title: A new competitive ELISA detects West Nile virus infection using monoclonal antibodies against the precursor-membrane protein of West Nile virus.
abstract: Precursor membrane protein (prM) is found in the envelope of immature West Nile virus (WNV) particles. Anti-prM antibodies are found in flavivirus-infected animal sera, and they are known as relatively virus species specific antibodies. However, there are no known reports of WNV-specific epitope blocking or competitive enzyme-linked immunosorbent assay (c-ELISA) that detect anti-prM antibodies. Two anti-WNV-prM monoclonal antibodies (SHW-29C2 and SHW-31B2) were generated, and c-ELISAs were developed using these monoclonal antibodies. The c-ELISAs were evaluated using WNV-infected chicken sera. Both c-ELISAs detected anti-prM antibodies in WNV-infected chicken sera and showed little cross-reactivity to antisera against Japanese encephalitis virus, St. Louis encephalitis virus, and Murray valley encephalitis virus. The average inhibition of chicken sera at 3 weeks post WNV infection was 61.6% in SHW-29C2-based c-ELISA and 71.8% in SHW-31B2-based c-ELISA. High correlation was seen between percent inhibition in the c-ELISAs and optical density values of an IgG indirect ELISA. Additionally, SHW-31B2-based c-ELISA detected antibodies against a wide variety of WNV strains. Detecting anti-PrM antibodies using c-ELISA could be useful for WNV serodiagnosis.
authors.affiliation: Center for Animal Disease and Prevention, National Institute of Animal Health, National Agriculture and Food Research Organization, 3-1-5 Kannondai, Tsukuba, Ibaraki 305-0856, Japan.
authors.forename: Jiro
authors.initials: J
authors.lastname: Hirota
authors.forename: Shinya
authors.initials: S
authors.lastname: Shimizu
mesh_terms: D000818:Animals; D000911:Antibodies, Monoclonal; D000914:Antibodies, Viral / Q000097:blood*; D002645:Chickens; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods; D011201:Poultry Diseases / Q000175:diagnosis*; D012698:Serologic Tests / Q000379:methods; D014730:Veterinary Medicine / Q000379:methods*; D014773:Virology / Q000379:methods*; D014901:West Nile Fever / Q000175:diagnosis / Q000662:veterinary*; D014902:West Nile virus / Q000276:immunology*
chemical_list: D000911:Antibodies, Monoclonal; D000914:Antibodies, Viral