title: Attenuation and immunogenicity of recombinant yellow fever 17D-dengue type 2 virus for rhesus monkeys.
abstract: A chimeric yellow fever (YF)-dengue serotype 2 (dengue 2) virus was constructed by replacing the premembrane and envelope genes of the YF 17D virus with those from dengue 2 virus strains of Southeast Asian genotype. The virus grew to high titers in Vero cells and, after passage 2, was used for immunogenicity and attenuation studies in rhesus monkeys. Subcutaneous immunization of naive rhesus monkeys with the 17D-D2 chimeric virus induced a neutralizing antibody response associated with the protection of 6 of 7 monkeys against viremia by wild-type dengue 2 virus. Neutralizing antibody titers to dengue 2 were significantly lower in YF-immune animals than in YF-naive monkeys and protection against challenge with wild-type dengue 2 virus was observed in only 2 of 11 YF-immune monkeys. An anamnestic response to dengue 2, indicated by a sharp increase of neutralizing antibody titers, was observed in the majority of the monkeys after challenge with wild-type virus. Virus attenuation was demonstrated using the standard monkey neurovirulence test. The 17D-D2 chimera caused significantly fewer histological lesions than the YF 17DD virus. The attenuated phenotype could also be inferred from the limited viremias compared to the YF 17DD vaccine. Overall, these results provide further support for the use of chimeric viruses for the development of a new live tetravalent dengue vaccine.
authors.affiliation: Departamento de Bioquímica e Biologia Molecular, Instituto Oswaldo Cruz, FIOCRUZ, 21045-900 Rio de Janeiro, RJ, Brazil. rgaller@ioc.ficruz.br
authors.forename: R
authors.initials: R
authors.lastname: Galler
authors.forename: R S
authors.initials: RS
authors.lastname: Marchevsky
authors.forename: E
authors.initials: E
authors.lastname: Caride
authors.forename: L F C
authors.initials: LF
authors.lastname: Almeida
authors.forename: A M Y
authors.initials: AM
authors.lastname: Yamamura
authors.forename: A V
authors.initials: AV
authors.lastname: Jabor
authors.forename: M C A
authors.initials: MC
authors.lastname: Motta
authors.forename: M C
authors.initials: MC
authors.lastname: Bonaldo
authors.forename: E S F
authors.initials: ES
authors.lastname: Coutinho
authors.forename: M S
authors.initials: MS
authors.lastname: Freire
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D000914:Antibodies, Viral / Q000096:biosynthesis* / Q000276:immunology; D002522:Chlorocebus aethiops; D003716:Dengue Virus / Q000235:genetics / Q000276:immunology*; D005260:Female; D008253:Macaca mulatta; D008297:Male; D008969:Molecular Sequence Data; D009500:Neutralization Tests; D011995:Recombination, Genetic; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014709:Vero Cells; D014766:Viremia / Q000276:immunology*; D015005:Yellow fever virus / Q000235:genetics / Q000276:immunology*
chemical_list: D000914:Antibodies, Viral