Attenuation of bovine herpesvirus type 1 by deletion of its glycoprotein G and tk genes and protection against virulent viral challenge.

Abstract

To develop a novel vaccine against infectious bovine rhinotracheitis (IBR), a bovine herpesvirus-1 (BoHV-1) mutant was constructed by deleting the genes for glycoprotein G (gG) and thymidine kinase (tk) through homologous recombination. The resulting sequences for both genes were shown to be correct and a gG expression defect was also confirmed. A parallel study of the BoHV-1 gG(-)/tk(-), gE(-)/tk(-) mutants and wild type (wt) in 31 calves was performed at three different doses, 4×10(5)PFU, 4×10(6)PFU and 4×10(7)PFU. Compared to wt BoHV-1, inoculation of BoHV-1 gG(-)/tk(-) and gE(-)/tk(-) produced no clinical signs and the virus was not reactivated by dexamethasone (dex). Inoculation of BoHV-1 gG(-)/tk(-) at the doses of 4×10(6) and 4×10(7)PFU provided full clinical protection for the cattle against wt BoHV-1 challenge at 4×10(7)PFU/calf. Although the mutants were associated with significantly lower levels of serum neutralizing antibody, interferon gamma (IFN-γ) and tumor necrosis factor alpha (TNF-α) than wt BoHV-1 on days 3, 5 and 7 after immunization, stimulation of IFN-β by BoHV-1 gG(-)/tk(-) was significantly higher than that of wt BoHV-1 and gE(-)/tk(-) on days 3 and 5. We conclude that BoHV-1 gG(-)/tk(-) was attenuated adequately and that it maintains the ability to stimulate immune protection. Therefore, it may be a promising candidate for a marker vaccine against IBR.

• Authors: Minmin Zhang, Shulin Fu, Mingliang Deng, Qian Xie, Haiyang Xu, Zhengfei Liu, Changmin Hu, Huanchun Chen, Aizhen Guo
• Journal: Vaccine (Vaccine) Vol. 29 Issue 48 Pg. 8943-50 (Nov 08 2011) ISSN: 1873-2518 [Electronic] Netherlands
• PMID: 21959327 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
• Copyright: Copyright © 2011 Elsevier Ltd. All rights reserved.

Chemical References

• Antibodies, Neutralizing
• Antibodies, Viral
• Tumor Necrosis Factor-alpha
• Viral Proteins
• Viral Vaccines
• bovine herpesvirus type-1 glycoproteins
• Interferon-gamma
• Thymidine Kinase

Topics

• Animals
• Antibodies, Neutralizing (blood)
• Antibodies, Viral (blood)
• Cattle
• Cell Line
• Female
• Gene Deletion
• Herpesvirus 1, Bovine (genetics, pathogenicity)
• Infectious Bovine Rhinotracheitis (immunology, prevention & control)
• Interferon-gamma (immunology)
• Male
• Rabbits
• Thymidine Kinase (genetics)
• Tumor Necrosis Factor-alpha (immunology)
• Viral Proteins (genetics)
• Viral Vaccines (genetics, immunology)
• Virus Shedding