Abstract
Immunocytochemistry, bridging morphology to biochemistry, has reached unsurpassed levels of sensitivity and resolution with the introduction of electron microscope markers using colloidal gold particles. The use of such markers has allowed for quantitative evaluations of antigens as well as multiple labelings of various antigens within the same cellular compartment. Other technological advances in tissue preparation techniques and molecular biology methods have significantly improved the versatility of immunocytochemistry. The advantages and some limitations of the new methods are discussed.