Organ Donation from Patients with a Rare Disease is Often Safe: The Italian Guidelines

Although a disease is defined as rare when it has a prevalence of less than 1: 2000, the overall prevalence of rare diseases in the population is greater than 1%. Among potential organ donors, a similar frequency is observed. To date, guidelines have not been established, and operational decisions have been made empirically, case- by-case, based on the experience and expertise of clinicians. For this reason, the Italian Superior Health Council (CSS) has appointed a working Group to address "patients with a rare disease as potential organ donors", with the aim of devising recommendations for the management of transplant cases in which the donors have a rare disease. This group evaluated 493 diseases (10% of all rare diseases, including over 95% of patients with a rare disease) to deliver a technical report dealing with the suitability of organ donation and transplantation, with a focus on the organs most frequently used, including kidney, liver, heart, lung, and pancreas. This work has made it clear that a rare disease "per se" does not contraindicate organ donation at all. Indeed, in donors affected by a rare disease, almost 80% of the organs are suitable for transplantation, approximately 7% are unsuitable, and approximately 14% are suitable as non-standard with an acceptable risk. This article is protected by copyright. All rights reserved.

Epidemiology and successful containment of a carbapenem-resistant Enterobacteriaceae outbreak in a Southern Italian Transplant Institute

INTRODUCTION

Carbapenem-resistant enterobacteriaceae (CRE) infections are difficult to treat and pose a serious threat to solid organ transplant (SOT) recipients. At our institute we observed an infection burden in 2012.

METHODS

In order to contain the spread of CRE infections, we established a taskforce to implement guidelines suggested by the Centers for Disease Control and Prevention (CDC) for this type of outbreak. Here, we describe the epidemiology of the outbreak in our SOT population, and the effectiveness of such interventions, by comparing levels of CRE hospital-acquired infection (HAI) pre- and post-task force intervention (from January 2009 to December 2012, and from September 2013 to December 2016, respectively) through a linear regression model.

RESULTS

In this study, we included 933 patients who underwent a total of 1017 SOT procedures, 286 of whom had a CRE-positive culture (28.8%), of which 65 (22.7% of CRE positive) developed infection. One-year mortality post-SOT was significantly higher in patients with CRE infection. After the taskforce intervention, the CRE HAI rate in SOT showed a significant inverse trend (event rate: -1.28, CI -1.70 to 0.86; P < 0.01).

CONCLUSION

In the paucity of treatment options, the application of CDC measures in our SOT institute contributed significantly to containing CRE infections.

Digital liver biopsy: Bio-imaging of fatty liver for translational and clinical research

The rapidly growing field of functional, molecular and structural bio-imaging is providing an extraordinary new opportunity to overcome the limits of invasive liver biopsy and introduce a "digital biopsy" for in vivo study of liver pathophysiology. To foster the application of bio-imaging in clinical and translational research, there is a need to standardize the methods of both acquisition and the storage of the bio-images of the liver. It can be hoped that the combination of digital, liquid and histologic liver biopsies will provide an innovative synergistic tri-dimensional approach to identifying new aetiologies, diagnostic and prognostic biomarkers and therapeutic targets for the optimization of personalized therapy of liver diseases and liver cancer. A group of experts of different disciplines (Special Interest Group for Personalized Hepatology of the Italian Association for the Study of the Liver, Institute for Biostructures and Bio-imaging of the National Research Council and Bio-banking and Biomolecular Resources Research Infrastructure) discussed criteria, methods and guidelines for facilitating the requisite application of data collection. This manuscript provides a multi-Author review of the issue with special focus on fatty liver.

Epithelial cell adhesion molecule fragments and signaling in primary human liver cells

Epithelial Cell Adhesion Molecule (EpCAM), or CD326, is a trans-membrane glycoprotein expressed by multiple normal epithelia as well as carcinoma. Human hepatic stem cells and bile duct epithelium of the liver are EpCAM positive. In tumor cell lines, its intracellular domain can be released after cleavage of the extracellular domain. Within the cell nucleus, it induces cell proliferation, but cleavage depends on cell contact. Fragments of various lengths have been described in tumor cells. Despite its described important role in proliferation in tumor cells, there is not much known about the expression and role of EpCAM fragments in primary human liver cells. Here, we demonstrate that EpCAM protein fragments and function are considerable different between tumor cells, normal fetal and adult liver cells. Contrary to previously reported findings in tumor cells, gene knockdown or treatment with an inhibitor of the cleavage enzyme ADAM17 (TACE) rather increased cell numbers in primary human fetal liver-derived EpCAM-positive cells. EpCAM fragment sizes were not affected by treatment with inhibitor. Knockdown of EPCAM gene expression by siRNA in sorted cells did not significantly affect proliferation-associated genes or cell numbers. The intracellular domain could not be detected within cell nuclei of fetal and adult liver cells. In conclusion, signaling through the intracellular domain of EpCAM appears to be a mechanism that induces proliferation specifically in tumorigenic cells but not in normal primary EpCAM-positive liver cells.

A matched pair analysis of multicenter longterm follow-up after split-liver transplantation with extended right grafts

Split-liver transplantation has been proposed as an alternative to whole liver (WL) transplantation to expand the donor pool, but studies comparing adult longterm outcomes between the 2 methods are conflicting and limited. This is the first Italian multicenter study that retrospectively analyzed 119 matched-pair recipients of whole and extended right grafts (ERGs) for longterm survival outcomes. In the overall population, WL recipients showed higher patient survival at 1 (93% versus 73%), 5 (87% versus 65%), and 10 years (83% versus 60%) after transplantation compared with split-liver recipients (P < 0.001); graft survivals of WL recipients were also superior at 1 (90% versus 76%), 5 (84% versus 57%), and 10 years (81% versus 52%) posttransplant (P < 0.001). However, among the 81 matched pairs that survived the first posttransplant year, 5- and 10-year patient survivals were 90% and 81% for split recipients and 99% and 96% for whole recipients, respectively (P = 0.34). The 5- and 10-year graft survivals were also comparable: 87% and 77% for split recipients, and 86% and 82% for whole recipients (P = 0.86). Cox regression analysis identified donor age >50, donor-to-recipient weight ratio < 1, retransplantation status, and United Network for Organ Sharing I-IIA status as risk factors for partial graft use. There were no significant differences in 5-year outcomes based on center volume. In conclusion, we demonstrate that adult liver transplantation with ERGs can achieve longterm success comparable with that of whole grafts in appropriate patients but should be selectively used in patients with risk factors. Liver Transplantation 23 1384-1395 2017 AASLD.

Response of Human Fetal Liver Progenitor Cell Types to Temperature and pH Stresses In Vitro

Prolonged physiological stresses, including abnormal pH and temperature, are deleterious. However, human hepatic progenitors have been shown to be quite tolerant of temporary temperature stress such as in cold ischemia. We aimed at identifying how various stresses affect liver progenitors, and at determining whether distinct effects exist on different progenitor cells of the human liver. Total fetal liver cells were exposed to low (25°C), normal (37°C), or high (40°C) temperatures, or low (6.76), normal (7.35), or high (7.88) pH in vitro. Culture at 25°C increased cell numbers and percentages of proliferation marker Ki67⁺ total cells. In total cell cultures, percentages of CD326⁺ hepatic progenitors co-expressing DLK1 (delta-like 1 homolog), SSEA4, or CD90 increased, as well as proliferation of SSEA4⁺ and CD235a⁺ progenitors. Analyses of presorted hepatic progenitors revealed that culture at 25°C increased cell numbers of CD326⁺ hepatic stem/progenitor cells but not DLK⁺ hepatoblasts. The expression of several mesenchymal genes was reduced, and distinct hepatic stem/progenitor cell colonies emerged. At 40°C, numbers of adherent hepatic cells decreased but those of hematopoietic nonadherent cells increased. High pH did not cause major effects. Acidic pH resulted in decreased total cell numbers and affected hematopoietic cells. Percentages of DLK1⁺ hepatoblasts were increased, but those of hematopoietic mature CD45⁺ cells were decreased. In particular, proliferation of adherent hepatic CD326⁺, SSEA4⁺ progenitors, and hematopoietic CD45⁺ cells and CD235a⁺ erythroblasts was reduced. Conclusively, our data indicate that low-temperature stress stimulates hepatic progenitor and erythroblast proliferation, whereas acidic pH promotes hepatic maturation and reduces hematopoietic cells.

