Purification of equine infectious anemia virus antigen by affinity chromatography.

Affinity chromatography was performed to obtain highly purified antigen from equine infectious anemia (EIA) virus. After crude antigen was concentrated by polyethylene glycol precipitation of culture fluids from equine dermal cells persistently infected with EIA virus, and after the virus was disrupted with ether, it was added to a column of cyanogen bromide-activated Sepharose 4B to which EIA-specific antibody had been conjugated. The antigen was effectively released from the column with 5M MgCl2 and proved to be highly purified. Passive hemagglutination tests on sera from EAI infections were carried out, using the purified antigen. Results indicated that the passive hemagglutination test with the antigen was a specific laboratory test with high sensitivity for EIA infection.