Efficacy of a gE-deleted, bovine herpesvirus 1 (BoHV-1) inactivated vaccine

Abstract

Pesq. Vet. Bras. 29(7): 545-551, julho 2009 RESUMO.-[Eficácia de uma vacina inativada, gE-deletada, contra o herpesvírus bovino tipo 1 (BoHV-1).] O Herpesvírus bovino tipo 1 (BoHV-1) é reconhecido como um importante agente de perdas econômicas em bovinos. Vacinação tem sido amplamente empregada para minimizar as perdas conseqüentes a infecções com o BoHV-1. Reportamos previamente o desenvolvimento de uma vacina diferencial para BoHV-1, baseada em um recombinante do qual a glicoproteína gE (gE) foi deletada (265gE -). No presente trabalho foi realizada a avaliação da eficácia de tal recombinante como vacina inativada. Cinco bovinos soronegativos para BoHV-1 foram vacinadas por via intramuscular no dia 0 e revacinadas 30 dias Bovine herpesvirus type 1 (BoHV-1) is recognized as a major cause of economic losses in cattle. Vaccination has been widely applied to minimize losses induced by BoHV-1 infections. We have previously reported the development of a differential BoHV-1 vaccine, based on a recombinant glycoprotein E (gE)-deleted virus (265gE -). In present paper the efficacy of such recombinant was evaluated as an inactivated vaccine. Five BoHV-1 seronegative calves were vaccinated intramuscularly on day 0 and boostered 30 days later with an inactivated, oil adjuvanted vaccine containing an antigenic mass equivalent to 10 7.0 fifty per cent cell culture infectious doses (CCID 50 ) of 265gE -. Three calves were kept as non vaccinated controls. On day 60 post vaccination both vaccinated and controls were challenged with the virulent parental strain. No clinical signs or adverse effects were seen after or during vaccination. After challenge, 2/5 vaccinated calves showed mild clinical signs of infection, whereas all non vaccinated controls displayed intense rhinotracheitis and shed virus for longer and to higher titres than vaccinated calves. Serological responses were detected in all vaccinated animals after the second dose of vaccine, but not on control calves. Following corticosteroid administration in attempting to induce reactivation of the latent infection, no clinical signs were observed in vaccinated calves, whereas non vaccinated controls showed clinical signs of respiratory disease. In view of its immunogenicity and protective effect upon challenge with a virulent BoHV-1, the oil adjuvanted preparation with the inactivated 265gE -recombinant was shown to be suitable for use as a vaccine.INDEX TERMS: Bovine herpesvirus type 1, BoHV-1, recombinant vaccine, inactivated vaccine.Pesq. Vet. Bras. 29 (7)

Impedimetric Biosensor for Bovine Herpesvirus Type 1‐Antigen Detection

“…The reaction was developed by incubation with peroxidase‐labeled anti‐IgY and a final step of adding 0.03 % H 2 O 2 and 1 mg/ml o‐phenylenediamine. The specificity of chicken positive sample (cut off) was arbitrarily defined as 2× the OD value of the negative serum .…”

Field Evaluation of Commercial Vaccines against Infectious Bovine Rhinotracheitis (Ibr) Virus Using Different Immunization Protocols

“…The serum neutralization (SN) test used to quantify BoHV-1 neutralizing antibodies in sera of cattle is recommended by the World Organization for Animal Health (OIE). SN has been used extensively to evaluate vaccines [ 11 , 12 , 13 , 14 ], although there is a difference in the titers obtained according to the sample used [ 15 ]. Moreover, it has been shown that the efficacy of the immune response against BoHV-1 depends on increased Th1-type cell-mediated responses [ 16 ].…”