title: Development and validation of an immunohistochemistry procedure for the detection of a neurotropic bovine astrovirus.
abstract: Members of the Astroviridae family are best known to cause diarrhea in different mammalian species. Lately, some strains have been associated with encephalitis in humans, minks and cattle. In this study, we developed an immunohistochemistry (IHC) procedure for the detection of a neurotropic bovine astrovirus (BoAstV-CH13/NeuroS1), which is associated with non-suppurative encephalitis in cattle. We expressed five recombinant antigens corresponding to different putative viral proteins of BoAstV-CH13/NeuroS1. Antigens were then used for the production of hyperimmune sera in rabbits. Out of the five hyperimmune sera, the one directed against the conserved N-terminus of the viral capsid protein, termed ORF2-con, clearly surpassed the others in the detection of viral antigens in IHC in terms of strong signal intensity and low background staining. The accuracy of the ORF2-con IHC protocol was then evaluated using different sets of brain tissue samples: 30 samples from 9 animals with confirmed BoAstV-CH13/NeuroS1 infection, 30 samples from 8 animals with non-suppurative encephalitis of another etiology and 30 samples from apparently healthy slaughtered animals. The IHC was positive only with tissue samples from animals with a known positive BoAstV-CH13/NeuroS1 status, but not with those from negative ones, indicating a good diagnostic sensitivity and specificity of the assay. The ORF2-con IHC procedure is therefore an adequate tool for the detection of BoAstV-CH13/NeuroS1 infections in cattle.
authors.affiliation: NeuroCenter, Division of Neurological Sciences, Vetsuisse Faculty, University of Bern, Bremgartenstrasse 109A, CH-3012, Bern, Switzerland. Electronic address: celine.boujon@vetsuisse.unibe.ch.
authors.forename: Céline L
authors.initials: CL
authors.lastname: Boujon
authors.affiliation: NeuroCenter, Division of Neurological Sciences, Vetsuisse Faculty, University of Bern, Bremgartenstrasse 109A, CH-3012, Bern, Switzerland; Graduate School for Cellular and Biomedical Sciences, University of Bern, Freiestrasse 1, CH-3012, Bern, Switzerland. Electronic address: senija.selimovic@vetsuisse.unibe.ch.
authors.forename: Senija
authors.initials: S
authors.lastname: Selimovic-Hamza
authors.affiliation: NeuroCenter, Division of Neurological Sciences, Vetsuisse Faculty, University of Bern, Bremgartenstrasse 109A, CH-3012, Bern, Switzerland. Electronic address: ilias.bouzalas@vetsuisse.unibe.ch.
authors.forename: Ilias
authors.initials: I
authors.lastname: Bouzalas
authors.affiliation: NeuroCenter, Division of Neurological Sciences, Vetsuisse Faculty, University of Bern, Bremgartenstrasse 109A, CH-3012, Bern, Switzerland. Electronic address: torsten.seuberlich@vetsuisse.unibe.ch.
authors.forename: Torsten
authors.initials: T
authors.lastname: Seuberlich
mesh_terms: D000818:Animals; D000956:Antigens, Viral / Q000032:analysis* / Q000276:immunology; D019350:Astroviridae Infections / Q000175:diagnosis / Q000276:immunology / Q000662:veterinary* / Q000821:virology; D036022:Capsid Proteins / Q000276:immunology; D002417:Cattle; D002418:Cattle Diseases / Q000175:diagnosis* / Q000276:immunology / Q000821:virology; D018792:Encephalitis, Viral / Q000662:veterinary* / Q000821:virology; D007150:Immunohistochemistry / Q000379:methods*; D001257:Mamastrovirus / Q000235:genetics / Q000276:immunology* / Q000302:isolation & purification*; D012680:Sensitivity and Specificity
chemical_list: D000956:Antigens, Viral; D036022:Capsid Proteins
keywords: Astrovirus; Cattle; Encephalitis; Immunohistochemistry