title: Double-antibody method and the protein-A-bearing Staphylococcus aureus cells method compared for separating bound and free antigen in radioimmunoassay.
abstract: We compared the protein-A-bearing Staphylococcus aureus immunoadsorbent to the double-antibody precipitation method for separating bound and free radiolabeled antigen in a radioimmunoassay. With human albumin (antigen) and rabbit anti-human albumin (antibody) as a model, our results indicate that formalin-fixed, heat-killed S. aureus cells could be substituted for the double-antibody precipitation method. Ease of preparation and high adsorption capacity of protein-A-bearing S. aureus for most mammalian IgG make this method economical and time saving.
mesh_terms: D000906:Antibodies; D000937:Antigen-Antibody Reactions; D006801:Humans; D007074:Immunoglobulin G; D007164:Immunosorbents; D007457:Iodine Radioisotopes; D011233:Precipitin Tests; D011863:Radioimmunoassay / Q000379:methods; D013205:Staphylococcal Protein A / Q000032:analysis*; D013211:Staphylococcus aureus / Q000032:analysis*
chemical_list: D000906:Antibodies; D007074:Immunoglobulin G; D007164:Immunosorbents; D007457:Iodine Radioisotopes; D013205:Staphylococcal Protein A