Immunocytochemical identification of dye-injected cells

Lucifer Yellow CH may be injected into pancreatic islet cells and visualized in Epon sections of the embedded tissue both before and after plastic removal and immunocytochemical staining. The dye retains its fluorescence, clearly marking the injected cell and adjacent dye-coupled cells, but does not interfere with the indirect immunofluorescent staining patterns that are characteristic of the islet cells.