Solid-phase radioimmunoassay of rubella virus immunoglobulin G and immunoglobulin M antibodies

Abstract

A solid-phase radioimmunoassay method was developed for the detection of rubella virus-specific immunoglobulin G (IgG) and IgM antibodies in human serum specimens. Purified rubella virus was adsorbed onto polystyrene balls, and antibodies that attached to the virus-treated balls were detected by subsequent binding of 125I-labeled [rabbit] anti-human .gamma. or anti-human .mu. immunoglobulins; 77 serum specimens were tested. Binding ratios between positive and negative sera were as high as 22 in the IgG assay but rarely exceeded 3 in the IgM assay. The sensitivity of the IgG assay was 16-256 times higher than that of the rubella virus hemagglutination inhibition test. The IgG radioimmunoassay can be readily adopted for routine diagnostic use. The IgM radioimmunoassay, due to its lower sensitivity, must be modified before being routinely applied.