Detection of enterovirus specific IgG and IgM antibodies in humans by an indirect solid phase radioimmunoassay.

The development of a solid phase radioimmunoassay which is able to detect virus-specific IgG and IgM antibodies in serum specimens from patients with enterovirus infections is described. Viral antigen partially purified from infected tissue culture fluid was absorbed passively to individual polystyrene microtiter wells. Dilutions of sera were incubated on these antigens and bound anti-viral antibodies were monitored by the addition of 125-iodine labeled anti-human-IgG or anti-human-IgM antibody. Specificity of the assay to detect virus-specific IgM antibody was ensured by highly specific anti-IgM antibody which did not cross react with IgG and 2-mercaptoethanol sensitivity of IgM antibody titers. Changes of IgM antibody titers clearly indicated a current infection by that virus strain which was isoalted as etiological agent. Advantages and restrictions of the introduced radioimmunoassay are discussed.