GCG and type 1 diabetes mellitus: To this end, PC1/3 protein expression in individual alpha, beta, and delta cells from AAb+ donors and donors with recent-onset or short duration type 1 diabetes (<5 years), long-duration type 1 diabetes (>15 years), type 2 diabetes and non-diabetic donors were evaluated via multiplex immunostaining, confocal imaging and high-dimensional image analyses, including islet cell morphology, PC1/3 expression and co-localisation of insulin and glucagon at the single-cell level, as well as glucagon- and somatostatin-positive areas in the islets.