Differential rates of ischemic cholangiopathy and graft survival associated with induction therapy in DCD liver transplantation.

Transplantation utilizing donation after circulatory death (DCD) donors is associated with ischemic cholangiopathy (IC) and graft loss. The University of Washington (UW) DCD experience totals 89 DCD liver transplants performed between 2003 and 2011. Overall outcome after DCD liver transplantation at UW demonstrates Kaplan-Meier estimated 5-year patient and graft survival rates of 81.6% and 75.6%, respectively, with the great majority of patient and graft losses occurring in the first-year posttransplant from IC. Our program has almost exclusively utilized either anti-thymocyte globulin (ATG) or basiliximab induction (86/89) for DCD liver transplantations. Analysis of the differential effect of induction agent on graft survival demonstrated graft survival of 96.9% at 1 year for ATG versus 75.9% for basiliximab (p = 0.013). The improved survival did not appear to be from a lower rate of rejection (21.9% vs. 22.2%) but rather a differential rate of IC, 35.2% for basiliximab versus 12.5% for ATG (p = 0.011). Multivariable analysis demonstrated induction agent to be independently associated with graft survival and IC free graft survival when analyzed against variables including donor age, fWIT, donor cold ischemia time and transplant era.

Successful combined liver/kidney transplantation from a donor with Pompe disease.

Pompe disease results from inherited deficiency of the enzyme acid alpha-glucosidase resulting in lysosomal accumulation of glycogen primarily in skeletal muscle. Reported is the first case in which a donor with late onset Pompe disease (LOPD) was successfully used for deceased donor liver and kidney transplantation. This case demonstrates co-operative transplant surgery and genetic medicine evaluation and risk estimation for donors with inherited metabolic disorders some of which may be suitable for donation of selected organs for transplantation.

Risk stratification of kidneys from donation after cardiac death donors and the utility of machine perfusion.

There has been a dramatic increase in the utilization of kidneys from donors after cardiac death (DCD). While these organs represent an opportunity to expand the donor pool, the assessment of risk and optimal perioperative management remains unclear. Our primary aim was to identify risk factors for objective outcomes, and secondarily, we sought to determine what impact pulsatile machine perfusion (PMP) had on these outcomes. From 1993 to November 2008, 6057 DCD kidney transplants were reported to the Organ Procurement and Transplantation Network database, with complete endpoints for delayed graft function (DGF) and graft survival (GS). Risk factors were identified using a multivariable regression analysis adjusted for recipient factors. Age (50 yr) [OR 1.81, p < 0.0001] and cold ischemia time (CIT) (>30 h) [OR 3.22, p < 0.0001] were the strongest predictors of DGF. The use of PMP decreased the incidence of DGF only when donor age was >60 yr and improved long-term graft survival when donor age was >50 yr. Donor warm ischemia time >20 min was also found to correlate with increased DGF. While the incidence of DGF in DCD kidneys is significantly higher, the only factors the transplant surgeon can control are CIT and the use of PMP. The data suggest that the use of PMP in DCD kidneys <50 yr old provides little clinical benefit and may increase CIT.

Redox gene therapy for ischemia/reperfusion injury of the liver reduces AP1 and NF-kappaB activation.

Liver transplantation is the only therapeutic strategy for many inherited and acquired diseases. The formation of reactive oxygen species following ischemia/reperfusion is a cause of hepatocellular injury during transplantation. This report describes the therapeutic application of mitochondrial superoxide dismutase gene transfer to the liver for acute ischemia/reperfusion injury. Recombinant adenoviral expression of mitochondrial superoxide dismutase in mouse liver prior to lobar ischemia/reperfusion significantly reduced acute liver damage and associated redox activation of both NF-kappaB and AP1. These immediate early transcription factors represent common pathways by which cells respond to environmental stress. This work provides the foundation for redox-mediated gene therapies directed at ameliorating ischemia/reperfusion injury and associated acute rejection in orthotopic liver transplantation.

D-MELD, a simple predictor of post liver transplant mortality for optimization of donor/recipient matching.

Numerous donor and recipient risk factors interact to influence the probability of survival after liver transplantation. We developed a statistic, D-MELD, the product of donor age and preoperative MELD, calculated from laboratory values. Using the UNOS STAR national transplant data base, we analyzed survival for first liver transplant recipients with chronic liver failure from deceased after brain death donors. Preoperative D-MELD score effectively stratified posttransplant survival. Using a cutoff D-MELD score of 1600, we defined a subgroup of donor-recipient matches with significantly poorer short- and long-term outcomes as measured by survival and length of stay (LOS). Avoidance of D-MELD scores above 1600 improved results for subgroups of high-risk patients with donor age >/=60 and those with preoperative MELD >/=30. D-MELD >/=1600 accurately predicted worse outcome in recipients with and without hepatitis C. There is significant regional variation in average D-MELD scores at transplant, however, regions with larger numbers of high D-MELD matches do not have higher survival rates. D-MELD is a simple, highly predictive tool for estimating outcomes after liver transplantation. This statistic could assist surgeons and their patients in making organ acceptance decisions. Applying D-MELD to liver allocation could eliminate many donor/recipient matches likely to have inferior outcome.

