Relation Between The Acute Rejection And The Frequencies Of HBV Specific CTLs In HBV Seropositive Liver Recipients

Though the advent of immunosuppressive agents contribute significantly to the progression of clinical transplantation, the attendant injure in long-term graft and recipient survival. To withdraw immunosuppressive agents is taken into account. But it should be based on the insight into the mechanism of rejection and immunosuppression, unfortunately we known little. It is critical to clarify the related factors with rejection. Face the fact of over 80% recipients of liver transplantation are HBV seropositive in China, we investigated the relation of acute rejection and HBV specific CTLs.1. Clinic study of the relationship between HBV-DNA and the acute rejection after Orthotopic liver transplantationRetrospective investigation and stratified statistics were performed of the 160 cases undergone in orthotopic liver transplantation in our unit during April of 2003 to October of 2005.The perioperative-period's treatment was followed the standard formulated by own protocal. The acute rejection diagnosis was identified with biopsy according to Banff Schema. All cases were divided into three groups as A(Non-detective) B(<105Cope) and C(≥105Cope) .The X2 statistic results had finded that the rate of AR was C group>B group >A group , especially B group was statistically diferent from C group .It was shown the rate of acute rejection associated with the amount of HBV-DNA and can be reasonablely presumed to associated with HBV specific CTLs2. Preparing of the single-chain MHC-peptide complex tetramer for detecting HBV specific CTLsDue to the small frequency epitope specific CTL, a sensible tetramers staining technology for detecting CTL was carried out. We constructed a single chain class I MHC by fusing the C terminus ofβ2m with extracellular domains of HLA A0201 connected with a accessional BSP by a linker. Expression of the recombinant in a pET systerm was followed by refolded in the presence of the antigenic peptide. After biotinylization of the MHC-peptide complex, the tetramers was obtained by the coupling of a fluorchrome conjugated streptavidin with the complex.3. Study on the relation of the acute rejection and the frequencies of HBV specific CTLs in HBV seropositive liver recipientsFor comprehensively reflected the influence of CTL in rejection, we constructed four tetramers contained a HBC, HBS, HBP, HBX epitope respectively. Enrolled HLA A2+ and HBV+ patients were undertaken commonly treatment. The correlation of rejection with the amount of CTLs before operation and in occurrence of rejection was analysed. In the 3 cases suffered AR out of 18 enrolled, the levels of CTLs were over the average, and was elevated little in the occurrence of rejection. In the contrast, no change were observed in other cases without rejection. It was suggested that there are some association between actue rejection with HBV specific CTLs.