Figure 1.

Murine liver organoids express markers of biliary differentiation. (A) Immunofluorescence staining of organoids reveals expression of biliary markers such as CK7, CK19, and SOX9. Scale bars correspond to 50 µm. (B) The adult murine liver contains only a minor fraction of EpCAM‐positive cells as determined by flow cytometry (left histogram), whereas nearly all liver‐derived organoids are EpCAM‐positive (right histogram). (C) Activation of a latent Kras^G12D and loss of p53 lead to increased proliferation as assessed by cell viability assay. (D) Schematic of the retroviral vector pSIN‐PGK‐CreERT‐IRES‐NeomycinResistance that was used to activate the latent Kras allele and delete p53 following tamoxifen treatment. Abbreviations: DAPI, 4′,6‐diamidino‐2‐phenylindole; RLU, relative light units; and SOX9, sex determining region Y (SRY)‐box 9.