Encephalomyocarditis Virus Hemagglutination-Inhibition Test Using Antigens Prepared in HeLa Cell Cultures

Abstract

A stable hemagglutinating antigen was prepared by alternate freezing and thawing of virus-infected cell cultures; optimal hemagglutination titers were obtained in the presence of K and B ions. A practical hemagglutination-inhibition system was developed with this antigen, BO3 - KCl diluent at pH 8, kaolin extracted serum and guinea pig or human erythrocytes. Clear-cut sedimentation patterns were obtained after 90 minutes at room temperature. Usefulness of the test was demonstrated in detecting antibodies in human and swine sera.