Comparisons of the pancreatic morphology and the numbers of β-cells, islet cell clusters (ICCs), and islets.

(A–C, A’–C’) The fluorescence micrographs show the expression of glucagon-positive cells (green) and insulin-positive cells (red). The nuclei are stained blue with Hoechst 33342. Immunofluorescence analysis of (A, A’) β-cells at 7 days of age; the cells comprise only insulin-positive cells, (B, B’) ICCs, at 35 days of age; the ICCs are not compact, and consist of aggregates of glucagon- and insulin-positive cells of various sizes, and (C, C’) islets from the splenic lobe (SL) at 180 days of age; the islets comprise denser cell populations, and the edges of the aggregates are well defined. All of the tissue sections were obtained from the SL. All panels are at the same magnification. Scale bars: 100 μm. (A”–C”) Comparisons of the numbers of (A”) β-cells, (B”) ICCs, and (C”) islets in each lobe during porcine pancreatic development. There were no significant differences between the SL and duodenal lobe (DL) at each time point analyzed. The numbers of β-cells, ICCs, and islets were counted in 3 different randomly selected 1.65 mm2-areas from 3 pigs for each day assessed. The data presented are the means atstandard errors of the means. The blue and orange bars indicate the SL and DL, respectively. SL versus DL: all P < 0.05. SEM = standard error of the mean.