HCV replication in gastrointestinal mucosa: Potential extra-hepatic viral reservoir and possible role in HCV infection recurrence after liver transplantation

PURPOSE

Hepatitis C virus (HCV) predominantly infects hepatocytes, although it is known that receptors for viral entry are distributed on a wide array of target cells. Chronic HCV infection is indeed characterized by multiple non-liver manifestations, suggesting a more complex HCV tropism extended to extrahepatic tissues and remains to be fully elucidated. In this study, we investigated the gastrointestinal mucosa (GIM) as a potential extrahepatic viral replication site and its contribution to HCV recurrence.

METHODS

We analyzed GIM biopsies from a cohort of 76 patients, 11 of which were HCV-negative and 65 HCV-positive. Of these, 54 biopsies were from liver-transplanted patients. In 29 cases, we were able to investigate gastrointestinal biopsies from the same patient before and after transplant. To evaluate the presence of HCV, we looked for viral antigens and genome RNA, whilst to assess viral replicative activity, we searched for the replicative intermediate minus-strand RNA. We studied the genetic diversity and the phylogenetic relationship of HCV quasispecies from plasma, liver and gastrointestinal mucosa of HCV-liver-transplanted patients in order to assess HCV compartmentalization and possible contribution of gastrointestinal variants to liver re-infection after transplantation.

RESULTS

Here we show that HCV infects and replicates in the cells of the GIM and that the favorite hosts were mostly enteroendocrine cells. Interestingly, we observed compartmentalization of the HCV quasispecies present in the gastrointestinal mucosa compared to other tissues of the same patient. Moreover, the phylogenetic analysis revealed a high similarity between HCV variants detected in gastrointestinal mucosa and those present in the re-infected graft.

CONCLUSIONS

Our results demonstrated that the gastrointestinal mucosa might be considered as an extrahepatic reservoir of HCV and that could contribute to viral recurrence. Moreover, the finding that HCV infects and replicates in neuroendocrine cells opens new perspectives on the role of these cells in the natural history of HCV infection.

End-Stage Organ Failure: Will Regenerative Medicine Keep its Promise?

End-stage organ failure is a major cause of death worldwide that can occur in patients of all ages and transplantation is the current standard of care for chronic end-stage disease of many organs. Despite the success of organ transplantation, it is becoming clear that there will never be enough organs made available through donation to meet the increasing demand. The past decade's rapid advancement in stem cell biology and tissue engineering generated an explosive outburst of reports that gave rise to regenerative medicine, a new field that promises to “fix” damaged organs through regeneration provided by transplanted cells, stimulation of endogenous repair mechanisms, or implantation of bioengineered tissue. Whether, and if so when, regenerative medicine will keep its promise is uncertain. As we continue to strive to find new effective solutions, alternative approaches based on the development of targeted, preventive interventions aimed at maintaining normal organ function, instead of repairing organ damage, should also be pursued.

Donor safety in living donor liver donation: An Italian multicenter survey

Major concerns about donor morbidity and mortality still limit the use of living donor liver transplantation (LDLT) to overcome the organ shortage. The present study assessed donor safety in LDLT in Italy reporting donor postoperative outcomes in 246 living donation procedures performed by 7 transplant centers. Outcomes were evaluated over 2 time periods using the validated Clavien 5-tier grading system, and several clinical variables were analyzed to determine the risk factors for donor morbidity. Different grafts were obtained from the 246 donor procedures (220 right lobe, 10 left lobe, and 16 left lateral segments). The median follow-up after donation was 112 months. There was no donor mortality. One or more complications occurred in 82 (33.3%) donors, and 3 of them had intraoperative complications (1.2%). Regardless of graft type, the rate of major complications (grade ≥ 3) was 12.6% (31/246). The overall donor morbidity and the rate of major complications did not differ significantly over time: 26 (10.6%) donors required hospital readmission throughout the follow-up period, whereas 5 (2.0%) donors required reoperation. Prolonged operative time (>400 minutes), intraoperative hypotension (systolic < 100 mm Hg), vascular abnormalities, and intraoperative blood loss (>300 mL) were multivariate risk factors for postoperative donor complications. In conclusion, from the standpoint of living donor surgery, a meticulous and well-standardized technique that reduces operative time and prevents blood loss and intraoperative hypotension may reduce the incidence of donor complications. Transparency in reporting results after LDLT is mandatory, and we should continue to strive for zero donor mortality. Liver Transplantation 23 184-193 2017 AASLD.

Transplantation of hepatocytes from genetically engineered pigs into baboons

BACKGROUND

Some patients with acute or acute-on-chronic hepatic failure die before a suitable human liver allograft becomes available. Encouraging results have been achieved in such patients by the transplantation of human hepatocyte progenitor cells from fetal liver tissue. The aim of the study was to explore survival of hepatocytes from genetically engineered pigs after direct injection into the spleen and other selected sites in immunosuppressed baboons to monitor the immune response and the metabolic function and survival of the transplanted hepatocytes.

METHODS

Baboons (n=3) were recipients of GTKO/hCD46 pig hepatocytes. All three baboons received anti-thymocyte globulin (ATG) induction and tapering methylprednisolone. Baboon 1 received maintenance immunosuppressive therapy with tacrolimus and rapamycin. Baboons 2 and 3 received an anti-CD40mAb/rapamycin-based regimen that prevents sensitization to pig solid organ grafts. The baboons were euthanized 4 or 5 weeks after hepatocyte transplantation. The baboon immune response was monitored by the measurement of anti-non-Gal IgM and IgG antibodies (by flow cytometry) and CFSE-mixed lymphocyte reaction. Monitoring for hepatocyte survival and function was by (i) real-time PCR detection of porcine DNA, (ii) real-time PCR for porcine gene expression, and (iii) pig serum albumin levels (by ELISA). The sites of hepatocyte injection were examined microscopically.

RESULTS

Detection of porcine DNA and porcine gene expression was minimal at all sites of hepatocyte injection. Serum levels of porcine albumen were very low-500-1000-fold lower than in baboons with orthotopic pig liver grafts, and approximately 5000-fold lower than in healthy pigs. No hepatocytes or infiltrating immune cells were seen at any of the injection sites. Two baboons (Baboons 1 and 3) demonstrated a significant increase in anti-pig IgM and an even greater increase in IgG, indicating sensitization to pig antigens.

DISCUSSION AND CONCLUSIONS

As a result of this disappointing experience, the following points need to be considered. (i) Were the isolated pig hepatocytes functionally viable? (ii) Are pig hepatocytes more immunogenic than pig hearts, kidneys, artery patch grafts, or islets? (iii) Does injection of pig cells (antigens) into the spleen and/or lymph nodes stimulate a greater immune response than when pig tissues are grafted at other sites? (iv) Did the presence of the recipient's intact liver prevent survival and proliferation of pig hepatocytes? (v) Is pig CD47-primate SIRP-α compatibility essential? In conclusion, the transplantation of genetically engineered pig hepatocytes into multiple sites in immunosuppressed baboons was associated with very early graft failure. Considerable further study is required before clinical trials should be undertaken.

