Direct-acting antivirals are effective and safe in HCV/HIV-coinfected liver transplant recipients who experience recurrence of hepatitis C: A prospective nationwide cohort study.

Direct-acting antivirals have proved to be highly efficacious and safe in monoinfected liver transplant (LT) recipients who experience recurrence of hepatitis C virus (HCV) infection. However, there is a lack of data on effectiveness and tolerability of these regimens in HCV/HIV-coinfected patients who experience recurrence of HCV infection after LT. In this prospective, multicenter cohort study, the outcomes of 47 HCV/HIV-coinfected LT patients who received DAA therapy (with or without ribavirin [RBV]) were compared with those of a matched cohort of 148 HCV-monoinfected LT recipients who received similar treatment. Baseline characteristics were similar in both groups. HCV/HIV-coinfected patients had a median (IQR) CD4 T-cell count of 366 (256-467) cells/µL. HIV-RNA was <50 copies/mL in 96% of patients. The DAA regimens administered were SOF + LDV ± RBV (34%), SOF + SMV ± RBV (31%), SOF + DCV ± RBV (27%), SMV + DCV ± RBV (5%), and 3D (3%), with no differences between the groups. Treatment was well tolerated in both groups. Rates of SVR (negative serum HCV-RNA at 12 weeks after the end of treatment) were high and similar for coinfected and monoinfected patients (95% and 94%, respectively; P = .239). Albeit not significant, a trend toward lower SVR rates among patients with advanced fibrosis (P = .093) and genotype 4 (P = .088) was observed. In conclusion, interferon-free regimens with DAAs for post-LT recurrence of HCV infection in HIV-infected individuals were highly effective and well tolerated, with results comparable to those of HCV-monoinfected patients.

Molecular profiling of subclinical inflammatory lesions in long-term surviving adult liver transplant recipients.

BACKGROUND & AIMS: Subclinical inflammatory changes are commonly described in long-term transplant recipients undergoing protocol liver biopsies. The pathogenesis of these lesions remains unclear. The aim of this study was to identify the key molecular pathways driving progressive subclinical inflammatory liver allograft damage. METHODS: All liver recipients followed at Hospital Clínic Barcelona who were >10 years post-transplant were screened for participation in the study. Patients with recurrence of underlying liver disease, biliary or vascular complications, chronic rejection, and abnormal liver function tests were excluded. Sixty-seven patients agreed to participate and underwent blood and serological tests, transient elastography and a liver biopsy. Transcriptome profiling was performed on RNA extracted from 49 out of the 67 biopsies employing a whole genome next generation sequencing platform. Patients were followed for a median of 6.8 years following the index liver biopsy. RESULTS: Median time since transplantation to liver biopsy was 13 years (10-22). The most frequently observed histological abnormality was portal inflammation with different degrees of fibrosis, present in 45 biopsies (67%). Two modules of 102 and 425 co-expressed genes were significantly correlated with portal inflammation, interface hepatitis and portal fibrosis. These modules were enriched in molecular pathways known to be associated with T cell mediated rejection. Liver allografts showing the highest expression levels for the two modules recapitulated the transcriptional profile of biopsies with clinically apparent rejection and developed progressive damage over time, as assessed by non-invasive markers of fibrosis. CONCLUSIONS: A large proportion of adult liver transplant recipients who survive long-term exhibit subclinical histological abnormalities. The transcriptomic profile of these patients' liver tissue closely resembles that of T cell mediated rejection and may result in progressive allograft damage. LAY SUMMARY: A large proportion of adult liver transplant recipients who survive for a long time exhibit subclinical histological abnormalities. The expression profile (a measurement of the activity of genes) of liver tissue from a large fraction of these patients closely resembles the profile of T cell mediated rejection. Liver allografts showing the highest expression levels of rejection-related genes developed progressive damage over time.

Portal pressure and liver stiffness measurements in the prediction of fibrosis regression after sustained virological response in recurrent hepatitis C.

