RESUMO
The relative merits of various in vitro assay systems for the measurement of the quality and quantity of foot-and-mouth disease virus vaccine antigen will be discussed. The assay systems include : viral infectivity, complement fixing activity, particle counts, radial diffusion titre and single radial haemolysis titre. The predictive value of the tests for the immunogenicity of the final vaccine product will be evaluated against the results of 50% Protective Dose titres determined in guinea pigs and cattle by antibody assay and by challenge.
Assuntos
Antígenos Virais/análise , Aphthovirus/imunologia , Vacinas Virais/análise , Animais , Formação de Anticorpos , Bovinos , Centrifugação com Gradiente de Concentração , Testes de Fixação de Complemento , Cobaias , Hemólise , Imunodifusão , Proteínas Virais/análise , Vacinas Virais/normasRESUMO
The presence of either thiosulphate-neutralized or free AEI was shown to degrade inactivated foot-and-mouth disease virus Type O (Hong Kong) antigen during storage at 4 degrees C. Deterioration was evident after 20 weeks of storage and little antigen remained at 36 weeks. Optimum stability was obtained by removing the residual inactivant immediately after inactivation.