Severe Acute Respiratory Failure due to Inhalation of Baby Powder and Successfully Treated with Venous-Venous Extracorporeal Membrane Oxygenation

Accidental inhalation of powder is a potential problem for infants. The clinical effects of inhaling powder depend on the powder contents, degree of aspiration, and the child's underlying systemic response. We present a case of accidental inhalation of rice starch powder in a 17-month-old girl, which led to severe acute respiratory distress syndrome responsive to conventional treatment, ultimately requiring venous-venous extracorporeal membrane oxygenation.

Response of Primary Human Bone Marrow Mesenchymal Stromal Cells and Dermal Keratinocytes to Thermal Printer Materials In Vitro

Advancement in thermal three-dimensional printing techniques has greatly increased the possible applications of various materials in medical applications and tissue engineering. Yet, potential toxic effects on primary human cells have been rarely investigated. Therefore, we compared four materials commonly used in thermal printing for bioengineering, namely thermally printed acrylonitrile butadiene styrene, MED610, polycarbonate, and polylactic acid, and investigated their effects on primary human adult skin epidermal keratinocytes and bone marrow mesenchymal stromal cells (BM-MSCs) in vitro. We investigated indirect effects on both cell types caused by potential liberation of soluble substances from the materials, and also analyzed BM-MSCs in direct contact with the materials. We found that even in culture without direct contact with the materials, the culture with MED610 (and to a lesser extent acrylonitrile butadiene styrene) significantly affected keratinocytes, reducing cell numbers and proliferation marker Ki67 expression, and increasing glucose consumption, lactate secretion, and expression of differentiation-associated genes. BM-MSCs had decreased metabolic activity, and exhibited increased cell death in direct culture on the materials. MED610 and acrylonitrile butadiene styrene induced the strongest expression of genes associated to differentiation and estrogen receptor activation. In conclusion, we found strong cell-type-specific effects of the materials, suggesting that materials for applications in regenerative medicine should be carefully selected not only based on their mechanical properties but also based on their cell-type-specific biological effects.

Circulatory response to volume expansion and transjugular intrahepatic portosystemic shunt in refractory ascites: Relationship with diastolic dysfunction

BACKGROUND

Cirrhotic cardiomyopathy may lead to heart failure in stressful circumstances, such as after transjugular intrahepatic portosystemic shunt (TIPS) placement.

AIM

To examine whether acute volume expansion predicts haemodynamic changes after TIPS and elicits signs of impending heart failure.

METHODS

We prospectively evaluated refractory ascites patients (group A) and compensated cirrhotics (group B), who underwent echocardiography, NT-proBNP measurement, and heart catheterization before and after volume load; group A repeated measurements after TIPS.

RESULTS

15 patients in group A (80% male; 54±12.4 years) and 8 in group B (100% male; 56±6.2 years) were enrolled. Echocardiography disclosed diastolic dysfunction in 30% and 12.5%, respectively. In group A, volume load and TIPS induced a significant increase in right atrial, mean pulmonary, capillary wedge pressure and cardiac index, and a decrease in systemic vascular resistance (respectively, 4.7±2.8 vs. 9.9±3.6 mmHg; 13.3±3.5 vs. 21.9±5.9 mmHg; 8.3±3.4 vs. 15.4±4.7 mmHg; 3.7±0.7 vs. 4.6±11 t/min/m2; 961±278 vs. 767±285 dynscm(-5); and 10.1±3.3 vs. 14.2±3.4 mmHg; 17.5±4 vs. 25.2±4.2 mmHg; 12.3±4 vs. 19.3±3.4 mmHg; 3.4±0.8 vs. 4.5±0.91l t/min/m2; 779±62 vs. 596±199 dynscm(-5), p<0.001 for all pairs). At 24h, cardiopulmonary pressures returned towards baseline.

CONCLUSIONS

Acute volume expansion predicted haemodynamic changes immediately after TIPS. All patients had adequate haemodynamic adaptation to TIPS; none developed signs of heart failure.

Long-Term Structural and Functional Myocardial Adaptations in Healthy Living Kidney Donors: A Pilot Study

BACKGROUND AND AIMS

Compensatory renal hypertrophy following unilateral nephrectomy (UNX) occurs in the remaining kidney. However, the long-term cardiac adaptive process to UNX remains poorly defined in humans. Our goal was to characterize myocardial structure and function in living kidney donors (LKDs), approximately 12 years after UNX.

METHODS AND RESULTS

Cardiac function and structure in 15 Italian LKDs, at least 5 years after UNX (median time from donation = 8.4 years) was investigated and compared to those of age and sex matched U.S. citizens healthy controls (n = 15). Standard and speckle tracking echocardiography (STE) was performed in both LKDs and controls. Plasma angiotensin II, aldosterone, atrial natriuretic peptide (ANP), N terminus pro B-type natriuretic peptide (NT-proBNP), cyclic guanylyl monophosphate (cGMP), and amino-terminal peptide of procollagen III (PIIINP) were also collected. Median follow-up was 11.9 years. In LKDs, LV geometry and function by STE were similar to controls, wall thickness and volumes were within normal limits also by CMR. In LKDs, CMR was negative for myocardial fibrosis, but apical rotation and LV torsion obtained by STE were impaired as compared to controls (21.4 ± 7.8 vs 32.7 ± 8.9 degrees, p = 0.04). Serum creatinine and PIIINP levels were increased [1.1 (0.9-1.3) mg/dL, and 5.8 (5.4-7.6)] μg/L, respectively), while urinary cGMP was reduced [270 (250-355) vs 581 (437-698) pmol/mL] in LKDs. No LKD developed cardiovascular or renal events during follow-up.

CONCLUSIONS

Long-term kidney donors have no apparent structural myocardial abnormalities as assessed by contrast enhanced CMR. However, myocardial deformation of the apical segments, as well as apical rotation, and LV torsion are reduced. The concomitant increase in circulating PIIINP level is suggestive of fibrosis. Further studies, focused on US and EU patients are warranted to evaluate whether these early functional modifications will progress to a more compromised cardiac function and structure at a later time.

Outcome of Transplantation Using Organs From Donors Infected or Colonized With Carbapenem-Resistant Gram-Negative Bacteria

Donor-derived infections due to multidrug-resistant bacteria are a growing problem in solid organ transplantation, and optimal management options are not clear. In a 2-year period, 30/214 (14%) recipients received an organ from 18/170 (10.5%) deceased donors with infection or colonization caused by a carbapenem-resistant gram-negative bacteria that was unknown at the time of transplantation. Among them, 14/30 recipients (47%) received a transplant from a donor with bacteremia or with infection/colonization of the transplanted organ and were considered at high risk of donor-derived infection transmission. The remaining 16/30 (53%) recipients received an organ from a nonbacteremic donor with colonization of a nontransplanted organ and were considered at low risk of infection transmission. Proven transmission occurred in 4 of the 14 high-risk recipients because donor infection was either not recognized, underestimated, or not communicated. These recipients received late, short or inappropriate posttransplant antibiotic therapy. Transmission did not occur in high-risk recipients who received appropriate and prompt antibiotic therapy for at least 7 days. The safe use of organs from donors with multidrug-resistant bacteria requires intra- and inter-institutional communication to allow appropriate management and prompt treatment of recipients in order to avoid transmission of infection.