Sustained virological response (SVR) improves survival in post-liver transplant (LT) recurrent hepatitis C. However, the impact of SVR on fibrosis regression is not well defined. In addition, the performance of noninvasive methods to evaluate the presence of fibrosis and portal hypertension (PH) post-SVR has been scarcely evaluated. We aimed to investigate the degree of fibrosis regression (decrease ≥1 METAVIR stage) after-SVR and its associated factors in recurrent hepatitis C, as well as the diagnostic capacity of noninvasive methods in the assessment of liver fibrosis and PH after viral clearance. We evaluated 112 hepatitis C virus-infected LT recipients who achieved SVR between 2001 and 2015. A liver biopsy was performed before treatment and 12 months post-SVR. Hepatic venous pressure gradient (HVPG), liver stiffness measurement (LSM), and Enhanced Liver Fibrosis (ELF) score were also determined at the same time points. Sixty-seven percent of the cohort presented fibrosis regression: 43% in recipients with cirrhosis and 72%-85% in the remaining stages (P = 0.002). HVPG, LSM, and ELF significantly decreased post-SVR. Liver function significantly improved, and survival was significantly better in patients achieving fibrosis regression. Baseline HVPG and LSM as well as decompensations before therapy were independent predictors of fibrosis regression. One year post-SVR, LSM had a high diagnostic accuracy to discard the presence of advanced fibrosis (AF) and clinically significant PH (AUROC, 0.902 and 0.888). CONCLUSION: In conclusion, SVR post-LT induces fibrosis regression in most patients, leading to significant clinical benefits. Pretreatment HVPG and LSM are significant determinants of the likelihood of fibrosis regression. Finally, LSM accurately predicts the presence of AF and PH 1 year after SVR and thus can be used to determine monitoring strategies. (Hepatology 2018;67:1683-1694).

Human immunodeficiency virus-infected liver transplant recipients with incidental hepatocellular carcinoma: A prospective multicenter nationwide cohort study.

There is a lack of data on incidental hepatocellular carcinoma (iHCC) in the setting of liver transplantation (LT) in human immunodeficiency virus (HIV)-infected patients. This study aims to describe the frequency, histopathological characteristics, and outcomes of HIV+ LT recipients with iHCC from a Spanish multicenter cohort in comparison with a matched cohort of LT patients without HIV infection. A total of 15 (6%) out of 271 patients with HIV infection who received LT in Spain from 2002 to 2012 and 38 (5%) out of the 811 HIV- counterparts presented iHCC in liver explants (P = 0.58). Patients with iHCC constitute the present study population. All patients also had hepatitis C virus (HCV)-related cirrhosis. There were no significant differences in histopathological features of iHCC between the 2 groups. Most patients showed a small number and size of tumoral nodules, and few patients had satellite nodules, microvascular invasion, or poorly differentiated tumors. After a median follow-up of 49 months, no patient developed hepatocellular carcinoma (HCC) recurrence after LT. HIV+ LT recipients tended to have lower survival than their HIV- counterparts at 1 (73% versus 92%), 3 (67% versus 84%), and 5 years (50% versus 80%; P = 0.06). There was also a trend to a higher frequency of HCV recurrence as a cause of death in the former (33% versus 10%; P = 0.097). In conclusion, among LT recipients for HCV-related cirrhosis, the incidence and histopathological features of iHCC in HIV+ and HIV- patients were similar. However, post-LT survival was lower in HIV+ patients probably because of a more aggressive HCV recurrence. Liver Transplantation 23 645-651 2017 AASLD.

IFN-free therapy for HIV/HCV-coinfected patients within the liver transplant setting.

OBJECTIVES: IFN-based therapy against hepatitis C recurrence after liver transplantation (LT) has poor effectiveness and tolerability. In HIV/HCV-coinfected liver transplant recipients, the results are even poorer. Here, we report our experience using direct antiviral agents (DAAs) in 11 consecutive coinfected patients within the LT setting. METHODS: Four patients with compensated cirrhosis and hepatocellular carcinoma were treated while awaiting LT and seven patients received antiviral therapy due to severe hepatitis C recurrence after LT [fibrosing cholestatic hepatitis (n = 1), fibrosis stage ≥F3 (n = 2) and decompensated cirrhosis (n = 4)]. Patients were treated with different sofosbuvir-based regimens with or without ribavirin for 12 or 24 weeks. RESULTS: Sustained virological response (SVR) was achieved in all patients. Two of the four patients treated while awaiting LT reached the time of transplant with undetectable HCV-RNA that remained undetectable 12 weeks after LT, one patient had detectable HCV-RNA at the time of transplant but achieved SVR after completing 12 weeks of therapy after LT and the last patient is still on the waiting list. Seven patients with severe post-LT hepatitis C recurrence were treated within 11-120 months after LT. In these patients, viral eradication was associated with an improvement in liver function and clinical decompensation. Tolerance to antiviral therapy was good and only four patients reported mild adverse events. CONCLUSIONS: IFN-free regimens are effective and well tolerated in HIV/HCV-coinfected patients within the LT setting, but more data are needed to confirm our promising results and to establish the best treatment option in this population.

