C. sinensis migrates into the bile duct of the host and lives there. However, the bile duct can be regarded as an extreme environment, since accumulation of bile juice can be toxic to the worm’s tissues and cells . Among the various bile juice, lithocholic acid (LCA) has been proven to have a toxic effect on the survival of juvenile C. sinensis . Therefore, it is important that the influx and efflux of bile acids should be balanced to prevent bile intoxication in the worm’s body. In humans, there are many importers and exporters of bile juice circulation , such as apical sodium-dependent bile acid transporter (ASBT), Na+ taurocholate co-transporting polypeptide (NTCP), Multidrug resistance protein (MRP), bile salts export pump (BSEP), and organic solute transporter (OST). Therefore, we believe that C. sinensis needs these bile transporters to reduce accumulation of bile acids within its body.