Abstract:
An indirect sandwich ELISA that can detect as little as 8 ng of African horsesickness virus (AHSV)
was developed. Viral antigen was captured from suspension using an immobilized monoclonal antibody
specific for an epitope on VP7, a protein that is a major constituent of the virus core. Egg-yolk
derived chicken lgY directed against AHSV (serotype 3) was used as the secondary antibody. Since
lgY and mouse lgG do not cross-react serologically, the secondary antibody was not labelled, but
was instead detected with enzyme-coupled sheep antibodies directed against avian immunoglobulins.
The assay recognized all nine AHSV serotypes, but not the Cascara isolate of equine encephalosis
virus, a related orbivirus that also infects horses. In addition to being able to detect and quantify whole
AHSV, the ELISA could show the presence of VP7 produced by recombinant baculoviruses.