High expression of CD38, CD69, CD95 and CD154 biomarkers in cultured peripheral T lymphocytes correlates with an increased risk of acute rejection in liver allograft recipients.

The mayor goal still outstanding into the solid organ transplantation field involves the search of surrogate biomarkers able to predict several clinical events, such as acute rejection (AR) or opportunistic infection. In the present multicenter study, a series of interesting surface antigens with important activator or inhibitory immune functions on cultured peripheral T cells were monitored in liver transplant recipients drawn at baseline and up to one year after transplantation. Sixty-four patients were included in the multicenter study during 3 years. Pre- and post-transplantation surface antigens levels displayed significant differences between AR and non acute rejection (NAR) groups, and also this differential expression was used to construct a risk predictive model based on a composite panel of outcome biomarkers (CD38, CD69, CD95 and CD154). The model was able to stratify these patients at high risk of AR. These preliminary results could provide basic information to improve the immunosuppressive treatment and it might better help to predict AR episodes.

High frequency of central memory regulatory T cells allows detection of liver recipients at risk of early acute rejection within the first month after transplantation.

Several studies have analyzed the potential of T regulatory cells (Treg cells) as biomarkers of acute rejection (AR). The aim of the present multicenter study was to correlate the percentage of peripheral Treg cells in liver graft recipients drawn at baseline up to 12 months after transplantation with the presence of AR. The percentage of central memory (cm) Treg cells (CD4(+)CD25(high)CD45RO(+)CD62L(+)) was monitored at pre-transplant and at 1 and 2 weeks, and 1, 2, 3 and 6 months and 1 year post-transplantation. The same validation standard operating procedures were used in all participating centers. Fifteen patients developed AR (23.4%). Hepatitis C virus recurrence was observed in 16 recipients, who displayed low peripheral blood cmTreg levels compared with patients who did not. A steady increase of cmTregs was observed during the first month after transplantation with statistically significant differences between AR and non-AR patients. The high frequency of memory Treg cells allowed us to monitor rejection episodes during the first month post-transplantation. On the basis of these data, we developed a prediction model for assessing risk of AR that can provide clinicians with useful information for managing patients individually and customizing immunosuppressive therapies.

Human immunodeficiency virus infection does not worsen prognosis of liver transplantation for hepatocellular carcinoma.

UNLABELLED: The impact of human immunodeficiency virus (HIV) infection on patients undergoing liver transplantation (LT) for hepatocellular carcinoma (HCC) is uncertain. This study aimed to assess the outcome of a prospective Spanish nationwide cohort of HIV-infected patients undergoing LT for HCC (2002-2014). These patients were matched (age, gender, year of LT, center, and hepatitis C virus (HCV) or hepatitis B virus infection) with non-HIV-infected controls (1:3 ratio). Patients with incidental HCC were excluded. Seventy-four HIV-infected patients and 222 non-HIV-infected patients were included. All patients had cirrhosis, mostly due to HCV infection (92%). HIV-infected patients were younger (47 versus 51 years) and had undetectable HCV RNA at LT (19% versus 9%) more frequently than non-HIV-infected patients. No significant differences were detected between HIV-infected and non-HIV-infected recipients in the radiological characteristics of HCC at enlisting or in the histopathological findings for HCC in the explanted liver. Survival at 1, 3, and 5 years for HIV-infected versus non-HIV-infected patients was 88% versus 90%, 78% versus 78%, and 67% versus 73% (P = 0.779), respectively. HCV infection (hazard ratio = 7.90, 95% confidence interval 1.07-56.82) and maximum nodule diameter >3 cm in the explanted liver (hazard ratio = 1.72, 95% confidence interval 1.02-2.89) were independently associated with mortality in the whole series. HCC recurred in 12 HIV-infected patients (16%) and 32 non-HIV-infected patients (14%), with a probability of 4% versus 5% at 1 year, 18% versus 12% at 3 years, and 20% versus 19% at 5 years (P = 0.904). Microscopic vascular invasion (hazard ratio = 3.40, 95% confidence interval 1.34-8.64) was the only factor independently associated with HCC recurrence. CONCLUSIONS: HIV infection had no impact on recurrence of HCC or survival after LT. Our results support the indication of LT in HIV-infected patients with HCC.

