Objective To study the mechanism of immune hyporesponsiveness of allograft rejection induced by transfusion nonpufsed allopeptide syngeneic immature dendritic cell (imDC) generated from recipient bone marrow progenitors and to explore a possible strategy for liver allograft protection in clinic. Methods Forty experimental rats were randomly divided into 4 group: control group, cyclosporine A (CsA) group, mature DC (mDC) group and imDC group. In control group, Wistar rats only received liver transplantation. In CsA group, Wistar rats underwent liver transplantation plus CsA treatment 〔10 mg/（kg·d)〕. In mDC group, recipient-derived mDC 1×106 were infused intravenously through the penile vein to Wistar rats. In imDC group, ImDC with the dose of 1×106 were injected into Wistar rats via the dorsum vein of penile. In each group, five recipients were killed on the 10th day after transplantation, the other five recipients were left to observe survival time. The levels of ALT, AST, TBIL, IL-2, IFN-γ, IL-4 and IL-10 were detected. The acute rejection and the expression of FasL/Fas in the grafts were detected by HE and immunohistochemical staining. Western blot was used to detect Scurfin protein expression of CD4+ CD25+ T cells. Results The median survival time of the liver allografts in CsA group and imDC group were significantly longer than that in control group and mDC group ( P ＜ 0.05). The levels of ALT and TBIL in control group and mDC group were significantly higher than those in CsA group and imDC group ( P ＜ 0.05). Compared with CsA group and imDC group, the levels of IL-2 and IFN-γ were higher but the levels of IL-4 and IL-10 were lower in control group and mDC group ( P ＜ 0.01). Slightly or no rejection reaction was found in CsA group and imDC group ( P ＜ 0.05). The Scurfin protein expressions of CD4+ CD25+ T cells of imDC group were significantly higher than those of other three groups. Conclusion Application of nonpufsed allopeptide syngeneic recipient-derived imDC is an effective way to induce immune hyporesponsiveness by blocking indirect recognition in rat liver transplantation model. Survival span is significantly prolonged by its protective effect. The mechanism of immune hyporesponsiveness induced by imDC transfusion might be involved in some aspects: T cell apoptosis, immune deviation of Thl/Th2 cytokine net and inhibition of T lymphocytes responsiveness by regulatory T cells.
【Abstract】Objective To evaluate the pathological diagnosis of liver allograft rejection. Methods Literatures about diagnosis of liver transplantation rejection in recent ten years were reviewed.Results Humoral rejection was rare. The main features were graft blood vessel thrombosis and liver damage and necrosis about some days or one week after transplantation. The humoral rejection of liver graft occurred later than that of kidney and heart transplantation. The diagnosis of acute liver graft rejection was based on Banff Schema. During chronic rejection intrahepatic bile ducts among hepatic lobules in portal area disappeared, and inflammation, fibrosis and stricture of hepatic arteries and veins were found, but the morbidity was less than that of kidney， heart, lung and pancreas grafting. Conclusion Banff standard is the most important base of diagnosing liver graft rejection.
Objective To investigate the expression of RNA editase ADAR1 in the lymphocytes in rats’ spleen with liver transplantation rejection. Methods Thirty SD rats and 75 Wistar rats were included. Fifteen livers from Wistar rats were transplanted to 15 Wistar rats (isograft group), 30 livers from SD rats were transplanted to 30 Wistar rats (allograft group and allograft+FK506 group), and 15 of them were then intramuscularly injected with FK506, 2 mg/(kg·d), the other 15 Wistar rats were only operated similarly to the other rats without any liver transplantation (control group). Five rats were killed and their splenetic tissues were collected on day 3, day 5, and day 7, respectively. The expression of ADAR1 mRNA in lymphocytes of the spleen in acute rejection was detected by RT-PCR. Results Different performance of pathology was observed in all the liver and spleen tissues from the transplanted rats over time, especially in allograft group. The expression of ADAR1 mRNA in the allograft group was significant higher than that of isograft and allograft+FK506 groups （P＜0.001）, especially on the 5th day. Conclusion There was a significant positive correlation between expression of ADAR1 and the severity of acute rejection, but the mechanism by which ADAR1 affected the acute rejection is unknown and needs to be further studied. FK506 may inhibit the expression of ADAR1 and remarkably reduce the severity of acute rejection.
