ObjectiveTo investigate the early diagnostic value of transforming growth factor-β1(TGF-β1) on acute rejection after liver transplantation in rhesus by detecting the expression of TGF-β1 in the liver tissue. MethodsLiver transplantation models in rhesus were constructed by the improved vascular dual cuff, supporting tube of biliary tract, and artery anastomosis method.The successful models were randomly divided into experimental group (no immunosuppressant treatment in perioperative period) and control group (treated by immunosuppressant in perioperative period).Then the blood samples and liver tissues were collected at 6, 12, 24, and 72 hours after surgery.Allograft rejections of liver tissue after liver transplantation were monitored by liver function test, hematoxylin-eosin staining and Banff score.Finally, the expression level of TGF-β1 was detected by Western blot analysis or immunohistochemistry technique. Results①The acute rejection happened in all the rhesus at 12 h, 24 h and 72 h after liver transplantation, especially at 72 h after liver transplantation in the experimental group, the Banff grade levels of acute rejection in the liver tissue was more severe than that in the control group (P < 0.05).②The levels of ALT, AST, and TBIL after liver transplantation was gradually increased, which were similar at 6 h and 12 h after transplantation between the two groups, but which at 24 h and 72 h after transplantation in the experimental group were significantly higher than those in the control group (P < 0.05).③The results of TGF-β1 protein expression using immunohistochemical detection:The percentage of positive area of TGF-β1 of liver tissue at 12 h in the experimental group was significantly higher than that in the control group (P < 0.05).With the extension of time, it was gradually increased and significantly higher than that in the control group at 24 h or 72 h (P < 0.05).④The semi-quantitative results of TGF-β1 protein expression using Western blot detection:The TGF-β1 protein expressions began to increase at 6 h after liver transplantation in the experimental group and the control group, and the magnitude of increase was more obvious in the experimental group.The TGF-β1 protein expressions at different time (6 h, 12 h, 24 h, and 72 h) in the experimental group were significantly higher than those in the control group (P value was 0.003, 0.001, 0.001, and 0.001, respectively). ConclusionsThe elevated level of TGF-β1 of liver tissue after liver transplantation might suggest the enhanced cellular immune function, it might have certain significance for early diagnosis of acute rejection after liver transplantation.