Clicky

Intraspecific bovine herpesvirus 1 recombinants carrying glycoprotein E deletion as a vaccine marker are virulent

Vaccination against BHV-1 is widely practiced. Possession of the animal should be legal per state community and other applicable laws. Major hurdles to the development of DNA vaccines for herpesviruses in general and for BoHV-1 in particular are that both cell-mediated and humoral responses are required (14) and humoral responses need to be increased over those that can be obtained with naked DNA (15). A major hurdle to DNA vaccination is the small number of cells that are transfected, but this may be overcome in part by utilizing the intercellular trafficking capacity of VP22 to disseminate the expressed antigen to neighboring cells, thus increasing antigen presentation. This same scenario may also occur in cattle at pasture, although outbreaks of disease are sporadic in pastured cattle and generally only associated with stressful situations like weaning, extremely dusty conditions or particularly inclement weather. Major hurdles to the development of DNA vaccines for herpesviruses in general and for BoHV-1 in particular are that both cell-mediated and humoral responses are required (14) and humoral responses need to be increased over those that can be obtained with naked DNA (15). Furthermore, BHV-1 has been associated with meningo-encephalitic diseases, infectious balanoposthitis, and may predispose cattle to secondary opportunistic bacterial infections (37, 41).

Preliminary results indicate that both genes are transcribed and expressed when transfected into bovine (MDBK) cells. For subscription information, contact asp@allenpress.com. Full text Full text is available as a scanned copy of the original print version. Links to PubMed are also available for Selected References. To assess the efficacy, two goats were inoculated intranasally twice 2 weeks apart with a gE-negative BoHV-1 vaccine. Furthermore, conventional inactivated and attenuated vaccines are less efficacious in neonates, so alternative vaccine types such as CpG adjuvanted protein vaccines or DNA vaccines are required for effective vaccination of this age group. The consequences of this process, related to herpesvirus evolution, have to be assessed in the context of large use of live marker vaccines based on glycoprotein E (gE) gene deletion.

The use of the IBRV(NG)dltkdlgIII strain in conjunction with an anti-gIII specific blocking ELISA kit represents a powerful tool for BHV-1 control/eradication programs. injection of cattle. The many vaccines reported include replicating and non-replicating, conventional and genetically engineered, as well as marker and non-marker preparations. Results suggest that this combination vaccine provided protection from infection with virulent BHV-1 and significantly reduced nasal shedding of the virus for at least 126 days after vaccination. This recombinant will be further evaluated as a candidate virus for a BHV1 differential vaccine. Get a printable copy (PDF file) of the complete article (860K), or click on a page image below to browse page by page. Rectal temperatures were lower (P < 0.05) during days 4-8 for each of the VAC groups as compared to combined CON groups. After corticosteroid treatments, re-excretion of virus was never detected in cattle that had been inoculated with the gE-negative BHV1 vaccine strain. This is the first report of the use of VP22 as a transport molecule in the context of a DNA vaccine for a large animal species. Only the calves given the pVAX-tgD co-immunised with pVAX-48CpG (Vaccine B) developed humoral antibodies against BoHV-1 between 56 and 90 days after the first vaccination, whereas in calves of other groups and in the controls, antibodies appeared only after the infection. Unlike vaccinated calves, clinical reaction to challenge in both unvaccinated groups also involved nasal discharge but the duration of both the nasal discharge and the severe pyrexia was significantly shorter in unvaccinated passively immune calves. The non-vaccinated calves shed significantly (P < 0.05) more virus than all other groups on days 4, 8 and 10 post challenge. In the same period, 21 per cent of the unvaccinated control cattle also seroconverted, suggesting that the vaccine virus had been transmitted to them. Thirty months after they had been vaccinated 91 per cent of the vaccinated animals which responded still had detectable antibodies. The safety and immunogenicity of the recombinant BHV1 virus 39B1 were similar to those reported for other registered BHV1 vaccines and the virus would appear to be suitable for the production of a vaccine seed lot and more exhaustive field trials as a prelude to commercial vaccine production and registration. The herd-level seroprevalence of BoHV-1 and BVDV in Northern Ireland was estimated in non-vaccinating herds and associations between possible risk factors (herd type and herd size (quartiles)) and herd-level prevalence were determined using chi-squared analysis. or i.n., as well as the controls, antibody first appeared in their sera 14 days post-challenge infection. Vaccine Immune Response Type: VO_0000286 Efficacy: Following challenge with BHV-1, calves immunized with the recombinant NDVs had lower titers and earlier clearance of challenge virus compared to the empty vector control, and reduced disease was observed with rLaSota/gDFL. Your library or institution may give you access to the complete full text for this document in ProQuest.