Insulin and glucagon coexpression. Co-immunofluorescent images of islets from case 6185, sitagliptin (A–H) show endocrine cells coexpressing insulin (green) (A and E), glucagon (red) (B and F), and merged (D and H). The proportion of endocrine cells per islet that were thus detected as coexpressing insulin and glucagon was markedly increased
in DM-I. Confocal images are shown of an islet from case 6185 stained for insulin (green) (I) and glucagon (red) (J), and a merged image (K) shows a mixture of cells, some expressing insulin or glucagon only (arrowheads) and some showing coexpression (arrows).
DAPI nuclear counterstain (blue).