Bovine leukemia virus (BLV) envelope glycoprotein (gp51/ gp30(T-)), consisting of BLV gp51 and BLV gp30 that lacked its C-terminal transmembrane domain, was expressed in insect cells under the control of the baculovirus polyhedron promoter. Recombinant BLV gp51/gp30(T-) secreted from insect cells was determined by immunofluorescence, enzyme-linked immunosorbent and western blot assays using a B...

Bovine leukemia virus (BLV) is a retrovirus responsible for lymphoproliferative disorders in cattle. Although infections of BLV in animals are well known, little is known about its capacity to infect humans. This study investigated the presence of anti-BLV antibodies and BLV proviruses in human and cattle samples. An indirect enzyme-linked immunosorbent assay (ELISA) was used to detect anti-BLV...

In a previous study, we identified an interesting mutant form of the Tax protein of bovine leukemia virus (BLV), designated D247G. This mutant protein strongly transactivated the long terminal repeat of BLV and was also able to transactivate the cellular proto-oncogene c-fos. This finding suggested that BLV that encode the mutant protein might propagate and induce lymphoma more efficiently than...

The in vitro expression of bovine leukemia virus (BLV) in short-term cultured bovine peripheral blood mononuclear cells (PBMC) is associated with increased spontaneous lymphocyte blastogenesis. The purpose of this study was to determine whether intracellular pathways responsible for antigen- or mitogen-induced lymphocyte blastogenesis were also responsible for induction of BLV expression. The p...

Several sheep fetuses were thymectomized, and their tails were removed at 58 to 65 days of gestation for tissue culture. Bovine leukemia virus (BLV) antigens were detected in serial culture of tissues from fetuses whose dams and sires were both BLV positive. However, no BLV antigens were detected in serial cultures of tissues from fetuses whose dams were negative but whose sire was positive. Pr...

Bovine leukemia virus (BLV) is a retrovirus that is highly prevalent in US dairy herds: over 83% are BLV infected and the within-herd infection rate can be almost 50% on average. While BLV is known to cause lymphosarcomas, only 5% or fewer infected cattle will develop lymphoma; this low prevalence of cancer has historically not been a concern to dairy producers. However, more recent research ha...

We examined whether Bovine leukemia virus (BLV) was transmitted by rectal palpation using a common sleeve between a BLV-infected cow and BLV-negative steers. Three of four steers developed antibodies against BLV as determined by agar-gel immunodiffusion (AGID) test between 7 to 10 weeks after the first rectal palpation using common sleeves from BLV-infected cow. In the steers, BLV proviral DNA ...

Enzootic bovine leukosis (EBL) is a chronic lymphosarcoma disease of cattle caused by bovine leukemia virus (BLV). No information is available concerning the epidemiology of BLV infection in yaks (Bos mutus). One thousand five hundred and eighty-four serum samples from 610 black yaks and 974 white yaks from Gansu province, northwest China, were collected between April 2013 and March 2014 and te...

Bovine leukemia virus (BLV), one of the most common infectious viruses of cattle, is endemic in many herds. Approximately 30-40% of adult cows in the United States are infected by this oncogenic C-type retrovirus and 1-5% of animals will eventually develop a malignant lymphoma. BLV, like the human and simian T cell leukemia viruses, is a deltaretrovirus but, in contrast with the latter, the BLV...

Experimental bovine immunodeficiency-like virus (BIV)-infection and mixed infection of BIV and bovine leukemia virus (BLV) were performed on sheep. BIV proviral DNA and anti-BIV antibodies were persistently detected in all BIV-inoculated sheep. A slight increase in lymphocyte counts was observed in BIV-infected sheep, but the percentages of CD4+ and CD8+ cells in sheep peripheral blood mononucl...