Fig 1.
Representative semithin and electron microscopy images of pancreatic cells in T2D slides.
A: Semithin section (stained with a 1:1 mixture of toluidine blue, 1% in bidistilled water, and methylen blue, 1% in bidistilled water) showing a cluster of 4 cells with islet-like appearance (magnification: 1,000x), enlarged in B (N: nucleus); C and D: Electron microscopy of cells containing both zymogen-like (black arrows) and insulin-like (white arrows) granules (magnification: 10,000x). ER in D indicates the endoplasmic reticulum, looking expanded and convoluted in this specific T2D beta cell.
Fig 2.
Electron microscopy images (magnification 10,000x) of pancreatic cells containing both zymogen-like (black arrows) and insulin-like (white arrows) granules in the four cases with T2D.
Fig 3.
Electron microscopy images (A and B, magnification 10,000x, with squares enlarged in a and b, respectively) showing pancreatic cells in T2D samples, containing both zymogen-like (black arrows) and insulin-like (white arrows) granules, and with cell membrane indicated by the dotted black arrows.
Fig 4.
Immunogold labeling of amylase (particle size: 5 nm) and/or insulin (particle size: 15 nm) in an acinar cell (A, square enlarged in a, showing only amylase particles), a beta cell (B, square enlarged in b, showing only insulin particles), and a hybrid cell (C, square enlarged in c, showing both amylase and insulin particles) in a T2D sample.
A, B and C: magnification 38,000x; the cell membrane is indicated by the dotted black arrows. Lymph indicates a lymphocyte close to the hybrid cell (see also Fig 7 for additional images of cells of the immune system).
Fig 5.
Immunogold labeling of amylase (particle size: 5 nm) and insulin (particle size: 15 nm) of an hybrid cell (magnification: 38,000x) in T2D samples, showing different cellular areas (numbered squares are enlarged) with both positivities in the cytoplasm.
Fig 6.
Confocal microscopy images of double immunohistochemical stainings for insulin (green), the acinar enzyme carboxypeptidase A (red) or both the markers (yellow in merge panels).
Blue staining is DNA (DAPI, Hoechst dye. Representative cells are shown from a control non-diabetic subject (left panels) and from a subject with type 2 diabetes (right panel).
Fig 7.
Representative image (left panel) of a pancreatic cell in T2D samples containing both amylase (black arrows) and insulin (white arrows) granules, with adjacent cells of the immune system.
The image has been reconstructed from several pictures at 10,000x final magnification. Enlargments are provided in the right panels. Mc: macrophage, Lymph: lymphocyte, Ms: mast cell.