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Background: In controlled donation after circulatory determination of death (DCD), it is common to administer premortem heparin to potential donors. This practice remains controversial because there is limited evidence for it and there is the possibility of inducing hemorrhage. To our knowledge, no previous studies have assessed the effects of heparin timing and dose on graft function., Methods: We performed a multicentre cohort study of consecutive DCD donors and the recipients of their organs. Anticoagulation administration was considered early if given near the time of withdrawal of life-sustaining measures and late if delayed until the onset of donor hypoxemia (oxygen saturation < 70%) or hypotension (systolic blood pressure < 60 mm Hg or mean blood pressure < 50 mm Hg). The anticoagulation dose was considered high if it was 300 units/kg or greater., Results: Donor anticoagulation data were available for 301 kidney, 75 liver and 46 lung recipients. Heparin was administered in 92% of cases and was most commonly withheld in donors with cerebrovascular causes of death ( p = 0.01). Administration was late in 59% and the dose was low in 27%. Among kidney recipients, there were no significant differences in need for dialysis, glomerular filtration rate over the first year after transplantation or graft survival on the basis of whether or not the donor received heparin, the timing of heparin administration or the dose of heparin. Among liver recipients, alkaline phosphatase concentrations over the first year were significantly higher among recipients who received organs from donors to whom lower doses of heparin had been administered., Conclusion: Premortem heparin is widely used in DCD cases, but there is variability in timing and dose, which was not associated with kidney outcomes in this study. Donor anticoagulation may have a greater impact in preventing biliary complications following liver transplantation., Competing Interests: Competing interests: None declared., (© 2022 CMA Impact Inc. or its licensors.)

Aim: To investigate the effect of 20-hydroxyecdysone on steroidogenic pathway genes and plasma progesterone, and its potential impact on vascular functions., Methods: Chimeric mice with humanized liver were treated with 20-hydroxyecdysone for 3 days, and hepatic steroidogenic pathway genes and plasma progesterone were measured by transcriptomics and GC-MS/MS, respectively. Direct effects on muscle and mesenteric arterioles were assessed by myography., Results: CYP17A1 was downregulated in 20-hydroxyecdysone-treated mice compared with untreated group (p = 0.04), with an insignificant increase in plasma progesterone. Progesterone caused vasorelaxation which was blocked by 60 mM KCl, but unaffected by nitric oxide synthase inhibition., Conclusion: In the short term, 20-hydroxyecdysone mediates CYP17A1 downregulation without a significant increase in plasma progesterone, which has a vasodilatory effect involving inhibition of voltage-dependent calcium channels, and the potential to enhance 20-hydroxyecdysone vasorelaxation., (© 2022 The Authors.)

Background & Aims: Association between sarcopenia and mortality in cirrhosis is well recognised; however, little is known about the clinical implications of adipose tissue radiodensity, indicative of biological features. This study aimed to determine an association between high subcutaneous adipose tissue (SAT) radiodensity and survival, compare the prevalence of high SAT radiodensity between healthy population and patients with cirrhosis, and identify an association between computed tomography (CT)-measured SAT radiodensity and histological characteristics., Methods: Adult patients with cirrhosis (n = 786) and healthy donors (n = 129) with CT images taken as part of the liver transplant (LT) assessment were included. Abdominal SAT biopsies (1-2 g) were harvested from the incision site at the time of LT from 12 patients with cirrhosis., Results: The majority of patients were male (67%) with a mean model for end-stage liver disease (MELD) score of 15 ± 8. SAT radiodensity above -83 HU in females (sub-distribution hazard ratio [sHR] 1.84, 95% CI 1.20-2.85, p  = 0.006) and higher than -74 HU in males (sHR 1.51, 95% CI 1.05-1.18, p  = 0.02) was associated with the highest mortality risk after adjusting for confounders in competing risk analysis. The frequency of high SAT radiodensity was 26% for those with cirrhosis, compared with 2% in healthy donors ( p <0.001). An inverse correlation was found between SAT radiodensity and the mean cross-sectional area of SAT adipocytes ( r  = -0.67, p  = 0.02). Shrunken, smaller adipocytes with expanded interstitial space were predominant in patients with high SAT radiodensity, whereas larger adipocytes with a thin rim of cytoplasm were observed in patients with low SAT radiodensity (744 ± 400 vs. 1,521 ± 1,035 μm 2 , p <0.001)., Conclusion: High SAT radiodensity frequently presents and is associated with a higher mortality in cirrhosis. SAT morphological rearrangement in patients with high SAT radiodensity might indicate diminished lipid stores and alterations in tissue characteristics., Lay Summary: Poor quality of subcutaneous adipose tissue (fat under the skin) is associated with higher mortality in patients with end-stage liver disease. Fat cells are smaller in patients with poor adipose tissue quality., Competing Interests: The authors declare no conflicts of interest that pertain to this work. Please refer to the accompanying ICMJE disclosure forms for further details., (© 2022 The Author(s).)

Plasma low-density lipoprotein (LDL) is primarily cleared by LDL receptor (LDLR). LDLR can be proteolytically cleaved to release its soluble ectodomain (sLDLR) into extracellular milieu. However, the proteinase responsible for LDLR cleavage is unknown. Here we report that membrane type 1-matrix metalloproteinase (MT1-MMP) co-immunoprecipitates and co-localizes with LDLR and promotes LDLR cleavage. Plasma sLDLR and cholesterol levels are reduced while hepatic LDLR is increased in mice lacking hepatic MT1-MMP. Opposite effects are observed when MT1-MMP is overexpressed. MT1-MMP overexpression significantly increases atherosclerotic lesions, while MT1-MMP knockdown significantly reduces cholesteryl ester accumulation in the aortas of apolipoprotein E (apoE) knockout mice. Furthermore, sLDLR is associated with apoB and apoE-containing lipoproteins in mouse and human plasma. Plasma levels of sLDLR are significantly increased in subjects with high plasma LDL cholesterol levels. Thus, we demonstrate that MT1-MMP promotes ectodomain shedding of hepatic LDLR, thereby regulating plasma cholesterol levels and the development of atherosclerosis.

Background: Undifferentiated embryonal cell sarcoma (UESL) of the liver is the third most common malignant liver disease of childhood presenting as a rapidly enlarging intraabdominal mass. This systematic review explores the practicality of liver transplantation as a viable option in the treatment armamentarium for locally advanced undifferentiated embryonal cell sarcoma., Methods: A systematic review of the literature was performed using Medline and Embase, from inception of databases to December 31, 2018. Keywords and MeSH headings used were embryonal sarcoma, mesenchymal sarcoma, and liver transplant. Reviews and manuscripts with incomplete data were excluded., Results: Twenty-eight patients had orthotopic liver transplantation (OLT) as a curative treatment option. The median age at presentation was 8 and 27 years in the pediatric and adult population, respectively, with a similar male to female ratio. A majority of the patients presented with abdominal pain, palpable mass, and a normal alpha-feto-protein. The median tumor size was 15 cm mainly affecting the right lobe (62%) of the liver. Eighty-two percent of the patients underwent primary OLT and 5 patients had salvage OLT. One death (3.6%) was due to initial misdiagnosis and management for hepatoblastoma. Recurrence was noted in 7.1% of the population. The median follow-up was noted to be 28.5 months. The documented survival rate post-liver transplant for UESL was 96%., Conclusions: Based on available data and the very positive results therein, liver transplantation is a practical and justifiable use of a scarce resource as a treatment option for locally unresectable, undifferentiated embryonal cell sarcoma. The authors propose (accepting existence of different proposals) neoadjuvant therapy before curative resection, and if not achievable, then liver transplantation followed by adjuvant chemotherapy is an option for suitable candidates. For recurrent tumors after surgical resection, adjuvant therapy with salvage liver transplantation is an option., Competing Interests: The authors declare no funding and conflicts of interest., (Copyright © 2021 The Author(s). Transplantation Direct. Published by Wolters Kluwer Health, Inc.)

