title: Ultrastructural localization of intracellular antigens by the use of protein A-gold complex.
abstract: An immunocytochemical technique for the demonstration of intracellular antigens (secretory proteins) on thin sections is reported. Staphylococcal protein A which reacts with the Fc fragment of IgG molecules was labeled with colloidal gold as a marker. The antigenic sites were visualized on aldehyde-fixed and Epon-embedded tissue in a two step procedure. The specific antisera were applied to thin sections for binding to the antigens and then visualized by the protein A-gold complex. By using this technique different secretory proteins of the exocrine and endocrine pancreas were localized. The protein A-gold technique is proposed as a general method for visualization of antigenic sites on thin sections.
mesh_terms: D000818:Animals; D000941:Antigens / Q000302:isolation & purification*; D002417:Cattle; D006046:Gold; D007158:Immunologic Techniques; D007515:Islets of Langerhans / Q000276:immunology* / Q000648:ultrastructure; D008854:Microscopy, Electron; D010179:Pancreas / Q000276:immunology* / Q000648:ultrastructure; D011506:Proteins / Q000276:immunology*; D051381:Rats; D013205:Staphylococcal Protein A
chemical_list: D000941:Antigens; D011506:Proteins; D013205:Staphylococcal Protein A; D006046:Gold