Production of polyclonal antibody against recombinant ORF 112 L of rock bream (Oplegnathus fasciatus) iridovirus (RBIV) and in vitro neutralization.

ABSTRACT

Rock bream iridovirus (RBIV) is a causative agent of epizootics among cultured rock bream (Oplegnathus fasciatus) in Korea. In this study, the immunogenic property of ankyrin repeats gene (ORF 112L) from RBIV was evaluated to develop vaccines against RBIV. ORF 112L of RBIV was cloned into expression vector of pGEX-4T-1. The recombinant protein was successfully expressed using E. coli BL21 (DE3). The soluble recombinant RBIV protein was applied to affinity column for the purification of the protein. Mice were immunized by the injection of purified recombinant protein to produce polyclonal antibodies. EUSA was carried out to identify the immune reaction abilities of polyclonal antibody to recombinant protein. The antigenic property of this protein was evaluated by using in vitro neutralization with BF-2 cells. In neutralization test, BF-2 cells infected with the mixture of RBIV and antisera containing anti-GST-ORF 112L polyclonal antibody were healthy showing few cytopathic effect (CPE) similar with the negative control (without RBIV). These studies suggest that the protein from the ankyrin repeats gene, ORF 112L of RBIV may play an important role in the mechanism of infection. Also, it can be possible to develop protein or gene vaccines using ORF 112L against RBIV.