Introduction: A primary acinar cell carcinoma (ACC) of the liver was incidentally diagnosed in a clinically asymptomatic 80-year-old man. This study aimed to delineate critical diagnostic characteristics of an ACC originating uniquely from the liver to improve its future identification., Presentation of Case: Enhanced MRI revealed a heterogenous, cystic 7.7 × 11.1 × 10.4 cm tumour occupying hepatic segments II and III. The mass demonstrated mild diffuse enhancement in hepatic arterial phase with minimal portal venous washout in a liver without cirrhotic features. A central stellate T2-hyperintense necrotic scar and outer capsule were apparent. No primary lesion or metastasis outside the liver was discernable. Post-left hepatic lobectomy, the tumour immunophenotype was atypical for presumptive diagnoses of hepatocellular carcinoma (HCC) or cholangiocarcinoma. Extensive morphologic workup on electron microscopy definitively diagnosed primary hepatic ACC by establishing presence of secretory zymogen-like granules, intracytoplasmic microvilli and acinar cell differentiation. Cytopathology revealed cellular lumen expressing PAS-positive diastase-resistant granular cytoplasmic contents., Discussion: This case showcased the novel utility of electron microscopy that was crucial in yielding the definitive diagnosis. The previous literature on hepatic ACC was compiled here in context of the present case. The mechanism of hepatic acinar cell localization was also discussed., Conclusion: Primary hepatic ACC may easily be confused for other lesions due to nonspecific imaging patterns. Specifically, the presence of a central scar without risk factors for HCC can favour a diagnosis of benign entities such as focal nodular hyperplasia (FNH). Electron microscopy presents an important tool to identify primary hepatic ACC and may improve future patient outcomes., (Copyright © 2019 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Deciding who should receive a liver transplant (LT) depends on both urgency and utility. Most survival scores are validated through discriminative tests, which compare predicted outcomes between patients. Assessing post-transplant survival utility is not discriminate, but should be "calibrated" to be effective. There are currently no such calibrated models. We developed and validated a novel calibrated model to predict individual survival after LT for Primary Sclerosing Cholangitis (PSC). We applied a software tool, PSSP, to adult patients in the Scientific Registry of Transplant Recipients (n = 2769) who received a LT for PSC between 2002 and 2013; this produced a model for predicting individual survival distributions for novel patients. We also developed an appropriate evaluation measure, D-calibration, to validate this model. The learned PSSP model showed an excellent D-calibration (p = 1.0), and passed the single-time calibration test (Hosmer-Lemeshow p-value of over 0.05) at 0.25, 1, 5 and 10 years. In contrast, the model based on traditional Cox regression showed worse calibration on long-term survival and failed at 10 years (Hosmer-Lemeshow p value = 0.027). The calculator and visualizer are available at: http://pssp.srv.ualberta.ca/calculator/liver&#95;transplant&#95;2002. In conclusion we present a new tool that accurately estimates individual post liver transplantation survival.

O-glycosylation of the Plasmodium sporozoite surface proteins CSP and TRAP was recently identified, but the role of this modification in the parasite life cycle and its relevance to vaccine design remain unclear. Here, we identify the Plasmodium protein O-fucosyltransferase (POFUT2) responsible for O-glycosylating CSP and TRAP. Genetic disruption of POFUT2 in Plasmodium falciparum results in ookinetes that are attenuated for colonizing the mosquito midgut, an essential step in malaria transmission. Some POFUT2-deficient parasites mature into salivary gland sporozoites although they are impaired for gliding motility, cell traversal, hepatocyte invasion, and production of exoerythrocytic forms in humanized chimeric liver mice. These defects can be attributed to destabilization and incorrect trafficking of proteins bearing thrombospondin repeats (TSRs). Therefore, POFUT2 plays a similar role in malaria parasites to that in metazoans: it ensures the trafficking of Plasmodium TSR proteins as part of a non-canonical glycosylation-dependent endoplasmic reticulum protein quality control mechanism.The role of O-glycosylation in the malaria life cycle is largely unknown. Here, the authors identify a Plasmodium protein O-fucosyltransferase and show that it is important for normal trafficking of a subset of surface proteins, particularly CSP and TRAP, and efficient infection of mosquito and vertebrate hosts.

The malaria sporozoite injected by a mosquito migrates to the liver by traversing host cells. The sporozoite also traverses hepatocytes before invading a terminal hepatocyte and developing into exoerythrocytic forms. Hepatocyte infection is critical for parasite development into merozoites that infect erythrocytes, and the sporozoite is thus an important target for antimalarial intervention. Here, we investigated two abundant sporozoite proteins of the most virulent malaria parasite Plasmodium falciparum and show that they play important roles during cell traversal and invasion of human hepatocytes. Incubation of P. falciparum sporozoites with R1 peptide, an inhibitor of apical merozoite antigen 1 (AMA1) that blocks merozoite invasion of erythrocytes, strongly reduced cell traversal activity. Consistent with its inhibitory effect on merozoites, R1 peptide also reduced sporozoite entry into human hepatocytes. The strong but incomplete inhibition prompted us to study the AMA-like protein, merozoite apical erythrocyte-binding ligand (MAEBL). MAEBL-deficient P. falciparum sporozoites were severely attenuated for cell traversal activity and hepatocyte entry in vitro and for liver infection in humanized chimeric liver mice. This study shows that AMA1 and MAEBL are important for P. falciparum sporozoites to perform typical functions necessary for infection of human hepatocytes. These two proteins therefore have important roles during infection at distinct points in the life cycle, including the blood, mosquito, and liver stages., (© 2017 John Wiley & Sons Ltd.)

Malaria sporozoites are deposited into the skin by mosquitoes and infect hepatocytes. The molecular basis of how Plasmodium falciparum sporozoites migrate through host cells is poorly understood, and direct evidence of its importance in vivo is lacking. Here, we generated traversal-deficient sporozoites by genetic disruption of sporozoite microneme protein essential for cell traversal (PfSPECT) or perforin-like protein 1 (PfPLP1). Loss of either gene did not affect P. falciparum growth in erythrocytes, in contrast with a previous report that PfPLP1 is essential for merozoite egress. However, although traversal-deficient sporozoites could invade hepatocytes in vitro, they could not establish normal liver infection in humanized mice. This is in contrast with NF54 sporozoites, which infected the humanized mice and developed into exoerythrocytic forms. This study demonstrates that SPECT and perforin-like protein 1 (PLP1) are critical for transcellular migration by P. falciparum sporozoites and demonstrates the importance of cell traversal for liver infection by this human pathogen., (Copyright © 2017 The Author(s). Published by Elsevier Inc. All rights reserved.)

Introduction: To identify the impact of portal vein thrombosis (PVT) and associated medical and surgical factors on outcomes post liver transplant (LT)., Material and Methods: Two analyses were performed. Analysis One: cohort study of 505 consecutive patients who underwent LT (Alberta) between 01/2002-12/2012. PVT was identified in 61 (14%) patients. Analysis Two: cohort study of 144 consecutive PVT patients from two sites (Alberta and London) during the same period. Cox multivariable survival analysis was used to identify independent associations with post-LT mortality., Results: In Analysis One (Alberta), PVT was not associated with post-LT mortality (log rank p = 0.99). On adjusted analysis, complete/occlusive PVT was associated with increased mortality (Hazard Ratio (HR) 8.4, p &lt; 0.001). In Analysis Two (Alberta and London), complete/occlusive PVT was associated with increased mortality only on unadjusted analysis (HR 3.7, p = 0.02). On adjusted analysis, Hepatitis C (HR 2.1, p = 0.03) and post-LT portal vein re-occlusion (HR 3.2, p = 0.01) were independently associated with increased mortality., Conclusion: Well-selected LT patients who had PVT prior to LT had similar post-LT outcomes to non-PVT LT recipients. Subgroups of PVT patients who did worse post-LT (complete/occlusive thrombosis pre-LT, Hepatitis C or post-LT portal vein re-occlusion) warrant closer evaluation in listing and management post-LT.