Objective To investigate the effect of interleukin-10 （IL-10） gene transfer on expression of CD44, selectin-E, lymphocyte function associated antigen-1 （LFA-1）, vascular cell adhesion molecule-1 （VCAM-1） in mice heart transplantation rejection. Methods Model of mice cervical heterotopic heart transplantation was set up, 96 mice were divided into three groups with random number table, control group： heart transplantation between C57 mice; transplant group： heart from BALB/C mice transplant to C57 mice; IL-10 group： IL-10 was transfected on BALB/C mice isolated heart for 1 hour, then transplanted to C57 mice. The messenger ribonucleic acid （mRNA） level expression of CD44 ,selectin-E ,LFA-1 ,VCAM-1 and IL-10 were measured by reverse transcription-polymerase chain reaction （RT-PCR） at the 5th day after transplantation. Results The mRNA level expression of CD44, selectin-E ,LFA-1 ,VCAM-1 in transplant group were significantly increased than those in control group （P〈0.01）. The mRNA level expression of CD44, selectin-E, LFA-1 ,VCAM-1 in IL-10 group were significantly decreased than those in transplant group （P〈0.01）. Conclusion IL-10 gene transfer is able to decrease the expression of CD44, selectin-E,LFA-1 ,VCAM-1 and suppress the heart transplantation rejection in mice.
ObjectiveTo compare tacrolumus (FK506) with cyclosporine A (CsA) in clinical application to organ transplantation.MethodsThe literature in recent years has been reviewed and compared. ResultsFK506 was a powerful immunosuppression with a mechanism of action similar to that of CsA, but significantly superiori to CsA in terms of prophylaxis and treatment of allograft acute rejection, delay of chronic rejection, and withdrawal of steroid in early period. The cardiovascular mortality and chronic graft nephropathy (CGN),such as hypertension and hyperlipidemia were less frequently seen in FK506treated patients and FK506 also had an acceptable safety profile, including a low incidence of hypertrichosis,gingival hyperplasia and infections.However, CsA had been showed a better result in prevention of posttransplantation diabetes mellitus (PTDM ) and more economic agent than FK506. Pharmacokinetic studies showed CsA in the form of Sandimmun Neoral showed less inter an intrapatient variability than FK506.Meanwhile, the combination of MMF and FK506 or CsA has been proved effectively with excellent graft and patients survival. Conclusion FK506 and CsA are safe and effective long term maintenance immunosuppressive agents in organ transplantation with wonderful prospect.
OBJECTIVE To investigate the mechanism of xenotransplantation rejection and the interaction between the immunocytes. METHODS: This review concluded the research achievements and new advances in xenotransplantation based on the relevant experimental data. RESULTS: Transgenic pig technology and novel immunosuppressants were applied to suppress hyperacute rejection and acute vascular rejection respectively. Modulation of T cell and antigen presenting cells and induction of tolerance were taken for the prevention of acute cellular rejection. CONCLUSION: In general, the technology of transgenic pig is relatively mature and effective. The mechanism and prevention of acute vascular rejection and acute cellular rejection should be further investigated.
【Abstract】Objective This study was conducted to build experimental model of orthotopic liver transplantation in rat (ROLT) with the character of acute rejection; and to study the effect of cytotoxic T lymphocyte antigen 4 immunoglobulin G (CTLA4Ig) on prevention of rejection and the induction of immune tolerance of ROLT. Methods Build model of Wistar→SD ROLT(performed by the two cuff method) with character of acute rejection.Recipients were injected with CTLA4Ig 75 μg per ROLT into abdominal cavity after 2 days of operation. Contrast was made with no treatment group, the clinical characters, the liver function, the transplantated liver pathologic character and the concentrations of TNFα in serum were observed and measured on postoperative day 7. In treatment group, all above observation were done on postoperative month 4. Above all, determination of the effect of CTLA4Ig on preventing acute rejection and inducing tolerance in ROLT was observed.Results ①Recipients (no treatment group) died one by one within 6th～14th days; pathologic character of rejection in transplantation liver could be found; ② In treatment group, on postoperative day 7 and month 4, no clinical rejection character and no pathologic character of rejection in transplantation liver were found and serum concentration of cytokins related to TNFα found lower than that of contrast group(P＜0.05), and serum concentration of ALT、AST、TBIL、DBIL found lower too(P＜0.05); But serum concentration of TP and Alb was found higher than that of contrast group(P＜0.05). Conclusion ① CTLA4Ig treatment alone inhibits the rejection responce in ROLT. ② CTLA4Ig treatment can Prevent rejection and induce immune tolerance in ROLT model with characters of acute rejection; the serum concentration of cytokins related to TNFα can probably be used as evaluation standard of rejection in ROLT rejection.
