title: Characterization of in vitro dengue virus resistance to carrageenan.
abstract: The λ-carrageenan (λ-car) is a potent and selective inhibitor of dengue virus (DENV) infection targeted to virus adsorption and internalization, due to the structural similarities with the mammalian cell receptor heparan sulfate. To further characterize the antiviral activity of λ-car, the selection and the phenotypic and genomic features of λ-car resistant DENV-2 variants are studied here in comparison to control virus. Resistant variants were rapidly selected in Vero cells after three passages in presence of the drug. No difference was detected in the growth profiles in Vero and C6/36 cells between resistant and control viruses. By contrast, the kinetics of adsorption and internalization of resistant variants in Vero cells was significantly diminished whereas entry to C6/36 cells was unaffected. By plaque purification and sequence analysis of the population, two types of resistant clones were found: some clones presented two mutations in E protein, K126E, and F422L; but other equally λ-car resistant clones had no mutations in E. Furthermore, no mutations were found in other viral proteins like prM, C, or NS1. The genomic disparity in E protein was also associated to differences in phenotype stability. The stable genomic resistance here described provides information about determinants in E protein involved in receptor binding and membrane fusion for uncoating.
authors.affiliation: Laboratory of Virology, Faculty of Sciences, Department of Biological Chemistry, University of Buenos Aires, Buenos Aires, Argentina.
authors.forename: Laura B
authors.initials: LB
authors.lastname: Talarico
authors.affiliation: Laboratory of Virology, Faculty of Sciences, Department of Biological Chemistry, University of Buenos Aires, Buenos Aires, Argentina.|IQUIBICEN-National Research Council (CONICET), Ciudad Universitaria, Buenos Aires, Argentina.
authors.forename: Elsa B
authors.initials: EB
authors.lastname: Damonte
mesh_terms: D000818:Animals; D000998:Antiviral Agents / Q000494:pharmacology; D002351:Carrageenan / Q000494:pharmacology*; D002460:Cell Line; D002522:Chlorocebus aethiops; D003716:Dengue Virus / Q000187:drug effects* / Q000235:genetics* / Q000502:physiology; D024882:Drug Resistance, Viral / Q000235:genetics*; D016679:Genome, Viral; D005838:Genotype; D009154:Mutation; D010641:Phenotype; D014709:Vero Cells; D014759:Viral Envelope Proteins / Q000235:genetics; D017361:Viral Nonstructural Proteins / Q000235:genetics; D014764:Viral Proteins / Q000235:genetics; D014779:Virus Replication / Q000187:drug effects
chemical_list: D000998:Antiviral Agents; C079340:NS1 protein, Dengue virus type 2; D014759:Viral Envelope Proteins; D017361:Viral Nonstructural Proteins; D014764:Viral Proteins; C072281:E protein TH Sman, Dengue virus; D002351:Carrageenan
keywords: antiviral resistance; carrageenans; dengue virus; sulfated polysaccharides; virus entry