Background: We have previously described the existence of two phenotypically distinct cell subsets in ALK-positive anaplastic large cell lymphoma (ALK + ALCL) based on their differential responsiveness to a Sox2 reporter (SRR2), with reporter-responsive (RR) cells being more tumorigenic and chemoresistant than reporter-unresponsive (RU) cells. However, the regulator(s) of RU/RR dichotomy are not identified. In this study, we aim to delineate the key regulator(s) of RU/RR dichotomy., Methods: JASPER motif match analysis was used to identify the putative factors binding to SRR2 sequence. SRR2 probe pull-down assay and quantitate real-time PCR were performed to analyze the regulation of Sox2 transcriptional activity by MYC. Methylcellulose colony formation assay, chemoresistance to doxorubicin and mouse xenograft study were performed to investigate the biological functions of MYC. PCR array and western blotting were executed to study related signaling pathways that regulate MYC expression. Immunofluorescence and immunohistochemistry assay were initiated to evaluate the expression of MYC and its correlation with its regulator by chi-square test analysis in human primary tumor cells., Results: We identified MYC as a potential regulator of RU/RR dichotomy. In support of its role, MYC was highly expressed in RR cells compared to RU cells, and inhibition of MYC substantially decreased the Sox2/SRR2 binding, Sox2 transcriptional activity, chemoresistance, and methylcellulose colony formation. In contrast, enforced expression of MYC in RU cells conferred the RR phenotype. The Wnt/β-catenin pathway, a positive regulator of MYC, was highly active in RR but not RU cells. While inhibition of this pathway in RR cells substantially decreased MYC expression and SRR2 reporter activity, experimental activation of this pathway led to the opposite effects in RU cells. Collectively, our results support a model in which a positive feedback loop involving Wnt/β-catenin/MYC and Sox2 contributes to the RR phenotype. In a mouse xenograft model, RU cells stably transfected with MYC showed upregulation of the Wnt/β-catenin/MYC/Sox2 axis and increased tumorigenecity. Correlating with these findings, there was a significant correlation between the expression of active β-catenin and MYC in ALK + ALCL primary tumor cells., Conclusions: A positive feedback loop involving the Wnt/β-catenin/MYC/Sox2 axis defines a highly tumorigenic cell subset in ALK + ALCL.

Unlabelled: Individuals chronically infected with hepatitis C virus (HCV) commonly exhibit hepatic intracellular lipid accumulation, termed steatosis. HCV infection perturbs host lipid metabolism through both cellular and virus-induced mechanisms, with the viral core protein playing an important role in steatosis development. We have recently identified a liver protein, the cell death-inducing DFFA-like effector B (CIDEB), as an HCV entry host dependence factor that is downregulated by HCV infection in a cell culture model. In this study, we investigated the biological significance and molecular mechanism of this downregulation. HCV infection in a mouse model downregulated CIDEB in the liver tissue, and knockout of the CIDEB gene in a hepatoma cell line results in multiple aspects of lipid dysregulation that can contribute to hepatic steatosis, including reduced triglyceride secretion, lower lipidation of very-low-density lipoproteins, and increased lipid droplet (LD) stability. The potential link between CIDEB downregulation and steatosis is further supported by the requirement of the HCV core and its LD localization for CIDEB downregulation, which utilize a proteolytic cleavage event that is independent of the cellular proteasomal degradation of CIDEB., Importance: Our data demonstrate that HCV infection of human hepatocytesin vitroandin vivoresults in CIDEB downregulation via a proteolytic cleavage event. Reduction of CIDEB protein levels by HCV or gene editing, in turn, leads to multiple aspects of lipid dysregulation, including LD stabilization. Consequently, CIDEB downregulation may contribute to HCV-induced hepatic steatosis., (Copyright © 2016, American Society for Microbiology. All Rights Reserved.)

Cytopathic effects are currently believed to contribute to hepatitis C virus (HCV)-induced liver injury and are readily observed in Huh7.5 cells infected with the JFH-1 HCV strain, manifesting as apoptosis highly correlated with growth arrest. Reactive oxygen species, which are induced by HCV infection, have recently emerged as activators of AMP-activated protein kinase. The net effect is ATP conservation via on/off switching of metabolic pathways that produce/consume ATP. Depending on the scenario, this can have either pro-survival or pro-apoptotic effects. We demonstrate reactive oxygen species-mediated activation of AMP-activated kinase in Huh7.5 cells during HCV (JFH-1)-induced growth arrest. Metabolic labeling experiments provided direct evidence that lipid synthesis is attenuated, and β-oxidation is enhanced in these cells. A striking increase in nuclear peroxisome proliferator-activated receptor α, which plays a dominant role in the expression of β-oxidation genes after ligand-induced activation, was also observed, and we provide evidence that peroxisome proliferator-activated receptor α is constitutively activated in these cells. The combination of attenuated lipid synthesis and enhanced β-oxidation is not conducive to lipid accumulation, yet cellular lipids still accumulated during this stage of infection. Notably, the serum in the culture media was the only available source for polyunsaturated fatty acids, which were elevated (2-fold) in the infected cells, implicating altered lipid import/export pathways in these cells. This study also provided the first in vivo evidence for enhanced β-oxidation during HCV infection because HCV-infected SCID/Alb-uPA mice accumulated higher plasma ketones while fasting than did control mice. Overall, this study highlights the reprogramming of hepatocellular lipid metabolism and bioenergetics during HCV infection, which are predicted to impact both the HCV life cycle and pathogenesis., (© 2016 by The American Society for Biochemistry and Molecular Biology, Inc.)

Background. Since 2002, the Model of End-Stage Liver Disease (MELD) has been used for allocation of liver transplants (LT) in the USA. In Canada, livers were allocated by the CanWAIT algorithm. The aim of this study was to compare the abilities of MELD, Child-Pugh (CP), and CanWAIT status to predict 3-month and 1-year mortality before LT in Canadian patients and to describe the use of MELD in Canada. Methods. Validation of MELD was performed in 320 patients listed for LT in Alberta (1998-2002). In October 2014, a survey of MELD use by Canadian LT centers was conducted. Results. Within 1 year of listing, 47 patients were removed from the waiting list (29 deaths, 18 too ill for LT). Using logistic regression, the MELD and CP were better than the CanWAIT at predicting 3-month (AUROC: 0.79, 0.78, and 0.59; p = 0.0002) and 1-year waitlist mortality (AUROC: 0.70, 0.70, and 0.55; p = 0.0023). Beginning in 2004, MELD began to be adopted by Canadian LT programs but its use was not standardized. Conclusions. Compared with the CanWAIT system, the MELD score was significantly better at predicting LT waitlist mortality. MELD-sodium (MELD-Na) has now been adopted for LT allocation in Canada.

The tumorigenicity of most cases of ALK-positive anaplastic large-cell lymphoma (ALK+ ALCL) is driven by the oncogenic fusion protein NPM-ALK in a STAT3-dependent manner. Because it has been shown that STAT3 can be inhibited by STAT1 in some experimental models, we hypothesized that the STAT1 signaling pathway is defective in ALK+ ALCL, thereby leaving the STAT3 signaling unchecked. Compared with normal T cells, ALK+ ALCL tumors consistently expressed a low level of STAT1. Inhibition of the ubiquitin-proteasome pathway appreciably increased STAT1 expression in ALK+ ALCL cells. Furthermore, we found evidence that NPM-ALK binds to and phosphorylates STAT1, thereby promoting its proteasomal degradation in a STAT3-dependent manner. If restored, STAT1 is functionally intact in ALK+ ALCL cells, because it effectively upregulated interferon-γ, induced apoptosis/cell-cycle arrest, potentiated the inhibitory effects of doxorubicin, and suppressed tumor growth in vivo. STAT1 interfered with the STAT3 signaling by decreasing STAT3 transcriptional activity/DNA binding and its homodimerization. The importance of the STAT1/STAT3 functional interaction was further highlighted by the observation that short interfering RNA knockdown of STAT1 significantly decreased apoptosis induced by STAT3 inhibition. Thus, STAT1 is a tumor suppressor in ALK+ ALCL. Phosphorylation and downregulation of STAT1 by NPM-ALK represent other mechanisms by which this oncogenic tyrosine kinase promotes tumorigenesis., (© 2015 by The American Society of Hematology.)

