Colloidal gold labeling of sections and cell surfaces

Colloidal gold labeling techniques can be simplified enough to become practical for diagnostic use in a hospital electron microscopy laboratory. Methods found to be practical and reproducible are presented, including production of colloidal gold reagents, polar embedding for gold labeling of thin sections, and use of silver enhancement on semithin sections. Methods for cell surface labeling are emphasized; they are technically straightforward and can be applied to investigation of multiple diagnostic problems.