NT5E and chronic pancreatitis: We determined the localization of CD73 in vivo by CD73 IHC staining and observed a strong positive expression of CD73 on infiltrating immune cells as well as ductal cells only in wild‐type mice under chronic pancreatitis, whereas the absence of CD73 expression was confirmed in pancreata from the in CD73−/− mice (Figure 2B, Top panels, black arrows).