[The protective effects on allografts of adeno-associated heme-oxygenase-1 gene therapy against chronic rejection injury].

OBJECTIVE: To investigate the protective effects on allografts and the possible mechanism of adeno-associated heme-oxygenase-1 (AdHO-1) gene therapy against chronic rejection injury. METHODS: Ex vivo AdHO-1 gene therapy was performed in vascular and renal transplantation models. The structure and function, the expression of therapeutic genes and proteins, and the immune modulation were analyzed. RESULTS: AdHO-1 gene therapy protected renal transplant against chronic rejection, but the effect was not as remarkable as that in vascular transplant. The transfected empty vehicle aggravated chronic rejection damage in renal transplantation. AdHO-1 decreased the infiltration of macrophages and CD4(+) T cells. CONCLUSIONS: AdHO-1 gene therapy can lessen damage of chronic rejection in allografts. It plays roles by protecting transplants, down-regulating immune response and inducing immune deviation.

[Effect of mono and combination therapy with FTY720 and ICAM-1 mAb for mouse-to-rat cardiac xenotransplantation].

OBJECTIVE: To observe the effect of FTY720 and ICAM-1 mAb mono and combination therapy in mouse-to-rat cardiac xenotransplantation. METHODS: Cardiac xenotransplantation was performed in abdominal site with micro-surgical technique. Recipients with xenografts were treated with different doses of FTY720 and/or ICAM-1 mAb. Graft survival, histopathology, infiltration of CD4+, and CD8+ T cells and levels of serum IL-2, IFN-gamma, IL-4, and IgM were investigated. RESULTS: Survival time of xenografts was (2.75+/- 0.43)d in the controls, survival of grafts treated with ICAM-1 mAb did not significantly improve. Treatment with large dose FTY720 led to a survival of (4.25+/- 0.71)d (P<0.01). Combination therapy with large dose FTY720 and ICAM-1 mAb achieved a significant prolongation of graft survival with (10.25+/- 2.12)d (P<0.01). Levels of serum IL-2, IFN-gamma and rat-anti-mouse IgM decreased in the combined therapy group. Pathologic lesion and infiltration of T cells in xenografts showed mitigated in the large dose combined therapy group. There was a significant negative correlation between the antibody level and the graft survival time (R=-0.754, P<0.01). CONCLUSION: The combined therapy of FTY720 and ICAM-1 mAb can achieve a significant effect in the prolongation of heart xenograft survival and inhibition of xenoantibodies.

[Immune tolerance induced by combined heart-thymus transplantation for heart allograft in rats].

OBJECTIVE: To explore the role of combined heart-thymus transplantation for heart allograft in rats. METHODS: Vascularized heart-thymus combined transplantation was performed with microsurgical technique. Graft survival, histopathology, infiltration of CD4+, CD8+ T cells, level and mRNA expressions of IL-2 and IL-4 in the serum and cardiac grafts were investigated. RESULTS: Heart allograft in the controls had a survival time of (6.0+/-0.76) d. heart-thymus combined transplantation in non-thymectomized rats had a survival time of (6.88+/-0.64)d (P<0.05). Heart-thymus combined transplantation in thymectomized rats led to an evident survival time of (14.13+/-5.82)d (P<0.01) for cardiac graft, which further obtained long term survival after short course of treatment with cyclosporine. Pathologic lesion and infiltration of CD4+ and CD8+ T cells in cardiac grafts showed mitigated in the long term survival group. IL-2 level in the serum and cardiac grafts maintained low level in the long term survival group, whereas IL-4 maintained high level. CONCLUSION: Whether thymectomized or not in recipient rats, heart-thymus combined transplantation has a positive effect to protect cardiac graft. Furthermore, in thymectomized rats heart-thymus combined transplantation may lead to evident survival prolongation of the heart grafts, which induces immune tolerance in short course of treatment with cyclosporine.

[Immune tolerance induced by combined heart-thymus transplantation with intrathymic inoculation of thymocytes in rats].

OBJECTIVE: To explore the role of allo heart and thymus transplantation by intrathymic inoculation of thymocytes. METHODS: Wistar recipients were given intrathymic injection of allo thymocytes (2 x 10(7)) 14 days before the heart and/or thymus transplantation. Graft survival, histopathology, levels and mRNA expressions of IL-2, IL-4 in serum and cardiac-grafts were investigated. RESULTS: Heart transplantation and heart-thymus composite transplantation with the treatment of CysA for 7 or 14 days prolonged graft survival. Heart transplantation and heart-thymus composite transplantation with intrathymic thymocytes injection induced the long-term survival of allo-grafts transiently immunosuppressed with CysA; IL-4 maintained at high levels but IL-2 kept at low levels in grafts in long-term survivals. CONCLUSION: Intrathymic inoculation of allo thymoctyes can induce immune tolerance for both cardiac transplantation and heart-thymus combined transplantation in rats. Thymus graft may play a role in the induction and maintenance of central tolerance.

