Figure 4. Glycogen accumulation in beta cells during autoimmune diabetes onset.
(a,b) A 3D double-tilt tomographic reconstruction analysis from a thin section shows a close association of glycogen particles (~35 nm in diameter) with membranes (in orange). (a) shows a slice through the tomogram, (b) a segmentation of the volume made with Amira (Visage Imaging). The particles lack systematic polyhedral appearance and differ in size. (c–f) Polysaccharide staining using the Thiery method (see Methods) reveals a fine speckled silver deposition on the particles, indicating that these are polysaccharide-rich. This fine precipitate is not present in the negative control, where periodic acid treatment has been omitted from the reaction33. Bars: 100 nm.