Cytokeratin 19 or AE1 can be used to decorate the biliary epithelium in cases of chronic rejection, although it is usually not needed to find them. In this image, it is easy to see the cytokeratin positive bile ducts, which are being attacked by the infiltrating lymphocytes. Once the bile ducts have been completely destroyed, the lymphoplasmacytic portal infiltrate typical of chronic rejection will frequently disappear.