Phases I-II Matched Case-Control Study of Human Fetal Liver Cell Transplantation for Treatment of Chronic Liver Disease

Fetal hepatocytes have a high regenerative capacity. The aim of the study was to assess treatment safety and clinical efficacy of human fetal liver cell transplantation through splenic artery infusion. Patients with endstage chronic liver disease on the waiting list for liver transplantation were enrolled. A retrospectively selected contemporary matched-pair group served as control. Nonsorted raw fetal liver cell preparations were isolated from therapeutically aborted fetuses. The end points of the study were safety and improvement of the Model for End-Stage Liver Disease (MELD) and Child-Pugh scores. Nine patients received a total of 13 intrasplenic infusions and were compared with 16 patients on standard therapy. There were no side effects related to the infusion procedure. At the end of follow-up, the MELD score (mean ± SD) in the treatment group remained stable from baseline (16.0 ± 2.9) to the last observation (15.7 ± 3.8), while it increased in the control group from 15.3 ± 2.5 to 19 ± 5.7 ( p = 0.0437). The Child-Pugh score (mean ± SD) dropped from 10.1 ± 1.5 to 9.1 ± 1.4 in the treatment group and increased from 10.0 ± 1.2 to 11.1 ± 1.6 in the control group ( p = 0.0076). All treated patients with history of recurrent portosystemic encephalopathy (PSE) had no further episodes during 1-year follow-up. No improvement was observed in the control group patients with PSE at study inclusion. Treatment was considered a failure in six of the nine patients (three deaths not liver related, one liver transplant, two MELD score increases) compared with 14 of the 16 patients in the control group (six deaths, five of which were caused by liver failure, four liver transplants, and four MELD score increases). Intrasplenic fetal liver cell infusion is a safe and well-tolerated procedure in patients with end-stage chronic liver disease. A positive effect on clinical scores and on encephalopathy emerged from this preliminary study.

Role of transcription factor CCAAT/enhancer-binding protein alpha in human fetal liver cell types in vitro

AIM

The transcription factor CCAAT/enhancer-binding protein alpha (C/EBPα) has been shown to play an important role in liver development, cell proliferation and differentiation. It is, however, largely unknown if C/EBPα regulates cell differentiation and proliferation differently in the diverse cell types of the human liver. We investigated the role of C/EBPα in primary human fetal liver cells and liver cell subpopulations in vitro using a 3-D perfusion bioreactor as an advanced in vivo-like human organ culture model.

METHODS

Human fetal liver cells were investigated in vitro. C/EBPα gene expression was knocked down using siRNA or overexpressed by plasmid transfection. Cell type-specific gene expression was studied, cell populations and their proliferation were investigated, and metabolic parameters were analyzed.

RESULTS

When C/EBPα gene expression was knocked down, we observed a significantly reduced expression of typical endothelial, hematopoietic and mesenchymal genes such as CD31, vWF, CD90, CD45 and α-smooth muscle actin in fetal cells. The intracellular expression of hepatic proteins and genes for liver-specific serum proteins α-fetoprotein and albumin were reduced, their protein secretion was increased. Fetal endothelial cell numbers were reduced and hepatoblast numbers were increased. C/EBPα overexpression in fetal cells resulted in increased endothelial numbers, but did not affect mesenchymal cell types or hepatoblasts.

CONCLUSION

We demonstrated that the effects of C/EBPα are specific for the different human fetal liver cell types, using an advanced 3-D perfusion bioreactor as a human in vivo-like model.

Experimental hepatocyte xenotransplantation--a comprehensive review of the literature

Hepatocyte transplantation (Tx) is a potential therapy for certain diseases of the liver, including hepatic failure. However, there is a limited supply of human livers as a source of cells and, after isolation, human hepatocytes can be difficult to expand in culture, limiting the number available for Tx. Hepatocytes from other species, for example, the pig, have therefore emerged as a potential alternative source. We searched the literature through the end of 2014 to assess the current status of experimental research into hepatocyte xenoTx. The literature search identified 51 reports of in vivo cross-species Tx of hepatocytes in a variety of experimental models. Most studies investigated the Tx of human (n = 23) or pig (n = 19) hepatocytes. No studies explored hepatocytes from genetically engineered pigs. The spleen was the most common site of Tx (n = 23), followed by the liver (through the portal vein [n = 6]) and peritoneal cavity (n = 19). In 47 studies (92%), there was evidence of hepatocyte engraftment and function across a species barrier. The data provided by this literature search strengthen the hypothesis that xenoTx of hepatocytes is feasible and potentially successful as a clinical therapy for certain liver diseases, including hepatic failure. By excluding vascular structures, hepatocytes isolated from genetically engineered pig livers may address some of the immunological problems of xenoTx.

Characterization of Liver-Specific Functions of Human Fetal Hepatocytes in Culture

This study was designed to assess liver-specific functions of human fetal liver cells proposed as a potential source for hepatocyte transplantation. Fetal liver cells were isolated from livers of different gestational ages (16-22 weeks), and the functions of cell preparations were evaluated by establishing primary cultures. We observed that 20- to 22-week-gestation fetal liver cell cultures contained a predominance of cells with hepatocytic traits that did not divide in vitro but were functionally competent. Fetal hepatocytes performed liver-specific functions at levels comparable to those of their adult counterpart. Moreover, exposure to dexamethasone in combination with oncostatin M promptly induced further maturation of the cells through the acquisition of additional functions (i.e., ability to store glycogen and uptake of indocyanine green). In some cases, particularly in cultures obtained from fetuses of earlier gestational ages (16-18 weeks gestation), cells with mature hepatocytic traits proved to be sporadic, and the primary cultures were mainly populated by clusters of proliferating cells. Consequently, the values of liver-specific functions detected in these cultures were low. We observed that a low cell density culture system rapidly prompted loss of the mature hepatocytic phenotype with downregulations of all the liver-specific functions. We found that human fetal liver cells can be cryopreserved without significant loss of viability and function and evaluated up to 1 year in storage in liquid nitrogen. They might, therefore, be suitable for cell banking and allow for the transplantation of large numbers of cells, thus improving clinical outcomes. Overall, our results indicate that fetal hepatocytes could be used as a cell source for hepatocyte transplantation. Fetal liver cells have been used so far to treat end-stage liver disease. Additional studies are needed to include these cells in cell-based therapies aimed to treat liver failure and inborn errors of metabolism.

IL28B polymorphisms of both recipient and donor cooperate to influence IFN treatment response in HCV recurrence after liver transplantation, but IL28B SNPs of the recipient play a major role in IFN-induced blocking of HCV replication

Single nucleotide polymorphisms (SNPs) of the IL28B locus are associated with a positive response to pegylated interferon-alpha and ribavirin (pegIFN-alpha/RBV) treatment of HCV-infected patients. This study evaluated the association between SNPs rs12980275, rs12979860 and rs8099917 and treatment outcome of HCV recurrent infection in HCV-positive patients who underwent liver transplant. We aimed to assess to what extent recipient and/or graft donor IL28B polymorphisms contribute to HCV clearance after transplantation influencing the response to the antiviral treatment. We found that the allele frequencies in donors were in agreement with the pattern expected in the European population. The frequency of favourable genotypes was significantly lower in recipients than in donors, reasonably because the recipients represented a group of patients affected by chronic Hepatitis C. Our study demonstrated that the positive outcome of the pegIFN-alpha/RBV treatment of HCV recurrence is associated with the co-presence of favourable genotypes of both donors and recipients. However, IL28B SNPs of the recipient seem to play a major role in this clinical setting. In particular, homozygosis of rs12979860 favourable genotype in recipients was associated with sustained virological response independently from the donor's genotype. Thus, identification of these SNPs may be useful to predict the response to IFN-based therapy of HCV recurrent infection in liver-transplanted patients.