[Effect of cyclosporine and simulect mono and combination therapy on cardiac allo-transplantation in rats].

OBJECTIVE: To observe the effect of cyclosporine and simulect mono or combination therapy on cardiac allo-transplantation in rats. METHODS: Recipients with allografts were treated with different doses of cyclosporine and/or simulect after cardiac allo-transplantation. Graft survival time was observed; the histopathological examination of graft tissues was performed; and levels of serum IL-2 and IL-4 were determined. RESULTS: Mono or combination therapy with cyclosporine and/or simulect increased the survival of cardiac allografts. With the prolongation of survival time of the grafts, the rejection of grafts was moderated. The serum IL-2 level increased in acute rejected grafts; the serum IL-4 level increased evidently in long survival grafts. CONCLUSION: Cyclosporine and simulect have an effect in the prolongation of cardiac allograft survival in rats, and the combination therapy shows an evident synergistic effect.

[Risk factors of acute rejection in sensitized kidney transplant recipients].

OBJECTIVE: To identify the risk factors of acute rejection in sensitized recipients undergoing kidney transplantation. METHODS: The clinical data of 102 sensitized kidney transplant recipients were retrospectively analyzed to evaluate the incidence of acute rejection in relation to panel reactive antibodies (PRA), amino acid residual match, postoperative elevation of PRA level and cytokine genotypes. RESULTS: During the follow-up, acute rejection occurred in totally 33 patients, and the incidence was higher in the recipients with high tumor necrosis factor (TNF)-alpha or high interleukin (IL)-10 producer genotype than in those with low TNF-alpha or low/intermediate IL-10 producer genotype (53.1%, 55.0% vs 22.8%, 20.9%, P(18)0.01 respectively). Acute rejection was even more frequent in the recipients with both high TNF-alpha and high/intermediate IL-10 producer genotypes than in those with low TNF-alpha and IL-10 producer genotype (66.7% vs 10.2%, P<0.01). No relations were found between TGF-beta1, IL-6, IFN-gamma gene polymorphisms and the incidence of acute rejection. The incidence in the recipients with PRA level of more than 40% was also higher than those with lower PRA level (<20%, 53.3% vs 22.7%, P<0.05), and the amino acid residual mismatch with 3-4 MM was responsible for a higher incidence in comparison with a mismatch with 0-1 MM (75.0% vs 24.1%, P<0.01). Postoperative elevation of PRA level also increased the risk of acute rejection (45.4% vs 22.4%, P<0.01). CONCLUSION: TNF-alpha, IL-10 gene polymorphism, PRA, amino acid residual mismatch, and increased postoperative PRA level may significantly influence acute rejection in sensitized kidney transplantation recipient, and preoperative evaluation of these factors may benefit the designing of immunosuppressive protocols for these patients.

Etiological factors for subphrenic infection after hepatectomy for patients with hepatic malignancy.

BACKGROUND: This study was to clarify the high risk factors for subphrenic infection (SI) after liver resection for patients with hepatic malignancy. METHODS: Three hundred and sixty-eight patients who had undergone hepatectomy from January 1985 through June 2002 were randomly divided into 2 groups according to resection of liver parenchyma, hepatic cirrhosis, primary liver cancer, intraoperative blood loss, and subphrenic drainage. The chi-square was used for statistical analysis. RESULTS: Thirteen patients (3.53%) of the 368 patients had SI. The high-risk factors for SI after hepatectomy were related to resection of liver parenchyma and hepatic cirrhosis; but the course or stage of primary liver cancer was not related to the incidence of SI. Intraoperative blood loss of over 1500 ml was found to be a significant risk factor for postoperative SI. Adequate drainage of the subdiaphragm and the raw surface of the liver after operation was essential to decreasing SI after liver resection. CONCLUSION: Inadequate subphrenic drainage may largely contribute to SI in patients with hepatic malignancy undergoing hepatectomy apart from other factors. Comprehensive measures should be taken to prevent the infection after hepatectomy.

Apoptosis and proliferation of intrahepatic bile duct after ischemia-reperfusion injury.

