Evaluation of recombinant fowlpox virus expressing infectious bronchitis virus S1 gene and chicken interferon-γ gene for immune protection against heterologous strains

• Published in: Vaccine Vol. 29; no. 8; pp. 1576 - 1582
• Main Authors: Shi, Xing-Ming, Zhao, Yan, Gao, Hong-Bo, Jing, Zhang, Wang, Mei, Cui, Hong-Yu, Tong, Gang-Zhi, Wang, Yun-Feng
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier Ltd 11.02.2011; Elsevier
• Subjects: Allergy and Immunology; Animals; antibodies; Antibodies, Viral - blood; Applied microbiology; Biological and medical sciences; Body Weight; CD4-Positive T-Lymphocytes - immunology; CD8-positive T-lymphocytes; CD8-Positive T-Lymphocytes - immunology; chickens; Chickens - immunology; Coronavirus Infections - immunology; Coronavirus Infections - prevention & control; Coronavirus Infections - veterinary; Fowlpox virus; Fowlpox virus - genetics; Fowlpox virus - immunology; Fundamental and applied biological sciences. Psychology; genes; IFN-γ; Infectious bronchitis virus; Infectious bronchitis virus - immunology; interferon-gamma; Interferon-gamma - genetics; Interferon-gamma - immunology; Kidney - pathology; Kidney - virology; Membrane Glycoproteins - genetics; Membrane Glycoproteins - immunology; Microbiology; Miscellaneous; morbidity; Poultry Diseases - immunology; Poultry Diseases - prevention & control; Recombinant fowl poxvirus; S1 protein; specific pathogen-free animals; Specific Pathogen-Free Organisms; Spike Glycoprotein, Coronavirus; Vaccination - veterinary; vaccines; Vaccines, antisera, therapeutical immunoglobulins and monoclonal antibodies (general aspects); Viral Envelope Proteins - genetics; Viral Envelope Proteins - immunology; viral shedding; Viral Vaccines - immunology; Virology; Virus Shedding; IFN-γ; S1 protein; Recombinant fowl poxvirus; Infectious bronchitis virus; Chordopoxvirinae; Farming animal; Poultry; Recombinant virus; Cytokine; Avian infectious bronchitis virus; Protein; Strain; Virus; Vertebrata; Avipoxvirus; Coronavirus; Gene; Poxviridae; Chicken; Aves; Coronaviridae; Veterinary; Nidovirales; Gamma interferon
• ISSN: 0264-410X; 1873-2518
• DOI: 10.1016/j.vaccine.2010.12.102

Abstract A recombinant fowlpox virus (rFPV-IFNγS1) that co-expressed the infectious bronchitis virus (IBV) S1 gene and the chicken interferon-γ gene has been constructed. To evaluate the efficacy of the recombinant fowlpox virus vaccine against heterotypic IBV strains, 60 4-week-old Specific-Pathogen-Free (SPF) chickens were inoculated with this vaccine and 3 weeks post inoculation challenged with the homotypic IBV strain LX4 and the heterotypic IBV strains LHB, LHLJ04XI, LTJ95I and LSC99I. Antibodies against IBV were detected in vaccinated chickens 1-week post inoculation. The number of CD4+ and CD8+ T-lymphocytes in the peripheral blood increased rapidly in the vaccinated groups challenged with strains LX4, LHB and LHLJ04XI. There were significant differences in the number of CD4+ and CD8+ T-lymphocytes between the vaccinated groups challenged with strains LTJ95I and LSC99I and all the control groups. The morbidity was below 30% in vaccinated groups challenge with strains LX4, LHB and LHLJ04XI, but was 40% greater than that in the other groups. In addition, the lesions and the amount of virus shedding were less severe in the vaccinated groups challenged by strains LX4, LHB and LHLJ04XI when compared with the other groups, but there was no significant difference in the average body weight of the chickens in all groups (all p > 0.05). These results indicate that the rFPV-IFNγS1 protected chickens against challenge with homotypic IBV strain LX4 and heterotypic strains LHLJ04XI and LHB.