ISMETT: An International Collaboration on Organ Transplantation

The Institute of the Mediterranean for Transplantation and High Specialty Therapies (ISMETT) is a multi-organ transplant and high specialty center located in Palermo, Italy and managed by the University of Pittsburgh Medical Center. Clinical transplant activity started in 1999 and, herein, we illustrate the outcomes achieved over the past 15 years. In total, ISMETT has performed 997 liver transplants (83.9% adults, 16.1% pediatrics) with a significant percentage of liver transplants from cadaver split livers (17%) and partial grafts from living donors (11.5%). Among liver transplant recipients, the overall five-year graft survival was 74.3% in the adult population and 79% in the pediatric population. ISMETT has also performed 419 kidney transplants in total: 211 from cadaveric donors (22 double), 176 from living donors, and 32 combined (19 with liver, 11 with pancreas, and 2 with heart). The 5-year renal graft survival was 82.2% (cadaveric donor) and 92.2% (living donor). More recently, in 2005, ISMETT started pancreas, lung, and heart transplant programs. In total, 16 pancreas transplants have been performed, of which 12 were simultaneous pancreas-kidney transplants, 1 was pancreas after kidney, and 3 were pancreas alone transplants. One pancreatic islet transplant was also performed in a patient who had already undergone kidney transplantation. Patient and pancreas graft survivals at 1 year were 86.7% and 73.3%, respectively, and 80% and 73.3% at five years (pancreas survival is defined as normoglycemia and insulin-independence). Lung transplant has been performed in 133 patients (116 double and 17 single lung). Eleven were pediatric (8% of all transplants). The 1-month, 1-year, and 5-year overall graft survivals were, 93.8%, 81.4%, and 75.6%, respectively. Heart transplantation has been performed in 133 adults (85% were male). Coronary artery disease and cardiomyopathy were the leading underlying heart disease diagnoses leading to transplant. Mechanical support (ventricular assist device or extracorporeal membrane oxygenation) as a bridge to transplant was used in 18% of the heart transplant cases. One-year heart graft survival was 83% and 5-year heart graft survival was 81%.

Recipient-donor age matching in liver transplantation: a single-center experience

OBJECTIVE

The aim of this study was to investigate whether donor age was a predictor of outcomes in liver transplantation, representing an independent risk factor as well as its impact related to recipient age-matching.

METHODS

We analyzed prospectively collected data from 221 adult liver transplantations performed from January 2006 to September 2009.

RESULTS

Compared with recipients who received grafts from donors <60 years old, transplantation from older donors was associated with significantly higher rates of graft rejection (9.5% vs 3.5%; P = .05) and worse graft survival (P = .021). When comparing recipient and graft survivals according to age matching, we observed significantly worse values for age-mismatched (P values .029 and .037, respectively) versus age-matched patients. After adjusting for covariates in a multivariate model, age mismatch was an independent risk factor for patient death (hazard ratio [HR] 2.13, 95% confidence interval [CI] 1.1-4.17; P = .027) and graft loss (HR 3.86, 95% CI 1.02-15.47; P = .046).

CONCLUSIONS

The results of this study suggest to that optimized donor allocation takes into account both donor and recipient ages maximize survival of liver-transplanted patients.

Liver regeneration after liver resection: Clinical aspects and correlation with infective complications

AIM: To investigate whether early liver regeneration after resection in patients with hepatic tumors might be influenced by post-operative infective complications.

METHODS: A retrospective analysis of 27 liver resections for tumors performed in a single referral center from November 2004 to January 2010. Regeneration was evaluated by multidetector computed tomography at a mean follow-up of 43.85 d. The Clavien-Dindo classification was used to evaluate postoperative events in the first 6 mo after transplantation, and Centers for Disease Control and Prevention definitions were used for healthcare associated infections data. Generalized linear regression models with Gaussian family distribution and log link function were used to reveal the principal promoters of early liver regeneration.

RESULTS: Ten of the 27 patients (37%) underwent chemotherapy prior to surgery, with a statistically significant prevalence of patients with metastasis (P = 0.007). Eight patients (30%) underwent embolization, 3 with primary tumors, and 5 with secondary tumors. Twenty patients (74%) experienced complications, with 12 (60%) experiencing Clavien-Dindo Grade 3a to 5 complications. Regeneration ≥ 100% occurred in 10 (37%) patients. The predictors were smaller future remnant liver volume (-0.002; P < 0.001), and a greater spleen volume/future remnant liver volume ratio (0.499; P = 0.01). Patients with a resection of ≥ 5 Couinaud segments experienced greater early regeneration (P = 0.04). Nine patients experienced surgical site infections, and in 7 cases Clavien-Dindo Grade 3a to 4 complications were detected (P = 0.016). There were no significant differences between patients with primary or secondary tumors, and either onset or infections or severity of surgical complications.

CONCLUSION: Regardless of the onset of infective complications, future remnant liver and spleen volumes may be reliable predictors of early liver regeneration after hepatic resection on an otherwise healthy liver.

A Bayesian methodology to improve prediction of early graft loss after liver transplantation derived from the liver match study

BACKGROUND

To generate a robust predictive model of Early (3 months) Graft Loss after liver transplantation, we used a Bayesian approach to combine evidence from a prospective European cohort (Liver-Match) and the United Network for Organ Sharing registry.

METHODS

Liver-Match included 1480 consecutive primary liver transplants performed from 2007 to 2009 and the United Network for Organ Sharing a time-matched series of 9740 transplants. There were 173 and 706 Early Graft Loss, respectively. Multivariate analysis identified as significant predictors of Early Graft Loss: donor age, donation after cardiac death, cold ischaemia time, donor body mass index and height, recipient creatinine, bilirubin, disease aetiology, prior upper abdominal surgery and portal thrombosis.

RESULTS

A Bayesian Cox model was fitted to Liver-Match data using the United Network for Organ Sharing findings as prior information, allowing to generate an Early Graft Loss-Donor Risk Index and an Early Graft Loss-Recipient Risk Index. A Donor-Recipient Allocation Model, obtained by adding Early Graft Loss-Donor Risk Index to Early Graft Loss-Recipient Risk Index, was then validated in a distinct United Network for Organ Sharing (year 2010) cohort including 2964 transplants. Donor-Recipient Allocation Model updating using the independent Turin Transplant Centre dataset, allowed to predict Early Graft Loss with good accuracy (c-statistic: 0.76).

CONCLUSION

Donor-Recipient Allocation Model allows a reliable donor and recipient-based Early Graft Loss prediction. The Bayesian approach permits to adapt the original Donor-Recipient Allocation Model by incorporating evidence from other cohorts, resulting in significantly improved predictive capability.

In vivo multiclonal transfer of bla(KPC-3) from Klebsiella pneumoniae to Escherichia coli in surgery patients

During active surveillance at the Mediterranean Institute for Transplantation and Advanced Specialized Therapies (ISMETT, Palermo, Italy) with the CARBA screening medium, five pairs of Klebsiella pneumoniae carbapenemase (KPC)-producing K. pneumoniae and Escherichia coli strains were isolated in each of five colonized patients. In each patient, lateral gene transfer was demonstrated by comparing K. pneumoniae and E. coli strains, both possessing KPC-3, Tn4401a and pKpQIL-IT elements. The isolates were found to be multiclonal by multilocus sequence typing (sequence type (ST) 512 related to ST258, and ST307 belonging to a clonal complex different from the habitual sequence clone ST258 isolated in Italy) and pulsed-field gel electrophoresis. The results of our study highlight the easy transfer of KPC among Enterobacteriaceae colonizing the human intestine, and the active and careful surveillance required to identify and prevent the spread of these multidrug-resistant microorganisms.

