The immunogold-silver staining procedure in the study of freshly suspended Langerhans cells at the transmission electron microscopic level.

The potential of an immunogold-silver staining for the study of human suspended Langerhans cells at the transmission electron microscopic level was evaluated. Cells were labeled, by using a preembedding technique, with 5-nm colloidal gold particles followed by silver enhancement. The use of small colloidal gold particles permits a detection of small quantities of antigen; the metallic silver deposition around gold granules gives rise to a large electron-dense marker which can be easily detected even at low magnification. Ultrastructural details were well preserved, and the background was not significant. The major advantage of the present immunogold-silver staining is that it enables to detect labeled cells easily, even when limited amounts of antigenic moieties are present on a low percentage of cells. Therefore, a rapid and simultaneous evaluation of both immunophenotype and ultrastructural details of investigated cells is allowed.