gp51 of bovine leukemia virus gene expression in hamster cells.

Recombinant pMMEx-bovine leukemia virus env gene DNA fragments were produced and expressed in eukaryotic cells. Clone C4, containing an SmaI-SmaI fragment of the gene coding for gp51, was co-transfected with pSV2neo DNA into Chinese hamster cells. About 800 geneticin-resistant cell clones were isolated and then morphologically and biologically characterized. The presence of gp51 encoding env gene fragments was detected in 17 of them by Southern blotting. The expression of gp51 gene in hamster cells was confirmed by Western blotting of their lysates with monoclonal antibodies (MAbs) directed against different epitopes of gp51 of bovine leukemia virus. The immunoreactivity of the expressed peptides with MAbs directed against neutralizing epitopes of gp51 of bovine leukemia virus was confirmed.