Right hepatic lobe living donation: a 12 years single Italian center experience

Mini invasive techniques are taking over conventional open liver resections in the setting of left lateral segmentectomy for living liver donation, and hydride procedure are being implemented for the living related right hepatectomy. Our center routinely performs laparoscopic left lateral segmentectomy for pediatric recipient and has been the first in the Europe performing an entirely robotic right hepatectomy. Great emphasis is posed on living donor safety which is the first priority during the entire operation, then the most majority of our procedures are still conventional open right hepatectomy (RHLD), defined as removal of a portion of liver corresponding to Couinaud segments 5-8, in order to obtain a graft for adult to adult living related liver transplant. During this 10 years period some changes, herein highlighted, have occurred to our surgical techniques. This study reports the largest Italian experience with RHLD, focused on surgical technique evolution over a 10 years period. Donor safety must be the first priority in right-lobe living-related donation: the categorization of complications of living donors, specially, after this "highly sensitive" procedure, reflects the need for prompt and detailed reports.

Isolation and characterization of multipotent cells from human fetal dermis

We report that cells from human fetal dermis, termed here multipotent fetal dermal cells, can be isolated with high efficiency by using a nonenzymatic, cell outgrowth method. The resulting cell population was consistent with the definition of mesenchymal stromal cells by the International Society for Cellular Therapy. As multipotent fetal dermal cells proliferate extensively, with no loss of multilineage differentiation potential up to passage 25, they may be an ideal source for cell therapy to repair damaged tissues and organs. Multipotent fetal dermal cells were not recognized as targets by T lymphocytes in vitro, thus supporting their feasibility for allogenic transplantation. Moreover, the expansion protocol did not affect the normal phenotype and karyotype of cells. When compared with adult dermal cells, fetal cells displayed several advantages, including a greater cellular yield after isolation, the ability to proliferate longer, and the retention of differentiation potential. Interestingly, multipotent fetal dermal cells expressed the pluripotency marker SSEA4 (90.56 ± 3.15% fetal vs. 10.5 ± 8.5% adult) and coexpressed mesenchymal and epithelial markers (>80% CD90(+)/CK18(+) cells), coexpression lacking in the adult counterparts isolated under the same conditions. Multipotent fetal dermal cells were able to form capillary structures, as well as differentiate into a simple epithelium in vitro, indicating skin regeneration capabilities.

Comparison of hematologic, biochemical, and coagulation parameters in α1,3-galactosyltransferase gene-knockout pigs, wild-type pigs, and four primate species

BACKGROUND

The increasing availability of genetically engineered pigs is steadily improving the results of pig organ and cell transplantation in non-human primates (NHPs). Current techniques offer knockout of pig genes and/or knockin of human genes. Knowledge of normal values of hematologic, biochemical, coagulation, and other parameters in healthy genetically engineered pigs and NHPs is important, particularly following pig organ transplantation in NHPs. Furthermore, information on parameters in various NHP species may prove important in selecting the optimal NHP model for specific studies.

METHODS

We have collected hematologic, biochemical, and coagulation data on 71 α1,3-galactosyltransferase gene-knockout (GTKO) pigs, 18 GTKO pigs additionally transgenic for human CD46 (GTKO.hCD46), four GTKO.hCD46 pigs additionally transgenic for human CD55 (GTKO.hCD46.hCD55), and two GTKO.hCD46 pigs additionally transgenic for human thrombomodulin (GTKO.hCD46.hTBM).

RESULTS

We report these data and compare them with similar data from wild-type pigs and the three major NHP species commonly used in biomedical research (baboons, cynomolgus, and rhesus monkeys) and humans, largely from previously published reports.

CONCLUSIONS

Genetic modification of the pig (e.g., deletion of the Gal antigen and/or the addition of a human transgene) (i) does not result in abnormalities in hematologic, biochemical, or coagulation parameters that might impact animal welfare, (ii) seems not to alter metabolic function of vital organs, although this needs to be confirmed after their xenotransplantation, and (iii) possibly (though, by no means certainly) modifies the hematologic, biochemical, and coagulation parameters closer to human values. This study may provide a good reference for those working with genetically engineered pigs in xenotransplantation research and eventually in clinical xenotransplantation.

Perivascular mesenchymal progenitors in human fetal and adult liver

The presence of mesenchymal stem cells (MSCs) has been described in various organs. Pericytes possess a multilineage differentiation potential and have been suggested to be one of the developmental sources for MSCs. In human liver, pericytes have not been defined. Here, we describe the identification, purification, and characterization of pericytes in human adult and fetal liver. Flow cytometry sorting revealed that human adult and fetal liver contains 0.56%±0.81% and 0.45%±0.39% of CD146(+)CD45(-)CD56(-)CD34(-) pericytes, respectively. Of these, 41% (adult) and 30% (fetal) were alkaline phosphatase-positive (ALP(+)). In situ, pericytes were localized around periportal blood vessels and were positive for NG2 and vimentin. Purified pericytes could be cultured extensively and had low population doubling times. Immunofluorescence of cultures demonstrated that cells were positive for pericyte and mesenchymal cell markers CD146, NG2, CD90, CD140b, and vimentin, and negative for endothelial, hematopoietic, stellate, muscle, or liver epithelial cell markers von Willebrand factor, CD31, CD34, CD45, CD144, CD326, CK19, albumin, α-fetoprotein, CYP3A7, glial fibrillary acid protein, MYF5, and Pax7 by gene expression; myogenin and alpha-smooth muscle actin expression were variable. Fluorescence-activated cell sorting analysis of cultures confirmed surface expression of CD146, CD73, CD90, CD10, CD13, CD44, CD105, and ALP and absence of human leukocyte antigen-DR. In vitro differentiation assays demonstrated that cells possessed robust osteogenic and myogenic, but low adipogenic and low chondrogenic differentiation potentials. In functional in vitro assays, cells had typical mesenchymal strong migratory and invasive activity. In conclusion, human adult and fetal livers harbor pericytes that are similar to those found in other organs and are distinct from hepatic stellate cells.

The Charlson comorbidity index as a predictor of outcomes in liver transplantation: single-center experience

Several comorbidity indices, such as the Child-Turcotte-Pugh (CTP) score and the Model for End-Stage Liver Disease (MELD) score, have been used to optimize available organ resources and adjust priorities in diagnosis and allocation of grafts for patients who are candidates for liver transplantation. There have also been various attempts to create instruments to accurately predict outcomes after liver transplantation, but none has proved to be truly applicable, with the exception of the Charlson comorbidity index (CCI). We retrospectively reviewed data of 221 liver recipients, including living-related liver transplantation and multiple organ transplantation performed between January 2006 and September 2009. Survival analysis revealed a significant association of the CCI with decreased posttransplantation patient survival (P = .003). Furthermore, Kaplan-Meier plots and log-rank test showed a significant association between graft survival and the score (P = .039). Our data suggest that the CCI is a simple tool for the evaluation of comorbidity and that increased preoperative patient comorbidity increases the risk of graft loss and patient death after liver transplantation. The CCI should be considered an important tool for improving patient care because of its potential applications for patient management.