Protective Effect of Intravenous High Molecular Weight Polyethylene Glycol on Fatty Liver Preservation.

Ischemia reperfusion injury (IRI) leads to significant tissue damage in liver surgery. Polyethylene glycols (PEGs) are water soluble nontoxic polymers that have proved their effectiveness against IRI. The objective of our study was to investigate the potential protective effects of intravenous administration of a high molecular weight PEG of 35 kDa (PEG 35) in steatotic livers subjected to cold ischemia reperfusion. In this study, we used isolated perfused rat liver model to assess the effects of PEG 35 intravenous administration after prolonged cold ischemia (24 h, 4°C) and after reperfusion (2 h, 37°C). Liver injury was measured by transaminases levels and mitochondrial damage was determined by confocal microscopy assessing mitochondrial polarization (after cold storage) and by measuring glutamate dehydrogenase activity (after reperfusion). Also, cell signaling pathways involved in the physiopathology of IRI were assessed by western blot technique. Our results show that intravenous administration of PEG 35 at 10 mg/kg ameliorated liver injury and protected the mitochondria. Moreover, PEG 35 administration induced a significant phosphorylation of prosurvival protein kinase B (Akt) and activation of cytoprotective factors e-NOS and AMPK. In conclusion, intravenous PEG 35 efficiently protects steatotic livers exposed to cold IRI.

Pegylated interferon plus ribavirin in HIV-infected patients with recurrent hepatitis C after liver transplantation: a prospective cohort study.

BACKGROUND & AIMS: The aim of this study was to evaluate the results of treatment with pegylated interferon and ribavirin for the recurrence of hepatitis C after liver transplantation in HCV/HIV-coinfected patients. METHODS: This was a prospective, multicentre cohort study, including 78 HCV/HIV-coinfected liver transplant patients who received treatment for recurrent hepatitis C. For comparison, we included 176 matched HCV-monoinfected patients who underwent liver transplantation during the same period of time at the same centres and were treated for recurrent hepatitis C. RESULTS: Antiviral therapy was discontinued prematurely in 56% and 39% (p = 0.016), mainly because of toxicity (22% and 11%, respectively; p=0.034). Sustained virological response (SVR) was achieved in 21% of the coinfected patients and in 36% of monoinfected patients (p = 0.013). For genotype 1, SVR rates were 10% and 33% (p = 0.002), respectively; no significant differences were observed for the other genotypes. A multivariate analysis based on the whole series identified HIV-coinfection as an independent predictor of lack of SVR (OR, 0.17; 95% CI, 0.06-0.42). Other predictors of SVR were donor age, pretreatment HCV viral load, HCV genotype, and early virological response. SVR was associated with a significant improvement in survival: 5-year survival after antiviral treatment was 79% for HCV/HIV-coinfected patients with SVR vs. 43% for those without (p = 0.02) and 92% vs. 60% in HCV-monoinfected patients (p < 0.001), respectively. CONCLUSIONS: The response to pegylated interferon and ribavirin was poorer in HCV/HIV-coinfected liver recipients, particularly those with genotype 1. However, when SVR was achieved, survival of coinfected patients increased significantly.

Outcome and management of HCV/HIV coinfection pre- and post-liver transplantation. A 2015 update.

Liver transplantation is increasingly performed in selected HIV-infected patients in most developed countries, with excellent results reported in patients with liver diseases unrelated to HCV. In contrast, survival in HCV/HIV-coinfected liver recipients is poorer than in HCV-monoinfected patients, due to more aggressive recurrence of HCV and consequent graft loss and death. Results from American, French, and Spanish cohort studies showed a 5-year survival rate of only 50-55%. Therefore, it is debated whether liver transplantation should be offered to HCV/HIV-coinfected patients. Studies have shown that the variables more consistently associated with poor outcome are: (1) the use of old or HCV-positive donors, (2) dual liver-kidney transplantation, (3) recipients with very low body mass index and (4) less site experience. However, the most effective factor influencing transplantation outcome is the successful treatment of HCV recurrence with anti-HCV. Survival is 80% in patients whose HCV infection resolves. Unfortunately, the rates of sustained virological response with pegylated-interferon plus ribavirin in coinfected recipients are low, particularly for genotype 1 (only 10%). Here we present a non-systematic review of the literature based on our own experience in different liver transplant scenarios. This review covers selection criteria in HIV-infected patients, pre- and post-LT management, donor selection, anti-HCV treatment, drug interactions with antiretrovirals and anti-HCV direct antiviral agents, hepatocellular carcinoma, and liver retransplantation. Recommendations are rated. Finally, we explain how the introduction of new effective and more tolerable direct antiviral agents may improve significantly the outcome of HCV/HIV-coinfected liver recipients.

