title: A new indicator cell line to monitor human foamy virus infection and stability in vitro.
abstract: In order to determine the human foamy virus (HFV) infection in vitro conveniently, we developed a baby hamster kidney cell (BHK)-21-derived indicator cell line (BHK-HFVLTR-EGFP) containing a plasmid that encodes the enhanced green fluorescent protein (EGFP) driven by the HFV long terminal repeat promoter. The viral trans-activator Bel-1 protein can induce EGFP expression, so the HFV titer could be determined by counting the corresponding EGFP-positive cells. This foamy-virus-activated EGFP expression (FAE) assay was about 50 times more sensitive than the traditional focus plaque assay by end-point dilution. Additionally, the results of the FAE assay can be obtained rapidly within 2 days, whereas the determination of focus developing needs 2 weeks. Moreover, a linear relationship was found between the fluorescence intensity and the titer of inoculated HFV. In brief, the FAE assay is a rapid, easy, sensitive and quantitative method for monitoring and investigating HFV infection. Using the indicator cell line BHK-HFVLTR-EGFP, we examined the effects of repeated freeze-and-thaw cycles and temperature on HFV stability by the FAE assay. Such information about HFV infection and stability would be valuable for HFV applications.
authors.affiliation: Institute of Virology, College of Life Sciences, Wuhan University, Wuhan, PR China.
authors.forename: Zhi
authors.initials: Z
authors.lastname: Li
authors.forename: Ping
authors.initials: P
authors.lastname: Yang
authors.forename: Hui
authors.initials: H
authors.lastname: Liu
authors.forename: Wen-xin
authors.initials: WX
authors.lastname: Li
mesh_terms: D000818:Animals; D002460:Cell Line; D006224:Cricetinae; D005814:Genes, Viral; D005822:Genetic Vectors; D049452:Green Fluorescent Proteins; D006801:Humans; D008164:Luminescent Proteins / Q000235:genetics / Q000378:metabolism; D012680:Sensitivity and Specificity; D016092:Spumavirus / Q000235:genetics / Q000254:growth & development / Q000302:isolation & purification / Q000502:physiology*; D020079:Terminal Repeat Sequences; D015678:Viral Structural Proteins / Q000235:genetics
chemical_list: D008164:Luminescent Proteins; D015678:Viral Structural Proteins; D049452:Green Fluorescent Proteins