in mitochondrial respiration, neither of which was observed in SPBNGA-infected cells. Furthermore, fluorescence staining and confocal microscopy revealed an increased extent of apoptosis and markedly reduced neurofilament and F actin in SPBNGA-GA-infected primary neuron cultures compared with neuronal cells infected with SPBNGA, supporting the concept that RV G or motifs of the RV G gene trigger the apoptosis cascade. Mice immunized with SPBNGA-GA showed substantially higher antibody titers against the RV G and against the nucleoprotein than SPBNGA-immunized mice, suggesting that the speed or extent of apoptosis directly determines the magnitude of the antibody response.

Publication types

  • Comparative Study
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Actins / analysis
  • Animals
  • Antibodies, Viral / blood
  • Antigens, Viral*
  • Apoptosis
  • Cells, Cultured
  • Female
  • Fluorescent Antibody Technique
  • Glycoproteins / biosynthesis*
  • Glycoproteins / genetics
  • Glycoproteins / immunology
  • Mice
  • Microscopy, Confocal
  • Neurofilament Proteins / analysis
  • Neurons / pathology
  • Neurons / virology
  • Nucleocapsid Proteins / analysis
  • Rabies / blood
  • Rabies / immunology*
  • Rabies / prevention & control
  • Rabies virus / genetics
  • Rabies virus / immunology
  • Rabies virus / metabolism*
  • Recombination, Genetic
  • Vaccination / methods
  • Viral Envelope Proteins / biosynthesis*
  • Viral Envelope Proteins / genetics
  • Viral Envelope Proteins / immunology

Substances

  • Actins
  • Antibodies, Viral
  • Antigens, Viral
  • Glycoproteins
  • Neurofilament Proteins
  • Nucleocapsid Proteins
  • Viral Envelope Proteins
  • glycoprotein G, Rabies virus