Moreover, as shown in Figure 1F, the CK19/S100A9 double-staining experiment indicated that the S100A9 protein level was upregulated around the pancreatic duct (CK19-positive area) in AP mice, and some ductal cells expressed both CK19 and S100A9 (as shown by the arrow). This evidence concerns the gene S100A9 and alkaline phosphatase measurement.