Serological Detection of Grapevine leafroll virus 2 Using an Antiserum Developed against the Recombinant Coat Protein

Grapevine leafroll associated virus 2 (GLRaV 2) is one of the important components in the leafroll disease complex. The coat protein gene of GLRaV 2 was cloned into a protein expression vector pMAL-c2x and the recombinant protein, consisting of the maltose binding protein (MBP) and GLRaV 2 coat protein (CP), was expressed in Escherichia coli. The recombinant MBP-CP was used to raise a high quality antiserum. When used in Western blot analysis, the anti-MBP-CP antiserum produced specific reaction to the recombinant protein as well as to the viral coat protein of GLRaV 2. In Immunosorbent electron microscopy study, the anti-MBP-CP antibodies strongly decorated the GLRaV 2 virions. Using the newly developed antiserum, an indirect plate-trapped antigen enzyme-linked immunosorbent assay method was developed and successfully implemented for virus detection. A field survey was conducted to evaluate the virus infection status by GLRaV 2 and GLRaV 3 using antibodies developed against their respective recombinant coat proteins