Immunogold labeling of sections for Transmission Electron Microscope (TEM) allows detection of localization of proteins at high resolution. There are several ways of preparing samples for labelling. It is possible to do pre-embedding immunogold labeling. Another option is mild fixation and LR white embedding or the Tokuyasu technique. The Tokuyasu technique allows good antigen and structural preservation. The sample is infiltrated with sucrose, frozen and then cut in the frozen state to create ultrathin sections. After collection, the sections are warmed up to room temperature for the immunolabelling protocol.