Novel Acinar Metaplastic States Uncovered in Exocrine Pancreas Disease.

BACKGROUND & AIMS: In response to injury, pancreatic acinar cells undergo acinar-to-ductal metaplasia (ADM), marked by loss of acinar identity and acquisition of ductal features. Although ADM can resolve to support tissue repair, it may also persist and serve as a precursor to pancreatic cancer. Whether diverse pancreatic stressors drive a shared or context-specific ADM program remains unclear. We sought to comprehensively define metaplastic responses to clinically relevant exocrine pancreas diseases known to increase cancer risk.

METHODS

We profiled ADM and the surrounding microenvironment across mouse models of exocrine disease-including acute, recurrent, and chronic pancreatitis, as well as in the setting of oncogenic Kras-capturing over 300,000 single cells. To enable high-quality transcriptomic profiling in enzyme-rich tissue, we leveraged FixNCut, a method that preserves RNA integrity in the exocrine pancreas. Findings were validated in human pancreas tissue using CosMx spatial transcriptomics.

RESULTS

We identify a conserved acinar response across disease contexts that gives rise to previously unrecognized distinct metaplastic states, including a "gateway" ADM population that precedes more advanced metaplastic states marked by complete loss of acinar identity. In pancreatic intraepithelial neoplasia (PanIN) precancerous lesions, we detect classical-like and basal-like states, suggesting that pancreatic cancer subtypes are specified much earlier than previously appreciated. In Kras-mutant tissue, we identify a second wave of inflammation and the emergence of an immunosuppressive niche, coinciding with PanIN formation.

CONCLUSIONS

Our findings define a conserved program of acinar plasticity across exocrine pancreas diseases. We further link unresolved ADM to immune remodeling during precursor lesion formation and observe the emergence of pancreatic cancer subtypes in early PanIN lesions.