The Establishment And Application Of Latex Agglutination Test Of GB Gene Of Duck Enteritis Virus

Duck viral enteritis (DVE), also known as duck plague (DP), which is an acute, heat andhaemorrhagic contagious viral disease caused by duck enteritis virus (DEV) in infected birds of theorder Anseriformes (ducks, geese and swans). DVE is characterized by spread rapidly, epidemicbroadly with high mortality and morbidity, it has been responsible for considerable economic lossto the commercial birds industry. DEV is a member of the herpesviridae according to it has theclassical morphology and structure of herpesvirus. Glycoprotein B is the highly conservedherpesvirus structural glycoprotein. It is required for herpesvirus infectivity. The glycoprotein B isinvolved in virus adsorption, membrane fusion,penetration and cell-cell spread. In addition, gBelicits neutralizing antibodies, and cell-mediated immune responses. Therefore, the research on gBhas significance on the clinical diagnosis, prevention, genetically engineered vaccine.The major antigenic domains of gB gene was amplified by PCR using a pair of primers andcloned into a prokaryotic expressive plasmid pPRO-EX-HTb. The recombinant plasmid pHTb-gBwas transformed into the E.coli BL21(DE3) and induced by IPTG. SDS-PAGE showed thatprotein gB was about36.0ku.It was in the form of inclusion body. Western blot analysis showedthat the purified recombinant protein had reacted with DEV positive serum specifically.The Latex Agglutination Test (LAT) to detect DEV was established.The carboxyl polystyreneof latex beads were used to link covalently to the protein gB. The result of selections showed thatthe best concentration of beads was1%, and the best concentration of protein gB was0.08mg/mL,and the best coupling time was6h. The coupled beads can detect the special antibody in seratowards gB of DEV.96duck seras were detected synchronously by LAT and ELISA.The resultdemonstrated that the coincident rate was95.8%between the two methods. In summery Latexagglutination test is a very simple, rapid and effective method and it could be used in fieldinvestigations.