Our basic aim is to pursue the pathophysiology of the liver from a pathological perspective and contribute to the development of new treatments for liver diseases. With a particular focus on the intrahepatic bile ducts, we are conducting immunopathological and molecular pathological analyzes of the carcinogenic mechanisms of intrahepatic cholangiocarcinoma and the pathophysiology of biliary diseases of unknown cause, such as primary biliary cirrhosis. We have also begun searching for human liver stem cells in order to establish regenerative medicine, which is the biggest challenge for the medical world this century. The main research topics are as follows. Research target diseases Elucidation of the carcinogenic mechanism and immune escape mechanism of intrahepatic cholangiocarcinoma Elucidation of the pathology and pathogenesis of primary biliary cirrhosis, hepatolithiasis, and idiopathic portal hypertension Physiological and pathological functions of cholangiocytes Elucidation of the pathology of congenital bile duct dysplasia and establishment of experimental models The origins of the human liver stem cell research group International joint research (University of California, Davis, Monash University, etc.) Intra-university joint research (1st Department of Internal Medicine, 2nd Department of Surgery, Department of Radiology) etc.) Joint research with other domestic universities (Nagoya University, Nagasaki University, Saga University, Hokkaido University, Tokushima University, etc.)