Complement-dependent cytotoxicity assay for differentiating West Nile virus from Japanese encephalitis virus infections in horses.
A complement-dependent cytotoxicity (CDC) assay was established to measure antibodies to the West Nile virus (WNV) nonstructural protein 1 (NS1) in horses. Sera collected from a WNV-infected horse mediated lysis of WNV NS1-expressing cells in a dose-dependent manner at higher percentages than sera from a Japanese encephalitis virus (JEV)-infected horse. The percentages of specific lysis for sera diluted 1:10 to 1:80 were <19.8% (assay cutoff) for almost all of the 100 JEV-infected or uninfected horses tested, in contrast to 55 to 76% in WNV-infected horses. Experimental infection revealed that horses became anti-WNV NS1 antibody positive 10 days after WNV infection. This study demonstrated the utility of this assay for differentiating WNV from JEV infections in horses.
Kitai
Yoko
Y
Department of International Health, Kobe University Graduate School of Health Sciences, Kobe, Japan.
Kondo
Takashi
T
Konishi
Eiji
E
D000818:Animals; D000914:Antibodies, Viral / Q000097:blood*; D003165:Complement System Proteins / Q000276:immunology*; D003601:Cytotoxicity Tests, Immunologic / Q000379:methods*; D003937:Diagnosis, Differential; D004664:Encephalitis Virus, Japanese / Q000276:immunology; D004672:Encephalitis, Japanese / Q000175:diagnosis / Q000662:veterinary*; D006734:Horse Diseases / Q000175:diagnosis* / Q000821:virology; D006736:Horses; D012680:Sensitivity and Specificity; D014901:West Nile Fever / Q000175:diagnosis / Q000662:veterinary*; D014902:West Nile virus / Q000276:immunology
D000914:Antibodies, Viral; D003165:Complement System Proteins