R. Tuteja et al., Augmentation of immune responses to hepatitis E virus ORF2 DNA vaccinationby codelivery cytokine genes, VIRAL IMMUN, 13(2), 2000, pp. 169-178
DNA vaccines encoding a viral structural protein have been shown to induce
antiviral immune responses and provide protection against subsequent viral
challenge. In the present study we show that DNA immunization with a plasmi
d expressing the hepatitis E virus ORF2 structural protein (pcDNA-ORF2) ind
uced low levels of long-lasting antibody responses in the murine model. The
use of plasmids expressing interleukin-2 (IL-2) and granulocyte-macrophage
colony-stimulating-factor (GM-CSF) in conjunction with pcDNA-ORF2 enhanced
the antibody responses generated by pORF-2. We further show that the immun
e responses generated by plasmid pcDNA-ORF2 can be boosted with virus-like
particles composed of the ORF2 protein expressed through a baculovirus expr
ession system.