Mardik, N. R. | bioRxiv Science

bioRxiv2026

Metaplasia Orchestrates Tissue Recovery and Immune Remodeling Through CD73 in Chronic Pancreatitis

Chronic inflammatory injury promotes epithelial metaplasia, and progression from metaplasia to dysplasia is a recognized initiating event in carcinogenesis, as metaplastic cells exhibit heightened susceptibility to genetic alterations. In the pancreas, persistent acinar-to-ductal metaplasia (ADM) can progress to pancreatic intraepithelial neoplasia (PanIN), yet the mechanisms that determine whether ADM resolves or persists with fibrosis and sustained inflammation remain poorly defined. Here, we identify CD73 as a central regulator of ADM fate, tissue repair, and immune microenvironment remodeling during chronic pancreatic injury. Analysis of previously published single-cell RNA sequencing dataset from chronic pancreatitis (CP) tissues identified enrichment of Nt5e, which encodes CD73, within Hnf1{beta} ADM populations. Hnf1bCreERT2 and CD73fl/fl;Hnf1bCreERT2 mice were treated with caerulein for 4 weeks to induce pancreatitis and ADM prior to tamoxifen-induced deletion of CD73 in HNF1B-expressing metaplastic epithelial cells. Histologic phenotyping and immune profiling were performed using immunohistochemistry and imaging mass cytometry. Metaplasia-specific CD73 deletion exacerbated pancreatic injury and fibrosis, impaired epithelial proliferation and recovery of the acinar compartment, and altered the abundance and spatial organization of inflammatory cells. Ex vivo ADM assays further demonstrated that CD73 loss increased ADM formation and the production of MCP-1 and TIMP-1. These findings identify CD73 as a context-dependent checkpoint linking epithelial plasticity and immune modulation during chronic pancreatic injury and tissue repair.

cell biology↗

bioRxiv2026

Serial Thermal Ablation Induces Abscopal Antitumor Immunity and Reveals Targetable CSF1R-Dependent Resistance in Pancreatic Cancer

Thermal ablation is increasingly used for local control of pancreatic ductal adenocarcinoma (PDAC), but its capacity to induce systemic antitumor immunity and the mechanisms limiting this response remain incompletely defined. Using a bilateral LSL-KrasG12D/+; LSL-Trp53R172H/+; Pdx1-Cre (KPC) flank tumor model, we show serial radiofrequency ablation (RFA) enhances local tumor control and induces a robust abscopal response. This effect was associated with increased activation of CD8 T cells and natural killer cells, and was abrogated by CD8 T cell depletion. Single-cell RNA sequencing revealed expansion of cytotoxic immune programs alongside induction of a CSF1R-driven myeloid response consistent with adaptive immune resistance. Although combinatorial blockade of PD-L1 and CD73 augmented systemic antitumor responses, and the addition of CSF1R inhibition in this context further enhanced both local and distant tumor control. These findings identify a CSF1R-dependent myeloid resistance program which constrains ablation-induced systemic immunity and demonstrate that rational combination immunotherapy can potentiate the systemic efficacy of tumor ablation in PDAC. STATEMENT OF TRANSLATIONAL RELEVANCERadiofrequency ablation is a local thermal therapy that induces tumor destruction and modulation of the tumor microenvironment used for treatment of many solid tumors, including pancreatic cancer. Serial thermal ablations induce a CD8+ T cells and NK cell antitumor immunological response; however, Nt5e (CD73) is increased in tumor cells, PD-1 is increased in CD8+ T cells, and serial ablations increase a CSF1R+ macrophage cluster in ablated tumors. Combinational targeting of CD73, PD-L1, and CSF1R alleviates CSF1R-dependent therapeutic resistance and enhances local and systemic tumor control. This study identifies targetable countervailing mechanisms to local ablation therapy and provides a rationale for combinatorial strategies integrating serial tumor ablation with systemic immunomodulatory agents. Future prospective studies should evaluate the influence of timing, dosage, and sequence of ablation on immune priming to improve clinical interventions in pancreatic cancer.

cancer biology↗