Abstract: Objective To explore the trend of changes of Th1 and Th2 cytokines within 6 months after adult liver transplantation (LT). Methods Twenty-three patients from Tianjin First Center Hospital were chosen as the patient group with an average age of (52.7±7.6), range from 37 to 63 years old, including 21 males and 2 females. Twenty healthy staffs from Tianjin First Center Hospital formed the control group (C) with 15 males and 2 females whose average age was (31.0 ± 6.1) ranged from 22 to 24 years old. The patient group was treated with tacrolimus after LT as main immunosuppressive drug. The peripheral blood at time points before (T0) and 1 month (T1), 3 months (T3), 6 months (T6) after LT at 9:00 AM were collected. The blood sample was also collected form control group but only one time. Levels of IL-2, IFN-γ, IL-10 and TGF- β were detected by ELISA. Results (1) The concentration of IL-2 showed a continuous up-going trend, which was not such obvious between T1 and T0, and until T3 reached a higher concentration than T0. The concentration at T6 was higher than T0 and T1. There were no significant differences in concentrations of T0 to T3 between patient group and control group, while T6 reached a higher concentration in patient group than that of the control group. (2) The concentration of IFN- γ experienced a shortly down-going trend from T0 to T3, and started rising, reached the peak at 3 months after the operation, then started its down-going trend. There were no significant differences in the concentrations of IFN-γ from T1 to T6, and T3 reached a higher concentration than T1 while T6 was lower than T3. Only at T3, the concentration of IFN-γ was higher in patient group than that of control group. (3) There were no significant differences in the concentrations of IL-10 at various time points in patient group, and there were no significant differences in the concentrations of IL-10 at different time points between two groups (P＞0.05). (4) The concentration of TGF-β showed a gradual decline after the operation, and reached its bottom at T6, and which was lower than T0 to T3. Compared with the control group, the down- going trend was not such obviously at T0 and T1, and the concentration was down at T3 and T6（P＜0.05） . Conclusion Our results suggest that there is a tendency of an increasing Th1 cytokine expression at early stage in post-transplantation, while the TGF-β of Th2 cytokine is a decreasing trend. This tendency may associate with the autoimmunity response caused by LT and the immunosuppressive drugs.

Key words: liver transplantation, cytokines, Th1 cells, Th2 cells, interleukin-2, interleukin-10, transforming growth factor beta, interferon type Ⅱ