Protection of Chickens from Newcastle Disease and Infectious Laryngotracheitis with a Recombinant Fowlpox Virus Co-Expressing the F, HN Genes of Newcastle Disease Virus and gB Gene of Infectious Laryngotracheitis Virus

Abstract

A recombinant fowlpox virus (rFPV) coexpressing the Newcastle disease virus (NDV) fusion and hemagglutinin-neuraminidase genes and infectious laryngothracheitis virus (ILTV) glycoprotein B gene was constructed. This virus was then evaluated for its ability to protect specific-pathogen-free (SPF) chickens against clinical symptoms and death after challenge by virulent NDV and ILTV. SPF chickens were grouped and vaccinated with the rFPV and commercial NDV (La Sota) and ILTV attenuated live vaccine (Nobilis ILT), respectively. After challenge with NDV 10 days postvaccination, 70% of chickens vaccinated with rFPV were protected from death, whereas 100% of the commercial NDV-vaccinated chickens were protected from death. In contrast, 100% of the unvaccinated chickens died after challenge. After challenge with ILTV, both the rFPV and commercial ILTV-vaccinated chickens were completely protected from death and 70% of chickens were protected from respiratory signs. In comparison, 100% of the unvaccinated chickens developed severe respiratory disease and 10% of chickens died. The protective efficacy was also measured by the antibody responses and isolation of challenge viruses. Results showed that this rFPV could be a potential vaccine for preventing NDV and ILTV by a single immunization.

Chicken interferon gamma fold expression level and tracheal lesion score differences between commercial broiler chickens vaccinated with live and vectored ILT vaccines

“…It has been shown that the ILTV gB protein assembles into homodimers that are rapidly cleaved to form two disulphide-linked species (20). Recombinant fowlpox virus-vector vaccines expressing the ILTV gB gene, and a DNA vaccine containing the gB gene, have also been developed and have been shown to provide protective immunity in chickens (3,7,26,30).…”

Pair-epitopes vaccination: enabling offspring vaccination in the presence of maternal antibodies

“…This approach can be implemented for viruses that carry two proteins, for example, F and HN of NDV (Boursnell et al, 1990;Cosset et al, 1991;Karaca et al, 1998;Sun et al, 2008;Kumar et al, 2011), each containing multiple neutralizing epitopes. Such a combination may very well be successful.…”

Immune responses of chickens inoculated with a recombinant fowlpox vaccine coexpressing glycoprotein B of infectious laryngotracheitis virus and chicken IL-18

“…York & Fashey (1991) reported a subunit vaccine made of a 205-kDa complex containing gB protected 100% of chickens against clinical disease and also against viral replication. Sun et al (2008) found that their constructed rFPV co-expressing the F and HN genes of Newcastle disease virus and the gB gene of ILTV protected 100% of the chickens from death and 70% of the chickens from respiratory signs against an ILTV challenge. These studies prove that gB is a major protective immunogen of ILTV.…”

“…The results showed that vaccination with the rFPV-gB/IL18 can induce stronger immune responses than vaccination with rFPV-gB or ILTV attenuated vaccine. Compared with some earlier descriptions of FPV recombinants expressing ILTV gB (Tong et al, 2001;Sun et al, 2008), cytokine chicken IL-18 and different ILTV strains were used. Tong et al reported that the SPF and commercial chickens immunized with rFPV-ILTVgB were all 100% protected from death and three 12-week-old SPF chickens immunized by eye-drop with rFPV-ILTVgB had clinical signs of ILTV infection after challenge with an ILTV WG virus.…”

“…Tong et al reported that the SPF and commercial chickens immunized with rFPV-ILTVgB were all 100% protected from death and three 12-week-old SPF chickens immunized by eye-drop with rFPV-ILTVgB had clinical signs of ILTV infection after challenge with an ILTV WG virus. A FPV (rFPV-F/ HN/gB) co-expressing F, HN genes of Newcastle disease virus and gB gene was constructed by Sun et al (2008). One hundred per cent of SPF chickens immunized with rFPV-F/HN/gB were protected from death and 70% of SPF chickens were protected from respiratory signs after challenge with an ILTV WG virus.…”