Background: Improving estimation of long-term survival of patients with end-stage liver disease after orthotopic liver transplantation (OLT) would optimize decisions on eligibility for transplant. We aimed to externally validate previously derived Charlson Comorbity Index for OLT (CCI-OLT); subsequently, we developed a new model to predict 5-year mortality after transplant., Material and Methods: This single center retrospective cohort study included 524 consecutive adult cirrhotic patients who underwent OLT in 2002-2012. External validation of CCI-OLT used Kaplan-Meier method. Derivation of the new predictive model used Cox proportional hazards regression., Results: One-, 3-, and 5-year cumulative survival after OLT was 89%, 80%, and 73%, respectively. CCI-OLT was not associated with 5-year mortality after transplant (P = 0.34). We derived and internally validated a new predictive model of 5-year mortality after OLT based on six pre-transplant characteristics of patients: age, body mass index, hepatitis C, hepatic encephalopathy, intensive care unit stay at transplant, and live donor (C-index = 0.64). We further developed a nomogram to estimate individual probability of 1-, 3-, and 5-year survival after OLT., Conclusions: In our cohort, CCI-OLT was not associated with survival following transplant. The new predictive model discriminative capacity was only modest, suggesting that pre-transplant characteristics are of limited value in predicting post-transplant outcomes in thoroughly selected patients.

Aims/hypothesis: There are potential advantages to the low-temperature (-196 °C) banking of isolated islets, including the maintenance of viable islets for future research. We therefore assessed the in vitro and in vivo function of islets cryopreserved for nearly 20 years., Methods: Human islets were cryopreserved from 1991 to 2001 and thawed between 2012 and 2014. These were characterised by immunostaining, patch-clamp electrophysiology, insulin secretion, transcriptome analysis and transplantation into a streptozotocin (STZ)-induced mouse model of diabetes., Results: The cryopreservation time was 17.6 ± 0.4 years (n = 43). The thawed islets stained positive with dithizone, contained insulin-positive and glucagon-positive cells, and displayed levels of apoptosis and transcriptome profiles similar to those of freshly isolated islets, although their insulin content was lower. The cryopreserved beta cells possessed ion channels and exocytotic responses identical to those of freshly isolated beta cells. Cells from a subset of five donors demonstrated similar perifusion insulin secretion profiles pre- and post-cryopreservation. The transplantation of cryopreserved islets into the diabetic mice improved their glucose tolerance but did not completely normalise their blood glucose levels. Circulating human insulin and insulin-positive grafts were detectable at 10 weeks post-transplantation., Conclusions/interpretation: We have demonstrated the potential for long-term banking of human islets for research, which could enable the use of tissue from a large number of donors with future technologies to gain new insight into diabetes.

Background: Cirrhotic patients with Model for End-stage Liver Disease (MELD) score ≥ 40 have high risk for death without liver transplant (LT)., Objective: To evaluate these patients' outcomes after LT., Methods: The present study analyzed a retrospective cohort of 519 cirrhotic adult patients who underwent LT at a single Canadian centre between 2002 and 2012. Primary exposure was severity of liver disease measured by MELD score at LT (≥ 40 versus < 40). Primary outcome was duration of first intensive care unit (ICU) stay after LT. Secondary outcomes were duration of first hospital stay after LT, rate of ICU readmission, re-LT and survival rates., Results: On the day of LT, 5% (28 of 519) of patients had a MELD score ≥ 40. These patients had longer first ICU stays after LT (14 versus two days; P < 0.001). MELD score ≥ 40 at LT was independently associated with first ICU stay after LT ≥ 10 days (OR 3.21). These patients had longer first hospital stays after LT (45 versus 18 days; P < 0.001); however, there was no significant difference in the rate of ICU readmission (18% versus 22%; P = 0.58) or re-LT rate (4% versus 4%; P = 1.00). Cumulative survival at one month, three months, one year, three years and five years was 98%, 96%, 90%, 79% and 72%, respectively. There was no significant difference in cumulative survival stratified according to MELD score ≥ 40 versus < 40 at LT (P = 0.59)., Conclusions: Cirrhotic patients with MELD score ≥ 40 at LT utilize greater postoperative health resources; however, they derive similar long-term survival benefit from LT.

We have recently described a novel phenotypic dichotomy within estrogen receptor-positive breast cancer cells; the cell subset responsive to a Sox2 regulatory region (SRR2) reporter (RR cells) are significantly more tumorigenic than the reporter unresponsive (RU) cells. Here, we report that a similar phenomenon also exists in triple negative breast cancer (TNBC), with RR cells more tumorigenic than RU cells. First, examination of all 3 TNBC cell lines stably infected with the SRR2 reporter revealed the presence of a cell subset exhibiting reporter activity. Second, RU and RR cells purified by flow cytometry showed that RR cells expressed higher levels of CD44, generated more spheres in a limiting dilution mammosphere formation assay, and formed larger and more complex structures in Matrigel. Third, within the CD44(High)/CD24- tumor-initiating cell population derived from MDA-MB-231, RR cells were significantly more tumorigenic than RU cells in an in vivo SCID/Beige xenograft mouse model. Examination of 4 TNBC tumors from patients also revealed the presence of a RR cell subset, ranging from 1.1-3.8%. To conclude, we described a novel phenotypic heterogeneity within TNBC, and the SRR2 reporter responsiveness is a useful marker for identifying a highly tumorigenic cell subset within the CD44(High)/CD24-tumor-initiating cell population.

For selected patients with type 1 diabetes, β-cell replacement is the treatment of choice, either by islet transplantation (ITX) or whole pancreas transplantation (PTX). When either modality fails, current practice is to consider retransplantation, or return to exogenous insulin. We investigate outcomes with PTX after failed ITX (PAI), and ITX after failed PTX (IAP). All patients receiving PAI or IAP at a single institution were identified. Donor and recipient variables were documented, including transplant outcomes analyzed for insulin requirement and metabolic control. Five subjects were listed for PAI, and 2 received transplants. Of the 4 listed for IAP, 3 have received transplants. The mean waitlist time was 4.5 ± 4.1 y for PAI and 0.35 ±0 .4 y for IAP (p = 0.08). Metabolic control was excellent after PAI, with 2/2 insulin-independent. After IAP, 1/2 achieved insulin independence and good metabolic control after 2 islet infusions. The third could not receive 2(nd) infusion and presented c-peptide levels < 0.1 nmol/L. Both strategies are feasible. The outcomes after PAI in our center must be offset by much longer waitlist time due to the sensitization status of these patients. Data from multicentre experience will allow more robust comparative outcomes to be made, the current observations being restricted to a limited patient set.

Introduction: Critically ill cirrhosis patients awaiting liver transplantation (LT) often receive prioritization for organ allocation. Identification of patients most likely to benefit is essential. The purpose of this study was to examine whether the Sequential Organ Failure Assessment (SOFA) score can predict 90-day mortality in critically ill recipients of LT and whether it can predict receipt of LT among critically ill cirrhosis listed awaiting LT., Methods: We performed a multicenter retrospective cohort study consisting of two datasets: (a) all critically-ill cirrhosis patients requiring intensive care unit (ICU) admission before LT at five transplant centers in Canada from 2000 through 2009 (one site, 1990 through 2009), and (b) critically ill cirrhosis patients receiving LT from ICU (n = 115) and those listed but not receiving LT before death (n = 106) from two centers where complete data were available., Results: In the first dataset, 198 critically ill cirrhosis patients receiving LT (mean (SD) age 53 (10) years, 66% male, median (IQR) model for end-stage liver disease (MELD) 34 (26-39)) were included. Mean (SD) SOFA scores at ICU admission, at 48 hours, and at LT were 12.5 (4), 13.0 (5), and 14.0 (4). Survival at 90 days was 84% (n = 166). In multivariable analysis, only older age was independently associated with reduced 90-day survival (odds ratio (OR), 1.07; 95% CI, 1.01 to 1.14; P = 0.013). SOFA score did not predict 90-day mortality at any time. In the second dataset, 47.9% (n = 106) of cirrhosis patients listed for LT died in the ICU waiting for LT. In multivariable analysis, higher SOFA at 48 hours after admission was independently associated with lower probability of receiving LT (OR, 0.89; 95% CI, 0.82 to 0.97; P = 0.006). When including serum lactate and SOFA at 48 hours in the final model, elevated lactate (at 48 hours) was also significantly associated with lower likelihood of receiving LT (0.32; 0.17 to 0.61; P = 0.001)., Conclusions: SOFA appears poor at predicting 90-day survival in critically ill cirrhosis patients after LT, but higher SOFA score and elevated lactate 48 hours after ICU admission are associated with a lower probability receiving LT. Older critically ill cirrhosis patients (older than 60) receiving LT have worse 90-day survival and should be considered for LT with caution.