CD4(+) T-lymphocytes mediate ischemia/reperfusion-induced inflammatory responses in mouse liver.

The success of orthotopic liver transplantation is dependent on multiple factors including MHC tissue compatibility and ischemic/reperfusion injury. Ischemic/reperfusion (I/R) injury in the liver occurs in a biphasic pattern consisting of both acute phase (oxygen free radical mediated) and subacute phase (neutrophil-mediated) damage. Although numerous studies have given insights into the process of neutrophil recruitment after I/R injury to the liver, the exact mechanism that initiates this subacute response remains undefined. Using a T cell-deficient mouse model, we present data that suggests that T-lymphocytes are key mediators of subacute neutrophil inflammatory responses in the liver after ischemia and reperfusion. To this end, using a partial lobar liver ischemia model, we compared the extent of reperfusion injury between immune competent BALB/c and athymic nu/nu mice. Studies evaluating the extent of liver damage as measured by serum transaminases (GPT) demonstrate similar acute (3-6 h) post-I/R responses in these two mouse models. In contrast, the subacute phase (16-20 h) of liver injury, as measured by both serum GPT levels and percent hepatocellular necrosis, was dramatically reduced in T cell-deficient mice as compared with those with an intact immune system. This reduction in liver injury seen in nu/nu mice was associated with a 10-fold reduction in hepatic neutrophil infiltration. Adoptive transfer of T cell-enriched splenocytes from immune competent mice was capable of reconstituting the neutrophil-mediated subacute inflammatory response within T cell-deficient nu/nu mice. Furthermore, in vivo antibody depletion of CD4(+) T-lymphocytes in immune competent mice resulted in a reduction of subacute phase injury and inflammation as measured by serum GPT levels and neutrophil infiltration. In contrast, depletion of CD8(+) T-lymphocytes had no effect on these indexes of subacute inflammation. Kinetic analysis of T cell infiltration in the livers of BALB/c mice demonstrated a fivefold increase in the number of hepatic CD4(+) T-lymphocytes within the first hour of reperfusion with no significant change in the number of CD8(+) T-lymphocytes. In summary, these results implicate CD4(+) T-lymphocytes as key regulators in initiating I/R-induced inflammatory responses in the liver. Such findings have implications for therapy directed at the early events in this inflammatory cascade that may prove useful in liver transplantation.

Serum alkaline phosphatase and bilirubin are early surrogate markers for ischemic cholangiopathy and graft failure in liver transplantation from donation after circulatory death.

Liver transplantation with the use of donation after circulatory death (DCD) is associated with ischemic cholangiopathy (IC) often leading to graft loss. We hypothesized that serial postoperative analysis of alkaline phosphatase and bilirubin might identify patients who would later on develop ischemic cholangiopathy and/or graft loss, allowing early recognition and potentially retransplantation. The University of Washington DCD experience totals 89 DCD liver transplantations performed from 2003 to 2011 with Kaplan-Meier estimated 5-year patient and graft survival rates of 81.6% and 75.6%, respectively; 84/89 patients transplanted with DCD livers lived ≥ 60 days after transplantation and were analyzed. Serum bilirubin and alkaline phosphatase levels at 1 week, 2 week, 1 month, and 2 months after transplantation were analyzed. Two-month serum bilirubin and alkaline phosphatase proved to have the strongest associations with development of IC and graft failure. Two-month alkaline phosphatase of <100 U/L had a negative predictive value of 97% for development of IC. Two-month alkaline phosphatase demonstrated an inflection starting at >300 U/L strongly associated with development of IC (P < .0001). Serum bilirubin at 2 months was most strongly associated with graft failure within the 1st year with a strong inflection point at 2.5 mg/dL (P = .0001). All jaundiced recipients at 60 days after transplantation (bilirubin >2.5 mg/dL) developed graft failure within the 1st year (P < .0001). Use of these early surrogate markers could facilitate prioritization and early retransplantation for DCD liver recipients with allografts destined for failure.

The use of hepatitis B core antibody-positive donor livers does not appear to have a deleterious effect on graft survival in liver transplantation for hepatitis C.

