Biologische Sicherheitsforschung. Teilprojekt 2: Pseudorabiesvirus Abschlussbericht

Available from TIB Hannover: DtF QN1(45,49) / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekSIGLEBundesministerium fuer Bildung, Wissenschaft, Forschung und Technologie, Bonn (Germany)DEGerman

Effects of hypervaccination with bovine herpesvirus type 1 gE-deleted marker vaccines on the serological response and virological status of calves challenged with wild-type virus.

&lt;p&gt;Twenty-four calves were immunised four times with gE-deleted infectious bovine rhinotracheitis marker vaccines before being challenged with small doses of wild-type bovine herpesvirus type 1 (BHV-1). The repeated vaccinations induced strong immunity that prevented detectable virus replication and gE-seroconversion after the challenge infection in most of the calves. The hypervaccinated calves that shed virus after the challenge infection showed no delay in gE-seroconversion compared with unvaccinated control calves. Using a sensitive nested PCR, BHV-1 gE sequences could be detected in the trigeminal ganglia of several of the gE-seronegative, challenge-infected calves, possibly indicating the presence of wild-type BHV-1 DNA.&lt;/p&gt;</p

Comparison of different prime-boost regimes with DNA and recombinant Orf virus based vaccines expressing glycoprotein D of pseudorabies virus in pigs

Both DNA and Orf virus (ORFV; Parapox virus) based vaccines have shown promise as alternatives for conventional vaccines in pigs against pseudorabies virus (PRV) infection causing Aujeszky's disease. In the present study we evaluated the efficacy of different prime-boost regimes in pigs in terms of immunogenicity and protection against challenge infection with PRV. The different prime-boost regimes consisted of the homologous prime-boost regimes (DNA followed by DNA or ORFV followed by ORFV) and the heterologous prime-boost regimes (DNA followed by ORFV and ORFV followed by DNA), all based on glycoprotein D (gD) of PRV. Moreover, we compared the efficacy of the different prime-boost regimes with the efficacy of a conventional modified live vaccine (MLV). The different prime-boost regimes resulted in different levels of immunity and protection against challenge infection. Most effective was the regime of priming with DNA vaccine followed by boosting with the ORFV based vaccine. This regime resulted in strong antibody responses, comparable to the antibody responses obtained after prime-boost vaccination with a conventional MLV vaccine. Also with regard to protection, the prime DNA-boost ORFV regime performed better than the other prime-boost regimes. This study demonstrates the potential of a heterologous prime-boost vaccination strategy against PRV based on a single antigen, and that in the natural host, the pig

Comparison of different prime-boost regimes with DNA and recombinant Orf virus based vaccines expressing glycoprotein D of pseudorabies virus in pigs

Both DNA and Orf virus (ORFV; Parapox virus) based vaccines have shown promise as alternatives for conventional vaccines in pigs against pseudorabies virus (PRV) infection causing Aujeszky's disease. In the present study we evaluated the efficacy of different prime-boost regimes in pigs in terms of immunogenicity and protection against challenge infection with PRV. The different prime-boost regimes consisted of the homologous prime-boost regimes (DNA followed by DNA or ORFV followed by ORFV) and the heterologous prime-boost regimes (DNA followed by ORFV and ORFV followed by DNA), all based on glycoprotein D (gD) of PRV. Moreover, we compared the efficacy of the different prime-boost regimes with the efficacy of a conventional modified live vaccine (MLV). The different prime-boost regimes resulted in different levels of immunity and protection against challenge infection. Most effective was the regime of priming with DNA vaccine followed by boosting with the ORFV based vaccine. This regime resulted in strong antibody responses, comparable to the antibody responses obtained after prime-boost vaccination with a conventional MLV vaccine. Also with regard to protection, the prime DNA-boost ORFV regime performed better than the other prime-boost regimes. This study demonstrates the potential of a heterologous prime-boost vaccination strategy against PRV based on a single antigen, and that in the natural host, the pig

Appearance of the bona fide spiral tubule of ORF virus is dependent on an intact 10-kilodalton viral protein.

Parapoxviruses can be morphologically distinguished from other poxviruses in conventional negative staining electron microscopy (EM) by their ovoid appearance and the spiral tubule surrounding the virion's surface. However, this technique may introduce artifacts. We have examined Orf virus (ORFV; the prototype species of the Parapoxvirus genus) by cryoelectron microscopy (cryo-EM) and cryo-negative staining EM. From these studies we suggest that the shape and unique spiral tubule are authentic features of the parapoxviruses. We also constructed an ORFV mutant deleted of a gene encoding a 10-kDa protein, which is an orthologue of the vaccinia virus (VACV) 14-kDa fusion protein, and investigated its ultrastructure. This mutant virus multiplied slowly in permissive cells and produced infectious but morphologically aberrant particles. Mutant virions lacked the spiral tubule but displayed short disorganized tubules similar to those observed on the surface of VACV. In addition, thin extensions or loop-like structures were appended to the ORFV mutant particles. We suggest that these appended structures arise from a failure of the mutant virus particles to properly seal and that the sealing activity is dependent on the 10-kDa protein

Development of DNA probe for detection of Aujeszky's disease virus Desenvolvimento de uma sonda de DNA para a detecção do vírus da doença de Aujeszky

A DNA hybridization dot-blot assay using a radioactive and a non-radioactive probe has been developed for the detection of Aujeszky's disease virus (ADV). The Bam H I 7 fragment of ADV genomic DNA was labeled by nick translation using 32P-dCTP and the 196bp polymerase chain reaction (PCR) gG glycoprotein gene amplified fragment was also labeled by nick translation but using biotin d-7-dATP. This technique provides a fast and effective means of detecting acute cases of ADV infection but it was unable to detect ADV nucleic acid sequences in trigeminal nerve ganglia of latent infected pigs and mice.<br>Uma sonda radioativa e uma outra biotinilada foram produzidas para detecção do vírus da doença de Aujeszky (VDA). O fragmento de Bam H I 7 do DNA genômico do VDA foi marcado por "nick translation" empregando P32dCTP e um fragmento de 196pb, resultante de uma amplificação pela reação em cadeia pela polimerase marcado com biotina 7-dATP. Essas sondas, de uma maneira rápida e específica, prestaram-se para a detecção da infecção aguda pelo VDA. Entretanto, não se mostraram sensíveis o suficiente para detectar seqüências genômicas de VDA no gânglio trigêmio de suínos e camundongos com infecção latente