@article{mbs:/content/journal/jgv/10.1099/0022-1317-83-12-2973, author = "Pontarollo, R. A. and Babiuk, L. A. and Hecker, R. and van Drunen Littel-van den Hurk, S.", title = "Augmentation of cellular immune responses to bovine herpesvirus-1 glycoprotein D by vaccination with CpG-enhanced plasmid vectors", journal= "Journal of General Virology", year = "2002", volume = "83", number = "12", pages = "2973-2981", doi = "https://doi.org/10.1099/0022-1317-83-12-2973", url = "https://www.microbiologyresearch.org/content/journal/jgv/10.1099/0022-1317-83-12-2973", publisher = "Microbiology Society", issn = "1465-2099", type = "Journal Article", abstract = "The potential of CpG-enhanced plasmid DNA vectors encoding a truncated secreted form of bovine herpesvirus-1 (BHV-1) glycoprotein D (tgD) to induce enhanced immune responses in cattle was investigated. We created tgD expression plasmids containing 0, 40 or 88 copies of the hexamer 5’ GTCGTT 3’, a known pan-activating CpG motif in several species. The total tgD-specific IgG titre of calves immunized with these plasmids did not correlate with the CpG content of the plasmid backbone. However, the pBISIA88-tgD-vaccinated group showed a significantly lower IgG1:IgG2 ratio than calves immunized with pBISIA40-tgD or pMASIA-tgD, which has no CpG motifs inserted. Antigen-specific lymphocyte proliferation and IFN-γ secretion by peripheral blood mononuclear cells correlated positively with the CpG content of the vectors. In contrast, calves that received a killed BHV-1 vaccine had an IgG1-predominant isotype and low lymphocyte proliferation and IFN-γ levels. Following challenge, the pBISIA88-tgD-immunized group developed the greatest anamnestic response, the highest BHV-1 neutralization titres in serum and a significantly lower level of virus shedding than the saline control group. However, there were no significant differences in clinical symptoms of infection between the DNA-immunized groups and the saline control group. These data indicate that CpG-enhanced plasmids induce augmented immune responses and could be used to vaccinate against pathogens requiring a strong cellular response for protection.", }