INTRODUCTION: The use of hepatitis B core antibody-positive donor livers (HBcAb(+)) has steadily increased. According to a recent multivariate analysis of United Network for Organ Sharing (UNOS) data, there was no significant increase in the risk of using these donors. The increased risk among the hepatitis C virus (HCV)-positive subgroup noted in a univariate model disappeared upon multivariate analysis. However, deeper scrutiny may show that HCV-positive recipients may be at increased risk with HBcAb(+) donor livers, as they require simultaneous treatment with two antiviral regimens there may be deleterious interactions between the two viruses. Thus, the issue of HBcAb(+) donors for HCV-positive recipients merits more detailed analysis. METHODS: Using UNOS registry data of all liver transplantations performed during the Model for End-Stage Liver Disease era from February 2002 through November 2007, we analyzed graft survival using Kaplan-Meier and Cox regression analyses. RESULTS: Of the 12,543 HCV-positive recipients, 2,543 received HBcAb(-) livers and 853 received HBcAb(+) livers. While Kaplan-Meier analysis showed significantly lower graft survival among HCV-negative recipients of HBcAb(+) livers (P = .0001), there was no significant effect on graft survival among the HCV-positive population (P = .2). To detect an early effect in HCV-positive recipients, we examined 1-year graft survival, observing no significant difference (P = .3). To exclude a possible late effect, we examined graft survival in the HCV-positive population conditional upon surviving at least 1 year after transplantation; no significant difference was observed (P = .6). The elimination of potentially confounding codiagnoses, such as hepatitis B virus, alcoholism, acute graft failure, and hepatocellular cancer did not alter the findings. On univariate analysis, the lack of a significant effect persisted among the HCV population. However, the significant effect observed in the univariate model for the HCV-negative population became insignificant when combined with other risk factors in the multivariate model. CONCLUSION: The use of HBcAb(+) livers in recipients with HCV did not appear to have a significant impact on graft survival.

iNOS expression in dystrophinopathies can be reduced by somatic gene transfer of dystrophin or utrophin.

BACKGROUND: Nitric oxide (NO) is an inorganic gas produced by a family of NO synthase (NOS) proteins. The presence and the distribution of inducible-NOS (NOS II or iNOS), and NADPH-diaphorase (NADPH-d), a marker for NOS catalytic activity, were determined in muscle sections from control, DMD, and BMD patients. MATERIALS AND METHODS: NADPH-d reactivity, iNOS- and nNOS (NOS I)-immunolocalization were studied in muscles from mdx mice before and after somatic gene transfer of dystrophin or utrophin. RESULTS: In control patients, few fibers (<2%) demonstrated focal accumulation of iNOS in sarcolemma. In DMD patients, a strong iNOS immunoreactivity was observed in some necrotic muscle fibers as well as in some mononuclear cells, and regenerating muscle fibers had diffusely positive iNOS immunoreactivity. In DMD patients, NADPH-d reactivity was increased and mainly localized in regenerating muscle fibers. In mdx mice quadriceps, iNOS expression was mainly observed in regenerating muscle fibers, but not prior to 4 weeks postnatal, and was still present 8 weeks after birth. The expression of dystrophin and the overexpression of utrophin using adenovirus-mediated constructs reduced the number of iNOS-positive fibers in mdx quadriceps muscles. The correction of some pathology in mdx by dystrophin expression or utrophin overexpression was independent of the presence of nNOS. CONCLUSIONS: These results suggest that iNOS could play a role in the physiopathology of DMD and that the abnormal expression of iNOS could be corrected by gene therapy.

Ischemia/reperfusion injury in the liver of BALB/c mice activates AP-1 and nuclear factor kappaB independently of IkappaB degradation.

For many inherited and acquired hepatic diseases, liver transplantation is the only possible therapeutic strategy. Ischemia/reperfusion (I/R) damage to donor tissue is thought to be one component that may play a role in the decline of posttransplant tissue function and ultimately rejection. The transcription factors, AP-1 and nuclear factor kappaB (NF-kappaB), play important roles in the acute cellular responses to tissue damage, as well as the inflammatory phase following I/R. We have found that the DNA binding activity of AP-1 was dramatically increased following warm ischemia at 1 to 3 hours postreperfusion. Induced DNA binding activity was composed of predominately c-Jun and JunD hetero- and homodimers as determined by electrophoretic mobility supershift assays. This increase in AP-1 activity occurred in the absence of significant changes in the steady-state protein levels of c-Jun and JunB. Maximal activation of Jun amino-terminal kinase ( JNK) occurred within the 25 to 30 minutes postreperfusion, just before the peak in AP-1 DNA binding. These findings suggest that phosphorylation may play an important role in regulating AP-1 transcriptional complexes. Furthermore, JunD protein levels slightly increased at 3 hours postreperfusion, concordant with changes in AP-1 DNA binding activity. The activation of NF-kappaB at 1 hour postreperfusion was independent of proteolytic degradation of IkappaB- or IkappaB-beta. This activation of NF-kappaB DNA binding activity in the nucleus was preceded by an increase in tyrosine phosphorylation of IkappaB-. These studies suggest that JNK, IkappaB tyrosine kinase, and JunD are potential targets for therapeutic intervention during liver I/R injury.