In order to improve the accuracy for quantitating the bovine foamy virus (BFV) in vitro,we developed a baby hamster kidney cell (BHK)-21-derived indicator cell line containing a plasmid that encodes the firefly lucife...In order to improve the accuracy for quantitating the bovine foamy virus (BFV) in vitro,we developed a baby hamster kidney cell (BHK)-21-derived indicator cell line containing a plasmid that encodes the firefly luciferase driven by the BFV long terminal repeat promoter (LTR,from-7 to 1012).The BFV titer could be determined by detecting the luciferase expression since the viral trans-activator BTas protein activates the promoter activity of the LTR.One clone,designated BFVL,was selected from ten neomycin-resistant clones.BFVL showed a specific and inducible dose-and time-dependent luciferase activity in response to BFV infection.Although the changes in luciferase activity of BFVL peaked at 84 h post infection,it was possible to differentiate infected and uninfected cells at 48 h post infection.A linear relationship was established between the multiplicity of infection (MOI) of BFV and the activated ratio of luciferase expression in BFVL.Moreover,the sensitivity of the BFVL-based assay for detecting infectious BFV was 10,000 times higher than the conventional CPE-based assay at 48 h post infection.These findings suggest that the BFVL-based assay is rapid,easy,sensitive,quantitative and specific for detection of BFV infection.展开更多
基金National Natural Science Foundation of China(31070135,81071343)
文摘In order to improve the accuracy for quantitating the bovine foamy virus (BFV) in vitro,we developed a baby hamster kidney cell (BHK)-21-derived indicator cell line containing a plasmid that encodes the firefly luciferase driven by the BFV long terminal repeat promoter (LTR,from-7 to 1012).The BFV titer could be determined by detecting the luciferase expression since the viral trans-activator BTas protein activates the promoter activity of the LTR.One clone,designated BFVL,was selected from ten neomycin-resistant clones.BFVL showed a specific and inducible dose-and time-dependent luciferase activity in response to BFV infection.Although the changes in luciferase activity of BFVL peaked at 84 h post infection,it was possible to differentiate infected and uninfected cells at 48 h post infection.A linear relationship was established between the multiplicity of infection (MOI) of BFV and the activated ratio of luciferase expression in BFVL.Moreover,the sensitivity of the BFVL-based assay for detecting infectious BFV was 10,000 times higher than the conventional CPE-based assay at 48 h post infection.These findings suggest that the BFVL-based assay is rapid,easy,sensitive,quantitative and specific for detection of BFV infection.
