Figure 5
2D CLEM experiment of 81.9 nm diameter fiducials on top of a 70 nm thick cryosection of HT1080 cells stably expressing LAMP-1-GFP. (a) Widefield fluorescence microscopy image. (b) Region selected for TEM imaging. (c) TEM image of the selected region (fiducials encircled in red). (d) Overlay of FM and EM data based on the positions of the particles. In (e) and (f) higher magnification CLEM and TEM images of the in (d) highlighted region are included. The GFP fluorescence perfectly overlaps with the position of late endosomes and lysosomes, which were identified in TEM by their ultrastructural characteristics and the presence of endocytosed BSA-Au5 (arrowheads). In the inset of (f) one of the fiducials is enlarged, highlighting the core-shell structure of the particles.
