title: Detection of cell-bound immunoglobulins by a radioisotopic micro-mixed hemadsorption reaction with technetium-99m-labeled erythrocytes.
abstract: The mixed hemadsorption (MHA) reaction detects antibodies reactive with cell surface antigens by means of antiglobulin-coated indicator erythrocytes. We have developed a radioisotopic modification which employs sheep erythrocytes (SRBC) that have been prelabeled with technetium-99m (99mTc), a high specific acitivity metastable gamma-emitter of short half life. The 99mTc MHA reaction was performed on human and murine cells cultured in Micro-test II plated with six replicate wells per serum dilution. Antibody activity in species-specific xenoantisera and mono- and polyspecific alloantisera was detected in high titer. The sensitivity of 99mTc micro-mixed hemadsorption was 2 times that of the visual assessment of mixed hemadsorption, 100 to 200 times that of the 125-I-mixed antiglobulin reaction and 500 to 1000 times more sensitive than indirect immunofluorescence. The assay system was applied successfully to confirm the species of origin of a panel of previously karyotyped human and mouse cell lines. Our results indicate that the 99mTc micro-mixed hemadsorption method is a rapid, sensitive, quantitative test for the detection of cell surface antigens and membrane reactive antibodies.
mesh_terms: D000818:Animals; D000888:Antibodies, Anti-Idiotypic; D000918:Antibody Specificity; D000941:Antigens / Q000032:analysis; D002460:Cell Line; D004912:Erythrocytes / Q000276:immunology*; D005347:Fibroblasts / Q000276:immunology; D005455:Fluorescent Antibody Technique; D006367:HeLa Cells; D006382:Hemadsorption; D006801:Humans; D007111:Immunity, Cellular; D007136:Immunoglobulins / Q000032:analysis*; D007457:Iodine Radioisotopes; D007621:Karyotyping; D008253:Macaca mulatta / Q000276:immunology; D008545:Melanoma / Q000276:immunology; D008722:Methods; D051379:Mice; D010954:Plasmacytoma / Q000276:immunology; D012509:Sarcoma / Q000276:immunology; D013667:Technetium; D005719:gamma-Globulins / Q000302:isolation & purification
chemical_list: D000888:Antibodies, Anti-Idiotypic; D000941:Antigens; D007136:Immunoglobulins; D007457:Iodine Radioisotopes; D005719:gamma-Globulins; D013667:Technetium