GCG and type 1 diabetes mellitus: EDX analysis showed high nitrogen content for both types of granules with an additional phosphorus signal in the endocrine granules in 6301 (autoantibody-positive) and 6228 (type 1 diabetes) donors (Fig. 3d lower panel and f), suggesting these contain glucagon, while intermediate cells in 6227 (control) and a subset in 6301 (autoantibody-positive) show sulfur-containing granules, suggesting these contain insulin (Fig. 3b and d upper panel).