Developmental Lineage of Pancreatic Acinar Cells

Pancreatic acinar cells originate from definitive endoderm cells that form during gastrulation, and then undergo patterning along anterior/posterior, dorsal/ventral, and median/lateral axes, producing, among other embryonal cell types, endoderm cells of dorsal and ventral foregut, which, after transitioning through an intermediary duodeno-pancreatic endoderm cell state for dorsal foregut endoderm and possibly a hepato-pancreatic or pancreato-biliary intermediary state for ventral foregut endoderm, give rise to multipotent pancreatic progenitor cells (MPCs) that form dorsal and ventral pancreatic buds (Yu et al. 2019, reviewed in Jennings et al. 2015). Developing pancreas undergoes branching morphogenesis, which results in the apical-basal polarity that is critical for establishing the acinar-ductal functional unit. Both dorsal and ventral MPCs located at the tips of the developing, branching pancreas, start committing to the acinar cell fate from Carnegie stage 19 (45-47 days post conception) of human embryonic development and around embryonic day E12 during mouse development, initially becoming distinct tip progenitors, and then pro-acinar and acinar cells (Yu et al. 2019, reviewed in Jennings et al. 2015).