title: Quantitative immunoautoradiography at the cellular level. I. Design of a microphotometric method to quantitate membrane antigens on single cells using 125I-labeled antibodies.
abstract: Iodine-125 has become a commonly-used radioisotope, especially for immunoautoradiographic investigations. Microphotometry of grain density, a well-established method in autoradiography with tritium and carbon-14, was applied to nucleated cells with 125I-labeled membranes. Geometric and absorption factors of radiation were investigated in order to find suitable conditions for quantitative evaluation. A preparatory device is given and a set-up of appropriate measuring conditions is presented. With these prerequisites the reflected-light bright-field photometry of immunoautoradiographs permits to determine automatically the content of surface antigens of single cells. Measurement examples were demonstrated.
mesh_terms: D000818:Animals; D000918:Antibody Specificity; D000941:Antigens / Q000032:analysis*; D001345:Autoradiography / Q000379:methods*; D002462:Cell Membrane / Q000276:immunology*; D002846:Chromatography, Affinity; D002848:Chromatography, DEAE-Cellulose; D003168:Complement Fixation Tests; D003601:Cytotoxicity Tests, Immunologic; D006801:Humans; D007106:Immune Sera; D007457:Iodine Radioisotopes; D007553:Isotope Labeling; D008198:Lymph Nodes / Q000166:cytology; D008214:Lymphocytes / Q000276:immunology; D008854:Microscopy, Electron; D010544:Peroxidases; D010783:Photometry; D013154:Spleen / Q000166:cytology; D013950:Thymus Gland / Q000166:cytology
chemical_list: D000941:Antigens; D007106:Immune Sera; D007457:Iodine Radioisotopes; D010544:Peroxidases