Polyethylene glycol rinse solution: an effective way to prevent ischemia-reperfusion injury.

AIM: To test whether a new rinse solution containing polyethylene glycol 35 (PEG-35) could prevent ischemia-reperfusion injury (IRI) in liver grafts. METHODS: Sprague-Dawley rat livers were stored in University of Wisconsin preservation solution and then washed with different rinse solutions (Ringer's lactate solution and a new rinse solution enriched with PEG-35 at either 1 or 5 g/L) before ex vivo perfusion with Krebs-Heinseleit buffer solution. We assessed the following: liver injury (transaminase levels), mitochondrial damage (glutamate dehydrogenase activity), liver function (bile output and vascular resistance), oxidative stress (malondialdehyde), nitric oxide, liver autophagy (Beclin-1 and LCB3) and cytoskeleton integrity (filament and globular actin fraction); as well as levels of metalloproteinases (MMP2 and MMP9), adenosine monophosphate-activated protein kinase (AMPK), heat shock protein 70 (HSP70) and heme oxygenase 1 (HO-1). RESULTS: When we used the PEG-35 rinse solution, reduced hepatic injury and improved liver function were noted after reperfusion. The PEG-35 rinse solution prevented oxidative stress, mitochondrial damage, and liver autophagy. Further, it increased the expression of cytoprotective heat shock proteins such as HO-1 and HSP70, activated AMPK, and contributed to the restoration of cytoskeleton integrity after IRI. CONCLUSION: Using the rinse solution containing PEG-35 was effective for decreasing liver graft vulnerability to IRI.

Detección precoz, prevención y manejo de la insuficiencia renal en el trasplante hepático / Early detection, prevention and management of renal failure in liver transplantation

La insuficiencia renal es una complicación frecuente de la población con trasplante hepático que se asocia con una elevada morbimortalidad. Se han descrito múltiples factores de riesgo para el desarrollo de insuficiencia renal postrasplante hepático en los periodos pre y postrasplante hepático, así como en el propio momento del trasplante. Para reducir el impacto de la insuficiencia renal postrasplante hepático es necesaria una actitud activa para la identificación de los pacientes con factores de riesgo, la implementación de estrategias preventivas y la detección precoz del deterioro de la función renal. Tomando como base las evidencias publicadas y la experiencia clínica, el presente documento incluye recomendaciones para la monitorización de la función renal en los pacientes con trasplante hepático, la prevención y el manejo de la insuficiencia renal postrasplante hepático, y la derivación al nefrólogo. Asimismo, se actualizan las pautas inmunosupresoras probadas para la prevención o el control del deterioro de la función renal tras el trasplante hepático

Renal failure is a frequent complication in liver transplant recipients and is associated with increased morbidity and mortality. A variety of risk factors for the development of renal failure in the pre- and post-transplantation periods have been described, as well as at the time of surgery. To reduce the negative impact of renal failure in this population, an active approach is required for the identification of those patients with risk factors, the implementation of preventive strategies, and the early detection of progressive deterioration of renal function. Based on published evidence and on clinical experience, this document presents a series of recommendations on monitoring RF in LT recipients, as well as on the prevention and management of acute and chronic renal failure after LT and referral of these patients to the nephrologist. In addition, this document also provides an update of the various immunosuppressive regimens tested in this population for the prevention and control of post-transplantation deterioration of renal function

[Early detection, prevention and management of renal failure in liver transplantation]. / Detección precoz, prevención y manejo de la insuficiencia renal en el trasplante hepático.

Renal failure is a frequent complication in liver transplant recipients and is associated with increased morbidity and mortality. A variety of risk factors for the development of renal failure in the pre- and post-transplantation periods have been described, as well as at the time of surgery. To reduce the negative impact of renal failure in this population, an active approach is required for the identification of those patients with risk factors, the implementation of preventive strategies, and the early detection of progressive deterioration of renal function. Based on published evidence and on clinical experience, this document presents a series of recommendations on monitoring RF in LT recipients, as well as on the prevention and management of acute and chronic renal failure after LT and referral of these patients to the nephrologist. In addition, this document also provides an update of the various immunosuppressive regimens tested in this population for the prevention and control of post-transplantation deterioration of renal function.