BACKGROUND: In orthotopic liver transplantation, ischemic-reperfusion is one of the most important factors that cause the incidence of biliary compliance. The aim of this study was to investigate the effects of ischemia reperfusion on epithelial cells apoptosis and proliferation of intrahepatic bile duct (IBD) (>20 microm). METHODS: 30-minute warm ischemia was applied to rat livers respectively, and experiment was performed on days 2, 7, 14, 28 after reperfusion. Apoptosis was determined in situ by morphology and TUNEL, and cholangiocyte proliferation was evaluated in situ by morphometry of liver sections stained for cytokeratin-19 (CK-19) and by proliferating cellular nuclear antigen staining in liver sections. RESULTS: Two days after ischemia reperfusion, apoptosis of cells was observed in large intrahepatic bile ducts (>20 microm) (5.6%+/-1.2%), but the number of large intrahepatic bile ducts reduced (0.32+/-0.06). Seven days after ischemia reperfusion, the apoptosis index of cholangiocytes decreased to 1.2%+/-0.3%, and the number of intrahepatic bile ducts began to proliferate and returned to nearly normal on day 28. CONCLUSION: Ischemia reperfusion causes a decrease in the number of intrahepatic bile ducts (>20 microm) as a result of a higher rate of apoptosis and absence of initial proliferation.

gamma-hydroxybutyrate protects the liver from warm ischemia-reperfusion injury in rat.

BACKGROUND: Ischemia-reperfusion (I/R) syndrome remains an important clinical consideration in hepatic surgery, hemorrhagic shock, and liver transplantation. gamma-hydroxybutyrate (GHB) has been reported to exert protective effects against ischemia-reperfusion injury to various organs. To investigate whether GHB protects the liver from warm ischemia-reperfusion injury, we performed this study in rats. METHODS: Thirty male Wistar rats were randomly divided into a sham-operation group, a control group,and three I/R groups pretreated with GHB, GHB plus naloxone or naloxone. After 30 minutes of partial ischemia, followed by 60 minutes of reperfusion in the liver, histomorphological and enzymological changes, lipid peroxidation, apoptosis, and the plasma level of endothelin-1 were observed. RESULTS: I/R increased the serum levels of alanine aminotransferase, aspartate aminotransferase and lactate dehydrogenase and the plasma level of endothelin-1 significantly (P<0.01), in addition to increase of apoptotic index (AI) from 0.28%+/-0.25% to 17.68%+/-1.91%. The levels of hepatic malondialdehyde were markedly increased, whereas the activities of superoxide dismutase were markedly decreased. GHB pretreatment prevented the liver from warm ischemia-reperfusion injury significantly, but naloxone partially blocked this effect. CONCLUSION: GHB may significantly protect the liver from hepatic warm ischemia-reperfusion injury via several different mechanisms.

Risk factors for graft survival in sensitized recipients of kidney transplantation.

OBJECTIVE: To investigate the independent prognostic factors for graft survival in sensitized recipients undergoing kidney transplantation, so as to identify the individuals at high risk of graft loss before transplantation. METHODS: A retrospective investigation was conducted in 102 sensitized kidney transplant recipients and 31 relative variables were analyzed with SPSS10.0 software. Using log-rank method, the influence of these variables on short- and long-term graft survivals was evaluated, and Kaplan-Meier analysis was performed to estimate the 1-, 3- and 5-year graft survival rates and half-life. Proportional hazards regression analysis (Cox model) was used to assess the relative risks of the potential variables. RESULTS: In the recipients with a mean half-life of 8.9 years, the 1-, 3- and 5-year graft survival rates were 90%, 85%, and 75%, respectively. By log-rank analysis, the factors affecting short- and long-term graft survivals were identified, namely the recipient age, times of transplantation, levels of panel reactive antibody and the post-operative anti-HLA-IgG antibody, HLA mismatch, renal function, time needing for graft function recovery, presence of acute rejection, delay of graft function recovery and infection, which affected the graft survival demonstrated by Cox model multivariate analysis. CONCLUSION: High-quality donor kidney and minimization of the risk factors for graft survival may insure successful kidney transplantation in sensitized recipients.

[Influence of p16 gene on the biological behavior of human hepatocellular carcinoma].

BACKGROUND & OBJECTIVE: Inactivation of the tumor suppressor gene p16INK4a is one of the most common genetic alterations in human hepatocellular carcinomas (HCC), making it an ideal target gene for treatment of HCC. The objective of this study was to investigate the influence of wild p16 gene on the biological behavior of HCC. METHODS: HCC cell strains SNU-449 (loss of p16 protein expression) and HepG2.2. 15 (positive p16 protein expression) were respectively infected by a retrovirus expression vector of p16 gene (pcLXSN-p16). The stable p16 protein expression cell strains were selected. The biological behaviors of the p16 gene transfected HCC cells were observed. RESULTS: SNU-449 with negative p16 protein expression demonstrated that pcLXSN-p16 treatment significantly inhibited cell growth (the amount of cells at G0-G1 phase increased). However, there was no treatment effect when pcLXSN-p16 was transfected in HepG2.2. 15 which has positive p16 protein expression. Subsequent study in a nude mouse model demonstrated that the p16 gene transfected SNU-449 had a lower succeeding rate of first time establishment of tumors and grew more slowly in the nude mice as compared with non-transfected SNU-449. Moreover, the nude mice inoculated with transfected SNU-449 had a longer survival time than those inoculated with non-transfected SNU-449. CONCLUSION: The transfer of wild p16 gene can inhibit the proliferation and reduce the invasion ability of HCC cells with p16 negative expression, but can not affect the HCC cells with p16 positive expression.

