has role protective antigen role protective antigen Bovine Leukemia virus protein Tax 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. Results 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 [PubMed: 14665749]. protein Allen Xiang Oliver He Protegen ID: 410; NCBI Gene GI: 2760848; NCBI Protein GI: 9626228; NCBI Protein Accession: NP_056895; NCBITaxon: 11901