title: Serodiagnosis of equine infectious anemia by agar gel immunodiffusion and ELISA using a recombinant p26 viral protein expressed in Escherichia coli as antigen.
abstract: We used a p26 recombinant protein (p26r) from equine infectious-anemia virus (EIAV) expressed in Escherichia coli as antigen to standardize an agar-gel immunodiffusion (AGIDp26r) test and an indirect ELISA (ELISAp26r) for the detection of antibodies against EIAV in 720 equine sera from Brazil. We evaluated the tests's relative diagnostic sensitivities (relSe) and relative diagnostic specificities (relSp) against a commercial AGID kit (Idexx, USA). We used three sera panels: panel A--196 AGID-negative sera from an AIE non-endemic controlled area; panel B--194 AGID-negative sera from an AIE endemic area and panel C--330 AGID-positive sera from an AIE endemic area. ELISAp26r cut-off value was defined with TG-ROC using sera from panels A and C. AGIDp26r showed an agreement of 100% with the commercial kit. When applied to sera from panels A and C, ELISAp26r showed an agreement of 100% with the kit, but, although relSe was 100% for panel C, the ELISAp26r had relSp of 93.3%.
authors.affiliation: Department of Preventive Veterinary Medicine and Animal Health, School of Veterinary Medicine, University of São Paulo, CEP 05508-270, São Paulo, SP, Brazil.
authors.forename: Adriana S Toledo
authors.initials: AS
authors.lastname: Piza
authors.forename: Alessandra Rael
authors.initials: AR
authors.lastname: Pereira
authors.forename: Maria Thereza
authors.initials: MT
authors.lastname: Terreran
authors.forename: Otto
authors.initials: O
authors.lastname: Mozzer
authors.forename: Amílcar
authors.initials: A
authors.lastname: Tanuri
authors.forename: Paulo Eduardo
authors.initials: PE
authors.lastname: Brandão
authors.forename: Leonardo José
authors.initials: LJ
authors.lastname: Richtzenhain
mesh_terms: D000818:Animals; D000914:Antibodies, Viral / Q000097:blood*; D000956:Antigens, Viral / Q000276:immunology; D001938:Brazil / Q000453:epidemiology; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods / Q000592:standards / Q000662:veterinary*; D004859:Equine Infectious Anemia / Q000175:diagnosis / Q000453:epidemiology*; D004926:Escherichia coli / Q000821:virology; D006736:Horses; D005779:Immunodiffusion / Q000379:methods / Q000592:standards / Q000662:veterinary*; D011933:Reagent Kits, Diagnostic / Q000592:standards / Q000662:veterinary; D012680:Sensitivity and Specificity; D016036:Seroepidemiologic Studies; D013997:Time Factors; D014758:Viral Core Proteins / Q000276:immunology*
chemical_list: D000914:Antibodies, Viral; D000956:Antigens, Viral; D011933:Reagent Kits, Diagnostic; D014758:Viral Core Proteins; C117895:equine infectious anemia virus, p26