Vero cell-derived inactivated West Nile (WN) vaccine induces protective immunity against lethal WN virus infection in mice and shows a facilitated neutralizing antibody response in mice previously immunized with Japanese encephalitis vaccine.
A novel Vero cell-derived inactivated WN vaccine (WN-VAX) was prepared from virus strain NY99-35262. Two immunizations with WN-VAX induced high levels of neutralizing antibody to WN virus. All immunized mice were protected against challenge with a lethal dose of WN virus. No WN viremia was detected, and the level of WN virus-neutralizing antibody increased rapidly. WN-VAX was then examined for immunogenicity in mice previously immunized with Japanese encephalitis vaccine (JE-VAX). Immunization with WN-VAX induced WN virus-neutralizing antibody in all mice previously immunized with JE-VAX but in only half of the control mice at 10 weeks. These results indicate that WN-VAX induced complete protective immunity against lethal WN infection and that the WN-VAX-induced antibody response is facilitated in JE-VAX-immunized mice. This WN-VAX is thus a candidate WN vaccine for humans.
Lim
Chang-Kweng
CK
Department of Virology I, National Institute of Infectious Diseases, Toyama, Shinjuku, Tokyo 162-8640, Japan. ck@nih.go.jp
Takasaki
Tomohiko
T
Kotaki
Akira
A
Kurane
Ichiro
I
D000818:Animals; D000914:Antibodies, Viral / Q000097:blood*; D002522:Chlorocebus aethiops; D005260:Female; D022321:Japanese Encephalitis Vaccines / Q000276:immunology*; D051379:Mice; D008809:Mice, Inbred C3H; D009500:Neutralization Tests; D012367:RNA, Viral / Q000097:blood; D016019:Survival Analysis; D015164:Vaccines, Inactivated / Q000276:immunology; D014709:Vero Cells; D014766:Viremia / Q000517:prevention & control; D014901:West Nile Fever / Q000517:prevention & control*; D053060:West Nile Virus Vaccines / Q000276:immunology*; D014902:West Nile virus / Q000254:growth & development* / Q000276:immunology
D000914:Antibodies, Viral; D022321:Japanese Encephalitis Vaccines; D012367:RNA, Viral; D015164:Vaccines, Inactivated; D053060:West Nile Virus Vaccines