Infectious bursal disease virus structural protein VP 2 expressed by a fowlpox virus recombinant confers protection against disease in chickens

Abstract

Two fowlpox virus recombinants were constructed which expressed the host-protective antigen, VP2, of infectious bursal disease virus (IBDV). Recombinant FPV-VP 2.4.3 contained the gene for the VP 2-VP4-VP3 polyprotein under the control of the vaccinia virus late promoter P.L 11 inserted within the thymidine kinase (TK) gene of FPV. In infected chicken embryo skin (CES) cells VP2 and VP3 proteins were correctly processed from the polyprotein precursor molecule. Recombinant FPV-VP2 contained only the VP2 encoding region under the control of the fowlpox early/late promoter P.E/L inserted immediately downstream of the TK gene. The expression level of VP2 from FPV-VP2 was approximately 5 times higher than from FPV-VP2.4.3. Wing web inoculation of birds resulted in the development of typical fowlpox lesions and the development of antibodies to FPV with either of the recombinants, but only birds vaccinated with FPV-VP2 developed antibodies to IBDV. When challenged with IBDV (strain 002-73), a significant level of protection was provided by FPV-VP2 vaccination, although the level was lower than the protection provided by an oil adjuvanted inactivated whole IBDV vaccine. Birds vaccinated with FPV-VP2.4.3 were not protected from infection as assessed by ELISA for the presence of IBD virus in bursae.

Development of an Effective Polyvalent Vaccine against both Marek's and Newcastle Diseases Based on Recombinant Marek's Disease Virus Type 1 in Commercial Chickens with Maternal Antibodies

“…In the poultry industry, four recombinant viruses (rFPV [1,5,8,14,18,25,31,34,35,59], rHVT [13,17,28,41,44,53], adenovirus [51], and rMDV1 [45,47,49,54,62]) that express foreign antigens of other avian pathogens (including NDV [14, 17, 24, 28-30, 35, 47, 53, 58], MDV [31,33,42,44,69], infectious bursal disease virus [1,5,13,18,19,51,62], avian influenza virus [2,3,5,56,59,61,65,66], avian leukosis virus [34], and avian reticuloendotheliosis virus [8]) have been developed, and these viruses showed significant vaccine efficacy against a variety of avian diseases. Further, rHVT, rMDV1, and rFPV expressing NDV antigens have been constructed and used to FIG.…”

A Recombinant Newcastle Disease Virus (NDV) Expressing VP2 Protein of Infectious Bursal Disease Virus (IBDV) Protects against NDV and IBDV

“…VP2 and VP3 are the major capsid proteins of IBDV, constituting 51 and 40% of the viral proteins, respectively (25). The VP2 protein has been identified as the major host-protective immunogen of IBDV and contains major epitopes responsible for eliciting neutralizing antibodies (3,4,16). Passive antibodies to VP2 were found to protect chickens (12,25,44).…”

Recombinant Viral Vector Vaccines for the Veterinary Use.

“…Fowlpox virus (FPV) is the best characterized virus and the most frequently used as a viral vector in the avipox genus. Protective efficacy of chickens against avian influenza virus [6,107], NDV [9,84,109], infectious bursal disease virus [5,35], avian leukosis virus [82], avian reticuloendotheliosis virus [13], and Marek's disease virus [81] has recently been reported. Canarypox [110] and pigeonpox [58] vectors have also been described.…”