Cyclosporine A (CSA) has potent effects against hepatitis C virus (HCV) in vitro, but its clinical efficacy after liver transplantation (LT) is uncertain. We evaluated the impact of CSA and tacrolimus (TAC) with or without concomitant interferon (IFN) therapy on serum HCV titers in a chimeric mouse model of HCV infection. Six groups of HCV-infected mice received only the vehicle, IFN, CSA, CSA and IFN, TAC, or TAC and IFN for 4 weeks. The quantitative HCV polymerase chain reaction levels were determined after 1, 2, and 4 weeks of drug administration. There were no significant differences in the HCV titers after 4 weeks of treatment between the non-IFN-treated groups (log HCV titers: 3.5 ± 0.3 for the vehicle group, 4.4 ± 0.6 for the CSA group, and 4.3 ± 0.4 for the TAC group, P = 0.3). Although IFN had a consistent effect of reducing HCV titers across the groups, there was no significant impact of CSA on HCV levels when it was used alone or in combination with IFN at any time point. The 4-week HCV titers were as follows: 3.2 ± 0.3 for the IFN group, 4.7 ± 0.4 for the CSA/IFN group, and 4.0 ± 0.5 for the TAC/IFN group (P = 0.07). The CSA/IFN and TAC/IFN groups did not differ significantly (P = 0.6). Six of the 7 animals in the IFN group (85.7%) had an HCV titer decline ≥ 1 log, whereas in the test groups (CSA/IFN and TAC/IFN), 6 of 9 animals (66.7%) achieved a 1-log decline in the HCV titer (P = 1). Using this animal model, we could find no evidence supporting the routine use of CSA after LT in HCV-infected patients., (Copyright © 2011 American Association for the Study of Liver Diseases.)

Primary human hepatocytes isolated from patient biopsies represent the most physiologically relevant cell culture model for hepatitis C virus (HCV) infection, but these primary cells are not readily accessible, display individual variability, and are largely refractory to genetic manipulation. Hepatocyte-like cells differentiated from pluripotent stem cells provide an attractive alternative as they not only overcome these shortcomings but can also provide an unlimited source of noncancer cells for both research and cell therapy. Despite its promise, the permissiveness to HCV infection of differentiated human hepatocyte-like cells (DHHs) has not been explored. Here we report a novel infection model based on DHHs derived from human embryonic (hESCs) and induced pluripotent stem cells (iPSCs). DHHs generated in chemically defined media under feeder-free conditions were subjected to infection by both HCV derived in cell culture (HCVcc) and patient-derived virus (HCVser). Pluripotent stem cells and definitive endoderm were not permissive for HCV infection whereas hepatic progenitor cells were persistently infected and secreted infectious particles into culture medium. Permissiveness to infection was correlated with induction of the liver-specific microRNA-122 and modulation of cellular factors that affect HCV replication. RNA interference directed toward essential cellular cofactors in stem cells resulted in HCV-resistant hepatocyte-like cells after differentiation. The ability to infect cultured cells directly with HCV patient serum, to study defined stages of viral permissiveness, and to produce genetically modified cells with desired phenotypes all have broad significance for host-pathogen interactions and cell therapy.

Percutaneous transhepatic portal access avoids surgery but is rarely associated with bleeding or portal venous thrombosis (PVT). We herein report our large, single-center experience of percutaneous islet implantation and evaluate risk factors of PVT and graft function. Prospective data were collected on 268 intraportal islet transplants (122 subjects). A portal venous Doppler ultrasound was obtained on Days 1 and 7 posttransplant. Therapeutic heparinization, complete ablation of the portal catheter tract with Avitene paste and limiting packed cell volume (PCV) to <5 mL completely prevented any portal thrombosis in the most recent 101 islet transplant procedures over the past 5 years. In the previous cumulative experience, partial thrombosis did not affect islet function. Standard liver volume correlated negatively (r =-0.257, p < 0.001) and PCV correlated positively with portal pressure rise (r = 0.463, p < 0.001). Overall, partial portal thrombosis occurred after 10 procedures (overall incidence 3.7%, most recent 101 patient incidence 0%). There were no cases of complete thrombosis and no patient developed sequelae of portal hypertension. In conclusion, portal thrombosis is a preventable complication in clinical islet transplantation, provided therapeutic anticoagulation is maintained and PCV is limited to <5 mL., (©Copyright 2011 The American Society of Transplantation and the American Society of Transplant Surgeons.)

Background: While some immunosuppression strategies may accelerate hepatitis C virus (HCV) recurrence after liver transplantation (LT), the impact of sirolimus (SRL) is not known., Objective: To assess the risk of biopsy-proven HCV recurrence and patient survival using known and suspected risk factors for HCV recurrence as covariates., Methods: A retrospective analysis of 141 consecutive patients, including 88 who received de novo SRL therapy, who had undergone a first LT for HCV cirrhosis was conducted. Known and suspected risk factor covariates including transplant era, donor and recipient age, Model for End-stage Liver Disease score, cold ischemia time, immunosuppressive drugs and steroid treatment rejection rates were used in the assessment., Results: Overall, 72.3% of the cohort developed biopsy-proven HCV recurrence. The incidence of HCV recurrence was not significantly different for patients treated with SRL (75% versus 69.8%; P=0.5). There was no difference found for time to recurrence, nor did mean activity or fibrosis scores differ at the time of initial recurrence. However, on follow-up using serial biopsies in patients with recurrence, the mean activity and fibrosis scores were significantly lower in the SRL group. Donor age and acute rejection episodes were the only factors affecting the HCV recurrence rate (expB 1.02 [95% CI 1.01 to 1.03]); P=0.03; and expB 2.8 [95% CI 1.8 to 4.3]; P<0.01], respectively). SRL treatment did not alter patient survival rates. Among patients treated with SRL-based immunosuppression, higher drug area under the curve levels were associated with a trend to lower disease activity and fibrosis at diagnosis; however, higher SRL levels were associated with shorter recurrence-free survival (P=0.038)., Conclusion: Results of the present analysis suggest that de novo SRL-based immunosuppression can be safely used in patients undergoing LT for HCV-associated liver disease; however, SRL-based immunosuppression did not significantly affect the timing or severity of post-transplant HCV recurrence. HCV recurrence in SRL-treated patients had lower progressive activity and fibrosis levels on serial biopsy.

Hepatocytes are vulnerable to loss of function and viability in culture. Modified culture methods have been applied to maintain their functional status. Heterotypic interactions between hepatocytes and nonparenchymal neighbors in liver milieu are thought to modulate cell differentiation. Cocultivation of hepatocyte with various cell types has been applied to mimic the hepatic environment. Bone marrow stromal cells (BMSC) are plastic cell lines capable of transforming to other cell types. In this study hepatocyte coculture with BMSCs achieved long-term function of human hepatocytes in culture for 4 weeks. In vitro functional status of human hepatocytes in BMSC coculture was compared with fibroblast coculture and collagen culture by measuring albumin, human-α-1-antitrypsin (hAAT), urea secretion, CYP450 activity, and staining for intracellular albumin and glycogen. After 2 weeks in culture hepatocytes were retrieved and transplanted to severe combined immunodeficiency/albumin linked-urokinase type plasminogen activator (SCID Alb-uPA) mice and engraft-ment capacity was analyzed by human hepatic-specific function measured by hAAT levels in mouse serum, and Alu staining of mouse liver for human hepatocytes. Hepatocytes from BMSC coculture had significantly higher albumin, hAAT secretion, urea production, and cytochrome P450 (CYP450) activity than other culture groups. Staining confirmed the higher functional status in BMSC coculture. Transplantation of hepatocytes detached from BMSC cocultures showed significantly higher engraftment function than hepatocytes from other culture groups measured by hAAT levels in mouse serum. In conclusion, BMSC coculture has excellent potential for hepatocyte function preservation in vitro and in vivo after transplant. It is possible to use BMSC hepatocyte coculture as a supply of cell therapy in liver disease.