HCV-induced immune responses influence the development of operational tolerance after liver transplantation in humans.

Pathogen-induced immune responses prevent the establishment of transplantation tolerance in experimental animal models. Whether this occurs in humans as well remains unclear. The development of operational tolerance in liver transplant recipients with chronic hepatitis C virus (HCV) infection allows us to address this question. We conducted a clinical trial of immunosuppression withdrawal in HCV-infected adult liver recipients to elucidate (i) the mechanisms through which allograft tolerance can be established in the presence of an ongoing inflammatory response and (ii) whether anti-HCV heterologous immune responses influence this phenomenon. Of 34 enrolled liver recipients, drug withdrawal was successful in 17 patients (50%). Tolerance was associated with intrahepatic overexpression of type I interferon and immunoregulatory genes and with an expansion of exhausted PD1/CTLA4/2B4-positive HCV-specific circulating CD8(+) T cells. These findings were already present before immunosuppression was discontinued and were specific for HCV infection. In contrast, the magnitude of HCV-induced proinflammatory gene expression and the breadth of anti-HCV effector T cell responses did not influence drug withdrawal outcome. Our data suggest that in humans, persistent viral infections exert immunoregulatory effects that could contribute to the restraining of alloimmune responses, and do not necessarily preclude the development of allograft tolerance.

The impact of the prevention strategies on the indirect effects of CMV infection in solid organ transplant recipients.

Transplant recipients receiving immunosuppressive therapy are at increased risk of active cytomegalovirus (CMV) infection and disease. Without appropriate prophylaxis, as many as 80% of solid organ transplant recipients may experience CMV infection. In addition to the direct effects of CMV, infection may be associated with a range of indirect effects, including an increase in risk of other infections, as well as a higher incidence of rejection, graft loss and death. The indirect effects of CMV infection can vary depending on the transplanted organ. For example, CMV-infected kidney transplant recipients may be at increased risk of cardiovascular disease and diabetes, while CMV infection in liver transplant recipients may potentiate hepatitis C infection and increase the risk of post-transplant lymphoproliferative disease. Indirect effects result from a number of pathological processes, including immune modulation and immunosuppression, generation of cytotoxic, pro-inflammatory responses, and smooth muscle proliferation. Prophylactic treatment with antiviral medication can reduce the risk of CMV disease, thereby improving graft survival and overall outcomes, particularly in kidney and heart transplant recipients. Antiviral prophylaxis should be considered for all patients at risk of CMV infection after solid organ transplantation. In this paper we review the main indirect effects of CMV infection in solid organ transplant recipients, and the impact of CMV prophylaxis on these effects.

Silent information regulator 1 protects the liver against ischemia-reperfusion injury: implications in steatotic liver ischemic preconditioning.

Ischemia-reperfusion (IR) injury is an important problem in liver surgery especially when steatosis is present. Ischemic preconditioning (PC) is the only surgical strategy that has been applied in patients with steatotic livers undergoing warm ischemia. Silent information regulator 1 (SIRT1) is a histone deacetylase that regulates various cellular processes. This study evaluates the SIRT1 implication in PC in fatty livers. Homozygous (Ob) Zucker rats were subjected to IR and IR + PC. An additional group treated with sirtinol or EX527 (SIRT1 inhibitors) before PC was also realized. Liver injury and oxidative stress were evaluated. SIRT1 protein levels and activity, as well as other parameters involved in PC protective mechanisms (adenosine monophosphate protein kinase, eNOS, HSP70, MAP kinases, apoptosis), were also measured. We demonstrated that the protective effect of PC was due in part to SIRT1 induction, as SIRT1 inhibition resulted in increased liver injury and abolished the beneficial mechanisms of PC. In this study, we report for the first time that SIRT1 is involved in the protective mechanisms induced by hepatic PC in steatotic livers.

Bortezomib enhances fatty liver preservation in Institut George Lopez-1 solution through adenosine monophosphate activated protein kinase and Akt/mTOR pathways.

