Chimeric Langat/Dengue viruses protect mice from heterologous challenge with the highly virulent strains of tick-borne encephalitis virus.
Langat virus (LGT), a tick-borne flavivirus, is naturally attenuated for humans but it is very virulent in SCID mice. In contrast, viable recombinant chimeras of LGT (preM and E genes) and dengue type 4 virus (all other sequences) recovered in mosquito cell culture were completely attenuated in SCID mice but still capable of providing protection against LGT. To develop the chimeras into vaccine candidates, we adapted them to replicate efficiently in simian Vero cells, a satisfactory substrate for human vaccines. The adapted chimeras remained completely attenuated for SCID mice and, significantly, provided protection in immunocompetent mice against tick-borne encephalitis virus, the most virulent of the tick-borne flaviviruses.
Laboratory of Infectious Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland 20892, USA. apletnev@niaid.nih.gov
A G
AG
Pletnev
G G
GG
Karganova
T I
TI
Dzhivanyan
V A
VA
Lashkevich
M
M
Bray
D000222:Adaptation, Physiological; D000818:Animals; D002522:Chlorocebus aethiops; D003716:Dengue Virus / Q000235:genetics / Q000276:immunology*; D004669:Encephalitis Viruses, Tick-Borne / Q000235:genetics / Q000276:immunology* / Q000472:pathogenicity; D004675:Encephalitis, Tick-Borne / Q000276:immunology / Q000517:prevention & control*; D005260:Female; D005822:Genetic Vectors / Q000235:genetics / Q000276:immunology; D006801:Humans; D051379:Mice; D008807:Mice, Inbred BALB C; D016513:Mice, SCID; D014614:Vaccines, Synthetic / Q000235:genetics / Q000276:immunology*; D014709:Vero Cells; D014759:Viral Envelope Proteins / Q000235:genetics / Q000276:immunology*; D014765:Viral Vaccines / Q000235:genetics / Q000276:immunology*; D014774:Virulence
D014614:Vaccines, Synthetic; D014759:Viral Envelope Proteins; D014765:Viral Vaccines; C074932:prM protein, Flavivirus; C065696:glycoprotein E, Flavivirus