title: Staphylococcal protein A in immunoferritin techniques.
abstract: Protein A (pA) of Staphylococcus aureus, by virtue of its reactivity with the Fc portion of a variety of mammalian immumoglobulins (IgG), can be used for electron-microscopical immunoferritin techniques. The conjugation of pA with ferritin (pA-F) by means of bis(4-fluoro-3-nitrophenyl) sulfone results in a highly specific marker for IgG in indirect labeling experiments. Native pA can be used as a noncovalent bridging agent between specific antibodies and antiferritin capturing the marker molecule. The use of pA and pA-F is demonstrated with a model system involving human erythrocytes and two rabbit antisera directed against different surface antigens of the human erythrocyte membrane.
mesh_terms: D000907:Antibodies, Bacterial; D001426:Bacterial Proteins / Q000276:immunology*; D003208:Concanavalin A / Q000276:immunology; D000939:Epitopes; D005293:Ferritins / Q000276:immunology*; D007106:Immune Sera; D007158:Immunologic Techniques; D008854:Microscopy, Electron; D013211:Staphylococcus aureus / Q000276:immunology
chemical_list: D000907:Antibodies, Bacterial; D001426:Bacterial Proteins; D000939:Epitopes; D007106:Immune Sera; D003208:Concanavalin A; D005293:Ferritins