Demonstration of immunoglobulin M class antibodies to Toxoplasma gondii antigenic component p35000 by enzyme-linked antigen immunosorbent assay.
On the basis that 89% of 48 acute-phase toxoplasmosis patients showed immunoglobulin M (IgM) class antibodies to the 35,000-molecular-weight antigenic component (p35000) of Toxoplasma gondii, as demonstrated by IgM immunoblotting, the antigen was purified by sucrose gradient centrifugation and enzyme labeled for use in an enzyme-linked antigen immunosorbent assay (ELA) for the demonstration of IgM class antibodies to the p35000 component. The ELA showed a specificity of 96% with 139 serum specimens at a serum dilution of only 1:5. The test serologically detected 73 symptomatic acute-phase toxoplasmosis patients; 64 were positive in the 19S IgM indirect immunofluorescent-antibody test, and 9 were negative, although they showed IgM antibodies to p35000, as demonstrated by IgM immunoblotting. Also, the ELA turned out to be independent of IgM rheumatoid factors in six acute-phase toxoplasmosis serum specimens.
D000953:Antigens, Protozoan / Q000276:immunology*; D002499:Centrifugation, Density Gradient; D004797:Enzyme-Linked Immunosorbent Assay; D005455:Fluorescent Antibody Technique; D006801:Humans; D007124:Immunoenzyme Techniques; D007074:Immunoglobulin G / Q000032:analysis; D007075:Immunoglobulin M / Q000032:analysis*; D007158:Immunologic Techniques; D012217:Rheumatoid Factor / Q000276:immunology; D014122:Toxoplasma / Q000276:immunology*; D014123:Toxoplasmosis / Q000276:immunology*
D000953:Antigens, Protozoan; D007074:Immunoglobulin G; D007075:Immunoglobulin M; D012217:Rheumatoid Factor