Spatiotemporal Dynamics of Bihormonal Cells in the Developing Human Pancreas

Studies of bihormonal cell distribution in the developing human pancreas are limited and focused on the first half of pregnancy. Here, we quantified the distribution of bihormonal insulin⁺/glucagon⁺ cells in different forms of the structural organization of the endocrine pancreas across gestational weeks 10-40. It was demonstrated that insulin⁺/glucagon⁺ cells are most abundant during early gestation (weeks 10-12) and prevail among single cells and small clusters throughout prenatal development, indicating that these cells belong to a population of immature endocrine cells. In the mantle and bipolar pancreatic islets, these immature bihormonal cells were located among α cells and were not detected among monohormonal β cells.