Hepatocellular carcinoma (HCC) is one of only a few malignancies with an increasing incidence in North America. Because the vast majority of HCCs occur in the setting of a cirrhotic liver, management of this malignancy is best performed in a multidisciplinary group that recognizes the importance of liver function, as well as patient and tumour characteristics. The Barcelona Clinic Liver Cancer (BCLC) staging system is preferred for HCC because it incorporates the tumour characteristics (ie, tumour-node-metastasis stage), the patient's performance status and liver function according to the Child-Turcotte-Pugh classification, and then links the BCLC stage to recommended therapeutic interventions. However, the BCLC algorithm does not recognize the potential role of radiofrequency ablation for very early stage HCC, the expanding role of liver transplantation in the management of HCC, the role of transarterial chemoembolization in single large tumours, the potential role of transarterial radioembolization with 90Yttrium and the limited evidence for using sorafenib in Child- Turcotte-Pugh class B cirrhotic patients. The current review article presents an evidence-based approach to the multidisciplinary management of HCC along with a new algorithm for the management of HCC that incorporates the BCLC staging system and the authors' local selection criteria for resection, ablative techniques, liver transplantation, transarterial chemoembolization, transarterial radioembolization and sorafenib in Alberta.

Although multiple determinants for hepatitis C virus (HCV) infection are known, it remains partly unclear what determines the human specificity of HCV infection. Presumably, the presence of appropriate entry receptors is essential, and this may explain why HCV is unable to infect nonhuman hepatocytes. However, using mice with chimeric human livers, we show in this study that the presence of human hepatocytes, and therefore human entry receptors, is not sufficient for HCV infection. In successfully transplanted SCID/Alb-uPA mice, infection with HCV is reliable only when ∼70-80% of the liver consists of human hepatocytes. We show that chimeric mice, which are hard to infect with HCV, have significant groups of human hepatocytes that are readily infected with hepatitis B virus. Thus it is unlikely that the lack of infection with HCV can simply be attributed to low hepatocyte numbers. We investigated whether the humanization of lipoprotein profiles is positively associated with infection success. We show that the lipoprotein profiles of chimeric mice become more human-like at high levels of engraftment of human hepatocytes. This and expression of markers of human lipoprotein biosynthesis, human apolipoprotein B (ApoB) and cholesterol ester transfer protein (CETP), show a strong positive correlation with successful infection. Association of HCV in the blood of chimeric mice to ApoB-containing lipoproteins is comparable to association of HCV in patient serum and provides further support for a critical role for ApoB-containing lipoproteins in the infectious cycle of HCV. Our data suggest that the weakest link in the HCV infection chain does not appear to be the presence of human hepatocytes per se. We believe that HCV infection also depends on the presence of sufficient levels of human lipoproteins.

The severe combined immunodeficiency/albumin linked-urokinase type plasminogen activator (SCID/Alb-uPA) human liver chimeric mouse model has added a new dimension to studies of liver based human diseases and has important potential for study of human hepatic drug metabolism. However, it remains unclear if natural killer (NK) cell in SCID/Alb-uPA mice has an important negative impact on engraftment and expansion of human hepatocytes after transplantation. Here, we explore the role of mouse NK cells in the rejection of transplanted human hepatocytes in SCID/Alb-uPA mice. We assessed NK cell activity in vivo, using (125)I-iodo-2'-deoxyuridine incorporation assay. Low serum human alpha-1 antitrypsin (hAAT, <10 microg/ml) recipients, representing graft failure, showed resistance to engraftment of MHC class I knockout marrow (indicating high NK cell activity), while NK cell-depleted low hAAT recipients and high hAAT (>100 microg/ml) recipients accepted MHC class I knockout marrow, indicating a correlation between low NK cell activity, in vivo, and high level human hepatocyte engraftment. We also showed that higher level engraftment of human hepatocytes was achieved in both NK cell-depleted SCID/Alb-uPA mice and Rag2(-/-)gammac(-/-)/Alb-uPA (T,B and NK cell deficient) mice compared with untreated SCID/Alb-uPA mice. These results support a critical role for mouse NK cells in the rejection of human hepatocytes xenotransplanted to immunodeficient mice.

Human hepatocyte transplantation is an alternative treatment for acute liver failure and liver diseases involving enzyme deficiencies. Although it has been successfully applied in selected recipients, both isolation and transplantation outcomes have the potential to be improved by better donor selection. This study assessed the impact of various donor variables on isolation outcomes (yield and viability) and posttransplant engraftment, using the SCID/Alb-uPA (severe combined immunodeficient/urokinase type plasminogen activator under the control of an albumin promoter) human liver chimeric mouse model. Human hepatocytes were obtained from 90 human liver donor specimens and were transplanted into 3942 mice. Multivariate analysis revealed improved viability with younger donors (P = 0.038) as well as with shorter warm ischemic time (P = 0.012). Hepatocyte engraftment, assessed by the posttransplant level of serum human alpha1-antitrypsin, was improved with shorter warm ischemia time. Hepatocytes isolated from older donors (>or=60 years) had lower viability and posttransplant engraftment (P

Background: The potential anti-cancer effects of mammalian target of rapamycin (mTOR) inhibitors are being intensively studied. To date, however, few randomised clinical trials (RCT) have been performed to demonstrate anti-neoplastic effects in the pure oncology setting, and at present, no oncology endpoint-directed RCT has been reported in the high-malignancy risk population of immunosuppressed transplant recipients. Interestingly, since mTOR inhibitors have both immunosuppressive and anti-cancer effects, they have the potential to simultaneously protect against immunologic graft loss and tumour development. Therefore, we designed a prospective RCT to determine if the mTOR inhibitor sirolimus can improve hepatocellular carcinoma (HCC)-free patient survival in liver transplant (LT) recipients with a pre-transplant diagnosis of HCC., Methods/design: The study is an open-labelled, randomised, RCT comparing sirolimus-containing versus mTOR-inhibitor-free immunosuppression in patients undergoing LT for HCC. Patients with a histologically confirmed HCC diagnosis are randomised into 2 groups within 4-6 weeks after LT; one arm is maintained on a centre-specific mTOR-inhibitor-free immunosuppressive protocol and the second arm is maintained on a centre-specific mTOR-inhibitor-free immunosuppressive protocol for the first 4-6 weeks, at which time sirolimus is initiated. A 21/2 -year recruitment phase is planned with a 5-year follow-up, testing HCC-free survival as the primary endpoint. Our hypothesis is that sirolimus use in the second arm of the study will improve HCC-free survival. The study is a non-commercial investigator-initiated trial (IIT) sponsored by the University Hospital Regensburg and is endorsed by the European Liver and Intestine Transplant Association; 13 countries within Europe, Canada and Australia are participating., Discussion: If our hypothesis is correct that mTOR inhibition can reduce HCC tumour growth while simultaneously providing immunosuppression to protect the liver allograft from rejection, patients should experience less post-transplant problems with HCC recurrence, and therefore could expect a longer and better quality of life. A positive outcome will likely change the standard of posttransplant immunosuppressive care for LT patients with HCC., Trial Register: Trial registered at http://www.clinicaltrials.gov: NCT00355862(EudraCT Number: 2005-005362-36).

