RESUMO
Major immunogenic sites of foot-and-mouth disease virus (FMDV) have been mapped to the C-terminal third of capsid protein VP1; we studied the immunogenicity of a series of TrpE-FMDV fusion proteins containing this region of FMDV strain O1 Campos. Fusion protein TrpE-dCN, which contains a dimer of VP1 amino acid sequences consisting of amino acids 200 to 213 linked by a diproline spacer to amino acids 141 to 158 (200-213 approximately P-P-G approximately 141-158), induced the best response. A single inoculation of guinea-pigs with 100 micrograms TrpE-dCN elicited high levels of neutralizing antibodies and protected all the animals against challenge infection with homologous virus. Although the closely related FMDV strains O1 Campos and O1 Caseros induced high levels of cross-protection, TrpE-dCN-vaccinated guinea-pigs were poorly protected against challenge infection with heterologous FMDV strain O1 Caseros. Nucleotide sequence analysis revealed that amino acid differences at residues 149 and 152 were critical for the induction of cross-protection and that neutralizing epitopes not present in TrpE-dCN are likely to be responsible for conferring a high level of cross-protection between FMDV strains O1 Campos and O1 Caseros.
Assuntos
Aphthovirus/imunologia , Capsídeo/imunologia , Proteínas Virais de Fusão/imunologia , Sequência de Aminoácidos , Animais , Antígenos Virais/imunologia , Aphthovirus/genética , Capsídeo/análise , Capsídeo/genética , Proteínas do Capsídeo , Reações Cruzadas , Ensaio de Imunoadsorção Enzimática , Febre Aftosa/imunologia , Cobaias , Substâncias Macromoleculares , Dados de Sequência Molecular , Testes de Neutralização , Proteínas Recombinantes de Fusão/análise , Proteínas Recombinantes de Fusão/imunologia , Vacinação , Proteínas Virais de Fusão/genéticaRESUMO
The nucleotide sequences of the VP1-coding regions of several isolates of serotype C3 foot-and-mouth disease virus (FMDV) were determined. The deduced amino acid sequences were compared with those of serotype C1 FMDV. The results provide evidence for two different lineages of FMDV C3 and document the potential for both long-term conservation and rapid evolution of FMDV.
Assuntos
Aphthovirus/genética , Capsídeo/genética , Genes Virais , RNA Viral/genética , Sequência de Aminoácidos , Animais , Aphthovirus/classificação , Sequência de Bases , Bovinos , Linhagem Celular , Células Cultivadas , Dados de Sequência Molecular , MutaçãoRESUMO
cDNA libraries, representative of potato viruses X (PVXc strain) and Y (PVY degrees strain) genomes were obtained. A PVX cDNA cloned fragment was sequenced and biotinylated to be used as hybridization probe for the detection of purified virus or nucleic acid extracts of infected plants. Dot hybridization assay was sensitive to detect 4 ng of viral particles, corresponding to about 200 pg of viral RNA. The level of detection in infected plant extracts was as effective as that obtained with the ELISA. The presence of biotinylated PVY cDNA in the hybridization mixture did not affect sensitivity of the PVX detection assay, suggesting that a single diagnostic assay for several potato viruses and virus-related pathogens could be developed.