A subset of pancreatic progenitor cells with the potential to differentiate to either endocrine cells or duct cells. These cells reside in a centrally located domain of the pancreatic epithelium. The majority of endocrine cells differentiate from these bipotent progenitors during the secondary transition. These cells' potential correlates with the phenotype of "trunk" cells (located in the trunk portion of the developing duct-acinar morphology).
Alternative lineage hypothesis exist, however this developmental mapping which includes a bipotent endocrine/duct progenitor cell is based on the excellent reviews by Pan 2011 and Pierreux 2010.