Immunobiology of liver xenotransplantation

Pigs are currently the preferred species for future organ xenotransplantation. With advances in the development of genetically modified pigs, clinical xenotransplantation is becoming closer to reality. In preclinical studies (pig-to-nonhuman primate), the xenotransplantation of livers from pigs transgenic for human CD55 or from α1,3-galactosyltransferase gene-knockout pigs+/- transgenic for human CD46, is associated with survival of approximately 7-9 days. Although hepatic function, including coagulation, has proved to be satisfactory, the immediate development of thrombocytopenia is very limiting for pig liver xenotransplantation even as a 'bridge' to allotransplantation. Current studies are directed to understand the immunobiology of platelet activation, aggregation and phagocytosis, in particular the interaction between platelets and liver sinusoidal endothelial cells, hepatocytes and Kupffer cells, toward identifying interventions that may enable clinical application.

Early regeneration of the remnant liver volume after right hepatectomy for living donation: a multiple regression analysis

Early liver regeneration was studied in a series of 70 patients who underwent right hepatectomy for living donation between November 2004 and January 2010. Liver regeneration was evaluated with multidetector computed tomography (MDCT) at a mean of 61.07 days after surgery. Presurgical variables [eg, age, weight, height, body mass index (BMI), liver function tests, creatinine levels, platelet counts, international normalized ratio, and glucose levels] and variables detected with preoperative MDCT imaging [eg, main portal vein diameter, steatosis, original liver volume, and spleen volume (SV)] were investigated as potential predictors of liver regeneration. The future remnant liver volume (FRLV) was preoperatively calculated with a virtual surgical cut. Liver function tests and creatinine levels were recorded on the 30th postoperative day. In addition, the onset of postoperative complications occurring within 90 days of surgery was analyzed, and the complications were codified according to the 5 tiers of the Clavien-Dindo classification. In 26 of the 70 patients (37.14%), 100% or greater hepatic regeneration had occurred at 2 months. There was no association between the clinical outcome and the liver regeneration rate. A stepwise multiple regression analysis showed that a higher BMI (coefficient = 0.035, P < 0.0001) and preoperative parameters such as a smaller FRLV (coefficient = -0.002, P < 0.0001) and a greater SV/FRLV ratio (coefficient = 1.196, P < 0.0001) were predictors of greater liver regeneration.

Endoscopy after radiology: two-step combined therapy for biliary stricture after Roux-en-Y hepaticojejunostomy

Benign postoperative anastomotic strictures after hepaticojejunostomy are difficult to manage. Before interventional techniques were developed, surgical intervention was the only option for treatment. A 28-year-old man underwent Whipple procedure with Roux-en-Y hepaticojejunostomy for abdominal trauma. Two years later, a late anastomotic biliary stricture was diagnosed. A percutaneous cholangiography showed a severe stricture in the hepaticojejunostomy. Because of the severity and length of the stricture, and the failure of repeated percutaneous balloon-dilations, we percutaneously placed a self-expandable metal stent, a nitinol polytetrafluoroethylene fully covered flared-type stent, 3 cm in length, with 10 mm of diameter. The patient was soon discharged home in good general condition that remained stable in the 6 months of follow up. To remove the biliary stent, we carried out single-balloon enteroscopy. The stent was captured with a standard polypectomy snare. To avoid injury to the mucosa, the stent was removed through the overtube, which remained in situ. Cholangiogram showed a normal biliary tree, with resolution of the anastomotic stenosis. The patient remained stable throughout the 8 months of follow up, and required no further biliary procedures. In cases of failure of standard procedures, this new two-step, combined percutaneous and endoscopic approach can be useful and feasible, avoiding surgery-related morbidity and mortality. However, the fact that these procedures should be carried out only by highly experienced endoscopists and interventional radiologists familiar with these specialized procedures cannot be overstressed.

Antiviral therapy and fibrosis progression in patients with mild-moderate hepatitis C recurrence after liver transplantation. A randomized controlled study

BACKGROUNDS/AIMS

We evaluated the effect of antiviral therapy on fibrosis progression in patients with histological features of mild/moderate HCV disease recurrence defined by a Grading score≥4 and Staging score up to 3 (Ishak) at 1 year after liver transplantation.

METHODS

Seventy-three consecutive patients with mild/moderate recurrence were randomized either to no treatment or to receive Pegilated-Interferon-alfa-2b and ribavirin for 52 weeks. Liver biopsies obtained at baseline (1 year after transplantation) and 2 years afterwards were evaluated for assessment of disease progression, defined as worsening of at least 2 staging points or progression to stage 4 or higher.

RESULTS

As for these two major histological end points there were no statistically significant differences between the 2 groups (36.1% vs. 50%, p=0.34 and 36.1% vs. 38.9%, p=1). Fifteen treated patients (41%) achieved a sustained virological response which was associated with a reduced risk of fibrosis worsening for both endpoints when compared to viremic patients (p=0.04).

CONCLUSIONS

Although antiviral-therapy was beneficial in preventing fibrosis progression in patients achieving a sustained virological response, the majority of the overall population of our patients with mild-moderate disease recurrence could not benefit from antiviral therapy either because they either could not be treated or did not respond to treatment (EudraCT number: 2005-005760).

Porcine alanine transaminase after liver allo-and xenotransplantation

Aspartate transaminase (AST) and alanine transaminase (ALT) are measured following liver transplantation as indicators of hepatocellular injury. During a series of orthotopic liver allo-and xenotransplants, we observed that there was an increase in AST in all cases. The anticipated concomitant rise in ALT did not occur when a wild-type (WT) pig was the source of the liver graft, but did occur when a baboon or a genetically engineered (α1,3-galactosyltransferase gene-knockout [GTKO]) pig was the source of the graft. We hypothesized that the cience of Galα1,3Gal in GTKO pig livers may render pig hepatocytes similar to human and baboon hepatocytes in their response to hepatocellular injury. Reviewing the literature, after WT pig liver allotransplantation or xenotransplantation, in the majority of reports, although changes in AST were reported, no mention was made of changes in ALT, suggesting that there was no change in ALT. However, Ramirez et al. reported two cases of liver xenotransplants from hCD55 pigs, following which there were increases in both AST and ALT, suggesting that it is not simply the cience of expression of Galα1,3Gal that is the cause. We acknowledge that our observation is based on a small number of experiments, but we believe it is worth recording.

The first report of orthotopic liver transplantation in the Western world

Until the present time, the first experimental liver transplant which led to the development of human liver transplantation is attributed to C. Stuart Welch who performed a heterotopic transplant in the canine species in 1955. In 1956, Jack Cannon is credited with the first animal orthotopic liver transplant although the species was not disclosed. This report is intended to set the historical record straight by acknowledging that Vittorio Staudacher in 1952 was the first to perform a liver transplant in a large animal model.

Potential factors influencing the development of thrombocytopenia and consumptive coagulopathy after genetically modified pig liver xenotransplantation

Upregulation of tissue factor (TF) expression on activated donor endothelial cells (ECs) triggered by the immune response (IR) has been considered the main initiator of consumptive coagulopathy (CC). In this study, we aimed to identify potential factors in the development of thrombocytopenia and CC after genetically engineered pig liver transplantation in baboons. Baboons received a liver from either an α1,3-galactosyltransferase gene-knockout (GTKO) pig (n = 1) or a GTKO pig transgenic for CD46 (n = 5) with immunosuppressive therapy. TF exposure on recipient platelets and peripheral blood mononuclear cell (PBMCs), activation of donor ECs, platelet and EC microparticles, and the IR were monitored. Profound thrombocytopenia and thrombin formation occurred within minutes of liver reperfusion. Within 2 h, circulating platelets and PBMCs expressed functional TF, with evidence of aggregation in the graft. Porcine ECs were negative for expression of P- and E-selectin, CD106, and TF. The measurable IR was minimal, and the severity and rapidity of thrombocytopenia were not alleviated by prior manipulation of the IR. We suggest that the development of thrombocytopenia/CC may be associated with TF exposure on recipient platelets and PBMCs (but possibly not with activation of donor ECs). Recipient TF appears to initiate thrombocytopenia/CC by a mechanism that may be independent of the IR.