Background: Severe Combined Immune Deficient (SCID)/Urokinase-type Plasminogen Activator (uPA) mice undergo liver failure and are useful hosts for the propagation of transplanted human hepatocytes (HH) which must compete with recipient-derived hepatocytes for replacement of the diseased liver parenchyma. While partial replacement by HH has proven useful for studies with Hepatitis C virus, complete replacement of SCID/uPA mouse liver by HH has never been achieved and limits the broader application of these mice for other areas of biomedical research. The herpes simplex virus type-1 thymidine kinase (HSVtk)/ganciclovir (GCV) system is a powerful tool for cell-specific ablation in transgenic animals. The aim of this study was to selectively eliminate murine-derived parenchymal liver cells from humanized SCID/uPA mouse liver in order to achieve mice with completely humanized liver parenchyma. Thus, we reproduced the HSVtk (vTK)/GCV system of hepatic failure in SCID/uPA mice., Methodology/principal Findings: In vitro experiments demonstrated efficient killing of vTK expressing hepatoma cells after GCV treatment. For in vivo experiments, expression of vTK was targeted to the livers of FVB/N and SCID/uPA mice. Hepatic sensitivity to GCV was first established in FVB/N mice since these mice do not undergo liver failure inherent to SCID/uPA mice. Hepatic vTK expression was found to be an integral component of GCV-induced pathologic and biochemical alterations and caused death due to liver dysfunction in vTK transgenic FVB/N and non-transplanted SCID/uPA mice. In SCID/uPA mice with humanized liver, vTK/GCV caused death despite extensive replacement of the mouse liver parenchyma with HH (ranging from 32-87%). Surprisingly, vTK/GCV-dependent apoptosis and mitochondrial aberrations were also localized to bystander vTK-negative HH., Conclusions/significance: Extensive replacement of mouse liver parenchyma by HH does not provide a secure therapeutic advantage against vTK/GCV-induced cytotoxicity targeted to residual mouse hepatocytes. Functional support by engrafted HH may be secured by strategies aimed at limiting this bystander effect.

Recently, several groups have introduced expanded criteria for selection of patients with hepatocellular carcinoma (HCC) prior to transplant, but the exact number of potential newly recruited patients remains unclear. This registry-based study assessed 270 patients diagnosed with HCC. The potential number of transplant candidates was based on age (< or =65 years), absence of metastases and macro-vascular invasion, and on 12 previously published, expanded selection criteria. A wide range of increase in the number of transplant candidates was observed (12-63% when compared with the number of such candidates who would have been selected solely based on the Milan criteria). The most conservative criteria were Seoul (Kwon, 2007; increase of 12%), Valencia (Silva, 2008; 16%), total tumor volume/alpha-fetoprotein (Toso, 2009; 20%) and UCSF (Yao, 2007; 20%). This data will assist Centers and policy agencies in predicting the need for resources linked to an expansion of criteria.

Falciparum malaria is initiated when Anopheles mosquitoes transmit the Plasmodium sporozoite stage during a blood meal. Irradiated sporozoites confer sterile protection against subsequent malaria infection in animal models and humans. This level of protection is unmatched by current recombinant malaria vaccines. However, the live-attenuated vaccine approach faces formidable obstacles, including development of accurate, reproducible attenuation techniques. We tested whether Plasmodium falciparum could be attenuated at the early liver stage by genetic engineering. The P. falciparum genetically attenuated parasites (GAPs) harbor individual deletions or simultaneous deletions of the sporozoite-expressed genes P52 and P36. Gene deletions were done by double-cross-over recombination to avoid genetic reversion of the knockout parasites. The gene deletions did not affect parasite replication throughout the erythrocytic cycle, gametocyte production, mosquito infections, and sporozoite production rates. However, the deletions caused parasite developmental arrest during hepatocyte infection. The double-gene deletion line exhibited a more severe intrahepatocytic growth defect compared with the single-gene deletion lines, and it did not persist. This defect was assessed in an in vitro liver-stage growth assay and in a chimeric mouse model harboring human hepatocytes. The strong phenotype of the double knockout GAP justifies its human testing as a whole-organism vaccine candidate using the established sporozoite challenge model. GAPs might provide a safe and reproducible platform to develop an efficacious whole-cell malaria vaccine that prevents infection at the preerythrocytic stage.

Criteria for the selection of candidates for liver transplantation in the presence of hepatocellular carcinoma (HCC) should accurately predict posttransplant recurrence while not excluding excessive numbers of patients from candidacy. Existing criteria are challenged by the limited accuracy of radiological assessment. The total tumor volume (TTV) was calculated by the addition of the volume of each individual tumor. A preliminary analysis was carried out on HCC patient data from the Alberta Liver Transplant Program (52 patients) and then validated on the populations of the Universities of Toronto and Colorado programs (154 and 82 patients). A TTV cutoff of 115 cm(3) was chosen on the basis of the risk of recurrence with use of a receiver operating characteristic curve. Radiology correlated more closely to pathology with TTV than with Milan and University of California at San Francisco (UCSF) criteria (91% versus 69% and 75% of patients, P < 0.0001). Although more patients met qualifying criteria for transplant with TTV (28%-53% more than Milan and 16%-26% more than UCSF), no deterioration of outcome was demonstrated in an analysis of patients within TTV < or = 115 cm(3) in comparison with those meeting Milan or UCSF classifications at all institutions. Patients with TTV > 115 cm(3) experienced more recurrences and lower patient survival in the Alberta and Colorado series (P < 0.05). When TTV with a cutoff of 115 cm(3) is used for candidate selection, the accuracy of pretransplant radiological assessment is enhanced, with posttransplant outcomes not different from those achieved with Milan and UCSF classifications despite a more inclusive patient population.

A major problem in hepatitis C virus (HCV) immunotherapy or vaccine design is the extreme variability of the virus. We identified human monoclonal antibodies (mAbs) that neutralize genetically diverse HCV isolates and protect against heterologous HCV quasispecies challenge in a human liver-chimeric mouse model. The results provide evidence that broadly neutralizing antibodies to HCV protect against heterologous viral infection and suggest that a prophylactic vaccine against HCV may be achievable.

Human Leukocyte Antigen (HLA) antibodies posttransplant have been associated with an increased risk of early graft failure in kidney transplants. Whether this also applies to islet transplantation is not clear. To achieve insulin independence after islet transplants multiple donor infusions may be required. Hence, islet transplant recipients are at risk of sensitization after transplantation. Islet transplant recipients were screened for HLA antibodies posttransplant by flow-based methods. A total of 98 patients were studied. Twenty-nine patients (31%) developed de novo donor specific antibodies (DSA) posttransplant. Twenty-three patients developed DSA while on immunosuppression (IS). Among recipients who have discontinued IS, 10/14 (71%) are broadly sensitized with panel reactive antibody (PRA) >or=50%. The risk of becoming broadly sensitized after transplant was 11/69 (16%) if the recipient was unsensitized prior to transplant. The majority of these antibodies have persisted over time. Appearance of HLA antibodies posttransplant is concerning, and the incidence rises abruptly in subjects weaned completely from IS. This may negatively impact the ability of these individuals to undergo further islet, pancreas or kidney transplantation and should be discussed upfront during evaluation of candidates for islet transplantation.

ABO incompatible (ABO-In) liver transplant remains a controversial solution to acute liver failure in adults. Adult liver recipients with acute liver failure or severely decompensated end-stage disease, intubated and/or in the intensive care unit, were grouped as ABO-In (n = 14), ABO-compatible (n = 29, ABO-C) and ABO-identical (n = 65, ABO-Id). ABO-In received quadruple immunosuppression with antibody-depleting induction agents (except two), calcineurin inhibitors, antimetabolites and steroids. No significant difference of patient and graft survivals was observed among ABO-In, ABO-C and ABO-Id: graft survivals were 64%, 62% and 67%, respectively, in 1 year and 56%, 54% and 60%, respectively, in 5 years; patient survivals 86%, 69% and 67%, respectively, in 1 year and 77%, 61% and 62%, respectively, in 5 years. Three ABO-In grafts were lost (one hyper-acute rejection and two hepatic artery thrombosis). Surgical and infectious complications were similarly distributed between groups, except the hepatic artery thrombosis, more frequent in ABO-In (2, 14%) than ABO-I (1, 1.5%, P < 0.05). In contrast to previous studies, no significant difference of patient and graft survivals could be observed among all ABO-compatibility settings. Our results suggest that ABO-incompatible transplants should be viewed as an important therapeutic option in adult patients with acute liver failure awaiting an emergency procedure.

Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) is capable of inducing apoptosis in non-small cell lung carcinoma (NSCLC). However, many of the human NSCLC cell lines are resistant to TRAIL, and TRAIL treatment of the resistant cells leads to the activation of nuclear factor-kappaB (NF-kappaB) and extracellular signal-regulated kinase 1/2 (ERK1/2). TRAIL can induce apoptosis in TRAIL-sensitive NSCLC cells through the induction of death-inducing signaling complex (DISC) assembly in lipid rafts of plasma membrane. In the DISC, caspase-8 is cleaved and initiates TRAIL-induced apoptosis. In contrast, TRAIL-DISC assembly in the nonraft phase of the plasma membrane leads to the inhibition of caspase-8 cleavage and NF-kappaB and ERK1/2 activation in TRAIL-resistant NSCLC cells. Receptor-interacting protein (RIP) and cellular Fas-associated death domain-like interleukin-1beta-converting enzyme-inhibitory protein (c-FLIP) mediates the DISC assembly in nonrafts and selective knockdown of either RIP or c-FLIP with interfering RNA redistributes the DISC from nonrafts to lipid rafts, thereby switching the DISC signals from NF-kappaB and ERK1/2 activation to caspase-8-initiated apoptosis. Chemotherapeutic agents inhibit c-FLIP expression, thereby enhancing the DISC assembly in lipid rafts for caspase-8-initiated apoptosis. These studies indicate that RIP and c-FLIP-mediated assembly of the DISC in nonrafts is a critical upstream event in TRAIL resistance and thus targeting of either RIP or c-FLIP may lead to the development of novel therapeutic strategies that can overcome TRAIL resistance in human NSCLC.

The severe combined immunodeficiency disorder (SCID)-beige/albumin (Alb)-urokinase plasminogen activator (uPA) mouse containing a human-mouse chimeric liver is currently the only small animal model capable of supporting hepatitis C virus (HCV) infection. This model was utilized to characterize the host transcriptional response to HCV infection. The purpose of these studies was to investigate the genetic component of the host response to HCV infection and also to distinguish virus-induced gene expression changes from adaptive HCV-specific immune-mediated effects. Gene expression profiles from HCV-infected mice were also compared to those from HCV-infected patients. Analyses of the gene expression data demonstrate that host factors regulate the response to HCV infection, including the nature of the innate antiviral immune response. They also indicate that HCV mediates gene expression changes, including regulation of lipid metabolism genes, which have the potential to be directly cytopathic, indicating that liver pathology may not be exclusively mediated by HCV-specific adaptive immune responses. This effect appears to be inversely related to the activation of the innate antiviral immune response. In summary, the nature of the initial interferon response to HCV infection may determine the extent of viral-mediated effects on host gene expression.

Islet transplantation is being offered increasingly for selected patients with unstable type 1 diabetes. Percutaneous transhepatic portal access avoids a need for surgery, but is associated with potential risk of bleeding. Between 1999 and 2005, we performed 132 percutaneous transhepatic islet transplants in 67 patients. We encountered bleeding in 18/132 cases (13.6%). In univariate analysis, the risk of bleeding in the absence of effective track ablation was associated with an increasing number of procedures (2nd and 3rd procedures with an odds ratio (OR) of 9.5 and 20.9, respectively), platelets count <150,000 (OR 4.4), elevated portal pressure (OR 1.1 per mm Hg rise), heparin dose > or =45 U/kg (OR 9.8) and pre-transplant aspirin (81 mg per day) (OR 2.6, p = 0.05). A multivariate analysis further confirmed the cumulative transplant procedure number (p < 0.001) and heparin dose > or =45 U/kg (p = 0.02) as independent risk factors for bleeding. Effective mechanical sealing of the intrahepatic portal catheter tract with thrombostatic coils and tissue fibrin glue completely prevented bleeding in all subsequent procedures (n = 26, p = 0.02). We conclude that bleeding after percutaneous islet implantation is an avoidable complication provided the intraparenchymal liver tract is sealed effectively.

Sirolimus (SRL) has been used for most islet recipients over the past 5 years. It provides balanced immunosuppression in combination with low-dose calcineurin inhibitors, while avoiding corticosteroids. This regimen decreases the risk of nephrotoxicity, neurotoxicity and diabetogenicity. SRL has also been used selectively in clinical liver and kidney transplantation. A number of common side effects including anemia, leucopenia, thrombocytopenia, hypercholesterolemia, mouth ulceration, joint pain, extremity edema and impaired wound healing have been associated with the use of SRL. As SRL is used more frequently, evidence has been gathered on its rare but severe side effects. We report 2 patients who underwent islet transplantation and developed symptomatic small bowel ulceration that resolved after complete withdrawal of SRL. Although small bowel ulceration is rare, it can potentially progress to more serious complications if not treated adequately. Our experience highlights an uncommon but potentially serious adverse effect of high-dose SRL in islet recipients.

Posttransplant chronic renal failure, secondary to calcineurin inhibitor agents, is emerging as a major problem in liver transplantation. We report a randomized clinical trial comparing daclizumab, delayed low-dose tacrolimus (target trough level 4-8 ng/mL, starting day 4-6), Investigational Arm (n = 72), to standard tacrolimus induction/maintenance dosing, Standard Arm (n = 76), with mycophenolate mofetil and tapering corticosteroids in both study arms. The end-points were renal function indicated by the Modification of Diet in Renal Disease (MDRD). There was no significant difference in patient survival (86.6% Investigational Arm vs. 92.9% Standard Arm; P = 0.21) or acute rejection (23.2% vs. 27.7%, respectively; P = 0.68). Statistically significant differences in median glomerular filtration rate (GFR) were found in favor of the Investigational Arm. With the CG equation, the GFR at the end of the first week was 110.7 vs. 89.6 mL/min (P = 0.019) without significant differences thereafter. With the MDRD, statistically significant differences extended to the first posttransplant month (86.8 vs. 70.1 mL/min/1.73 m(2); P < 0.001) with and was seen at month 6 (75.4 vs. 69.5 mL/min/1.73 m(2); P = 0.038). In conclusion, delayed low-dose tacrolimus, in combination with daclizumab and mycophenolate mofetil, preserves early renal function post-liver transplantation without the cost of increased acute rejection.

Islet transplantation can restore endogenous beta-cell function to subjects with type 1 diabetes. Sixty-five patients received an islet transplant in Edmonton as of 1 November 2004. Their mean age was 42.9 +/- 1.2 years, their mean duration of diabetes was 27.1 +/- 1.3 years, and 57% were women. The main indication was problematic hypoglycemia. Forty-four patients completed the islet transplant as defined by insulin independence, and three further patients received >16,000 islet equivalents (IE)/kg but remained on insulin and are deemed complete. Those who became insulin independent received a total of 799,912 +/- 30,220 IE (11,910 +/- 469 IE/kg). Five subjects became insulin independent after one transplant. Fifty-two patients had two transplants, and 11 subjects had three transplants. In the completed patients, 5-year follow-up reveals that the majority ( approximately 80%) have C-peptide present post-islet transplant, but only a minority ( approximately 10%) maintain insulin independence. The median duration of insulin independence was 15 months (interquartile range 6.2-25.5). The HbA(1c) (A1C) level was well controlled in those off insulin (6.4% [6.1-6.7]) and in those back on insulin but C-peptide positive (6.7% [5.9-7.5]) and higher in those who lost all graft function (9.0% [6.7-9.3]) (P < 0.05). Those who resumed insulin therapy did not appear more insulin resistant compared with those off insulin and required half their pretransplant daily dose of insulin but had a lower increment of C-peptide to a standard meal challenge (0.44 +/- 0.06 vs. 0.76 +/- 0.06 nmol/l, P < 0.001). The Hypoglycemic score and lability index both improved significantly posttransplant. In the 128 procedures performed, bleeding occurred in 15 and branch portal vein thrombosis in 5 subjects. Complications of immunosuppressive therapy included mouth ulcers, diarrhea, anemia, and ovarian cysts. Of the 47 completed patients, 4 required retinal laser photocoagulation or vitrectomy and 5 patients with microalbuminuria developed macroproteinuria. The need for multiple antihypertensive medications increased from 6% pretransplant to 42% posttransplant, while the use of statin therapy increased from 23 to 83% posttransplant. There was no change in the neurothesiometer scores pre- versus posttransplant. In conclusion, islet transplantation can relieve glucose instability and problems with hypoglycemia. C-peptide secretion was maintained in the majority of subjects for up to 5 years, although most reverted to using some insulin. The results, though promising, still point to the need for further progress in the availability of transplantable islets, improving islet engraftment, preserving islet function, and reducing toxic immunosuppression.