FIG. 6.
Quantification of endocrine cells in large islets or sub–islet-sized endocrine clusters of. A: Relative abundance by immunofluorescence histology of β- and α-cells associated with islets or sub–islet-sized endocrine clusters in naïve and recently diabetic mice. Endocrine cells were counted from sections and subdivided in groups of small–endocrine cell clusters (<30 endocrine cells per cross section, □) or large islets (≥30 endocrine cells per cross section, ▩) and the sum of both (all islets, ■). The insulin-positive–to–glucagon-positive cell ratio of naïve C57BL/6 (n = 3) and naïve and diabetic Rip-CD80+GP+ mice (n = 3 and n = 5, respectively) was plotted for each islet size group. Insulin-, glucagon-, and somatostatin-positive cell frequencies were measured by flow cytometry in different pancreas compartments and from both naïve and recently diabetic mice. Purified islet cells (B and E) and viable, islet-depleted pancreatic tissue (C and F) were isolated from naïve (upper panels) and diabetic mice (lower panels). Representative flow cytometry plots and the calculated relative frequency of endocrine cell subsets are shown. D and G: The averages of insulin-positive–to–glucagon-positive cell ratios among islets and islet-depleted tissue (containing the small endocrine cell clusters) from healthy (n = 4) (D) and diabetic mice (n = 3) (G). depl., depleted; Gcg, glucagon; Ins, insulin; panc., pancreas. (A high-quality digital representation of this figure is available in the online issue.)