Tff2 defines transit-amplifying pancreatic acinar progenitors that lack regenerative potential and are protective against Kras-driven carcinogenesis.

Abstract

While adult pancreatic stem cells are thought not to exist, it is now appreciated that the acinar compartment harbors progenitors, including tissue-repairing facultative progenitors (FPs). Here, we study a pancreatic acinar population marked by trefoil factor 2 (Tff2) expression. Long-term lineage tracing and single-cell RNA sequencing (scRNA-seq) analysis of Tff2-DTR-CreER^T2-targeted cells defines a transit-amplifying progenitor (TAP) population that contributes to normal homeostasis. Following acute and chronic injury, Tff2⁺ cells, distinct from FPs, undergo depopulation but are eventually replenished. At baseline, oncogenic Kras^G12D-targeted Tff2⁺ cells are resistant to PDAC initiation. However, Kras^G12D activation in Tff2⁺ cells leads to survival and clonal expansion following pancreatitis and a cancer stem/progenitor cell-like state. Selective ablation of Tff2⁺ cells prior to Kras^G12D activation in Mist1⁺ acinar or Dclk1⁺ FP cells results in enhanced tumorigenesis, which can be partially rescued by adenoviral Tff2 treatment. Together, Tff2 defines a pancreatic TAP population that protects against Kras-driven carcinogenesis.