RESUMO
A panel of monoclonal antibodies was prepared by immunization of BALB/c mice with Moredun (BD) virus strains. These antibodies were characterized by immunofluorescence and seroneutralization against BD, BVD and hog cholera (HC) virus strains, and radioimmunoprecipitation of BVD-infected cells extracts. The MAbs reacting with the majority of the Pestivirus strains recognize the 80 kDa antigen of the BVD cytophathic strains. The 80 kDa antigen of the BVD/Osloss virus strain has been cloned and expressed in E. coli as a fusion protein with beta-galactosidase. The fusion protein has been purified from inclusion bodies and used successfully as an antigen for ELISA detection of BVDV specific antibodies in bovine sera. A competitive ELISA using MAbs is more specific than a direct assay. These results compare well with the ones obtained with antigen extracted from BVDV-infected cells.
Assuntos
Anticorpos Monoclonais/imunologia , Anticorpos Antivirais/análise , Antígenos Virais/imunologia , Vírus da Diarreia Viral Bovina/imunologia , Pestivirus/imunologia , Animais , Especificidade de Anticorpos , Ligação Competitiva , Bovinos , Ensaio de Imunoadsorção Enzimática , Imunofluorescência , Hibridomas , Camundongos , Camundongos Endogâmicos BALB C , Testes de Neutralização , Ensaio de Radioimunoprecipitação , Proteínas Recombinantes/imunologiaRESUMO
Monoclonal antibodies have been produced against the 81/36F strain of rotavirus. One of them, was chosen as diagnostic reagent: it showed high ELISA reactivity with all the bovine, human and porcine rotavirus strains tested and reacted with VP6, structural protein product known to support the common rotavirus antigen. A sandwich ELISA procedure using the chosen monoclonal as "capture and detecting" antibody was performed to detect rotavirus in faecal samples from experimentally inoculated newborn calves: it always gave a negative response with meconium and a positive response for the stool specimens which rotavirus have been isolated. This assay was compared with Enzygnost and Slidex Rota Kit tests and with a non-commercial sandwich ELISA test using polyclonal antibodies: it showed more sensitivity than the agglutination test and was as sensitive as the other two tests to detect rotavirus in routine diagnostic material. The test evaluated showed no equivocal results.
