title: JC virus-iLOV fluorescent strains enable the detection of early and late viral protein expression.
abstract: JC virus (JCV) is highly prevalent in humans, and may cause progressive multifocal leukoencephalopathy (PML), JCV granule cell neuronopathy (JCV GCN), JCV encephalopathy (JCVE) and JCV meningitis (JCVM) in immunocompromised individuals. There is no treatment for JCV, and a growing number of multiple sclerosis patients treated with immunomodulatory medications have developed PML. Antiviral agents against JCV are therefore highly desirable but remain elusive, due to the difficulty of determining their effect in vitro. A JCV strain carrying a fluorescent protein gene would greatly simplify and accelerate the drug screening process. To achieve this goal, we selected the 366bp improved Light, Oxygen or Voltage-sensing domain (iLOV) of plant phototropin gene and created two full-length JCV-iLOV constructs on the prototype JCV Mad1 backbone. The iLOV gene was inserted either before the early regulatory T gene (iLOV-T), or after the late Agno gene (iLOV-Agno). Both JCV iLOV strains were replication-competent in vitro and emitted a fluorescent signal detectable by confocal microscope, but JCV iLOV-T exhibited higher cellular and supernatant viral loads compared to JCV iLOV-Agno. JCV iLOV-T could also produce infectious pseudovirions. These data suggest that JCV iLOV constructs may become valuable tools for anti-JCV drug screening.
authors.affiliation: Division of Neuro-Immunology, Department of Neurology; Center for Virology and Vaccine Research.
authors.forename: Xin
authors.initials: X
authors.lastname: Dang
authors.affiliation: Division of Neuro-Immunology, Department of Neurology; Center for Virology and Vaccine Research; Division of Infectious Diseases, Department of Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, United States.
authors.forename: Spyridon
authors.initials: S
authors.lastname: Chalkias
authors.affiliation: Division of Neuro-Immunology, Department of Neurology; Center for Virology and Vaccine Research. Electronic address: ikoralni@bidmc.harvard.edu.
authors.forename: Igor J
authors.initials: IJ
authors.lastname: Koralnik
mesh_terms: D000998:Antiviral Agents / Q000302:isolation & purification; D002460:Cell Line; D004353:Drug Evaluation, Preclinical / Q000379:methods; D017930:Genes, Reporter; D006801:Humans; D007577:JC Virus / Q000235:genetics / Q000502:physiology*; D008164:Luminescent Proteins / Q000032:analysis* / Q000235:genetics; D011995:Recombination, Genetic; D014764:Viral Proteins / Q000096:biosynthesis* / Q000235:genetics
chemical_list: D000998:Antiviral Agents; D008164:Luminescent Proteins; D014764:Viral Proteins
keywords: Drug screening; JC virus; PML; Therapy; iLOV