【Abstract】ObjectiveTo explore the effects of p38 mitogenactivated protein kinase (MAPK) on apoptosis of small intestinal epithelial cells after transplantation in rats. MethodsSmall intestinal transplantation was performed in SD and Wistar rats. The recipients were divided into three groups: isograft group (Wistar→Wistar group), allograft group (SD→Wistar group) and allograft+cyclosporine A group (SD→Wistar+CsA group). The grafts were harvested on day 1, 3, 5 and 7 after operation. All graft samples were subjected to histological examination. The apoptosis of graft epithelial cells was detected by TUNEL method. p38 MAPK was measured by Westernblotting method and serum TNFα was determined by ELISA. ResultsMild, moderate and severe rejection reaction occurred in the SD→Wistar group, it was showed that the number of apoptotic cells increased with the severity of the rejection reaction by TUNEL. In SD→Wistar group, the numbers of apoptotic cells were significantly higher than those of the other two groups （P＜0.01）. The severity of rejection reaction in SD→Wistar+CsA group was less than that of SD→Wistar group and the number of apoptotic cells increased with the severity of the rejection reaction (P＜0.01). The level of serum TNFα varied with the apoptotic degree of small intestinal epithelial cells in SD→Wistar group and SD→Wistar+CsA group （P＜0.01）. The expression of p38 MAPK increased with the number of the apoptotic cells in SD→Wistar group and SD→Wistar+CsA group （P＜0.01）, but there was no evident change in Wistar→Wistar group （Pgt;0.05）. The expression of p38 MAPK and the level of serum TNFα were positively correlated with apoptosis in small intestinal rejection after transplantation （r=0.875， P＜0.01； r=0.837， P＜0.01）. p38 MAPK and TNFα were also positively correlated （r=0.826，P＜0.01）. ConclusionApoptosis plays an important role in small intestinal rejection. p38 MAPK is involved in apoptosis and is an important regulator in signal pathway of cell apoptosis.
Objective To investigate the effect of nidus vespae on lymphocyte blastisation in mixed culture system of lymphocyte and pancreatic islet. Methods Solution of nidus vespae was extracted with ethanol from its herb. Rat lymphocyte and pig pancreatic islet were isolated and then were mixed together and cultured in incubators of 37 ℃ (concentration in volume: 5%CO2). Three different concentrations of extracted solution of nidus vespae （experimental group Ⅰ: 4.0 g/ml, group Ⅱ: 0.4 g/ml, group Ⅲ: 0.2 g/ml） were added to the mixed culture system of lymphocyte, respectively. Radioactive nuclide counts per minute were measured by 3H-thymdine test in order to examine the role of nidus vespae in inhibiting blatisation of lymphocyte, and the results were also compared with control group and CsA group, respectively. Results The counts were all reduced significantly (P＜0.001) in 3 experimental groups compared with control group (group Ⅰ 45.3%, group Ⅱ 29.6%and group Ⅲ 9.2%). It also showed that the inhibitory effect became ber in higher concentration but still weaker than that in CsA group (80.7%). Conclusion Nidus vespae could inhibit the blastisation of lymphocyte in mixed culture system of lymphocyte and pancreatic islet, and the effect increased as the the concentration increased, which may suggest that nidus vespae could suppress the rejection induced by T cells.
Objective To investigate the roles of cell apoptosis and the gene expressions of Fas, FasL, bcl-2 and bax in acute rejection of pancreaticoduodenal transplantation and to evaluate the function of duodenum biopsy for early detection of rejection in rats. Methods Wistar and SD rats were divided into two groups: ①Wistar rats that underwent allogenic pancreaticoduodenal transplantation from the organs of SD rats; ②Wistar rats that received homogenic transplantation. The grafts were then harvested on day 3, 5 and 7 after the transplantation, and all graft samples were observed with HE staining and TUNEL was also used to detect apoptotic cells. The expressions of Fas, FasL, bcl-2 and bax were measured by immunochemical method. According to Nakhleh’s score, pathologic features of transplanted pancreas and duodenum were ranged from one to three scores in order. Results The percentage of same or different scores between the pathological scores of pancreas and duodenum in allogenic pancreaticoduodenal transplantation group were 61.1% (11/18) and 38.9% (7/18) respectively, and there were 6 specimens of pancreatic tissue got higher scores with only one higher score for duodenum. There were significant differences of histopathologic rejection scores and apoptotic indices between the two groups, respectively (P＜0.05， P＜0.01). Apoptotic indices of pancreas and duodenum both showed positive correlations with histopathologic rejection scores (r=0.965， P＜0.01; r=0.942, P＜0.01). The rejection score and apoptotic index elevated, the expression of FasL increased, bcl-2 decreased, and Fas and bax changed over time after operation. Conclusion Apoptosis maybe significantly positive correlated with the degrees of damage of the acute pancreaticoduodenal allograft rejection, and the apoptotic index maybe valuable to estimate the damage. FasL and bcl-2 were significantly related to the impairment of acute pancreatic allograft rejection as well. Duodenum biopsy may contribute to the early diagnosis of the rejecting transplanted tissues.