OBJECTIVES: The aim of this study is to investigate the protective mechanisms induced by bortezomib added to Institut George Lopez (IGL)-1 preservation solution to protect steatotic livers against cold ischaemia reperfusion injury and to examine whether these mechanisms occur through the activation of adenosine monophosphate activated protein kinase (AMPK), Akt/mTOR pathways. METHODS: Steatotic livers from obese rats were preserved for 24 h (at 4 °C) in IGL-1 solution with or without bortezomib (100 nM) or pretreated with AMPK inhibitor adenine 9-α-D-arabinofuranoside and preserved in IGL-1 + bortezomib. Livers were then perfused for 2 h at 37 °C. Liver injury (alanine aminotransferase/aspartate aminotransferase) and function (bile production and vascular resistance) were measured. Also, Akt/mTOR, phosphorylated AMPK (pAMPK) and apoptosis were determined by Western blot analyses. KEY FINDINGS: Bortezomib addition to IGL-1 solution significantly reduced steatotic liver injury, improved graft function and decreased liver apoptosis. These benefits were diminished by the pretreatment of obese rats with AMPK inhibitor Ara. Western blot analyses showed a significant increase in pAMPK after ischaemia and reperfusion. We also observed a significant phosphorylation of Akt in IGL-1 +bortezomib group that, in turn, induced the phosphorylation of mTOR and glycogen synthase kinase 3ß. CONCLUSIONS: Bortezomib, at low and non toxic concentration, is a promising additive to IGL-1 solution for steatotic liver preservation. Its protective effect is due to the activation of AMPK and Akt/mTOR pathways.

Immunosuppression minimization vs. complete drug withdrawal in liver transplantation.

Despite the increase in long-term survival, liver transplant recipients still exhibit higher morbidity and mortality than the general population. This is in part attributed to the lifelong administration of immunosuppression and its associated side effects. Several studies reported in the last decades have evaluated the impact of immunosuppression minimization in liver transplant recipients, but results have been inconsistent due to the heterogeneity of study designs and insufficient sample sizes. On the other hand, complete immunosuppression withdrawal has proven to be feasible in approximately 20% of carefully selected liver transplant recipients, especially in older patients and those with longer duration after transplantation. The long-term risks and clinical benefits of this strategy, however, also need to be clarified. As a consequence, and despite the general perception that a large proportion of liver recipients are over-immunosuppressed, it is currently not possible to derive evidence-based guidelines on how to manage long-term immunosuppression to improve clinical outcomes. Large clinical trials of drug minimization and/or withdrawal focused on clinically-relevant long-term outcomes are required. Development of personalized medicine tools and a deeper understanding of the pathogenesis of idiopathic inflammatory graft lesions will be pre-requisites to achieve these goals.

Prospective multicenter clinical trial of immunosuppressive drug withdrawal in stable adult liver transplant recipients.

UNLABELLED: Lifelong immunosuppression increases morbidity and mortality in liver transplantation. Discontinuation of immunosuppressive drugs could lessen this burden, but the safety, applicability, and clinical outcomes of this strategy need to be carefully defined. We enrolled 102 stable liver recipients at least 3 years after transplantation in a single-arm multicenter immunosuppression withdrawal trial. Drugs were gradually discontinued over a 6 to 9-month period. The primary endpoint was the development of operational tolerance, defined as successful immunosuppressive drug cessation maintained for at least 12 months with stable graft function and no histopathologic evidence of rejection. Out of the 98 recipients evaluated, 57 rejected and 41 successfully discontinued all immunosuppressive drugs. In nontolerant recipients rejection episodes were mild and resolved over 5.6 months (two nontolerant patients still exhibited mild gradually improving cholestasis at the end of follow-up). In tolerant recipients no progressive clinically significant histological damage was apparent in follow-up protocol biopsies performed up to 3 years following drug withdrawal. Tolerance was independently associated with time since transplantation (odds ratio [OR] 1.353; P = 0.0001), recipient age (OR 1.073; P = 0.009), and male gender (OR 4.657; P = 0.016). A predictive model incorporating the first two clinical variables identified subgroups of recipients with very high (79%), intermediate (30%-38%), and very low (0%) likelihood of successful withdrawal. CONCLUSION: When conducted at late timepoints after transplantation, immunosuppression withdrawal is successful in a high proportion of carefully selected liver recipients. A combination of clinical parameters could be useful to predict the success of this strategy. Additional prospective studies are now needed to confirm these results and to validate clinically applicable diagnostic biomarkers.