Overexpression of the rabies virus glycoprotein results in enhancement of apoptosis and antiviral immune response.
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.
Faber
Milosz
M
Department of Microbiology and Immunology, Center for Human Virology, Thomas Jefferson University, Philadelphia, Pennsylvania 19107, USA.
Pulmanausahakul
Rojjanaporn
R
Hodawadekar
Suchita S
SS
Spitsin
Sergei
S
McGettigan
James P
JP
Schnell
Matthias J
MJ
Dietzschold
Bernhard
B
D000199:Actins / Q000032:analysis; D000818:Animals; D000914:Antibodies, Viral / Q000097:blood; D000956:Antigens, Viral; D017209:Apoptosis; D002478:Cells, Cultured; D005260:Female; D005455:Fluorescent Antibody Technique; D006023:Glycoproteins / Q000096:biosynthesis* / Q000235:genetics / Q000276:immunology; D051379:Mice; D018613:Microscopy, Confocal; D016900:Neurofilament Proteins / Q000032:analysis; D009474:Neurons / Q000473:pathology / Q000821:virology; D019590:Nucleocapsid Proteins / Q000032:analysis; D011818:Rabies / Q000097:blood / Q000276:immunology* / Q000517:prevention & control; D011820:Rabies virus / Q000235:genetics / Q000276:immunology / Q000378:metabolism*; D011995:Recombination, Genetic; D014611:Vaccination / Q000379:methods; D014759:Viral Envelope Proteins / Q000096:biosynthesis* / Q000235:genetics / Q000276:immunology
D000199:Actins; D000914:Antibodies, Viral; D000956:Antigens, Viral; D006023:Glycoproteins; D016900:Neurofilament Proteins; D019590:Nucleocapsid Proteins; D014759:Viral Envelope Proteins; C064951:glycoprotein G, Rabies virus