Figure 4.

Loss of Gα_z did not dramatically alter insulitis by 4 weeks of age, but it did reduce β-cell death. Pancreata were collected from female (♀) WT and Gα_z-KO mice at 4 weeks of age and subjected to hematoxylin and eosin staining. Insulitis was quantified using the previously described scoring system. (a) Percentage of islets in each of the scoring categories and (b) mean islet immune infiltration score for each biological replicate. (c–e) Additional pancreata were collected at 4 weeks of age and subjected to immunofluorescence analysis for insulin staining (red) and TUNEL assay (green), with a DAPI nuclear counterstain (blue). (c) Quantification of TUNEL⁺ β-cell nuclei calculated from all islets counted on three sections of each mouse pancreas separated by at least 200 μm. Representative TUNEL-stained pancreas sections from (d) WT mice and (e) Gα_z-KO mice are shown, with white arrows indicating TUNEL⁺ β-cell nuclei. In both images, the scale bar represents 100 μm. Data were compared by Student t test. (a, b) n = 7 per group; (c) n = 5 per group. All error bars represent standard error of the mean.