Abstract: Objective This case control study aimed to detect and analyze the expression of bile acid transporters BSEP, MRP2, MDR3 in liver tissues of patients with jaundice after liver transplantation, and to explore the role of bile acid metabolism in its generation and development. Methods In the case control study, 25 cases with jaundice and liver puncture after liver transplantation in Nanjing Military Area Command Fuzhou General hospital form 2006 to 2017 were selected. 18 cases with hepatic hemangioma were selected as control group. Clinic data and paraffin block of liver biopsy tissue were collected on all patients. The liver specimens were performed for histopathological and immunohistochemical examinations. Immunohistochemistry was performed to detect the expression of BSEP, MRP2 and MDR3 in the liver tissues of two groups. Semi-quantitative analysis was applied to compare the expression difference of the above bile acid transporters in liver tissues of control group, the liver transplantation group and the jaundice group after liver transplantation caused by various causes. Results The total expression level of BSEP, MRP2 and MDR3 in jaundice liver tissue after liver transplantation was lower than that of the control group (P<0.05), but there is a difference between different causes: only the expression of BSEP in the liver tissues with jaundice caused by rejection, viral factors and bile duct obstruction after liver transplantation was significantly lower than that in the control group (P<0.001, P=0.002, P=0.035). MRP2 expression in liver tissues with jaundice caused by viral factors was lower than that in the control group. The expression of MDR3 in the liver tissues with jaundice caused by post-transplantation rejection (P=0.001), ischemia-reperfusion injury (P=0.011), drug toxicants (P=0.047) and obstructive factors (P=0.01) was significantly higher than that in the control group. Conclusion The down-regulated of bile acid efflux proteins BSEP, MRP2 and MDR3 in the liver tissue of patients with jaundice after liver transplantation suggested that they may play an important role in the pathogenesis of cholestasis after liver transplantation, but the expression levels of above-mentioned proteins in patients with different etiologies are different.

Key words: Cholestatic liver diseases, Liver transplantation, Bile acid transporters