Construction Of Recombinant Rabbit Hemorrhagic Disease Virus (RHDV) Vaccine Using Myxoma Virus (MV) As A Vector

The Rabbit Hemorrhagic disease (RHD which caused by Rabbit Hemorrhagic disease virus (RHDV) is an acute and highly contagious disease with a high rates of death. The disease was first reported in China in 1984 and then also reported in other parts of the world. Infected rabbits usually die within 48 to 72 h of necrotizing hepatitis. The virion contains a 7.4Kb single-stranded positive-sense RNA genome. And there are two open reading frames there while ORF1 accounted for 94% of the entire genome, encoding a polyprotein which will decompose into structural proteins and non-structural proteins.the capsid protein VP60 is the major structural protein (5305-7041nt).Myxomatosis(MV) is considered the major viral diseases affecting European rabbit population as the Rabbit Hemorrhagic disease (RHD).MV is a pox virus specific infection in rabbits which belongs to the Leporipoxvirus genus of the Poxviridae family.Pox virus contains the promoter that can be recognized by eukaryotic cells.these promoters can active not only some gene markers commonly used in genetic engineering, but can also lead to expression of exogenous gene.In this study we have developed a recombinant virus using MV as a vector against both the myxomatosis and rabbit hemorrhagic disease (RHD) by using the nonessential gene MST3N of MV as the insertion site. The recombinant viruses expressed the RHDV major capsid protein (VP60) and the selectable marker GFP. The pure recombinant viruses were achieved after several rounds of plaque screening. Replication of MST3N-knockout recombinant virus MV-VP60 in Rabbit kidney cell (RK13) was unimpaired, compared with wild type virus MV. Following subcutaneous inoculation, the recombinant viruses induced specific antibody responses against RHDV and conferred protection against virulent MV challenges.