Protection against duck hepatitis a virus type 1 conferred by a recombinant avian adeno-associated virus

Abstract

The avian adeno-associated virus (AAAV) has been proved to be an efficient gene transfer vector for human gene therapy and vaccine research. In this experiment, an AAAV-based vaccine was evaluated for the development of a vaccine against duck hepatitis a virus type 1 (DHAV-1). The major capsid VP1 gene was amplified and subcloned into pFBGFP containing the inverted terminal repeats of AAAV, and then the recombinant baculovirus rBac-VP1 was generated. The recombinant AAAV expressing the VP1 protein (rAAAV-VP1) was produced by co-infecting Sf9 cells with rBac-VP1 and the other 2 baculoviruses containing AAAV functional genes and structural genes respectively, and confirmed by electron microscopy, Western blotting and immunofluorescence assays. Quantitative real-time PCR revealed that the titer of rAAAV-VP1 was about 9 × 1012 VG/mL. Immunogenicity was studied in ducklings. One day ducklings were injected intramuscularly once with rAAAV-VP1. Serum from rAAAV-VP1-vaccinated ducklings showed a systemic immune response evidenced by VP1-specific enzyme-linked immunosorbent assay and virus neutralization test. Furthermore, all ducklings inoculated with rAAAV-VP1 were protected against DHAV-1 challenge. The data of quantitative real-time RT-PCR from livers of challenged ducklings also showed that the level of virus copies in rAAAV-VP1 group was significantly lower than that of the PBS group. Collectively, these results demonstrate that the AAAV-based vaccine is a potential vaccine candidate for the control of duck viral hepatitis.

Construction and immune evaluation of the recombinant duck adenovirus type 3 delivering capsid protein VP1 of the type 1 duck hepatitis virus

“…DHAV1 is internationally widespread and can cause acute and highly lethal diseases of ducklings ( Wang et al, 2019a ). Common commercial attenuated vaccines against DHAV carry a potential risk of virulence reversion ( Kim et al, 2009 ; Wang et al, 2019a ), using vector vaccines can prevent this problem. DAdV3 is an emerging virus.…”

“…VP1 protein of DHAV contains B cell and T cell epitopes and can induce protective neutralizing antibodies, so the protein can be used for vaccine development and serological diagnosis ( Zhang et al, 2015 ). VP1 gene has been widely used in DHAV genotyping and molecular epidemiological studies ( Zhang et al, 2015 ; Wang et al, 2019a ). Since there is no effective vaccine against DAdV3, we intended to recombine the VP1 protein of DHAV1 into the entire genome of DAdV3 and construct a recombinant duck adenovirus to prevent and control DHAV1 and DAdV3 at the same time.…”

Recombinant Adenovirus Expressing Vesicular Stomatitis Virus G Proteins Induce both Humoral and Cell-mediated Immune Responses in Mice and Goats

“…rAd vector vaccines can be inoculated using a variety of methods since they have a wider range of permissive host cells. As effective vaccine vectors both the replicative and non-replicative adenovirus are long been used to infect a wide varieties of mammalian cells to to expression higher level of recombinant proteins [20][21][22][23][24][25]. Considering these advantages, it is valuable to perform further research for the development of vaccine candidates using an adenovirus vector for the prevention and control of VS.…”

Small but mighty: old and new parvoviruses of veterinary significance

“…These recombinant AAVs can be used to transduce avian neurons and retinal cells for manipulation of gene expression [ 217 ]. AAAV was used for the development of a vaccine against duck hepatitis A virus-1 [ 218 ].…”