Thrombocytopenia after pig-to-baboon liver xenotransplantation: where do platelets go?

BACKGROUND

In baboons with orthotopic pig liver xenografts, profound thrombocytopenia was observed within 1 h after reperfusion. Assessment of the fate of platelets may shed light on the underlying mechanisms leading to thrombocytopenia and may allow preventive therapies to be introduced.

METHODS

Platelet-white blood cell (WBC) aggregation was studied in two baboons that received orthotopic liver xenografts from α1,3-galactosyltransferase gene-knockout pigs transgenic for human CD46 (GTKO/CD46). Percentages of CD42a-positive platelet aggregates with WBC-subtypes were determined by flow cytometry, and absolute numbers (per mm(3) ) were calculated. Platelet aggregates in the liver xenografts were identified by immunofluorescence and electron microscopy. Mean platelet volume (MPV) was determined before and after transplantation.

RESULTS

After pig liver reperfusion, profound thrombocytopenia was associated with aggregation of platelets with WBC-subtypes. Increasing aggregation of platelets with WBC-subtypes was detected throughout the post-transplant period until the recipient was euthanized. Significant negative correlation was found between platelet counts in the blood and aggregation of platelets with monocytes (P < 0.01) and neutrophils (P < 0.01), but not with lymphocytes. MPV remained within the normal range. Two hours after reperfusion, platelet and fibrin deposition were already detected in the liver xenografts by immunofluorescence and by electron microscopy.

CONCLUSIONS

Following liver xenotransplantation, the early disappearance of platelets from the circulation was at least in part due to their aggregation with circulating WBC, which may augment their deposition in the liver xenograft and native lungs. Prevention of platelet aggregation with monocytes and neutrophils is likely beneficial in reducing their subsequent sequestration in the liver xenograft and native organs.

Multidisciplinary imaging of liver hydatidosis

Liver hydatidosis is a parasitic endemic disease affecting extensive areas in our planet, a significant stigma within medicine to manage because of its incidence, possible complications, and diagnostic involvements. The diagnosis of liver hydatidosis should be as fast as possible because of the relevant complications that may arise with disease progression, involving multiple organs and neighboring structures causing disruption, migration, contamination. The aim of this essay is to illustrate the role of imaging as ultrasonography (US), multi detector row computed tomography, and magnetic resonance imaging (MRI) in the evaluation of liver hydatidosis: the diagnosis, the assessment of extension, the identification of possible complications and the monitoring the response to therapy. US is the screening method of choice. Computed tomography (CT) is indicated in cases in which US is inadequate and has high sensitivity and specificity for calcified hydatid cysts. Magnetic resonance is the best imaging procedure to demonstrate a cystic component and to show a biliary tree involvement. Diagnostic tests such as CT and MRI are mandatory in liver hydatidosis because they allow thorough knowledge regarding lesion size, location, and relations to intrahepatic vascular and biliary structures, providing useful information for effective treatment and decrease in post-operative morbidity. Hydatid disease is classified into four types on the basis of their radiologic appearance.

Intraductal aspiration: a promising new tissue-sampling technique for the diagnosis of suspected malignant biliary strictures

BACKGROUND

Brushing is the most commonly used technique for biliary sampling at ERCP, despite its limited sensitivity.

OBJECTIVE

To evaluate intraductal aspiration (IDA) as a new combined endoscopic technique for cytodiagnosis, its cellular adequacy, diagnostic accuracy for cancer detection, feasibility, and safety.

DESIGN

Prospective, observational study.

SETTING

Single tertiary referral center.

MAIN OUTCOME MEASUREMENTS

IDA cellular adequacy, diagnostic accuracy for cancer detection, feasibility, and safety.

PATIENTS AND METHODS

From April 2009 to September 2010, 42 consecutive patients with suspected malignant biliary stricture underwent ERCP, with tissue sampling obtained with IDA. IDA included performance of standard brushing in all patients. After standard brushing, to perform IDA, we removed the brush from its catheter and used the tip of the catheter as a scraping device. The tip was scraped back and forth across the stricture at least 10 times. The catheter and a suction line were connected to a specimen trap to obtain intraductal aspiration of fluids and samplings.

RESULTS

Our cytopathologists found adequate cellular yield in 39 of the 42 IDA samples (92.8%) versus 15 of the 42 brushing samples (35.7%) (P < .001). IDA showed a significantly higher sensitivity than brushing (89% vs 78% for adequate samples and 89% vs 37% for all samples) and provided significantly superior cellular adequacy (92.8% vs 35.7%).

LIMITATIONS

Observational study, small number of patients.

CONCLUSIONS

IDA significantly improves brushing cellular adequacy and has high sensitivity for cancer detection. It was also safe, simple, rapid, and applicable during routine diagnostic ERCP, with no additional costs.

Single-session percutaneous alcohol sclerotherapy for the treatment of isolated draining intrahepatic biliary duct in a five-month-old liver transplant recipient

The present paper describes the first reported successful use of a single session of percutaneous alcohol sclerotherapy for the treatment of an excluded segmental biliary duct in a five-month-old left lateral liver recipient. A concomitant stricture of the hepaticojejunostomy was also successfully treated using standard percutaneous balloon dilatation. The patient has remained in good general condition for the next 26 months.

Fully covered metallic stents in biliary stenosis after orthotopic liver transplantation

BACKGROUND AND STUDY AIMS

Data from a preliminary study suggested that the placement of a fully covered metal stent may be a valid alternative to surgery in patients who do not respond to standard endoscopic treatment. The aims of the current study were to evaluate the clinical success of self-expandable metallic stents (SEMS) in a large cohort of patients and with a long followup,and the effectiveness of SEMS placement as a first-line procedure.

MATERIALS AND METHODS

Between January 2008 and August 2010, 54 consecutive patients with biliary complications following orthotopic liver transplantation were treated with SEMS placement:39 after failure of conventional endoscopic therapy (Group I), and 15 with no previous endoscopic treatment who were undergoing SEMS placement as first-line treatment for complications(Group II).

RESULTS

In Group I, resolution after SEMS removal was observed in 71.8% of patients. Mean followup after resolution was 22.1 ±10 months. Recurrence of the complication was observed in 14.3%of patients after a mean of 8.5 months and SEMS migration was observed in 33.3% of patients. In Group II, resolution was observed in 53.3% of patients.Mean follow-up after resolution was 14.4±2.2 months. Recurrence was observed in 25% of patients and SEMS migration was observed in 46.7 %.

CONCLUSIONS

For endotherapy of biliary complications after orthotopic liver transplantation, metallic stents should not be used as the primary modality. In patients in whom the standard approach fails, treatment with temporary SEMS placement can solve biliary complications in almost three-quarters of cases; however stent migration(33 %) remains a problem.

Transjugular liver biopsy in pediatric patients with left split liver transplantation and severe coagulation impairment

The aim of this study is to report our experience in TJLB performed in pediatric patients who underwent partial LT using a left lateral segments graft. Eight consecutive TJLBs were performed in six patients with contraindication to percutaneous biopsy owing to severe coagulation impairment and ascites. All procedures were performed using an 18-gauge automated core needle biopsy. Median age of the patients was 44 months (range, 11-198). Median patients' weight was 13 kg (range, 8-45). Technical success was achieved in all cases without complications. The specimens were adequate for the diagnosis in all cases.