Protective effects of vaccination with bovine leukemia virus (BLV) Tax DNA against BLV infection in sheep.
A DNA vaccination trial was performed on sheep to determine whether vaccination with bovine leukemia virus (BLV) transactivator Tax DNA is effective against BLV infection. Immunization was carried out with cationic liposomes containing the Tax-expressing plasmid DNA and subsequently all sheep were challenged with BLV. BLV titers in peripheral blood mononuclear cell (PBMC) determined by syncytium formation assay and BLV provirus load detected by genomic PCR analysis showed higher levels of virus titers in control sheep than those in Tax-vaccinated sheep. Higher levels of IFN-gamma mRNA expression have been demonstrated in vaccinated sheep after the challenge. These results suggested that Th1 type immune response induced by Tax DNA vaccine inhibited BLV propagation in vaccinated sheep at the early phase of infection.
Usui
Tatsufumi
T
Laboratory of Infectious Diseases, Department of Disease Control, Graduate School of Veterinary Medicine, Hokkaido University, Sapporo, Japan.
Konnai
Satoru
S
Tajima
Shigeru
S
Watarai
Shinobu
S
Aida
Yoko
Y
Ohashi
Kazuhiko
K
Onuma
Misao
M
D000818:Animals; D016207:Cytokines / Q000235:genetics; D017931:DNA Primers; D006800:Deltaretrovirus Infections / Q000517:prevention & control* / Q000662:veterinary*; D016356:Gene Products, tax / Q000276:immunology; D001909:Leukemia Virus, Bovine / Q000276:immunology*; D016133:Polymerase Chain Reaction; D012333:RNA, Messenger / Q000235:genetics; D012756:Sheep; D012757:Sheep Diseases / Q000276:immunology / Q000517:prevention & control* / Q000821:virology; D014611:Vaccination / Q000662:veterinary*; D019444:Vaccines, DNA / Q000276:immunology
D016207:Cytokines; D017931:DNA Primers; D016356:Gene Products, tax; D012333:RNA, Messenger; D019444:Vaccines, DNA