Effects of p16 gene on biological behaviours in hepatocellular carcinoma cells.

AIM: To investigate the effects of p16 gene on biological behaviours in hepatocellular carcinoma cells. METHODS: HCC cell lines SNU-449 and HepG2.2.15 were infected respectively by a replication defective, recombinant retrovirus capable of producing a high level of p16 protein expression (pCLXSN-p16). G418 resistant stable P16 protein expression cell lines were selected. And the biological behaviours of the p16 gene transfected HCC cells were observed. RESULTS: Initial in vitro experiments in HCC cell line SNU-449 with loss of p16 protein expression demonstrated the pCLXSN-p16 treatment significantly inhibited cell growth. But there was no treatment effect when the pCLXSN-p16 was used in another HCC cell line HepG2.2.15 which has positive p16 protein expression. Subsequent study in a nude mouse model demonstrated that the p16 gene transfected SNU-449 had a lower succeeding rate in the first time establishment of tumors and grew more slowly in the nude mice when compared with non-transfected SNU-449. Moreover, the nude mice inoculated with transfected SNU-449 had a longer surviving time than those inoculated with non-transfected SNU-449. CONCLUSION: Our results show that the p16INK4a gene transfer can inhibit the proliferation and reduce the invasion ability of hepatocellular carcinoma.

Combined small bowel and reduced auxiliary liver transplantation: case report.

AIM: To present a case of combined small bowel and reduced auxiliary liver transplantation. METHODS: A 55-year-old patient with short bowel syndrome and TPN-related liver dysfunction received small bowel transplantation combined with a reduced auxiliary liver graft. A liver was added to restore the patient's liver function and to protect the intestinal allograft from rejection. His own liver was not removed. RESULTS: Without donor pretreatment and by conventional immunosuppresive therapy following transplantation, the patient experienced had only one episode of mild intestinal rejection, which was easily reversed by treatment with Methylprednisolone. No liver rejection occurred. Unfortunately, the patient died of heart and lung failure 30d after transplantation, despite successful graft replacement. Histopathologic examination of specimens after death demonstrated normal structure in both intestinal and liver grafts. CONCLUSION: The auxiliary liver graft might play a role in preventing intestinal allograft rejection. However, the observation period in this case is short. Further study is needed to determine the risks, effect on the protecting the small-bowel from rejection, and feasibility of general application of this procedure.

Acute respiratory distress syndrome after liver transplantation: etiology, prevention and management.

OBJECTIVE: To study the etiology, prevention and management of acute respiratory distress syndrome (ARDS) after liver transplantation. METHODS: The clinical data of 104 patients with end-stage liver diseases who had had liver transplantations were retrospectively reviewed. RESULTS: Seventeen patients (16.3%, 17/104) altogether were diagnosed as having ARDS after liver transplantation. Ten of them developed ARDS within 24 hours, of whom 1 died during the operation, and 7 developed ARDS 3 or 4 days after they were extubated and when methylprednisolone was tapered. Fourteen of the 17 ARDS patients (14/17) were found to have overloaded crystalloid infusion, massive transfusion of blood or blood products such as plasma, platelets, in addition to a prolonged surgical time secondary to serious bleeding during the diseased liver removal without evidence of active infection. One was found to have serious systemic infection and operatively disseminated intravascular coagulation. Four of the recipients developed ARDS suddenly when intravenous cyclosporine was given on the 3rd day after operation. One patient of the 4 had all of the aforementioned conditions. Two patients suffered from gastric aspiration. Five (30%, 5/17) of them survived ARDS with the combined treatment consisting of positive end-expiratory pressure mechanical ventilation suctioning as much edema fluid or sputum as possible, administration of diuretics, bolus of corticosteroids, and culture-based antibiotics. Hemeodialysis was indicated for patients with oliguric renal failure. CONCLUSIONS: ARDS is a serious multifactoral complication after liver transplantation with a high mortality and fatality. The most likely cause is fluid overload from crystalloid liquid infusion or massive transfusion. The other predisposing or contributing factors include sepsis, IV use of cyclosporine, fast tapering of corticosteroids, and gastric aspiration. Other factors such as transfusion-related acute lung injury (TRALI), and reperfusion syndrome of the newly implanted liver may also contribute. Though the treatment should primarily be supportive in nature, it is helpful to understand the predisposing and contributing factors and to aid in prevention, management and treatment.